WO2010078392A2 - Processes of producing fermentation products - Google Patents

Processes of producing fermentation products Download PDF

Info

Publication number
WO2010078392A2
WO2010078392A2 PCT/US2009/069773 US2009069773W WO2010078392A2 WO 2010078392 A2 WO2010078392 A2 WO 2010078392A2 US 2009069773 W US2009069773 W US 2009069773W WO 2010078392 A2 WO2010078392 A2 WO 2010078392A2
Authority
WO
WIPO (PCT)
Prior art keywords
fermentation
starch
alpha
fermenting
amylase
Prior art date
Application number
PCT/US2009/069773
Other languages
French (fr)
Other versions
WO2010078392A3 (en
Inventor
Jason Holmes
Original Assignee
Novozymes North America, Inc.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Novozymes North America, Inc. filed Critical Novozymes North America, Inc.
Publication of WO2010078392A2 publication Critical patent/WO2010078392A2/en
Publication of WO2010078392A3 publication Critical patent/WO2010078392A3/en

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12PFERMENTATION OR ENZYME-USING PROCESSES TO SYNTHESISE A DESIRED CHEMICAL COMPOUND OR COMPOSITION OR TO SEPARATE OPTICAL ISOMERS FROM A RACEMIC MIXTURE
    • C12P7/00Preparation of oxygen-containing organic compounds
    • C12P7/02Preparation of oxygen-containing organic compounds containing a hydroxy group
    • C12P7/04Preparation of oxygen-containing organic compounds containing a hydroxy group acyclic
    • C12P7/06Ethanol, i.e. non-beverage
    • C12P7/08Ethanol, i.e. non-beverage produced as by-product or from waste or cellulosic material substrate
    • C12P7/10Ethanol, i.e. non-beverage produced as by-product or from waste or cellulosic material substrate substrate containing cellulosic material
    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12PFERMENTATION OR ENZYME-USING PROCESSES TO SYNTHESISE A DESIRED CHEMICAL COMPOUND OR COMPOSITION OR TO SEPARATE OPTICAL ISOMERS FROM A RACEMIC MIXTURE
    • C12P19/00Preparation of compounds containing saccharide radicals
    • C12P19/02Monosaccharides
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E50/00Technologies for the production of fuel of non-fossil origin
    • Y02E50/10Biofuels, e.g. bio-diesel

Definitions

  • the present invention relates to processes of fermenting plant derived materials into desired fermentation products.
  • the invention also relates to processes of producing desired fermentation products from plant materials using a fermenting organism and compositions that can be used in such processes.
  • alcohols e.g., ethanol, methanol, butanol, 1 ,3-propanediol
  • organic acids e.g., citric acid, acetic acid, itaconic acid, lactic acid, gluconic acid, gluconate, lactic acid, succinic acid, 2,5-diketo-D-gluconic acid.
  • Figure 1 Effect of capsaicin on ethanol yield from combination of alpha-amylase and glucoamylase in one-step simultaneous saccharification and fermentation (SSF) process.
  • Figure 2 Effect of capsaicin and icilin on ethanol yield from hydrolyzed PCS fermented with RED STARTM yeast.
  • Figure 3 Effect of capsaicin and icilin on ethanol yield from hydrolyzed PCS fermented with RWB218 yeast.
  • the invention relates to processes of fermenting sugars derived from plant material into a fermentation product using a fermenting organism, wherein one or more TRP channel agonists is present during fermentation.
  • the invention in another aspect relates to processes of producing a fermentation product from starch-containing material comprising the steps of: i) liquefying starch-containing material; ii) saccharifying the liquefied material; iii) fermenting with a fermenting organism; wherein fermentation is carried out in accordance with a fermentation process of the invention.
  • the invention in another aspect relates to processes of producing a fermentation product from starch-containing material, comprising the steps of: (a) saccharifying starch-containing material at a temperature below the initial gelatinization temperature of said starch-containing material;
  • the invention relates to processes of producing a fermentation product from sugars derived from lignocellulose-containing material, comprising the steps of:
  • step (b) hydrolysing the material obtained in step (a); (c) fermenting using a fermenting organism; wherein fermentation is carried out in accordance with a fermentation process of the invention.
  • the invention relates to composition suitable for use in a process of the invention comprising one or more TRP channel agonist compounds and an enzyme and/or a fermenting organism.
  • the invention relates to the use of one or more TRP channel agonist compounds for propagating fermenting organisms and/or in fermentation processes.
  • the present invention relates to processes of fermenting plant derived material into a desired fermentation product.
  • the invention also provides processes for producing desired fermentation products from plant material using a fermenting organism.
  • the invention relates to compositions that can be used in such processes and to the use of TRP channel agonist compounds for propagation of fermenting organisms and/or fermentations.
  • the yeast viability may also be improved.
  • TRP channel agonist compounds only need to be present during fermentation in very low concentration in order to provide the advantageous effect.
  • the starting material i.e., substrate for the fermenting organism in question
  • the starting material may be sugars derived from the degradation of plant material or parts or constituents thereof.
  • the starting material i.e., substrate for the fermenting organism in question
  • the stating material is sugars derived from starch-containing material.
  • the starting material is sugars derived from lignocellulose- containing material.
  • the invention relates to processes of fermenting plant material into a fermentation product using a fermenting organism, wherein one or more TRP channel agonist compounds is present during fermentation.
  • the TRP channel agonist compounds may be added before and/or during fermentation. In an embodiment the compounds are added to the fermentation medium. In an embodiment the compounds are present in the fermentation medium.
  • TRP channel agonist compounds and "TRP superfamily” are art- recognized terms well understood by one skilled in the art.
  • An "agonist” is generally a term used to describe a type of compound that binds and alters the activity of a receptor, in this case a TRP channel.
  • Transient receptor potential channel proteins or TRP channel proteins include a family of related ion channel proteins that are non-selectively permeable to ions, especially cat-ions, such as calcium and magnesium.
  • TRP channel proteins A group of these TRP channel proteins a referred to as the "TRP superfamily" and is divided into seven subfamilies encoded by at least 33 channel subunit genes:
  • TRPC canonical - associated with Focal segmental glomerulosclerosis
  • TRPV vanilloid
  • TRPA ankyrin
  • TRPM (melastatin) - associated with Hypomagnesemia with secondary hypocalcemia
  • TRPP polycystin
  • TRPML molecular leukemia
  • TRPN no mechanoreceptor potential C - not found in mammals.
  • TRPC subfamily The first is composed of the "classical” TRPs" (TRPC subfamily). Some TRPCs may be store-operated channels, whereas others appear to be activated by production of diacylglycerol or regulated through an exocytotic mechanism. Many members of a second subfamily (TRPV) function in sensory physiology and respond to heat, changes in osmolarity, odorants, and mechanical stimuli. Two members of the TRPM family function in sensory perception and three TRPM proteins are chanzymes, which contain C-terminal enzyme domains. The fourth and fifth subfamilies, TRPN and TRPA, include proteins with many ankyrin repeats.
  • TRPN proteins function in mechanotransduction, whereas TRPA1 is activated by noxious cold and is also required for the auditory response.
  • members of the two Group 2 TRP subfamilies, TRPP and TRPML are distantly related to the group 1 TRPs. Mutations in the founding members of these latter subfamilies are responsible for human diseases.
  • Each of the TRP subfamilies are represented by members in worms and flies, providing the potential for using genetic approaches to characterize the normal functions and activation mechanisms of these channels.
  • TRP channel agonist compounds include compounds selected from the group consisting of resiniferatoxin, piperine, olvanil, anadamide, 2-APB, camphor, 4alpha- PDD, 5'6'-EET, menthol, eucalyptol, icilin, cinnamaldehyde, allylisothiocyanate, delta 9 tetra hydrocannabiol, and capsaicin, or analogues thereof.
  • the TRP agonist compound is an agonist of a channel protein from the TRP superfamily TRPV.
  • the TRP channel agonist compound is Capsaicin (8-methyl- ⁇ /-vanillyl-6-nonenamide). In another specific embodiment the TRP channel agonist compound is icilin.
  • the TRP channel agonist compound(s) may in an embodiment be of plant origin.
  • Capsaicin is the component of chili peppers that is responsible for the "heat” or burning sensation.
  • chili peppers are plants belonging to the genus Capsicum.
  • the TRP channel agonist compound(s) may in another embodiment be synthetic.
  • Icilin is a synthetic agonist compound of the transient receptor potential M8 (TRPM8) channel.
  • TRPM8 transient receptor potential M8
  • an effective amount includes concentrations in the range from 0.01 mM-100 mM as determined by HPLC.
  • the fermentation product yield may be boosted or increased.
  • the concentration of the TRP channel agonist compound needed to obtain a fermentation yield increase is low, as indicated above.
  • the viability of the yeast may also be increased by the presence of the TRP channel agonist compound. It is to be understood that according to the invention the concentration of the TRP channel agonist compounds are comparably higher than those concentrations when no such compounds are present or added.
  • fermenting organism refers to any organism, including bacterial and fungal organisms, including yeast and filamentous fungi, suitable for producing a desired fermentation product.
  • suitable fermenting organisms according to the invention are able to ferment, i.e., convert sugars, such as glucose, fructose maltose, xylose, mannose and/or arabinose, directly or indirectly into the desired fermentation product.
  • Examples of fermenting organisms include fungal organisms, such as yeast.
  • Preferred yeast includes strains of the genus Saccharomyces, in particular a strain of Saccharomyces cerevisiae or Saccharomyces uvarum; a strain of Pichia, in particular Pichia stipitis or Pichia pasto ⁇ s; a strain of the genus Candida, in particular a strain of Candida utilis, Candida arabinofermentans, Candida diddensii, Candida sonorensis, Candida shehatae, Candida tropicalis, or Candida boidinii.
  • yeast includes strains of Hansenula, in particular Hansenula polymorpha or Hansenula anomala; strains of Kluyveromyces, in particular Kluyveromyces marxianus or Kluyveromyces fagilis, and strains of Schizosaccharomyces, in particular Schizosaccharomyces pombe.
  • Preferred bacterial fermenting organisms include strains of Escherichia, in particular Escherichia coli, strains of Zymomonas, in particular Zymomonas mobilis, strains of Zymobacter, in particular Zymobactor palmae, strains of Klebsiella in particular Klebsiella oxytoca, strains of Leuconostoc, in particular Leuconostoc mesenteroides, strains of Clostridium, in particular Clostridium butyricum, strains of Enterobacter, in particular Enterobacter aerogenes and strains of Thermoanaerobacter, in particular Thermoanaerobacter BG1 L1 (Appl. Microbiol.
  • Lactobacillus are also envisioned as are strains of Corynebacterium glutamicum R, Bacillus thermoglucosidaisus, and Geobacillus thermoglucosidasius.
  • the fermenting organism is a C6 sugar fermenting organism, such as a strain of, e.g., Saccharomyces cerevisiae.
  • C5 sugar fermenting organisms are contemplated. Most C5 sugar fermenting organisms also ferment C6 sugars. Examples of C5 sugar fermenting organisms include strains of Pichia, such as of the species Pichia stipitis. C5 sugar fermenting bacteria are also known. Also some Saccharomyces cerevisae strains ferment C5 (and C6) sugars. Examples are genetically modified strains of Saccharomyces spp. that are capable of fermenting C5 sugars include the ones concerned in, e.g., Ho et al., 1998, Applied and Environmental Microbiology, p.
  • one or more fermenting organism(s) is(are) added to the fermentation medium so that the viable fermenting organism, such as yeast, count per ml_ of fermentation medium is in the range from 10 5 to 10 12 , preferably from 10 7 to 10 10 , especially about 5x10 7 .
  • yeast includes, e.g., RED STARTM and ETHANOL REDTM yeast (available from Fermentis/Lesaffre, USA), FALI (available from Fleischmann's Yeast, USA), SUPERSTART and THERMOSACCTM fresh yeast (available from Ethanol Technology, Wl, USA), BIOFERM AFT and XR (available from NABC - North American Bioproducts Corporation, GA, USA), GERT STRAND (available from Gert Strand AB, Sweden), and FERMIOL (available from DSM Specialties).
  • RED STARTM and ETHANOL REDTM yeast available from Fermentis/Lesaffre, USA
  • FALI available from Fleischmann's Yeast, USA
  • SUPERSTART and THERMOSACCTM fresh yeast available from Ethanol Technology, Wl, USA
  • BIOFERM AFT and XR available from NABC - North American Bioproducts Corporation, GA, USA
  • GERT STRAND available from Gert Strand AB, Sweden
  • FERMIOL available from DSM Specialties
  • the fermenting organism capable of producing a desired fermentation product from fermentable sugars including glucose, fructose maltose, xylose, mannose, and/or arabinose
  • the inoculated fermenting organism pass through a number of stages. Initially growth does not occur. This period is referred to as the "lag phase” and may be considered a period of adaptation.
  • the growth rate gradually increases. After a period of maximum growth the rate ceases and the fermenting organism enters "stationary phase”. After a further period of time the fermenting organism enters the "death phase" where the number of viable cells declines.
  • the TRP channel agonist compounds are added to the fermentation medium when the fermenting organism is in the lag phase.
  • the TRP channel agonist compounds are added to the fermentation medium when the fermenting organism is in exponential phase. In one embodiment the TRP channel agonist compounds are added to the fermentation medium when the fermenting organism is in stationary phase.
  • the TRP channel agonist compounds are added to the fermentation medium when the fermenting organism is in death phase.
  • Fermentation product means a product produced by a process including a fermentation step using one or more fermenting organisms.
  • Fermentation products contemplated according to the invention include alcohols (e.g., ethanol, methanol, butanol); organic acids (e.g., citric acid, acetic acid, itaconic acid, lactic acid, gluconic acid); ketones (e.g., acetone); amino acids (e.g., glutamic acid); gases (e.g., H 2 and CO 2 ); antibiotics (e.g., penicillin and tetracycline); enzymes; vitamins (e.g., riboflavin, B 12 , beta-carotene); and hormones.
  • alcohols e.g., ethanol, methanol, butanol
  • organic acids e.g., citric acid, acetic acid, itaconic acid, lactic acid, gluconic acid
  • ketones e.g., acetone
  • amino acids
  • the fermentation product is ethanol, e.g., fuel ethanol; drinking ethanol, i.e., potable neutral spirits; or industrial ethanol or products used in the consumable alcohol industry (e.g., beer and wine), dairy industry (e.g., fermented dairy products), leather industry and tobacco industry.
  • Preferred beer types comprise ales, stouts, porters, lagers, bitters, malt liquors, happoushu, high-alcohol beer, low-alcohol beer, low-calorie beer or light beer.
  • Preferred fermentation processes used include alcohol fermentation processes.
  • the fermentation product, such as ethanol, obtained according to the invention, may preferably be used as fuel. However, in the case of ethanol it may also be used as potable ethanol.
  • the plant material used in a process of the invention may be starch-containing material or lignocellulose-containing material, or a combination thereof.
  • the fermentation conditions are set based on, e.g., the kind of plant material, the fermentable sugars available, the fermenting organism(s) and/or the desired fermentation product.
  • One skilled in the art can easily determine suitable fermentation conditions.
  • the fermentation may according to one embodiment of the invention be carried out at conventionally used conditions. Preferred fermentation processes are according to the invention anaerobic.
  • fermenting organisms may be used for fermenting sugars derived from starch-containing material. Fermentations are conventionally carried out using yeast, such as Saccharomyces cerevisae, as the fermenting organism. However, bacteria and filamentous fungi may also be used as fermenting organisms. Some bacteria have higher fermentation temperature optimum than, e.g., Saccharomyces cerevisae. Therefore, fermentations may in such cases be carried out at temperatures as high as up to 75°C, e.g., at temperature between 40-70 0 C, such as 50- 60 0 C. The skilled person in the art can easily determine suitable fermentation conditions.
  • bacteria with a significantly lower temperature optimum down to around room temperature are also known.
  • suitable fermenting organisms can be found in the "Fermenting Organisms" section above.
  • the fermentation may in one embodiment go on for 24 to 96 hours, in particular for 35 to 60 hours.
  • the fermentation is carried out at a temperature between 20 to 40 0 C, preferably 26 to 34°C, in particular around 32°C.
  • the pH is from pH 3 to 6, preferably around pH 4 to 5.
  • SSF simultaneous hydrolysis/saccharification and fermentation
  • the hydrolysing enzyme(s), the fermenting organism(s) and agonist compound(s) may be added together.
  • the agonist compound(s) may also be added separately.
  • the temperature is preferably between 20 to 40 0 C, preferably 26 to 34°C, in particular around 32°C when the fermentation organism is a strain of Saccharomyces cerevisiae and the desired fermentation product is ethanol.
  • the process of the invention may be performed as a batch or as a continuous process.
  • the fermentation process of the invention may be conducted in an ultrafiltration system where the retentate is held under recirculation in the presence of solids, water, and the fermenting organism, and where the permeate is the desired fermentation product containing liquid. Equally contemplated if the process is conducted in a continuous membrane reactor with ultrafiltration membranes and where the retentate is held under recirculation in presence of solids, water, the fermenting organism and where the permeate is the fermentation product containing liquid.
  • the fermenting organism may be separated from the fermented slurry and recycled.
  • Fermentations are typically carried out at a pH in the range between 3 and 7, preferably from pH 3.5 to 6, such as around pH 5. Fermentations are typically ongoing for 24-96 hours.
  • fermenting organisms may be used for fermenting sugars derived from lignocellulose-containing material. Fermentations are typically carried out by yeast, bacteria or filamentous fungi, including the ones mentioned in the "Fermenting Organisms" section above. If the aim is C6 fermentable sugars the conditions are usually similar to starch fermentations as described above. However, if the aim is to ferment C5 sugars (e.g., xylose) or a combination of C6 and C5 fermentable sugars the fermenting organism(s) and/or fermentation conditions may differ.
  • C5 sugars e.g., xylose
  • Bacteria fermentations may be carried out at higher temperatures, such as up to 75°C, e.g., between 40-70 0 C, such as between 50-60 0 C, than conventional yeast fermentations, which are typically carried out at temperatures from 20-40 0 C.
  • bacteria fermentations at temperature as low as 20°C are also known.
  • Fermentations are typically carried out at a pH in the range between 3 and 7, preferably from pH 3.5 to 6, such as around pH 5. Fermentations are typically ongoing for 24-96 hours.
  • the present invention relates to a process for producing a fermentation product, especially ethanol, from starch-containing material, which process includes a liquefaction step and sequentially or simultaneously performed saccharification and fermentation steps.
  • the invention relates to a process for producing a fermentation product from starch- containing material comprising the steps of:
  • step (b) saccharifying the liquefied material obtained in step (a);
  • an alpha-amylase is used in the liquefying step (a).
  • a glucoamylase is used in the saccharifying step (b).
  • the agonist compounds are added before and/or during the fermentation step. In an embodiment the compounds are added to the fermentation medium.
  • the fermentation product such as ethanol
  • Suitable starch-containing starting materials are listed in the section “Starch-containing materials” section below.
  • Contemplated enzymes are listed in the “Enzymes” section below.
  • the liquefaction is preferably carried out in the presence of an alpha-amylase, preferably a bacterial alpha-amylase or acid fungal alpha-amylase.
  • the fermenting organism is preferably yeast, preferably a strain of Saccharomyces.
  • Suitable fermenting organisms are listed in the "Fermenting Organisms" section above.
  • step (b) and (c) are carried out sequentially or simultaneously (i.e., as SSF process).
  • the process of the invention further comprises, prior to the step (a), the steps of: x) reducing the particle size of the starch-containing material, preferably by milling; y) forming a slurry comprising the starch-containing material and water.
  • the aqueous slurry may contain from 10-55 wt. % dry solids, preferably 25-45 wt. % dry solids, more preferably 30-40 wt. % dry solids of starch-containing material.
  • the slurry is heated to above the gelatinization temperature and alpha-amylase, preferably bacterial and/or acid fungal alpha-amylase may be added to initiate liquefaction (thinning).
  • the slurry may in an embodiment be jet-cooked to further gelatinize the slurry before being subjected to an alpha-amylase in step (a) of the invention.
  • More specifically liquefaction may be carried out as a three-step hot slurry process.
  • the slurry is heated to between 60-95 0 C, preferably 80-85 0 C, and alpha-amylase is added to initiate liquefaction (thinning).
  • the slurry may be jet-cooked at a temperature between 95-140°C, preferably 105-125 0 C, for 1-15 minutes, preferably for 3-10 minutes, especially around 5 minutes.
  • the slurry is cooled to 60-95 0 C and more alpha-amylase is added to finalize hydrolysis (secondary liquefaction).
  • the liquefaction process is usually carried out at pH 4.5-6.5, in particular at a pH between 5 and 6.
  • the saccharification in step (b) may be carried out using conditions well known in the art. For instance, a full saccharification process may last up to from about 24 to about 72 hours, however, it is common only to do a pre-saccharification of typically 40-90 minutes at a temperature between 30-65°C, typically about 60°C, followed by complete saccharification during fermentation in a simultaneous saccharification and fermentation process (SSF process). Saccharification is typically carried out at temperatures from 30-65°C, typically around 60 0 C, and at a pH between 4 and 5, normally at about pH 4.5.
  • SSF process simultaneous saccharification and fermentation process
  • SSF simultaneous saccharification and fermentation
  • the invention relates to processes for producing a fermentation product from starch-containing material without gelatinization of the starch-containing material (i.e., uncooked starch-containing material).
  • the desired fermentation product such as ethanol
  • a process of the invention includes saccharifying (milled) starch-containing material, e.g., granular starch, below the gelatinization temperature, preferably in the presence of a carbohydrate-source generating enzyme to produce sugars that can be fermented into the desired fermentation product by a suitable fermenting organism.
  • the desired fermentation product preferably ethanol
  • un-gelatinized (i.e., uncooked) milled corn is produced from un-gelatinized (i.e., uncooked) milled corn.
  • the invention relates to processes of producing a fermentation product from starch-containing material, comprising the steps of:
  • steps (a) and (b) are carried out simultaneously (i.e., one step fermentation) or sequentially.
  • the fermentation step (b) may be carried in accordance with the fermentation process of the invention.
  • the fermentation product such as especially ethanol, may optionally be recovered after fermentation, e.g., by distillation.
  • Suitable starch-containing starting materials are listed in the section “Starch-containing Materials” section below.
  • Contemplated enzymes are listed in the “Enzymes” section below.
  • Alpha-amylases used are preferably acidic, preferably acid fungal alpha-amylases.
  • the fermenting organism is preferably yeast, preferably a strain of Saccharomyces. Suitable fermenting organisms are listed in the "Fermenting Organisms" section above.
  • the term "below the initial gelatinization temperature” means below the lowest temperature where gelatinization of the starch commences.
  • Starch heated in water typically begins to gelatinize between 50 0 C and 75°C; the exact temperature of gelatinization depends on the specific starch, and can readily be determined by the skilled artisan.
  • the initial gelatinization temperature may vary according to the plant species, to the particular variety of the plant species as well as with the growth conditions.
  • the initial gelatinization temperature of a given starch-containing material is the temperature at which birefringence is lost in 5% of the starch granules using the method described by Gorinstein and Lii, 1992, Starch/Starke 44 (12): 461-466.
  • a slurry of starch-containing material such as granular starch, having 10-55 wt. % dry solids, preferably 25-45 wt. % dry solids, more preferably 30-40 wt. % dry solids of starch-containing material may be prepared.
  • the slurry may include water and/or process waters, such as stillage (backset), scrubber water, evaporator condensate or distillate, side stripper water from distillation, or other fermentation product plant process water. Because the process of the invention is carried out below the gelatinization temperature and thus no significant viscosity increase takes place, high levels of stillage may be used if desired.
  • the aqueous slurry contains from about 1 to about 70 vol. % stillage, preferably 15-60% vol. % stillage, especially from about 30 to 50 vol. % stillage.
  • the starch-containing material may be prepared by reducing the particle size, preferably by dry or wet milling, to 0.05 to 3.0 mm, preferably 0.1-0.5 mm. After being subjected to a process of the invention at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91 %, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, or preferably at least 99% of the dry solids of the starch-containing material is converted into a soluble starch hydrolyzate. The process of this aspect of the invention is conducted at a temperature below the initial gelatinization temperature.
  • step (a) When step (a) is carried out separately from fermentation step (b) the temperature typically lies in the range between 30-75 0 C, preferably in the range from 45-60 0 C.
  • the following separate fermentation step (b) is then carried out at a temperature suitable for the fermenting organism, which typically is in the range between 25-4O 0 C when the fermenting organism is yeast.
  • step (a) and step (b) are carried out as a simultaneous saccharification and fermentation process.
  • the process is typically carried at a temperature between 25°C and 40 0 C, such as between 29°C and 35°C, such as between 30 0 C and 34°C, such as around 32°C, when the fermenting organism is yeast.
  • a temperature between 25°C and 40 0 C, such as between 29°C and 35°C, such as between 30 0 C and 34°C, such as around 32°C, when the fermenting organism is yeast.
  • process conditions are suitable.
  • simultaneous saccharification and fermentation is carried out so that the sugar level, such as glucose level, is kept at a low level such as below 6 wt. %, preferably below about 3 wt. %, preferably below about 2 wt. %, more preferred below about 1 wt. %., even more preferred below about 0.5 wt. %, or even more preferred 0.25% wt. %, such as below about 0.1 wt. %.
  • Such low levels of sugar can be accomplished by simply employing adjusted quantities of enzyme and fermenting organism. A skilled person in the art can easily determine which quantities of enzyme and fermenting organism to use.
  • the employed quantities of enzyme and fermenting organism may also be selected to maintain low concentrations of maltose in the fermentation broth. For instance, the maltose level may be kept below about 0.5 wt. % or below about 0.2 wt. %.
  • the process of the invention may be carried out at a pH in the range between 3 and
  • starch-containing starting material including granular starch
  • the starting material is generally selected based on the desired fermentation product.
  • starch-containing starting materials suitable for use in a process of present invention, include tubers, roots, stems, whole grains, corns, cobs, wheat, barley, rye, milo, sago, cassava, tapioca, sorghum, rice peas, beans, or sweet potatoes, or mixtures thereof, or cereals, sugar-containing raw materials, such as molasses, fruit materials, sugar cane or sugar beet, potatoes, and cellulose-containing materials, such as wood or plant residues, or mixtures thereof. Contemplated are both waxy and non-waxy types of corn and barley.
  • granular starch means raw uncooked starch, i.e., starch in its natural form found in cereal, tubers or grains. Starch is formed within plant cells as tiny granules insoluble in water. When put in cold water, the starch granules may absorb a small amount of the liquid and swell. At temperatures up to 50 0 C to 75°C the swelling may be reversible. However, with higher temperatures an irreversible swelling called “gelatinization" begins.
  • Granular starch to be processed may in an embodiment be a highly refined starch, preferably at least 90%, at least 95%, at least 97% or at least 99.5% pure, or it may be a more crude starch containing material comprising milled whole grain including non-starch fractions such as germ residues and fibers.
  • the raw material such as whole grain, is milled in order to open up the structure and allowing for further processing.
  • Two milling processes are preferred according to the invention: wet and dry milling. In dry milling whole kernels are milled and used. Wet milling gives a good separation of germ and meal (starch granules and protein) and is often applied at locations where the starch hydrolyzate is used in production of syrups. Both dry and wet milling is well known in the art of starch processing and is equally contemplated for the process of the invention.
  • the starch-containing material may be reduced in particle size, preferably by dry or wet milling, in order to expose more surface area.
  • the particle size is between 0.05 to 3.0 mm, preferably 0.1-0.5 mm, or so that at least 30%, preferably at least 50%, more preferably at least 70%, even more preferably at least 90% of the starch- containing material fit through a sieve with a 0.05 to 3.0 mm screen, preferably 0.1-0.5 mm screen.
  • the invention relates to processes of producing desired fermentation products from lignocellulose-containing material.
  • Conversion of lignocellulose-containing material into fermentation products, such as ethanol, has the advantages of the ready availability of large amounts of feedstock, including wood, agricultural residues, herbaceous crops, municipal solid wastes etc.
  • Lignocellulose-containing materials primarily consist of cellulose, hemicellulose, and lignin and are often referred to as "biomass”.
  • lignocellulose is not directly accessible to enzymatic hydrolysis. Therefore, the lignocellulose-containing material has to be pre-treated, e.g., by acid hydrolysis under adequate conditions of pressure and temperature, in order to break the lignin seal and disrupt the crystalline structure of cellulose. This causes solubilization of the hemicellulose and cellulose fractions.
  • the cellulose and hemicelluloses can then be hydrolyzed enzymatically, e.g., by cellulolytic enzymes, to convert the carbohydrate polymers into fermentable sugars which may be fermented into a desired fermentation product, such as ethanol.
  • the fermentation product may be recovered, e.g., by distillation.
  • the invention relates to a process of producing a fermentation product from lignocellulose-containing material, comprising the steps of:
  • the agonist compounds may be added before and/or during fermentation. In a preferred embodiment the agonist compounds are added to the fermentation medium.
  • the fermentation step (c) may be carried in accordance with the fermentation process of the invention. In preferred embodiments the steps are carried out as SSF, HHF or SHF process steps which will be described further below.
  • the lignocellulose-containing material may be pre-treated before being hydrolyzed and/or fermented.
  • the pre-treated material is hydrolyzed, preferably enzymatically, before and/or during fermentation.
  • the goal of pre-treatment is to separate and/or release cellulose, hemicellulose and/or lignin and this way improve the rate of enzymatic hydrolysis.
  • pre-treatment step (a) may be a conventional pre- treatment step known in the art. Pre-treatment may take place in aqueous slurry.
  • the lignocellulose-containing material may during pre-treatment be present in an amount between 10-80 wt. %, preferably between 20-50 wt.-%.
  • the lignocellulose-containing material may according to the invention be chemically, mechanically and/or biologically pre-treated before hydrolysis and/or fermentation.
  • Mechanical treatment (often referred to as physical treatment) may be used alone or in combination with subsequent or simultaneous hydrolysis, especially enzymatic hydrolysis, to promote the separation and/or release of cellulose, hemicellulose and/or lignin.
  • the chemical, mechanical and/or biological pre-treatment is carried out prior to the hydrolysis and/or fermentation.
  • the chemical, mechanical and/or biological pre-treatment is carried out simultaneously with hydrolysis, such as simultaneously with addition of one or more cellulolytic enzymes, or other enzyme activities mentioned below, to release fermentable sugars, such as glucose and/or maltose.
  • the pre-treated lignocellulose-containing material is washed and/or detoxified before hydrolysis step (b).
  • This may improve the fermentability of, e.g., dilute-acid hydrolyzed lignocellulose-containing material, such as corn stover and corn cobs.
  • Detoxification may be carried out in any suitable way, e.g., by steam stripping, evaporation, ion exchange, resin or charcoal treatment of the liquid fraction or by washing the pre-treated material.
  • gallic acid is added to either washed and/or unwashed lignocellulose-containing material before, during and/or after pre-treatment in step (a).
  • gallic acid may be used as a detoxification agent and may be added before, during and/or after pre-treatment in step (a).
  • chemical pre-treatment refers to any chemical treatment which promotes the separation and/or release of cellulose, hemicellulose and/or lignin.
  • suitable chemical pre-treatment steps include treatment with; for example, dilute acid, lime, alkaline, organic solvent, ammonia, sulfur dioxide, carbon dioxide.
  • wet oxidation and pH-controlled hydrothermolysis are also contemplated chemical pre-treatments.
  • the chemical pre-treatment is acid treatment, more preferably, a continuous dilute and/or mild acid treatment, such as, treatment with sulfuric acid, or another organic acid, such as acetic acid, citric acid, tartaric acid, succinic acid, or mixtures thereof. Other acids may also be used.
  • Mild acid treatment means in the context of the present invention that the treatment pH lies in the range from 1-5, preferably 1-3.
  • the acid concentration is in the range from 0.1 to 2.0 wt % acid, preferably sulphuric acid.
  • the acid may be mixed or contacted with the material to be fermented according to the invention and the mixture may be held at a temperature in the range of 160-220 0 C, such as 165-195°C, for periods ranging from minutes to seconds, e.g., 1-60 minutes, such as 2-30 minutes or 3-12 minutes. Addition of strong acids, such as sulphuric acid, may be applied to remove hemicellulose. This enhances the digestibility of cellulose.
  • Alkaline chemical pre-treatment with base e.g., NaOH and/or Na 2 CO 3 and/or the like
  • base e.g., NaOH and/or Na 2 CO 3 and/or the like
  • Pre-treatment methods using ammonia are described in, e.g., WO 2006/110891 , WO 2006/11899, WO 2006/11900, and WO 2006/110901 , which are hereby incorporated by reference.
  • Wet oxidation techniques involve use of oxidizing agents, such as: sulphite based oxidizing agents and the like.
  • solvent pre-treatments include treatment with DMSO (dimethyl sulfoxide) and the like.
  • Chemical pre-treatment is generally carried out for 1 to 60 minutes, such as from 5 to 30 minutes, but may be carried out for shorter or longer periods of time dependent on the material to be pre-treated.
  • Other examples of suitable pre-treatment methods are described by Schell et al., 2003,
  • the cellulosic material preferably lignocellulosic material, is treated chemically and/or mechanically pre-treated.
  • mechanical pre-treatment refers to any mechanical or physical treatment which promotes the separation and/or release of cellulose, hemicellulose and/or lignin from lignocellulose-containing material.
  • mechanical pre-treatment includes various types of milling, irradiation, steaming/steam explosion, and hydrothermolysis.
  • Mechanical pre-treatment includes comminution (mechanical reduction of the particle size). Comminution includes dry milling, wet milling and vibratory ball milling.
  • Mechanical pre- treatment may involve high pressure and/or high temperature (steam explosion).
  • high pressure means pressure in the range from 300 to 600 psi, preferably 400 to 500 psi, such as around 450 psi.
  • high temperature means temperatures in the range from about 100 to 300 0 C, preferably from about 140 to 235°C.
  • mechanical pre-treatment is a batch-process, steam gun hydrolyzer system which uses high pressure and high temperature as defined above.
  • a Sunds Hydrolyzer (available from Sunds Defibrator AB (Sweden) may be used for this.
  • both chemical and mechanical pre-treatment is carried out involving, for example, both dilute or mild acid treatment and high temperature and pressure treatment.
  • the chemical and mechanical pre-treatment may be carried out sequentially or simultaneously, as desired.
  • the lignocellulose-containing material is subjected to both chemical and mechanical pre-treatment to promote the separation and/or release of cellulose, hemicellulose and/or lignin.
  • pre-treatment is carried out as a dilute and/or mild acid steam explosion step.
  • pre-treatment is carried out as an ammonia fiber explosion step (or AFEX pre-treatment step).
  • biological pre-treatment refers to any biological pre-treatment which promotes the separation and/or release of cellulose, hemicellulose, and/or lignin from the lignocellulose-containing material.
  • Biological pre- treatment techniques can involve applying lignin-solubilizing microorganisms (see, for example, Hsu, 1996, Pretreatment of biomass, in Handbook on Bioethanol: Production and Utilization, Wyman, C. E., ed., Taylor & Francis, Washington, DC, 179-212; Ghosh and Singh, 1993, Physicochemical and biological treatments for enzymatic/microbial conversion of lignocellulosic biomass, Adv. Appl. Microbiol.
  • the pre-treated lignocellulose-containing material may be hydrolyzed in order to break the lignin seal and disrupt the crystalline structure of cellulose.
  • hydrolysis is carried out enzymatically.
  • the pre-treated lignocellulose-containing material, to be fermented may be hydrolyzed by one or more hydrolases (class EC 3 according to the Enzyme Nomenclature), preferably one or more carbohydrases selected from the group consisting of cellulase, hemicellulase, or amylase, such as alpha-amylase, maltogenic amylase or beta-amylase.
  • a protease may also be present.
  • the enzyme(s) used for hydrolysis is(are) capable of directly or indirectly converting carbohydrate polymers into fermentable sugars, such as glucose and/or maltose, which can be fermented into a desired fermentation product, such as ethanol.
  • the carbohydrase has cellulolytic enzyme activity. Suitable carbohydrases are described in the "Enzymes" section below.
  • Hemicellulose polymers can be broken down by hemicellulases and/or acid hydrolysis to release its five and six carbon sugar components.
  • the six carbon sugars (hexoses) such as glucose, galactose and mannose, can readily be fermented to, e.g., ethanol, acetone, butanol, glycerol, citric acid, fumaric acid etc. by suitable fermenting organisms including yeast.
  • Preferred for ethanol fermentation is yeast of the species Saccharomyces cerevisiae, preferably strains which are resistant towards high levels of ethanol, i.e., up to, e.g., about 10, 12 or 15 vol. % or more ethanol.
  • the pre-treated lignocellulose-containing material is hydrolyzed using a hemicellulase, preferably a xylanase, esterase, cellobiase, or combination thereof.
  • Hydrolysis may also be carried out in the presence of a combination of hemicellulases and/or cellulases, and optionally one or more of the other enzyme activities mentioned above.
  • the enzymatic treatment may be carried out in a suitable aqueous environment under conditions which can readily be determined by one skilled in the art.
  • hydrolysis is carried out at optimal conditions for the enzyme(s) in question.
  • Suitable process time, temperature and pH conditions can readily be determined by one skilled in the art present invention.
  • hydrolysis is carried out at a temperature between 30 and 70 0 C, preferably between 40 and 60 0 C, especially around 50°C.
  • the process is preferably carried out at a pH in the range from 3-8, preferably pH 4-6, especially around pH 5.
  • hydrolysis is carried out for between 8 and 72 hours, preferably between 12 and 48 hours, especially around 24 hours.
  • Fermentation of lignocellulose-containing material may be carried out in accordance with a fermentation process of the invention as described above.
  • hydrolysis in step (b) and fermentation in step (c) may be carried out simultaneously (SSF process) or sequentially (SHF process).
  • Hydrolysis and fermentation may be carried out as a simultaneous hydrolysis and fermentation step (SSF).
  • SSF simultaneous hydrolysis and fermentation step
  • the hydrolysis step and fermentation step may be carried out as hybrid hydrolysis and fermentation (HHF).
  • HHF typically begins with a separate partial hydrolysis step and ends with a simultaneous hydrolysis and fermentation step.
  • the separate partial hydrolysis step is an enzymatic cellulose saccharification step typically carried out at conditions (e.g., at higher temperatures) suitable, preferably optimal, for the hydrolyzing enzyme(s) in question.
  • the subsequent simultaneous hydrolysis and fermentation step is typically carried out at conditions suitable for the fermenting organism(s) (often at lower temperatures than the separate hydrolysis step).
  • hydrolysis and fermentation steps may also be carried out as separate hydrolysis and fermentation, where the hydrolysis is taken to completion before initiation of fermentation. This is often referred to as "SHF".
  • the fermentation product may optionally be separated from the fermentation medium in any suitable way.
  • the medium may be distilled to extract the fermentation product, or the fermentation product may be extracted from the fermentation medium by micro or membrane filtration techniques.
  • the fermentation product may be recovered by stripping. Recovery methods are well known in the art.
  • Fermentation Products The present invention may be used for producing any fermentation product.
  • Preferred fermentation products include alcohols (e.g., ethanol, methanol, butanol); organic acids (e.g., citric acid, acetic acid, itaconic acid, lactic acid, gluconic acid); ketones (e.g., acetone); amino acids (e.g., glutamic acid); gases (e.g., H 2 and CO 2 ); antibiotics (e.g., penicillin and tetracycline); enzymes; vitamins (e.g., riboflavin, B12, beta-carotene); and hormones.
  • alcohols e.g., ethanol, methanol, butanol
  • organic acids e.g., citric acid, acetic acid, itaconic acid, lactic acid, gluconic acid
  • ketones e.g., acetone
  • amino acids e.g., glutamic acid
  • gases e.g.,
  • the fermentation product is an alcohol, especially ethanol.
  • the fermentation product such as ethanol, obtained according to the invention, may preferably be used as fuel alcohol/ethanol. However, in the case of ethanol, it may also be used as potable ethanol.
  • Lignocellulose-containing material may be any material containing lignocellulose.
  • the lignocellulose-containing material contains at least 50 wt. %, preferably at least 70 wt-%, more preferably at least 90 wt-% lignocellulose. It is to be understood that the lignocellulose-containing material may also comprise other constituents such as cellulosic material, such as cellulose, hemicellulose, and may also comprise constituents such as sugars, such as fermentable sugars and/or un-fermentable sugars.
  • Lignocellulose-containing material is generally found, for example, in the stems, leaves, hulls, husks, and cobs of plants or leaves, branches, and wood of trees.
  • Lignocellulosic material can also be, but is not limited to, herbaceous material, agricultural residues, forestry residues, municipal solid wastes, waste paper, and pulp and paper mill residues. It is understood herein that lignocellulose-containing material may be in the form of plant cell wall material containing lignin, cellulose, and hemi-cellulose in a mixed matrix.
  • the lignocellulose-containing material is corn stover, corn cobs, corn fiber, rice straw, pine wood, wood chips, poplar, wheat straw, switchgrass, bagasse, paper and pulp processing waste.
  • the material is corn stover or corn cobs. In another preferred aspect, the material is corn fiber. Enzymes
  • an alpha-amylase may be used any alpha-amylase.
  • the alpha-amylase is an acid alpha-amylase, e.g., fungal acid alpha- amylase or bacterial acid alpha-amylase.
  • the term "acid alpha-amylase” means an alpha- amylase (E. C. 3.2.1.1 ) which added in an effective amount has activity optimum at a pH in the range of 3 to 7, preferably from 3.5 to 6, or more preferably from 4-5.
  • the bacterial alpha-amylase is preferably derived from the genus Bacillus.
  • Bacillus alpha-amylase is derived from a strain of B. licheniformis, B. amyloliquefaciens, B. subtilis or B. stearothermophilus, but may also be derived from other Bacillus sp.
  • contemplated alpha-amylases include the Bacillus licheniformis alpha-amylase shown in SEQ ID NO: 4 in WO 99/19467, the Bacillus amyloliquefaciens alpha-amylase SEQ ID NO: 5 in WO 99/19467 and the Bacillus stearothermophilus alpha-amylase shown in SEQ ID NO: 3 in WO 99/19467 (all sequences hereby incorporated by reference).
  • the alpha-amylase may be an enzyme having a degree of identity of at least 60%, preferably at least 70%, more preferred at least 80%, even more preferred at least 90%, such as at least 95%, at least 96%, at least 97%, at least 98% or at least 99% to any of the sequences shown in SEQ ID NO: 1 , 2 or 3, respectively, in WO 99/19467.
  • the Bacillus alpha-amylase may also be a variant and/or hybrid, especially one described in any of WO 96/23873, WO 96/23874, WO 97/41213, WO 99/19467, WO 00/60059, and WO 02/10355 (all documents hereby incorporated by reference).
  • WO 96/23873 WO 96/23874
  • WO 97/41213 WO 99/19467
  • WO 00/60059 WO 02/10355
  • Specifically contemplated alpha-amylase variants are disclosed in U.S. Patent Nos. 6,093,562, 6,297,038 or U.S. Patent No.
  • BSG alpha-amylase Bacillus stearothermophilus alpha-amylase (BSG alpha-amylase) variants having a deletion of one or two amino acid in positions R179 to G182, preferably a double deletion disclosed in WO 1996/023873 - see e.g., page 20, lines 1-10 (hereby incorporated by reference), preferably corresponding to delta(181-182) compared to the wild-type BSG alpha-amylase amino acid sequence set forth in SEQ ID NO: 3 disclosed in WO 99/19467 or deletion of amino acids R179 and G180 using SEQ ID NO: 3 in WO 99/19467 for numbering (which reference is hereby incorporated by reference).
  • BSG alpha-amylase Bacillus stearothermophilus alpha-amylase
  • Bacillus alpha- amylases especially Bacillus stearothermophilus alpha-amylase, which have a double deletion corresponding to delta(181-182) and further comprise a N193F substitution (also denoted 1181 * + G182 * + N193F) compared to the wild-type BSG alpha-amylase amino acid sequence set forth in SEQ ID NO: 3 disclosed in WO 99/19467.
  • a hybrid alpha-amylase specifically contemplated comprises 445 C-terminal amino acid residues of the Bacillus licheniformis alpha-amylase (shown in SEQ ID NO: 4 of WO 99/19467) and the 37 N-terminal amino acid residues of the alpha-amylase derived from
  • Bacillus amyloliquefaciens (shown in SEQ ID NO: 5 of WO 99/19467), with one or more, especially all, of the following substitution:
  • Bacillus alpha-amylase backbones H154Y, A181T, N190F, A209V and Q264S and/or deletion of two residues between positions 176 and 179, preferably deletion of E178 and
  • G179 (using SEQ ID NO: 5 numbering of WO 99/19467).
  • the bacterial alpha-amylase is dosed in an amount of 0.0005-5 KNU per g DS (dry solids), preferably 0.001-1 KNU per g DS, such as around 0.050 KNU per g DS.
  • Fungal alpha-amylases include alpha-amylases derived from a strain of the genus Aspergillus, such as, Aspergillus oryzae, Aspergillus niger and Aspergillis kawachii alpha- amylases.
  • a preferred acidic fungal alpha-amylase is a Fungamyl-like alpha-amylase which is derived from a strain of Aspergillus oryzae.
  • the term "Fungamyl-like alpha-amylase” indicates an alpha-amylase which exhibits a high identity, i.e., more than 70%, more than 75%, more than 80%, more than 85% more than 90%, more than 95%, more than 96%, more than 97%, more than 98%, more than 99% or even 100% identity to the mature part of the amino acid sequence shown in SEQ ID NO: 10 in WO 96/23874.
  • Another preferred acidic alpha-amylase is derived from a strain Aspergillus niger.
  • the acid fungal alpha-amylase is the one from A. niger disclosed as
  • wild-type alpha-amylases include those derived from a strain of the genera Rhizomucor and Meripilus, preferably a strain of Rhizomucor pusillus (WO 2004/055178 incorporated by reference) or Meripilus giganteus.
  • the alpha-amylase is derived from Aspergillus kawachii and disclosed by Kaneko et al., 1996, J. Ferment. Bioeng. 81 : 292-298, "Molecular-cloning and determination of the nucleotide-sequence of a gene encoding an acid-stable alpha- amylase from Aspergillus kawachir; and further as EMBL:#AB008370.
  • the fungal alpha-amylase may also be a wild-type enzyme comprising a starch- binding domain (SBD) and an alpha-amylase catalytic domain (i.e., non-hybrid), or a variant thereof.
  • SBD starch- binding domain
  • alpha-amylase catalytic domain i.e., non-hybrid
  • the wild-type alpha-amylase is derived from a strain of Aspergillus kawachii.
  • the fungal acid alpha-amylase is a hybrid alpha-amylase.
  • a hybrid alpha-amylase may comprise an alpha-amylase catalytic domain (CD) and a carbohydrate-binding domain/module (CBM), such as a starch binding domain, and optional a linker.
  • CD alpha-amylase catalytic domain
  • CBM carbohydrate-binding domain/module
  • contemplated hybrid alpha-amylases include those disclosed in Table 1 to 5 of the examples in U.S. application no. 60/638,614, including Fungamyl variant with catalytic domain JA118 and Athelia rolfsii SBD (SEQ ID NO:100 in US 60/638,614), Rhizomucor pusillus alpha-amylase with Athelia rolfsii AMG linker and SBD (SEQ ID NO:101 in US 60/638,614), Rhizomucor pusillus alpha-amylase with Aspergillus niger glucoamylase linker and SBD (which is disclosed in Table 5 as a combination of amino acid sequences SEQ ID NO: 20, SEQ ID NO: 72 and SEQ ID NO: 96 in U.S.
  • alpha-amylases which exhibit a high identity to any of above mention alpha-amylases, i.e., more than 70%, more than 75%, more than 80%, more than 85% more than 90%, more than 95%, more than 96%, more than 97%, more than 98%, more than 99% or even 100% identity to the mature enzyme sequences.
  • An acid alpha-amylases may according to the invention be added in an amount of 0.1 to 10 AFAU/g DS, preferably 0.10 to 5 AFAU/g DS, especially 0.3 to 2 AFAU/g DS or 0.001 to 1 FAU-F/g DS, preferably 0.01 to 1 FAU-F/g DS.
  • Preferred commercial compositions comprising alpha-amylase include MYCOLASE from DSM (Gist Brocades), BANTM, TERMAMYLTM SC, FUNGAMYLTM, LIQUOZYMETM X and SANTM SUPER, SANTM EXTRA L (Novozymes A/S) and CLARASETM L-40,000, DEX- LOTM, SPEZYMETM FRED, SPEZYMETM AA, SPEZYMETM DELTA AA, SPEZYME XTRATM (Genencor Int., USA), FUELZYMETM (from Verenium Corp, USA) and the acid fungal alpha- amylase sold under the trade name SP288 (available from Novozymes A/S, Denmark).
  • carbohydrate-source generating enzyme includes glucoamylase (being glucose generators), beta-amylase and maltogenic amylase (being maltose generators).
  • a carbohydrate-source generating enzyme is capable of producing a carbohydrate that can be used as an energy-source by the fermenting organism(s) in question, for instance, when used in a process of the invention for producing a fermentation product, such as ethanol.
  • the generated carbohydrate may be converted directly or indirectly to the desired fermentation product, preferably ethanol.
  • a mixture of carbohydrate-source generating enzymes may be used.
  • mixtures are mixtures of at least a glucoamylase and an alpha-amylase, especially an acid amylase, even more preferred an acid fungal alpha-amylase.
  • the ratio between acid fungal alpha- amylase activity (AFAU) per glucoamylase activity (AGU) (AFAU per AGU) may in an embodiment of the invention be at least 0.1 , or at least 0.16, such as in the range from 0.12 to 0.50 or more.
  • the ratio between acid fungal alpha-amylase activity (FAU-F) and glucoamylase activity (AGU) may in an embodiment of the invention be between 0.1 and 100, in particular between 2 and 50, such as in the range from 10-40.
  • a glucoamylase used according to the invention may be derived from any suitable source, e.g., derived from a microorganism or a plant.
  • Preferred glucoamylases are of fungal or bacterial origin, selected from the group consisting of Aspergillus glucoamylases, in particular A. niger G ⁇ or G2 glucoamylase (Boel et al., 1984, EMBO J. 3 (5): 1097-1 102), or variants thereof, such as those disclosed in WO 92/00381 , WO 00/04136 and WO 01/04273 (from Novozymes, Denmark); the A.
  • awamori glucoamylase disclosed in WO 84/02921 , A. oryzae glucoamylase (Agric. Biol. Chem., 1991 , 55 (4): 941-949), or variants or fragments thereof.
  • Other Aspergillus glucoamylase variants include variants with enhanced thermal stability: G137A and G139A (Chen et al., 1996, Prot. Eng. 9: 499-505); D257E and D293E/Q (Chen et al., 1995, Prot. Eng. 8: 575-582); N182 (Chen et al., 1994, Biochem. J.
  • glucoamylases include Athelia rolfsii (previously denoted Corticium rolfsii) glucoamylase (see U.S. Patent No. 4,727,026 and Nagasaka et al., 1998, "Purification and properties of the raw-starch-degrading glucoamylases from Corticium rolfsii, Appl Microbiol Biotechnol 50:323-330), Talaromyces glucoamylases, in particular derived from Talaromyces emersonii (WO 99/28448), Talaromyces leycettanus (U.S. Patent No. Re.
  • Bacterial glucoamylases contemplated include glucoamylases from the genus
  • Clostridium in particular C. thermoamylolyticum (EP 135,138), and C. thermohydrosulfuricum (WO 86/01831 ) and Trametes cingulata disclosed in WO 2006/069289 (which is hereby incorporated by reference).
  • hybrid glucoamylases are contemplated according to the invention.
  • Examples of hybrid glucoamylases are disclosed in WO 2005/045018. Specific examples include the hybrid glucoamylases disclosed in Tables 1 and 4 of Example 1 (which hybrids are hereby incorporated by reference.).
  • glucoamylases which exhibit a high identity to any of above mention glucoamylases, i.e., more than 70%, more than 75%, more than 80%, more than 85% more than 90%, more than 95%, more than 96%, more than 97%, more than 98%, more than 99% or even 100% identity to the mature enzymes sequences.
  • compositions comprising glucoamylase include AMG 200L; AMG 300 L; SANTM SUPER, SANTM EXTRA L, SPIRIZYMETM PLUS, SPIRIZYMETM FUEL, SPIRIZYMETM B4U, SPIRIZYME ULTRATM and AMGTM E (from Novozymes A/S, Denmark); OPTIDEXTM 300, GC480TM and GC147TM (from Genencor Int., USA); AMIGASETM and AMIGASETM PLUS (from DSM); G-ZYMETM G900, G-ZYMETM and G990 ZR (from Genencor Int.).
  • Glucoamylases may in an embodiment be added in an amount of 0.02-20 AGU/g DS, preferably 0.1-10 AGU/g DS, especially between 1-5 AGU/g DS, such as 0.1-2 AGU/g DS, such as 0.5 AGU/g DS or in an amount of 0.0001-20 AGU/g DS, preferably 0.001-10 AGU/g DS, especially between 0.01-5 AGU/g DS, such as 0.1-2 AGU/g DS.
  • the a beta-amylase (E. C 3.2.1.2) is the name traditionally given to exo-acting maltogenic amylases, which catalyze the hydrolysis of 1 ,4- alpha-glucosidic linkages in amylose, amylopectin and related glucose polymers. Maltose units are successively removed from the non-reducing chain ends in a step-wise manner until the molecule is degraded or, in the case of amylopectin, until a branch point is reached.
  • the maltose released has the beta anomeric configuration, hence the name beta-amylase.
  • Beta-amylases have been isolated from various plants and microorganisms (W. M. Fogarty and CT. Kelly, 1979, Progress in Industrial Microbiology 15: 1 12-1 15). These beta- amylases are characterized by having optimum temperatures in the range from 40 0 C to 65°C and optimum pH in the range from 4.5 to 7.
  • a commercially available beta-amylase from barley is NOVOZYMTM WBA from Novozymes A/S, Denmark and SPEZYMETM BBA 1500 from Genencor Int., USA.
  • the amylase may also be a maltogenic alpha-amylase.
  • a "maltogenic alpha- amylase” (glucan 1 ,4-alpha-maltohydrolase, E. C. 3.2.1.133) is able to hydrolyze amylose and amylopectin to maltose in the alpha-configuration.
  • a maltogenic amylase from Bacillus stearothermophilus strain NCIB 11837 is commercially available from Novozymes A/S. Maltogenic alpha-amylases are described in U.S. Patent Nos. 4,598,048, 4,604,355 and 6,162,628, which are hereby incorporated by reference.
  • the maltogenic amylase may in a preferred embodiment be added in an amount of 0.05- 5 mg total protein/gram DS or 0.05- 5 MANU/g DS.
  • the protease may be any protease, such as of microbial or plant origin.
  • the protease is an acid protease of microbial origin, preferably of fungal or bacterial origin.
  • Suitable proteases include microbial proteases, such as fungal and bacterial proteases.
  • Preferred proteases are acidic proteases, i.e., proteases characterized by the ability to hydrolyze proteins under acidic conditions below pH 7.
  • Contemplated acid fungal proteases include fungal proteases derived from Aspergillus, Mucor, Rhizopus, Candida, Coriolus, Endothia, Enthomophtra, Irpex, Penicillium, Sclerotiumand Torulopsis.
  • proteases derived from Aspergillus niger see, e.g., Koaze et al., 1964, Agr. Biol. Chem. Japan 28: 216), Aspergillus saitoi (see, e.g., Yoshida, 1954, J. Agr. Chem. Soc. Japan 28: 66), Aspergillus awamori (Hayashida et al., 1977, Agric.
  • proteases such as a protease derived from a strain of Bacillus.
  • a particular protease contemplated for the invention is derived from Bacillus amyloliquefaciens and has the sequence obtainable at Swissprot as Accession No. P06832.
  • the proteases having at least 90% identity to amino acid sequence obtainable at Swissprot as Accession No. P06832 such as at least 92%, at least 95%, at least 96%, at least 97%, at least 98%, or particularly at least 99% identity.
  • proteases having at least 90% identity to amino acid sequence disclosed as SEQ. ID. NO: 1 in the WO 2003/048353 such as at 92%, at least 95%, at least 96%, at least 97%, at least 98%, or particularly at least 99% identity.
  • proteases within E. C. 3.4.22. * cyste protease
  • EC 3.4.22.2 papain
  • EC 3.4.22.6 chymopapain
  • EC 3.4.22.7 asclepain
  • EC 3.4.22.14 actinidain
  • EC 3.4.22.15 cathepsin L
  • EC 3.4.22.25 glycyl endopeptidase
  • EC 3.4.22.30 (caricain).
  • the protease is a protease preparation derived from a strain of
  • the protease is derived from a strain of Rhizomucor, preferably Rhizomucor miehei.
  • the protease is a protease preparation, preferably a mixture of a proteolytic preparation derived from a strain of Aspergillus, such as Aspergillus oryzae, and a protease derived from a strain of Rhizomucor, preferably Rhizomucor mehei.
  • Aspartic acid proteases are described in, for example, Handbook of Proteolytic Enzymes, Edited by Barrett, Rawlings and Woessner, Academic Press, San Diego, 1998, Chapter 270). Suitable examples of aspartic acid protease include, e.g., those disclosed in Berka et al., 1990, Gene 96: 313; Berka et al., 1993, Gene 125: 195-198; and Gomi et al., 1993, Biosci. Biotech. Biochem. 57: 1095-1100, which are hereby incorporated by reference.
  • the protease may be present in an amount of 0.0001-1 mg enzyme protein per g
  • the protease may be present in an amount of 0.0001 to 1 LAPU/g DS, preferably 0.001 to 0.1 LAPU/g DS and/or 0.0001 to 1 mAU-RH/g DS, preferably 0.001 to 0.1 mAU-RH/g DS or 0.1-1000 AU/kg DM (dry matter), preferably 1-100 AU/kg DS and most preferably 5-25 AU/kg DS.
  • cellulolytic enzymes as used herein are understood as comprising the cellobiohydrolases (EC 3.2.1.91 ), e.g., cellobiohydrolase I and cellobiohydrolase II, as well as the endo-glucanases (EC 3.2.1.4) and beta-glucosidases (EC 3.2.1.21 ). See relevant sections below with further description of such enzymes.
  • cellulose In order to be efficient, the digestion of cellulose may require several types of enzymes acting cooperatively. At least three categories of enzymes are often needed to convert cellulose into glucose: endoglucanases (EC 3.2.1.4) that cut the cellulose chains at random; cellobiohydrolases (EC 3.2.1.91 ) which cleave cellobiosyl units from the cellulose chain ends and beta-glucosidases (EC 3.2.1.21 ) that convert cellobiose and soluble cellodextrins into glucose.
  • endoglucanases EC 3.2.1.91
  • beta-glucosidases EC 3.2.1.21
  • cellobiohydrolases are the key enzymes for the degradation of native crystalline cellulose.
  • cellobiohydrolase I is defined herein as a cellulose 1 ,4-beta-cellobiosidase (also referred to as Exo-glucanase, Exo-cellobiohydrolase or 1 ,4- beta-cellobiohydrolase) activity, as defined in the enzyme class EC 3.2.1.91 , which catalyzes the hydrolysis of 1 ,4-beta-D-glucosidic linkages in cellulose and cellotetraose, by the release of cellobiose from the non-reducing ends of the chains.
  • the definition of the term “cellobiohydrolase Il activity” is identical, except that cellobiohydrolase Il attacks from the reducing ends of the chains.
  • the cellulolytic enzymes may comprise a carbohydrate-binding module (CBM) which enhances the binding of the enzyme to a cellulose-containing fiber and increases the efficacy of the catalytic active part of the enzyme.
  • CBM is defined as contiguous amino acid sequence within a carbohydrate-active enzyme with a discreet fold having carbohydrate-binding activity.
  • the cellulolytic enzymes may be a cellulolytic preparation as defined in co-pending international application PCT/US2008/065417, which is hereby incorporated by reference.
  • the cellulolytic preparation comprising a polypeptide having cellulolytic enhancing activity (GH61A), preferably the one disclosed in WO 2005/074656.
  • the cellulolytic preparation may further comprise a beta-glucosidase, such as a beta-glucosidase derived from a strain of the genus Trichoderma, Aspergillus or Penicillium, including the fusion protein having beta-glucosidase activity disclosed in WO 2008/057637 (Novozymes).
  • the cellulolytic preparation may also comprises a CBH II, preferably Thielavia terrestris cellobiohydrolase Il (CEL6A).
  • CEL6A Thielavia terrestris cellobiohydrolase Il
  • the cellulolytic preparation also comprises a cellulase enzymes preparation, preferably the one derived from Trichoderma reesei.
  • the cellulolytic activity may, in a preferred embodiment, be derived from a fungal source, such as a strain of the genus Trichoderma, preferably a strain of Trichoderma reesei; or a strain of the genus Humicola, such as a strain of Humicola insolens; or a strain of Chrysosporium, preferably a strain of Chrysosporium lucknowense (see e.g., US publication # 2007/0238155 from Dyadic Inc, USA).
  • a fungal source such as a strain of the genus Trichoderma, preferably a strain of Trichoderma reesei; or a strain of the genus Humicola, such as a strain of Humicola insolens; or a strain of Chrysosporium, preferably a strain of Chrysosporium lucknowense (see e.g., US publication # 2007/0238155 from Dyadic Inc, USA).
  • the cellulolytic enzyme preparation comprises a polypeptide having cellulolytic enhancing activity (GH61A) disclosed in WO 2005/074656; a cellobiohydrolase, such as Thielavia terrestris cellobiohydrolase Il (CEL6A), a beta- glucosidase (e.g., the fusion protein disclosed in WO 2008/057637) and cellulolytic enzymes, e.g., derived from Trichoderma reesei.
  • G61A cellulolytic enhancing activity
  • CEL6A Thielavia terrestris cellobiohydrolase Il
  • beta- glucosidase e.g., the fusion protein disclosed in WO 2008/057637
  • cellulolytic enzymes e.g., derived from Trichoderma reesei.
  • the cellulolytic enzyme preparation comprises a polypeptide having cellulolytic enhancing activity (GH61A) disclosed in WO 2005/074656; a beta- glucosidase (e.g., the fusion protein disclosed in WO 2008/057637) and cellulolytic enzymes, e.g., derived from Trichoderma reesei.
  • G61A cellulolytic enhancing activity
  • beta- glucosidase e.g., the fusion protein disclosed in WO 2008/057637
  • cellulolytic enzymes e.g., derived from Trichoderma reesei.
  • the cellulolytic enzyme is the commercially available product CELLUCLAST® 1.5L or CELLUZYMETM available from Novozymes A/S, Denmark.
  • a cellulolytic enzymes may be added for hydrolyzing the pre-treated lignocellulose- containing material.
  • the cellulase may be dosed in the range from 0.1-100 FPU per gram total solids (TS), preferably 0.5-50 FPU per gram TS, especially 1-20 FPU per gram TS.
  • Endoglucanases catalyses endo hydrolysis of 1 ,4-beta-D-glycosidic linkages in cellulose, cellulose derivatives (such as carboxy methyl cellulose and hydroxy ethyl cellulose), lichenin, beta-1 ,4 bonds in mixed beta-1 ,3 glucans such as cereal beta-D- glucans or xyloglucans and other plant material containing cellulosic parts.
  • the authorized name is endo-1 ,4-beta-D-glucan 4-glucano hydrolase, but the abbreviated term endoglucanase is used in the present specification. Endoglucanase activity may be determined using carboxymethyl cellulose (CMC) hydrolysis according to the procedure of Ghose, 1987, Pure and Appl. Chem. 59: 257-268.
  • endoglucanases may be derived from a strain of the genus Trichoderma, preferably a strain of Trichoderma reesei; a strain of the genus Humicola, such as a strain of Humicola insolens; or a strain of Chrysosporium, preferably a strain of Chrysosporium lucknowense.
  • Cellobiohvdrolase CBH
  • cellobiohydrolase means a 1 ,4-beta-D-glucan cellobiohydrolase (E. C.
  • CBH I and CBH Il from Trichoderma reseei examples include CBH I and CBH Il from Trichoderma reseei; Humicola insolens and CBH Il from Thielavia terrestris cellobiohydrolase (CELL6A)
  • Cellobiohydrolase activity may be determined according to the procedures described by Lever et al., 1972, Anal. Biochem. 47: 273-279 and by van Tilbeurgh et al., 1982, FEBS
  • the Lever et al. method is suitable for assessing hydrolysis of cellulose in corn stover and the method of van Tilbeurgh et al. is suitable for determining the cellobiohydrolase activity on a fluorescent disaccharide derivative.
  • Beta-glucosidase One or more beta-glucosidases (often referred to as “cellobiases”) may be present during hydrolysis.
  • the term "beta-glucosidase” means a beta-D-glucoside glucohydrolase (E. C. 3.2.1.21 ), which catalyzes the hydrolysis of terminal non-reducing beta-D-glucose residues with the release of beta-D-glucose.
  • beta-glucosidase activity is determined according to the basic procedure described by Venturi et al., 2002, J. Basic Microbiol. 42: 55-66, except different conditions were employed as described herein.
  • beta-glucosidase activity is defined as 1.0 ⁇ mole of p-nitrophenol produced per minute at 50 0 C, pH 5 from 4 mM p-nitrophenyl-beta-D-glucopyranoside as substrate in 100 mM sodium citrate, 0.01 % TWEEN® 20.
  • beta-glucosidase is of fungal origin, such as a strain of the genus Trichoderma, Aspergillus or Penicillium.
  • the beta- glucosidase is a derived from Trichoderma reesei, such as the beta-glucosidase encoded by the bgl1 gene (see Fig. 1 of EP 562003).
  • beta- glucosidase is derived from Aspergillus oryzae (recombinantly produced in Aspergillus oryzae according to WO 02/095014), Aspergillus fumigatus (recombinantly produced in Aspergillus oryzae according to Example 22 of WO 02/095014) or Aspergillus niger (1981 , J. Appl. 3: 157-163).
  • the beta-glucosidase is the fusion protein disclosed in WO 2008/057637 (Novozymes).
  • cellulolytic enhancing activity is defined herein as a biological activity that enhances the hydrolysis of a lignocellulose derived material by proteins having cellulolytic activity.
  • cellulolytic enhancing activity is determined by measuring the increase in reducing sugars or in the increase of the total of cellobiose and glucose from the hydrolysis of a lignocellulose derived material, e.g., pre-treated lignocellulose-containing material by cellulolytic protein under the following conditions: 1-50 mg of total protein/g of cellulose in PCS (pre-treated corn stover), wherein total protein is comprised of 80-99.5% w/w cellulolytic protein/g of cellulose in PCS and 0.5-20% w/w protein of cellulolytic enhancing activity for 1-7 day at 50 0 C compared to a control hydrolysis with equal total protein loading without cellulolytic enhancing activity (1-50 mg of cellulolytic protein/g of cellulose in PCS
  • the polypeptides having cellulolytic enhancing activity enhance the hydrolysis of a lignocellulose derived material catalyzed by proteins having cellulolytic activity by reducing the amount of cellulolytic enzyme required to reach the same degree of hydrolysis preferably at least 0.1 -fold, more at least 0.2-fold, more preferably at least 0.3-fold, more preferably at least 0.4-fold, more preferably at least 0.5-fold, more preferably at least 1-fold, more preferably at least 3-fold, more preferably at least 4-fold, more preferably at least 5- fold, more preferably at least 10-fold, more preferably at least 20-fold, even more preferably at least 30-fold, most preferably at least 50-fold, and even most preferably at least 100-fold.
  • hydrolysis and/or fermentation is carried out in the presence of a cellulolytic enzyme in combination with a polypeptide having enhancing activity.
  • a cellulolytic enzyme in combination with a polypeptide having enhancing activity.
  • the polypeptide having enhancing activity is a family
  • GH61A polypeptide discloses isolated polypeptides having cellulolytic enhancing activity and polynucleotides thereof from Thielavia terrestris.
  • WO 2005/074656 discloses an isolated polypeptide having cellulolytic enhancing activity and a polynucleotide thereof from Thermoascus aurantiacus.
  • U.S. Application Publication No. 2007/0077630 discloses an isolated polypeptide having cellulolytic enhancing activity and a polynucleotide thereof from Trichoderma reesei.
  • Hemicellulose can be broken down by hemicellulases and/or acid hydrolysis to release its five and six carbon sugar components.
  • the lignocellulose derived material may be treated with one or more hemicellulases.
  • hemicellulase suitable for use in hydrolyzing hemicellulose, preferably into xylose may be used.
  • Preferred hemicellulases include xylanases, arabinofuranosidases, acetyl xylan esterase, feruloyl esterase, glucuronidases, galactanase, endo-galactanase, mannases, endo or exo arabinases, exo-galactanses, pectinase, xyloglucanase, or mixtures of two or more thereof.
  • the hemicellulase for use in the present invention is an exo-acting hemicellulase, and more preferably, the hemicellulase is an exo-acting hemicellulase which has the ability to hydrolyze hemicellulose under acidic conditions of below pH 7, preferably pH 3-7.
  • An example of hemicellulase suitable for use in the present invention includes VISCOZYMETM (available from Novozymes A/S, Denmark).
  • the hemicellulase is a xylanase.
  • the xylanase may preferably be of microbial origin, such as of fungal origin (e.g., Trichoderma, Meripilus, Humicola, Aspergillus, Fusarium) or from a bacterium (e.g., Bacillus).
  • the xylanase is derived from a filamentous fungus, preferably derived from a strain of Aspergillus, such as Aspergillus aculeatus (preferably XyI Il disclosed in WO 1994/021785); or a strain of Humicola, preferably Humicola lanuginosa.
  • the xylanase may preferably be an endo-1 ,4-beta-xylanase, more preferably an endo-1 ,4-beta-xylanase of GH10 or GH11.
  • Examples of commercial xylanases include SHEARZYMETM and BIOFEED WHEATTM from Novozymes A/S, Denmark.
  • Arabinofuranosidase (EC 3.2.1.55) catalyzes the hydrolysis of terminal non-reducing alpha-L-arabinofuranoside residues in alpha-L-arabinosides.
  • Galactanase (EC 3.2.1.89), arabinogalactan endo-1 ,4-beta-galactosidase, catalyses the endohydrolysis of 1 ,4-D-galactosidic linkages in arabinogalactans.
  • Pectinase (EC 3.2.1.15) catalyzes the hydrolysis of 1 ,4-alpha-D-galactosiduronic linkages in pectate and other galacturonans.
  • Xyloglucanase catalyzes the hydrolysis of xyloglucan.
  • the hemicellulase may be added in an amount effective to hydrolyze hemicellulose, such as, in amounts from about 0.001 to 0.5 wt.-% of total solids (TS), more preferably from about 0.05 to 0.5 wt.-% of TS.
  • TS total solids
  • Xylanases may be added in amounts of 0.001-1.0 g/kg DM (dry matter) substrate, preferably in the amounts of 0.005-0.5 g/kg DM substrate, and most preferably from 0.05-0.10 g/kg DM substrate.
  • the invention relates to a composition
  • a composition comprising one or more TRP channel agonist compounds and one or more enzymes and/or one or more fermenting organisms.
  • TRP channel agonist compounds can be found above in the "TRP channel and TRP superfamily" section above.
  • the enzyme(s) is(are) one or more hydrolases (class EC 3 according to Enzyme Nomenclature) selected from the group consisting of cellulase, hemicellulase, endoglucanase, beta-glucosidase, cellobiohydrolase, xylanase, alpha- amylase, alpha-glucosidases, glucoamylase, and proteases, or a mixture thereof.
  • the composition may also comprise a fermenting organism, such as a yeast, or another fermenting organism mentioned in the "Fermenting Organism" section above.
  • the invention relates to the use of one or more TRP channel agonist compounds for propagating fermenting organisms such as yeast.
  • invention also relates to the use of one or more TRP channel agonist compounds in a fermentation process, preferably a process of the invention.
  • Identity The relatedness between two amino acid sequences or between two nucleotide sequences is described by the parameter "identity”.
  • the degree of identity between two amino acid sequences is determined using the Needleman-Wunsch algorithm (Needleman and Wunsch, 1970, J. MoI. Biol. 48: 443-453) as implemented in the Needle program of the EMBOSS package (EMBOSS: The European Molecular Biology Open Software Suite, Rice et al., 2000, Trends in Genetics 16: 276-277), preferably version 3.0.0 or later.
  • the optional parameters used are gap open penalty of 10, gap extension penalty of 0.5, and the EBLOSUM62 (EMBOSS version of BLOSUM62) substitution matrix.
  • the output of Needle labeled "longest identity" (obtained using the -nobrief option) is used as the percent identity and is calculated as follows:
  • the degree of identity between two deoxyribonucleotide sequences is determined using the Needleman-Wunsch algorithm (Needleman and Wunsch, 1970, supra) as implemented in the Needle program of the EMBOSS package (EMBOSS: The European Molecular Biology Open Software Suite, Rice et al., 2000, supra), preferably version 3.0.0 or later.
  • the optional parameters used are gap open penalty of 10, gap extension penalty of 0.5, and the EDNAFULL (EMBOSS version of NCBI NUC4.4) substitution matrix.
  • the output of Needle labeled "longest identity" (obtained using the -nobrief option) is used as the percent identity and is calculated as follows:
  • the Novo Glucoamylase Unit is defined as the amount of enzyme, which hydrolyzes 1 micromole maltose per minute under the standard conditions 37°C, pH 4.3, substrate: maltose 23.2 mM, buffer: acetate 0.1 M, reaction time 5 minutes.
  • An autoanalyzer system may be used. Mutarotase is added to the glucose dehydrogenase reagent so that any alpha-D-glucose present is turned into beta-D-glucose. Glucose dehydrogenase reacts specifically with beta-D-glucose in the reaction mentioned above, forming NADH which is determined using a photometer at 340 nm as a measure of the original glucose concentration.
  • KNU Alpha-amylase activity
  • the alpha-amylase activity may be determined using potato starch as substrate. This method is based on the break-down of modified potato starch by the enzyme, and the reaction is followed by mixing samples of the starch/enzyme solution with an iodine solution. Initially, a blackish-blue color is formed, but during the break-down of the starch the blue color gets weaker and gradually turns into a reddish-brown, which is compared to a colored glass standard.
  • KNU One Kilo Novo alpha amylase Unit
  • AFAU Acid alpha-amylase activity
  • the activity of an acid alpha-amylase may be measured in FAU-F (Rjngal Alpha-Amylase ]Jnit) or AFAU (Acid Fungal Alpha- amylase Units).
  • FAU-F Fungal Alpha-Amylase LJnits (Fungamyl) is measured relative to an enzyme standard of a declared strength.
  • AFAU Acid alpha-amylase activity
  • Acid alpha-amylase activity may be measured in AFAU (Acid Fungal Alpha-amylase Units), which are determined relative to an enzyme standard. 1 AFAU is defined as the amount of enzyme which degrades 5.260 mg starch dry matter per hour under the below mentioned standard conditions.
  • Acid alpha-amylase an endo-alpha-amylase (1 ,4-alpha-D-glucan-glucanohydrolase, E. C. 3.2.1.1 ) hydrolyzes alpha-1 ,4-glucosidic bonds in the inner regions of the starch molecule to form dextrins and oligosaccharides with different chain lengths.
  • the intensity of color formed with iodine is directly proportional to the concentration of starch.
  • Amylase activity is determined using reverse colorimetry as a reduction in the concentration of starch under the specified analytical conditions.
  • Iodine (I2) 0.03 g/L
  • a rolled filter paper strip (#1 Whatman; 1 X 6 cm; 50 mg) is added to the bottom of a test tube (13 X 100 mm).
  • Enzyme dilutions are designed to produce values slightly above and below the target value of 2.0 mg glucose.
  • a reagent blank is prepared by adding 1.5 ml. of citrate buffer to a test tube.
  • a substrate control is prepared by placing a rolled filter paper strip into the bottom of a test tube, and adding 1.5 ml. of citrate buffer.
  • Enzyme controls are prepared for each enzyme dilution by mixing 1.0 ml. of citrate buffer with 0.5 ml. of the appropriate enzyme dilution.
  • each tube is diluted by adding 50 microL from the tube to 200 microL of ddH 2 O in a
  • a glucose standard curve is prepared by graphing glucose concentration (mg/0.5 mL) for the four standards (G1-G4) vs. A 540 . This is fitted using a linear regression (Prism Software), and the equation for the line is used to determine the glucose produced for each of the enzyme assay tubes.
  • the proteolytic activity may be determined with denatured hemoglobin as substrate.
  • Anson-Hemoglobin method for the determination of proteolytic activity denatured hemoglobin is digested, and the undigested hemoglobin is precipitated with trichloroacetic acid (TCA).
  • TCA trichloroacetic acid
  • the amount of TCA soluble product is determined with phenol reagent, which gives a blue color with tyrosine and tryptophan.
  • One Anson Unit is defined as the amount of enzyme which under standard conditions (i.e., 25°C, pH 5.5 and 10 min. reaction time) digests hemoglobin at an initial rate such that there is liberated per minute an amount of TCA soluble product which gives the same color with phenol reagent as one milliequivalent of tyrosine.
  • the AU(RH) method is described in EAL-SM-0350 and is available from Novozymes
  • the proteolytic activity may be determined with denatured hemoglobin as substrate.
  • denatured hemoglobin is digested, and the undigested hemoglobin is precipitated with trichloroacetic acid
  • TCA TCA soluble product
  • One Anson Unit is defined as the amount of enzyme which under standard conditions (i.e., 25°C, pH 7.5 and 10 min. reaction time) digests hemoglobin at an initial rate such that there is liberated per minute an amount of TCA soluble product which gives the same color with phenol reagent as one milliequivalent of tyrosine.
  • LAPU Protease assay method
  • LAPU 1 Leucine Amino Peptidase Unit
  • LAPU is described in EB-SM-0298.02/01 available from Novozymes A/S Denmark on request.
  • One MANU JVjaltogenic Amylase NJovo LJnit
  • MANU JVjaltogenic Amylase NJovo LJnit
  • Yeast / Peptone Media YP media was prepared by dissolving 20 grams per liter glucose, 10 grams per liter xylose,
  • Yeasts were propagated overnight in YP media. The yeasts were dosed into the fermentations at a pitch of 0.25 g cells per liter.
  • Cellulase preparation A Cellulolytic composition comprising a polypeptide having cellulolytic enhancing activity (GH61A) disclosed in WO 2005/074656; a beta-glucosidase (fusion protein disclosed in WO 2008/057637) and cellulolytic enzymes preparation derived from Trichoderma reesei. Cellulase preparation A is disclosed in co-pending application
  • PCS Unwashed pre-treated corn stover
  • Glucoamylase (AMG A): Glucoamylase derived from Trametes cingulata disclosed in SEQ ID NO:
  • Alpha-Amylase A (AA1 ): Hybrid alpha-amylase consisting of Rhizomucor pusillus alpha- amylase with Aspergillus niger glucoamylase linker and SBD disclosed as V039 in Table 5 in WO 2006/069290 (Novozymes A/S).
  • Vials were incubated at 32°C. Nine replicate fermentations of each treatment were run. Three replicates were selected for 24 hours, 48 hours and 70 hours time point analysis. Vials were vortexed at 24, 48 and 70 hours and analyzed by HPLC.
  • the HPLC preparation consisted of stopping the reaction by addition of 50 micro liters of 40% H 2 SO 4 , centrifuging, and filtering through a 0.45 micrometer filter. Samples were stored at 4°C until analysis.
  • AgilentTM 1 100 HPLC system coupled with Rl detector was used to determine ethanol and oligosaccharides concentration. The separation column was aminex HPX-87H ion exclusion column (300 mm x 7.8 mm) from BioRadTM. The results for Experiment 1 are summarized in Figure 1.
  • Dilute acid steam exploded corn stover was diluted with water and adjusted to pH 5.0 with NH 4 OH.
  • the total solids (TS) level was 20 wt.%.
  • This sample was then saccharified for 63 hours at 50 0 C with Cellulolytic Preparation A. Penicillin was added at a rate of 1 g/L, also added prior to saccharification was citrate buffer at a rate of 5OmL of 1 M citrate buffer per 100 ml of substrate.
  • the sample was filtered via a 0.2 micron Nalgene vacuum filter system (Product # 8-0000-43-0803) to remove the solids and used for fermentation.
  • the fuwPCS was then pipetted into separate sterile, 20 milliliter glass vials equipped with screw top lids fitted with a small CO 2 vent hole and 25 gauge needle.
  • capsaicin was diluted with DMSO.
  • the final dosages of capsaicin tested in the experiment were 10, 30, and 100 micromolar.
  • Fermentation vials were filled with 1.80 milliliters of 20% TS fuwPCS, 0.95 milliliters of YP media containing 70 grams per liter of glucose and 45 grams per liter of xylose, 150 microliters of yeast propagate, the appropriate amount (volume or weight) of the test compound, and sterile deionized water to a total final volume of 3.0 milliliters.
  • Fermentation vials were capped with screw-top lids with septa into which a 25 gauge needle was placed for CO 2 release. The vials were placed into a rack and inserted into a tabletop shaker and agitated at 150 rpm for 30 hours at a temperature of 30 0 C. All fermentations were run in triplicate. The control contained the same amount of DMSO as the treated samples. Analysis

Landscapes

  • Organic Chemistry (AREA)
  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Zoology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Wood Science & Technology (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Microbiology (AREA)
  • General Chemical & Material Sciences (AREA)
  • Biotechnology (AREA)
  • Health & Medical Sciences (AREA)
  • Biochemistry (AREA)
  • Bioinformatics & Cheminformatics (AREA)
  • General Engineering & Computer Science (AREA)
  • General Health & Medical Sciences (AREA)
  • Genetics & Genomics (AREA)
  • Preparation Of Compounds By Using Micro-Organisms (AREA)

Abstract

The invention relates to processes of fermenting plant materials into desired fermentation products using a fermenting organism, wherein one or more TRP channel agonist compounds is present during fermentation.

Description

PROCESSES OF PRODUCING FERMENTATION PRODUCTS
TECHNICAL FIELD
The present invention relates to processes of fermenting plant derived materials into desired fermentation products. The invention also relates to processes of producing desired fermentation products from plant materials using a fermenting organism and compositions that can be used in such processes.
BACKGROUND A vast number of commercial products are today produced by fermentation, including alcohols (e.g., ethanol, methanol, butanol, 1 ,3-propanediol) and organic acids (e.g., citric acid, acetic acid, itaconic acid, lactic acid, gluconic acid, gluconate, lactic acid, succinic acid, 2,5-diketo-D-gluconic acid). Processes of producing fermentation products, such as ethanol, by fermentation of sugars provided by degradation of starch-containing and/or lignocellulose-containing material are known in the art.
However, production of fermentation products, such as ethanol, is still costly. Therefore, there is a need for providing processes that can boost the yield of the fermentation product and thereby reducing the production costs.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 : Effect of capsaicin on ethanol yield from combination of alpha-amylase and glucoamylase in one-step simultaneous saccharification and fermentation (SSF) process. Figure 2: Effect of capsaicin and icilin on ethanol yield from hydrolyzed PCS fermented with RED STAR™ yeast. Figure 3: Effect of capsaicin and icilin on ethanol yield from hydrolyzed PCS fermented with RWB218 yeast.
SUMMARY OF THE INVENTION
In the first aspect the invention relates to processes of fermenting sugars derived from plant material into a fermentation product using a fermenting organism, wherein one or more TRP channel agonists is present during fermentation.
In another aspect the invention relates to processes of producing a fermentation product from starch-containing material comprising the steps of: i) liquefying starch-containing material; ii) saccharifying the liquefied material; iii) fermenting with a fermenting organism; wherein fermentation is carried out in accordance with a fermentation process of the invention.
In another aspect the invention relates to processes of producing a fermentation product from starch-containing material, comprising the steps of: (a) saccharifying starch-containing material at a temperature below the initial gelatinization temperature of said starch-containing material;
(b) fermenting with a fermenting organism; wherein fermentation is carried out in accordance with a fermentation process of the invention. In another aspect the invention relates to processes of producing a fermentation product from sugars derived from lignocellulose-containing material, comprising the steps of:
(a) pre-treating lignocellulose-containing material;
(b) hydrolysing the material obtained in step (a); (c) fermenting using a fermenting organism; wherein fermentation is carried out in accordance with a fermentation process of the invention. In another aspect the invention relates to composition suitable for use in a process of the invention comprising one or more TRP channel agonist compounds and an enzyme and/or a fermenting organism. In another aspect the invention relates to the use of one or more TRP channel agonist compounds for propagating fermenting organisms and/or in fermentation processes.
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to processes of fermenting plant derived material into a desired fermentation product. The invention also provides processes for producing desired fermentation products from plant material using a fermenting organism. Finally the invention relates to compositions that can be used in such processes and to the use of TRP channel agonist compounds for propagation of fermenting organisms and/or fermentations.
The inventor found that when TRP channel agonist compounds are present during fermentation a higher ethanol yield is obtained compared to processes where no TRP channel agonist compounds are added and/or present. The yeast viability may also be improved. The
TRP channel agonist compounds only need to be present during fermentation in very low concentration in order to provide the advantageous effect.
According to the invention the starting material (i.e., substrate for the fermenting organism in question) may be sugars derived from the degradation of plant material or parts or constituents thereof. According to the invention the starting material (i.e., substrate for the fermenting organism in question) may be sugars derived from degradation of plant material or parts or constituents thereof.
In one embodiment the stating material is sugars derived from starch-containing material. In another embodiment the starting material is sugars derived from lignocellulose- containing material.
In the first aspect the invention relates to processes of fermenting plant material into a fermentation product using a fermenting organism, wherein one or more TRP channel agonist compounds is present during fermentation.
The TRP channel agonist compounds may be added before and/or during fermentation. In an embodiment the compounds are added to the fermentation medium. In an embodiment the compounds are present in the fermentation medium.
TRP channel and TRP Superfamily
The terms "TRP channel agonist compounds" and "TRP superfamily" are art- recognized terms well understood by one skilled in the art.
An "agonist" is generally a term used to describe a type of compound that binds and alters the activity of a receptor, in this case a TRP channel.
Transient receptor potential channel proteins or TRP channel proteins include a family of related ion channel proteins that are non-selectively permeable to ions, especially cat-ions, such as calcium and magnesium.
A group of these TRP channel proteins a referred to as the "TRP superfamily" and is divided into seven subfamilies encoded by at least 33 channel subunit genes:
TRPC (canonical) - associated with Focal segmental glomerulosclerosis; TRPV (vanilloid); TRPA (ankyrin);
TRPM (melastatin) - associated with Hypomagnesemia with secondary hypocalcemia;
TRPP (polycystin) - associated with Polycystic kidney disease; TRPML (mucolipin) — associated with Mucolipidosis type IV; TRPN (NOMPC) - no mechanoreceptor potential C - not found in mammals.
The first is composed of the "classical" TRPs" (TRPC subfamily). Some TRPCs may be store-operated channels, whereas others appear to be activated by production of diacylglycerol or regulated through an exocytotic mechanism. Many members of a second subfamily (TRPV) function in sensory physiology and respond to heat, changes in osmolarity, odorants, and mechanical stimuli. Two members of the TRPM family function in sensory perception and three TRPM proteins are chanzymes, which contain C-terminal enzyme domains. The fourth and fifth subfamilies, TRPN and TRPA, include proteins with many ankyrin repeats. TRPN proteins function in mechanotransduction, whereas TRPA1 is activated by noxious cold and is also required for the auditory response. In addition to these five closely related TRP subfamilies, which comprise the Group 1 TRPs, members of the two Group 2 TRP subfamilies, TRPP and TRPML, are distantly related to the group 1 TRPs. Mutations in the founding members of these latter subfamilies are responsible for human diseases. Each of the TRP subfamilies are represented by members in worms and flies, providing the potential for using genetic approaches to characterize the normal functions and activation mechanisms of these channels. Examples of TRP channel agonist compounds include compounds selected from the group consisting of resiniferatoxin, piperine, olvanil, anadamide, 2-APB, camphor, 4alpha- PDD, 5'6'-EET, menthol, eucalyptol, icilin, cinnamaldehyde, allylisothiocyanate, delta9 tetra hydrocannabiol, and capsaicin, or analogues thereof.
In a preferred embodiment the TRP agonist compound is an agonist of a channel protein from the TRP superfamily TRPV.
In specific embodiments the TRP channel agonist compound is Capsaicin (8-methyl- Λ/-vanillyl-6-nonenamide). In another specific embodiment the TRP channel agonist compound is icilin.
The TRP channel agonist compound(s) may in an embodiment be of plant origin. Capsaicin is the component of chili peppers that is responsible for the "heat" or burning sensation. Chili peppers are plants belonging to the genus Capsicum.
The TRP channel agonist compound(s) may in another embodiment be synthetic.
Icilin is a synthetic agonist compound of the transient receptor potential M8 (TRPM8) channel. In a preferred embodiment an effective amount includes concentrations in the range from 0.01 mM-100 mM as determined by HPLC.
When TRP channel agonist compounds are present during fermentation the fermentation product yield may be boosted or increased. The concentration of the TRP channel agonist compound needed to obtain a fermentation yield increase is low, as indicated above. The viability of the yeast may also be increased by the presence of the TRP channel agonist compound. It is to be understood that according to the invention the concentration of the TRP channel agonist compounds are comparably higher than those concentrations when no such compounds are present or added. Fermenting Organisms
The term "fermenting organism" refers to any organism, including bacterial and fungal organisms, including yeast and filamentous fungi, suitable for producing a desired fermentation product. Especially suitable fermenting organisms according to the invention are able to ferment, i.e., convert sugars, such as glucose, fructose maltose, xylose, mannose and/or arabinose, directly or indirectly into the desired fermentation product. Examples of fermenting organisms include fungal organisms, such as yeast. Preferred yeast includes strains of the genus Saccharomyces, in particular a strain of Saccharomyces cerevisiae or Saccharomyces uvarum; a strain of Pichia, in particular Pichia stipitis or Pichia pastoήs; a strain of the genus Candida, in particular a strain of Candida utilis, Candida arabinofermentans, Candida diddensii, Candida sonorensis, Candida shehatae, Candida tropicalis, or Candida boidinii. Other contemplated yeast includes strains of Hansenula, in particular Hansenula polymorpha or Hansenula anomala; strains of Kluyveromyces, in particular Kluyveromyces marxianus or Kluyveromyces fagilis, and strains of Schizosaccharomyces, in particular Schizosaccharomyces pombe.
Preferred bacterial fermenting organisms include strains of Escherichia, in particular Escherichia coli, strains of Zymomonas, in particular Zymomonas mobilis, strains of Zymobacter, in particular Zymobactor palmae, strains of Klebsiella in particular Klebsiella oxytoca, strains of Leuconostoc, in particular Leuconostoc mesenteroides, strains of Clostridium, in particular Clostridium butyricum, strains of Enterobacter, in particular Enterobacter aerogenes and strains of Thermoanaerobacter, in particular Thermoanaerobacter BG1 L1 (Appl. Microbiol. Biotech. 77: 61-86) and Thermoanarobacter ethanolicus, Thermoanaerobacter thermosaccharolyticum, or Thermoanaerobacter mathranii. Strains of Lactobacillus are also envisioned as are strains of Corynebacterium glutamicum R, Bacillus thermoglucosidaisus, and Geobacillus thermoglucosidasius.
In an embodiment the fermenting organism is a C6 sugar fermenting organism, such as a strain of, e.g., Saccharomyces cerevisiae.
In connection with especially fermentation of lignocellulose derived material, C5 sugar fermenting organisms are contemplated. Most C5 sugar fermenting organisms also ferment C6 sugars. Examples of C5 sugar fermenting organisms include strains of Pichia, such as of the species Pichia stipitis. C5 sugar fermenting bacteria are also known. Also some Saccharomyces cerevisae strains ferment C5 (and C6) sugars. Examples are genetically modified strains of Saccharomyces spp. that are capable of fermenting C5 sugars include the ones concerned in, e.g., Ho et al., 1998, Applied and Environmental Microbiology, p. 1852- 1859 and Karhumaa et al., 2006, Microbial Cell Factories 5:18, and Kuyper et al., 2005, FEMS Yeast Research 5, p. 925-934. In one embodiment one or more fermenting organism(s) is(are) added to the fermentation medium so that the viable fermenting organism, such as yeast, count per ml_ of fermentation medium is in the range from 105 to 1012, preferably from 107 to 1010, especially about 5x107. Commercially available yeast includes, e.g., RED STAR™ and ETHANOL RED™ yeast (available from Fermentis/Lesaffre, USA), FALI (available from Fleischmann's Yeast, USA), SUPERSTART and THERMOSACC™ fresh yeast (available from Ethanol Technology, Wl, USA), BIOFERM AFT and XR (available from NABC - North American Bioproducts Corporation, GA, USA), GERT STRAND (available from Gert Strand AB, Sweden), and FERMIOL (available from DSM Specialties).
According to the invention the fermenting organism capable of producing a desired fermentation product from fermentable sugars, including glucose, fructose maltose, xylose, mannose, and/or arabinose, is preferably grown under precise conditions at a particular growth rate. When the fermenting organism is introduced into/added to the fermentation medium the inoculated fermenting organism pass through a number of stages. Initially growth does not occur. This period is referred to as the "lag phase" and may be considered a period of adaptation. During the next phase referred to as the "exponential phase" the growth rate gradually increases. After a period of maximum growth the rate ceases and the fermenting organism enters "stationary phase". After a further period of time the fermenting organism enters the "death phase" where the number of viable cells declines.
In one embodiment the TRP channel agonist compounds are added to the fermentation medium when the fermenting organism is in the lag phase.
In one embodiment the TRP channel agonist compounds are added to the fermentation medium when the fermenting organism is in exponential phase. In one embodiment the TRP channel agonist compounds are added to the fermentation medium when the fermenting organism is in stationary phase.
In one embodiment the TRP channel agonist compounds are added to the fermentation medium when the fermenting organism is in death phase.
Fermentation Products
The term "fermentation product" means a product produced by a process including a fermentation step using one or more fermenting organisms. Fermentation products contemplated according to the invention include alcohols (e.g., ethanol, methanol, butanol); organic acids (e.g., citric acid, acetic acid, itaconic acid, lactic acid, gluconic acid); ketones (e.g., acetone); amino acids (e.g., glutamic acid); gases (e.g., H2 and CO2); antibiotics (e.g., penicillin and tetracycline); enzymes; vitamins (e.g., riboflavin, B12, beta-carotene); and hormones. In a preferred embodiment the fermentation product is ethanol, e.g., fuel ethanol; drinking ethanol, i.e., potable neutral spirits; or industrial ethanol or products used in the consumable alcohol industry (e.g., beer and wine), dairy industry (e.g., fermented dairy products), leather industry and tobacco industry. Preferred beer types comprise ales, stouts, porters, lagers, bitters, malt liquors, happoushu, high-alcohol beer, low-alcohol beer, low-calorie beer or light beer. Preferred fermentation processes used include alcohol fermentation processes. The fermentation product, such as ethanol, obtained according to the invention, may preferably be used as fuel. However, in the case of ethanol it may also be used as potable ethanol.
Fermentation
The plant material used in a process of the invention may be starch-containing material or lignocellulose-containing material, or a combination thereof. The fermentation conditions are set based on, e.g., the kind of plant material, the fermentable sugars available, the fermenting organism(s) and/or the desired fermentation product. One skilled in the art can easily determine suitable fermentation conditions. The fermentation may according to one embodiment of the invention be carried out at conventionally used conditions. Preferred fermentation processes are according to the invention anaerobic.
Fermentation of Starch-derived Sugars
As mentioned above different kinds of fermenting organisms may be used for fermenting sugars derived from starch-containing material. Fermentations are conventionally carried out using yeast, such as Saccharomyces cerevisae, as the fermenting organism. However, bacteria and filamentous fungi may also be used as fermenting organisms. Some bacteria have higher fermentation temperature optimum than, e.g., Saccharomyces cerevisae. Therefore, fermentations may in such cases be carried out at temperatures as high as up to 75°C, e.g., at temperature between 40-700C, such as 50- 600C. The skilled person in the art can easily determine suitable fermentation conditions.
However, bacteria with a significantly lower temperature optimum down to around room temperature (around 20°C) are also known. Examples of suitable fermenting organisms can be found in the "Fermenting Organisms" section above.
For, e.g., ethanol production using yeast, such as Saccharomyces cerevisae, the fermentation may in one embodiment go on for 24 to 96 hours, in particular for 35 to 60 hours.
In an embodiment the fermentation is carried out at a temperature between 20 to 400C, preferably 26 to 34°C, in particular around 32°C. In an embodiment the pH is from pH 3 to 6, preferably around pH 4 to 5. Especially contemplated is simultaneous hydrolysis/saccharification and fermentation (SSF) where there is no separate holding stage for the hydrolysis/saccharification, meaning that the hydrolysing enzyme(s), the fermenting organism(s) and agonist compound(s) may be added together. However, it should be understood that the agonist compound(s) may also be added separately. When fermentation is performed simultaneous with hydrolysis/saccharification (SSF) the temperature is preferably between 20 to 400C, preferably 26 to 34°C, in particular around 32°C when the fermentation organism is a strain of Saccharomyces cerevisiae and the desired fermentation product is ethanol.
Other fermentation products may be fermented at temperatures known to the skilled person in the art to be suitable for the fermenting organism in question.
The process of the invention may be performed as a batch or as a continuous process. The fermentation process of the invention may be conducted in an ultrafiltration system where the retentate is held under recirculation in the presence of solids, water, and the fermenting organism, and where the permeate is the desired fermentation product containing liquid. Equally contemplated if the process is conducted in a continuous membrane reactor with ultrafiltration membranes and where the retentate is held under recirculation in presence of solids, water, the fermenting organism and where the permeate is the fermentation product containing liquid.
After fermentation the fermenting organism may be separated from the fermented slurry and recycled.
Fermentations are typically carried out at a pH in the range between 3 and 7, preferably from pH 3.5 to 6, such as around pH 5. Fermentations are typically ongoing for 24-96 hours.
Fermentation of Lignocellulose-derived Sugars
As mentioned above different kinds of fermenting organisms may be used for fermenting sugars derived from lignocellulose-containing material. Fermentations are typically carried out by yeast, bacteria or filamentous fungi, including the ones mentioned in the "Fermenting Organisms" section above. If the aim is C6 fermentable sugars the conditions are usually similar to starch fermentations as described above. However, if the aim is to ferment C5 sugars (e.g., xylose) or a combination of C6 and C5 fermentable sugars the fermenting organism(s) and/or fermentation conditions may differ.
Bacteria fermentations may be carried out at higher temperatures, such as up to 75°C, e.g., between 40-700C, such as between 50-600C, than conventional yeast fermentations, which are typically carried out at temperatures from 20-400C. However, bacteria fermentations at temperature as low as 20°C are also known. Fermentations are typically carried out at a pH in the range between 3 and 7, preferably from pH 3.5 to 6, such as around pH 5. Fermentations are typically ongoing for 24-96 hours.
Production of Fermentation Products from Starch-Containing Material Processes for producing fermentation products from Gelatinized Starch-Containing material In this aspect the present invention relates to a process for producing a fermentation product, especially ethanol, from starch-containing material, which process includes a liquefaction step and sequentially or simultaneously performed saccharification and fermentation steps. The invention relates to a process for producing a fermentation product from starch- containing material comprising the steps of:
(a) liquefying said starch-containing material;
(b) saccharifying the liquefied material obtained in step (a);
(c) fermenting with a fermenting organism, wherein fermentation is carried out in the presence of one or more TRP channel agonist compounds.
In one embodiment, an alpha-amylase is used in the liquefying step (a). In one embodiment, a glucoamylase is used in the saccharifying step (b). In a preferred embodiment the agonist compounds are added before and/or during the fermentation step. In an embodiment the compounds are added to the fermentation medium.
The fermentation product, such as ethanol, may optionally be recovered after fermentation, e.g., by distillation. Suitable starch-containing starting materials are listed in the section "Starch-containing materials" section below. Contemplated enzymes are listed in the "Enzymes" section below. The liquefaction is preferably carried out in the presence of an alpha-amylase, preferably a bacterial alpha-amylase or acid fungal alpha-amylase. The fermenting organism is preferably yeast, preferably a strain of Saccharomyces. Suitable fermenting organisms are listed in the "Fermenting Organisms" section above. In a preferred embodiment step (b) and (c) are carried out sequentially or simultaneously (i.e., as SSF process).
In a particular embodiment, the process of the invention further comprises, prior to the step (a), the steps of: x) reducing the particle size of the starch-containing material, preferably by milling; y) forming a slurry comprising the starch-containing material and water. The aqueous slurry may contain from 10-55 wt. % dry solids, preferably 25-45 wt. % dry solids, more preferably 30-40 wt. % dry solids of starch-containing material. The slurry is heated to above the gelatinization temperature and alpha-amylase, preferably bacterial and/or acid fungal alpha-amylase may be added to initiate liquefaction (thinning). The slurry may in an embodiment be jet-cooked to further gelatinize the slurry before being subjected to an alpha-amylase in step (a) of the invention.
More specifically liquefaction may be carried out as a three-step hot slurry process. The slurry is heated to between 60-950C, preferably 80-850C, and alpha-amylase is added to initiate liquefaction (thinning). Then the slurry may be jet-cooked at a temperature between 95-140°C, preferably 105-1250C, for 1-15 minutes, preferably for 3-10 minutes, especially around 5 minutes. The slurry is cooled to 60-950C and more alpha-amylase is added to finalize hydrolysis (secondary liquefaction). The liquefaction process is usually carried out at pH 4.5-6.5, in particular at a pH between 5 and 6. Milled and liquefied whole grains are known as mash. The saccharification in step (b) may be carried out using conditions well known in the art. For instance, a full saccharification process may last up to from about 24 to about 72 hours, however, it is common only to do a pre-saccharification of typically 40-90 minutes at a temperature between 30-65°C, typically about 60°C, followed by complete saccharification during fermentation in a simultaneous saccharification and fermentation process (SSF process). Saccharification is typically carried out at temperatures from 30-65°C, typically around 600C, and at a pH between 4 and 5, normally at about pH 4.5.
The most widely used process in fermentation product production, especially ethanol production, is simultaneous saccharification and fermentation (SSF) process, in which there is no holding stage for the saccharification. This means that the fermenting organism(s), such as yeast, and enzyme(s) may be added together. SSF may typically be carried out at a temperature between 25°C and 40°C, such as between 29°C and 35°C, such as between 300C and 34°C, such as around 32°C, when the fermentation organism is yeast, such as a strain of Saccharomyces cerevisiae, and the desired fermentation product is ethanol.
Other fermentation products may be fermented at conditions and temperatures, well known to the skilled person in the art, suitable for the fermenting organism in question. According to the invention the temperature may be adjusted up or down during fermentation. Processes for Producing Fermentation Products from Un-gelatinized Starch-containing Material
In this aspect the invention relates to processes for producing a fermentation product from starch-containing material without gelatinization of the starch-containing material (i.e., uncooked starch-containing material). According to the invention the desired fermentation product, such as ethanol, can be produced without liquefying the aqueous slurry containing the starch-containing material. In one embodiment a process of the invention includes saccharifying (milled) starch-containing material, e.g., granular starch, below the gelatinization temperature, preferably in the presence of a carbohydrate-source generating enzyme to produce sugars that can be fermented into the desired fermentation product by a suitable fermenting organism.
In this embodiment the desired fermentation product, preferably ethanol, is produced from un-gelatinized (i.e., uncooked) milled corn.
Accordingly, in this aspect the invention relates to processes of producing a fermentation product from starch-containing material, comprising the steps of:
(a) saccharifying starch-containing material at a temperature below the initial gelatinization temperature of said starch-containing material;
(b) fermenting with a fermenting organism; wherein the fermentation is carried out in the presence of one or more TRP channel agonist compounds.
In a preferred embodiment steps (a) and (b) are carried out simultaneously (i.e., one step fermentation) or sequentially. The fermentation step (b) may be carried in accordance with the fermentation process of the invention.
The fermentation product, such as especially ethanol, may optionally be recovered after fermentation, e.g., by distillation. Suitable starch-containing starting materials are listed in the section "Starch-containing Materials" section below. Contemplated enzymes are listed in the "Enzymes" section below. Alpha-amylases used are preferably acidic, preferably acid fungal alpha-amylases. The fermenting organism is preferably yeast, preferably a strain of Saccharomyces. Suitable fermenting organisms are listed in the "Fermenting Organisms" section above.
The term "below the initial gelatinization temperature" means below the lowest temperature where gelatinization of the starch commences. Starch heated in water typically begins to gelatinize between 500C and 75°C; the exact temperature of gelatinization depends on the specific starch, and can readily be determined by the skilled artisan. Thus, the initial gelatinization temperature may vary according to the plant species, to the particular variety of the plant species as well as with the growth conditions. In the context of this invention the initial gelatinization temperature of a given starch-containing material is the temperature at which birefringence is lost in 5% of the starch granules using the method described by Gorinstein and Lii, 1992, Starch/Starke 44 (12): 461-466.
Before step (a) a slurry of starch-containing material, such as granular starch, having 10-55 wt. % dry solids, preferably 25-45 wt. % dry solids, more preferably 30-40 wt. % dry solids of starch-containing material may be prepared. The slurry may include water and/or process waters, such as stillage (backset), scrubber water, evaporator condensate or distillate, side stripper water from distillation, or other fermentation product plant process water. Because the process of the invention is carried out below the gelatinization temperature and thus no significant viscosity increase takes place, high levels of stillage may be used if desired. In an embodiment the aqueous slurry contains from about 1 to about 70 vol. % stillage, preferably 15-60% vol. % stillage, especially from about 30 to 50 vol. % stillage.
The starch-containing material may be prepared by reducing the particle size, preferably by dry or wet milling, to 0.05 to 3.0 mm, preferably 0.1-0.5 mm. After being subjected to a process of the invention at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91 %, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, or preferably at least 99% of the dry solids of the starch-containing material is converted into a soluble starch hydrolyzate. The process of this aspect of the invention is conducted at a temperature below the initial gelatinization temperature. When step (a) is carried out separately from fermentation step (b) the temperature typically lies in the range between 30-750C, preferably in the range from 45-600C. The following separate fermentation step (b) is then carried out at a temperature suitable for the fermenting organism, which typically is in the range between 25-4O0C when the fermenting organism is yeast.
In a preferred embodiment step (a) and step (b) are carried out as a simultaneous saccharification and fermentation process. In such embodiment the process is typically carried at a temperature between 25°C and 400C, such as between 29°C and 35°C, such as between 300C and 34°C, such as around 32°C, when the fermenting organism is yeast. One skilled in the art can easily determine which process conditions are suitable.
In an embodiment simultaneous saccharification and fermentation is carried out so that the sugar level, such as glucose level, is kept at a low level such as below 6 wt. %, preferably below about 3 wt. %, preferably below about 2 wt. %, more preferred below about 1 wt. %., even more preferred below about 0.5 wt. %, or even more preferred 0.25% wt. %, such as below about 0.1 wt. %. Such low levels of sugar can be accomplished by simply employing adjusted quantities of enzyme and fermenting organism. A skilled person in the art can easily determine which quantities of enzyme and fermenting organism to use. The employed quantities of enzyme and fermenting organism may also be selected to maintain low concentrations of maltose in the fermentation broth. For instance, the maltose level may be kept below about 0.5 wt. % or below about 0.2 wt. %. The process of the invention may be carried out at a pH in the range between 3 and
7, preferably from pH 3.5 to 6, or more preferably from pH 4 to 5.
Starch-containing Materials
Any suitable starch-containing starting material, including granular starch, may be used according to the present invention. The starting material is generally selected based on the desired fermentation product. Examples of starch-containing starting materials, suitable for use in a process of present invention, include tubers, roots, stems, whole grains, corns, cobs, wheat, barley, rye, milo, sago, cassava, tapioca, sorghum, rice peas, beans, or sweet potatoes, or mixtures thereof, or cereals, sugar-containing raw materials, such as molasses, fruit materials, sugar cane or sugar beet, potatoes, and cellulose-containing materials, such as wood or plant residues, or mixtures thereof. Contemplated are both waxy and non-waxy types of corn and barley.
The term "granular starch" means raw uncooked starch, i.e., starch in its natural form found in cereal, tubers or grains. Starch is formed within plant cells as tiny granules insoluble in water. When put in cold water, the starch granules may absorb a small amount of the liquid and swell. At temperatures up to 500C to 75°C the swelling may be reversible. However, with higher temperatures an irreversible swelling called "gelatinization" begins. Granular starch to be processed may in an embodiment be a highly refined starch, preferably at least 90%, at least 95%, at least 97% or at least 99.5% pure, or it may be a more crude starch containing material comprising milled whole grain including non-starch fractions such as germ residues and fibers. The raw material, such as whole grain, is milled in order to open up the structure and allowing for further processing. Two milling processes are preferred according to the invention: wet and dry milling. In dry milling whole kernels are milled and used. Wet milling gives a good separation of germ and meal (starch granules and protein) and is often applied at locations where the starch hydrolyzate is used in production of syrups. Both dry and wet milling is well known in the art of starch processing and is equally contemplated for the process of the invention.
The starch-containing material may be reduced in particle size, preferably by dry or wet milling, in order to expose more surface area. In an embodiment the particle size is between 0.05 to 3.0 mm, preferably 0.1-0.5 mm, or so that at least 30%, preferably at least 50%, more preferably at least 70%, even more preferably at least 90% of the starch- containing material fit through a sieve with a 0.05 to 3.0 mm screen, preferably 0.1-0.5 mm screen.
Production of Fermentation Products from Liqnocellulose-Containinq Material (Biomass)
In this aspect the invention relates to processes of producing desired fermentation products from lignocellulose-containing material. Conversion of lignocellulose-containing material into fermentation products, such as ethanol, has the advantages of the ready availability of large amounts of feedstock, including wood, agricultural residues, herbaceous crops, municipal solid wastes etc. Lignocellulose-containing materials primarily consist of cellulose, hemicellulose, and lignin and are often referred to as "biomass".
The structure of lignocellulose is not directly accessible to enzymatic hydrolysis. Therefore, the lignocellulose-containing material has to be pre-treated, e.g., by acid hydrolysis under adequate conditions of pressure and temperature, in order to break the lignin seal and disrupt the crystalline structure of cellulose. This causes solubilization of the hemicellulose and cellulose fractions. The cellulose and hemicelluloses can then be hydrolyzed enzymatically, e.g., by cellulolytic enzymes, to convert the carbohydrate polymers into fermentable sugars which may be fermented into a desired fermentation product, such as ethanol. Optionally the fermentation product may be recovered, e.g., by distillation. In this aspect the invention relates to a process of producing a fermentation product from lignocellulose-containing material, comprising the steps of:
(a) pre-treating lignocellulose-containing material;
(b) hydrolyzing the material from step (a);
(c) fermenting using a fermenting organism; wherein fermentation is carried out in the presence of one or more TRP channel agonist compounds.
The agonist compounds may be added before and/or during fermentation. In a preferred embodiment the agonist compounds are added to the fermentation medium. The fermentation step (c) may be carried in accordance with the fermentation process of the invention. In preferred embodiments the steps are carried out as SSF, HHF or SHF process steps which will be described further below.
Pre-treatment
The lignocellulose-containing material may be pre-treated before being hydrolyzed and/or fermented. In a preferred embodiment the pre-treated material is hydrolyzed, preferably enzymatically, before and/or during fermentation. The goal of pre-treatment is to separate and/or release cellulose, hemicellulose and/or lignin and this way improve the rate of enzymatic hydrolysis.
According to the invention pre-treatment step (a) may be a conventional pre- treatment step known in the art. Pre-treatment may take place in aqueous slurry. The lignocellulose-containing material may during pre-treatment be present in an amount between 10-80 wt. %, preferably between 20-50 wt.-%.
Chemical, Mechanical and/or Biological Pre-treatment
The lignocellulose-containing material may according to the invention be chemically, mechanically and/or biologically pre-treated before hydrolysis and/or fermentation. Mechanical treatment (often referred to as physical treatment) may be used alone or in combination with subsequent or simultaneous hydrolysis, especially enzymatic hydrolysis, to promote the separation and/or release of cellulose, hemicellulose and/or lignin.
Preferably, the chemical, mechanical and/or biological pre-treatment is carried out prior to the hydrolysis and/or fermentation. Alternatively, the chemical, mechanical and/or biological pre-treatment is carried out simultaneously with hydrolysis, such as simultaneously with addition of one or more cellulolytic enzymes, or other enzyme activities mentioned below, to release fermentable sugars, such as glucose and/or maltose.
In an embodiment of the invention the pre-treated lignocellulose-containing material is washed and/or detoxified before hydrolysis step (b). This may improve the fermentability of, e.g., dilute-acid hydrolyzed lignocellulose-containing material, such as corn stover and corn cobs. Detoxification may be carried out in any suitable way, e.g., by steam stripping, evaporation, ion exchange, resin or charcoal treatment of the liquid fraction or by washing the pre-treated material. In a preferred embodiment gallic acid is added to either washed and/or unwashed lignocellulose-containing material before, during and/or after pre-treatment in step (a). In other words, gallic acid may be used as a detoxification agent and may be added before, during and/or after pre-treatment in step (a).
Chemical Pre-treatment According to the present invention "chemical pre-treatment" refers to any chemical treatment which promotes the separation and/or release of cellulose, hemicellulose and/or lignin. Examples of suitable chemical pre-treatment steps include treatment with; for example, dilute acid, lime, alkaline, organic solvent, ammonia, sulfur dioxide, carbon dioxide. Further, wet oxidation and pH-controlled hydrothermolysis are also contemplated chemical pre-treatments. Preferably, the chemical pre-treatment is acid treatment, more preferably, a continuous dilute and/or mild acid treatment, such as, treatment with sulfuric acid, or another organic acid, such as acetic acid, citric acid, tartaric acid, succinic acid, or mixtures thereof. Other acids may also be used. Mild acid treatment means in the context of the present invention that the treatment pH lies in the range from 1-5, preferably 1-3. In a specific embodiment the acid concentration is in the range from 0.1 to 2.0 wt % acid, preferably sulphuric acid. The acid may be mixed or contacted with the material to be fermented according to the invention and the mixture may be held at a temperature in the range of 160-2200C, such as 165-195°C, for periods ranging from minutes to seconds, e.g., 1-60 minutes, such as 2-30 minutes or 3-12 minutes. Addition of strong acids, such as sulphuric acid, may be applied to remove hemicellulose. This enhances the digestibility of cellulose. Cellulose solvent treatment has been shown to convert about 90% of cellulose to glucose. It has also been shown that enzymatic hydrolysis could be greatly enhanced when the lignocellulosic structure is disrupted. Alkaline H2O2, ozone, organosolv (uses Lewis acids, FeCI3, (AI)2SO4 in aqueous alcohols), glycerol, dioxane, phenol, or ethylene glycol are among solvents known to disrupt cellulose structure and promote hydrolysis (Mosier et al., 2005, Bioresource Technology 96: 673-686).
Alkaline chemical pre-treatment with base, e.g., NaOH and/or Na2CO3 and/or the like, is also contemplated according to the invention. Pre-treatment methods using ammonia are described in, e.g., WO 2006/110891 , WO 2006/11899, WO 2006/11900, and WO 2006/110901 , which are hereby incorporated by reference. Wet oxidation techniques involve use of oxidizing agents, such as: sulphite based oxidizing agents and the like. Examples of solvent pre-treatments include treatment with DMSO (dimethyl sulfoxide) and the like. Chemical pre-treatment is generally carried out for 1 to 60 minutes, such as from 5 to 30 minutes, but may be carried out for shorter or longer periods of time dependent on the material to be pre-treated. Other examples of suitable pre-treatment methods are described by Schell et al., 2003,
Appl. Biochem and Biotechn. 105-108: 69-85, and Mosier et al., 2005, Bioresource Technology 96: 673-686, and U.S. application publication no. 2002/0164730, which references are hereby all incorporated by reference. In a preferred embodiment the cellulosic material, preferably lignocellulosic material, is treated chemically and/or mechanically pre-treated.
Mechanical Pre-treatment
As used in context of the present invention, the term "mechanical pre-treatment" refers to any mechanical or physical treatment which promotes the separation and/or release of cellulose, hemicellulose and/or lignin from lignocellulose-containing material. For example, mechanical pre-treatment includes various types of milling, irradiation, steaming/steam explosion, and hydrothermolysis. Mechanical pre-treatment includes comminution (mechanical reduction of the particle size). Comminution includes dry milling, wet milling and vibratory ball milling. Mechanical pre- treatment may involve high pressure and/or high temperature (steam explosion). In an embodiment of the invention high pressure means pressure in the range from 300 to 600 psi, preferably 400 to 500 psi, such as around 450 psi. In an embodiment of the invention high temperature means temperatures in the range from about 100 to 3000C, preferably from about 140 to 235°C. In a preferred embodiment mechanical pre-treatment is a batch-process, steam gun hydrolyzer system which uses high pressure and high temperature as defined above. A Sunds Hydrolyzer (available from Sunds Defibrator AB (Sweden) may be used for this.
Combined Chemical and Mechanical Pre-treatment
In a preferred embodiment both chemical and mechanical pre-treatment is carried out involving, for example, both dilute or mild acid treatment and high temperature and pressure treatment. The chemical and mechanical pre-treatment may be carried out sequentially or simultaneously, as desired.
Accordingly, in a preferred embodiment, the lignocellulose-containing material is subjected to both chemical and mechanical pre-treatment to promote the separation and/or release of cellulose, hemicellulose and/or lignin.
In a preferred embodiment the pre-treatment is carried out as a dilute and/or mild acid steam explosion step. In another preferred embodiment pre-treatment is carried out as an ammonia fiber explosion step (or AFEX pre-treatment step).
Biological Pre-treatment
As used in the present invention the term "biological pre-treatment" refers to any biological pre-treatment which promotes the separation and/or release of cellulose, hemicellulose, and/or lignin from the lignocellulose-containing material. Biological pre- treatment techniques can involve applying lignin-solubilizing microorganisms (see, for example, Hsu, 1996, Pretreatment of biomass, in Handbook on Bioethanol: Production and Utilization, Wyman, C. E., ed., Taylor & Francis, Washington, DC, 179-212; Ghosh and Singh, 1993, Physicochemical and biological treatments for enzymatic/microbial conversion of lignocellulosic biomass, Adv. Appl. Microbiol. 39: 295-333; McMillan, 1994, Pretreating lignocellulosic biomass: a review, in Enzymatic Conversion of Biomass for Fuels Production, Himmel, Baker, and Overend, eds., ACS Symposium Series 566, American Chemical Society, Washington, DC, chapter 15; Gong, Cao, Du, and Tsao, 1999, Ethanol production from renewable resources, in Advances in Biochemical Engineering/Biotechnology, Scheper, ed., Springer-Verlag Berlin Heidelberg, Germany, 65: 207-241 ; Olsson and Hahn- Hagerdal, 1996, Fermentation of lignocellulosic hydrolysates for ethanol production, Enz. Microb. Tech. 18: 312-331 ; and Vallander and Eriksson, 1990, Production of ethanol from lignocellulosic materials: State of the art, Adv. Biochem. Eng./Biotechnol. 42: 63-95).
Hydrolysis
Before and/or during the fermentation the pre-treated lignocellulose-containing material may be hydrolyzed in order to break the lignin seal and disrupt the crystalline structure of cellulose. In a preferred embodiment hydrolysis is carried out enzymatically. According to the invention the pre-treated lignocellulose-containing material, to be fermented may be hydrolyzed by one or more hydrolases (class EC 3 according to the Enzyme Nomenclature), preferably one or more carbohydrases selected from the group consisting of cellulase, hemicellulase, or amylase, such as alpha-amylase, maltogenic amylase or beta-amylase. A protease may also be present.
The enzyme(s) used for hydrolysis is(are) capable of directly or indirectly converting carbohydrate polymers into fermentable sugars, such as glucose and/or maltose, which can be fermented into a desired fermentation product, such as ethanol.
In a preferred embodiment the carbohydrase has cellulolytic enzyme activity. Suitable carbohydrases are described in the "Enzymes" section below.
Hemicellulose polymers can be broken down by hemicellulases and/or acid hydrolysis to release its five and six carbon sugar components. The six carbon sugars (hexoses), such as glucose, galactose and mannose, can readily be fermented to, e.g., ethanol, acetone, butanol, glycerol, citric acid, fumaric acid etc. by suitable fermenting organisms including yeast. Preferred for ethanol fermentation is yeast of the species Saccharomyces cerevisiae, preferably strains which are resistant towards high levels of ethanol, i.e., up to, e.g., about 10, 12 or 15 vol. % or more ethanol.
In a preferred embodiment the pre-treated lignocellulose-containing material, is hydrolyzed using a hemicellulase, preferably a xylanase, esterase, cellobiase, or combination thereof.
Hydrolysis may also be carried out in the presence of a combination of hemicellulases and/or cellulases, and optionally one or more of the other enzyme activities mentioned above.
The enzymatic treatment may be carried out in a suitable aqueous environment under conditions which can readily be determined by one skilled in the art. In a preferred embodiment hydrolysis is carried out at optimal conditions for the enzyme(s) in question.
Suitable process time, temperature and pH conditions can readily be determined by one skilled in the art present invention. Preferably, hydrolysis is carried out at a temperature between 30 and 700C, preferably between 40 and 600C, especially around 50°C. The process is preferably carried out at a pH in the range from 3-8, preferably pH 4-6, especially around pH 5. Preferably, hydrolysis is carried out for between 8 and 72 hours, preferably between 12 and 48 hours, especially around 24 hours.
Fermentation of Lignocellulose derived Material
Fermentation of lignocellulose-containing material may be carried out in accordance with a fermentation process of the invention as described above. According to the invention hydrolysis in step (b) and fermentation in step (c) may be carried out simultaneously (SSF process) or sequentially (SHF process).
SSF, HHF and SHF
Hydrolysis and fermentation may be carried out as a simultaneous hydrolysis and fermentation step (SSF). In general, this means that combined/simultaneous hydrolysis and fermentation are carried out at conditions (e.g., temperature and/or pH) suitable, preferably optimal, for the fermenting organism(s) in question.
The hydrolysis step and fermentation step may be carried out as hybrid hydrolysis and fermentation (HHF). HHF typically begins with a separate partial hydrolysis step and ends with a simultaneous hydrolysis and fermentation step. The separate partial hydrolysis step is an enzymatic cellulose saccharification step typically carried out at conditions (e.g., at higher temperatures) suitable, preferably optimal, for the hydrolyzing enzyme(s) in question. The subsequent simultaneous hydrolysis and fermentation step is typically carried out at conditions suitable for the fermenting organism(s) (often at lower temperatures than the separate hydrolysis step).
The hydrolysis and fermentation steps may also be carried out as separate hydrolysis and fermentation, where the hydrolysis is taken to completion before initiation of fermentation. This is often referred to as "SHF".
Recovery
Subsequent to fermentation, the fermentation product may optionally be separated from the fermentation medium in any suitable way. For instance, the medium may be distilled to extract the fermentation product, or the fermentation product may be extracted from the fermentation medium by micro or membrane filtration techniques. Alternatively, the fermentation product may be recovered by stripping. Recovery methods are well known in the art.
Fermentation Products The present invention may be used for producing any fermentation product. Preferred fermentation products include alcohols (e.g., ethanol, methanol, butanol); organic acids (e.g., citric acid, acetic acid, itaconic acid, lactic acid, gluconic acid); ketones (e.g., acetone); amino acids (e.g., glutamic acid); gases (e.g., H2 and CO2); antibiotics (e.g., penicillin and tetracycline); enzymes; vitamins (e.g., riboflavin, B12, beta-carotene); and hormones.
Other products include consumable alcohol industry products, e.g., beer and wine; dairy industry products, e.g., fermented dairy products; leather industry products and tobacco industry products. In a preferred embodiment, the fermentation product is an alcohol, especially ethanol. The fermentation product, such as ethanol, obtained according to the invention, may preferably be used as fuel alcohol/ethanol. However, in the case of ethanol, it may also be used as potable ethanol.
Lignocellulose-containing Material (Biomass)
Any suitable lignocellulose-containing material is contemplated in context of the present invention. Lignocellulose-containing material may be any material containing lignocellulose.
In a preferred embodiment the lignocellulose-containing material contains at least 50 wt. %, preferably at least 70 wt-%, more preferably at least 90 wt-% lignocellulose. It is to be understood that the lignocellulose-containing material may also comprise other constituents such as cellulosic material, such as cellulose, hemicellulose, and may also comprise constituents such as sugars, such as fermentable sugars and/or un-fermentable sugars.
Lignocellulose-containing material is generally found, for example, in the stems, leaves, hulls, husks, and cobs of plants or leaves, branches, and wood of trees. Lignocellulosic material can also be, but is not limited to, herbaceous material, agricultural residues, forestry residues, municipal solid wastes, waste paper, and pulp and paper mill residues. It is understood herein that lignocellulose-containing material may be in the form of plant cell wall material containing lignin, cellulose, and hemi-cellulose in a mixed matrix.
In an embodiment the lignocellulose-containing material is corn stover, corn cobs, corn fiber, rice straw, pine wood, wood chips, poplar, wheat straw, switchgrass, bagasse, paper and pulp processing waste. Other more specific examples include corn stover, corn cobs, corn fiber, hardwood, such as poplar and birch, softwood, cereal straw, such as wheat straw, switch grass, municipal solid waste (MSW), industrial organic waste, office paper, or mixtures thereof.
In a preferred aspect, the material is corn stover or corn cobs. In another preferred aspect, the material is corn fiber. Enzymes
Even if not specifically mentioned in context of a process of the invention, it is to be understood that the enzyme(s) is(are) used in an effective amount.
Alpha-Amylase
According to the invention an alpha-amylase may be used any alpha-amylase. In a preferred embodiment the alpha-amylase is an acid alpha-amylase, e.g., fungal acid alpha- amylase or bacterial acid alpha-amylase. The term "acid alpha-amylase" means an alpha- amylase (E. C. 3.2.1.1 ) which added in an effective amount has activity optimum at a pH in the range of 3 to 7, preferably from 3.5 to 6, or more preferably from 4-5.
Bacterial Alpha-Amylase
According to the invention the bacterial alpha-amylase is preferably derived from the genus Bacillus. In a preferred embodiment the Bacillus alpha-amylase is derived from a strain of B. licheniformis, B. amyloliquefaciens, B. subtilis or B. stearothermophilus, but may also be derived from other Bacillus sp. Specific examples of contemplated alpha-amylases include the Bacillus licheniformis alpha-amylase shown in SEQ ID NO: 4 in WO 99/19467, the Bacillus amyloliquefaciens alpha-amylase SEQ ID NO: 5 in WO 99/19467 and the Bacillus stearothermophilus alpha-amylase shown in SEQ ID NO: 3 in WO 99/19467 (all sequences hereby incorporated by reference). In an embodiment of the invention the alpha-amylase may be an enzyme having a degree of identity of at least 60%, preferably at least 70%, more preferred at least 80%, even more preferred at least 90%, such as at least 95%, at least 96%, at least 97%, at least 98% or at least 99% to any of the sequences shown in SEQ ID NO: 1 , 2 or 3, respectively, in WO 99/19467.
The Bacillus alpha-amylase may also be a variant and/or hybrid, especially one described in any of WO 96/23873, WO 96/23874, WO 97/41213, WO 99/19467, WO 00/60059, and WO 02/10355 (all documents hereby incorporated by reference). Specifically contemplated alpha-amylase variants are disclosed in U.S. Patent Nos. 6,093,562, 6,297,038 or U.S. Patent No. 6,187,576 (hereby incorporated by reference) and include Bacillus stearothermophilus alpha-amylase (BSG alpha-amylase) variants having a deletion of one or two amino acid in positions R179 to G182, preferably a double deletion disclosed in WO 1996/023873 - see e.g., page 20, lines 1-10 (hereby incorporated by reference), preferably corresponding to delta(181-182) compared to the wild-type BSG alpha-amylase amino acid sequence set forth in SEQ ID NO: 3 disclosed in WO 99/19467 or deletion of amino acids R179 and G180 using SEQ ID NO: 3 in WO 99/19467 for numbering (which reference is hereby incorporated by reference). Even more preferred are Bacillus alpha- amylases, especially Bacillus stearothermophilus alpha-amylase, which have a double deletion corresponding to delta(181-182) and further comprise a N193F substitution (also denoted 1181* + G182* + N193F) compared to the wild-type BSG alpha-amylase amino acid sequence set forth in SEQ ID NO: 3 disclosed in WO 99/19467.
Bacterial Hybrid Alpha-Amylase
A hybrid alpha-amylase specifically contemplated comprises 445 C-terminal amino acid residues of the Bacillus licheniformis alpha-amylase (shown in SEQ ID NO: 4 of WO 99/19467) and the 37 N-terminal amino acid residues of the alpha-amylase derived from
Bacillus amyloliquefaciens (shown in SEQ ID NO: 5 of WO 99/19467), with one or more, especially all, of the following substitution:
G48A+T49I+G107A+H156Y+A181T+N190F+I201 F+A209V+Q264S (using the
Bacillus licheniformis numbering in SEQ ID NO: 4 of WO 99/19467). Also preferred are variants having one or more of the following mutations (or corresponding mutations in other
Bacillus alpha-amylase backbones): H154Y, A181T, N190F, A209V and Q264S and/or deletion of two residues between positions 176 and 179, preferably deletion of E178 and
G179 (using SEQ ID NO: 5 numbering of WO 99/19467).
In an embodiment the bacterial alpha-amylase is dosed in an amount of 0.0005-5 KNU per g DS (dry solids), preferably 0.001-1 KNU per g DS, such as around 0.050 KNU per g DS.
Fungal Alpha-Amylase
Fungal alpha-amylases include alpha-amylases derived from a strain of the genus Aspergillus, such as, Aspergillus oryzae, Aspergillus niger and Aspergillis kawachii alpha- amylases.
A preferred acidic fungal alpha-amylase is a Fungamyl-like alpha-amylase which is derived from a strain of Aspergillus oryzae. According to the present invention, the term "Fungamyl-like alpha-amylase" indicates an alpha-amylase which exhibits a high identity, i.e., more than 70%, more than 75%, more than 80%, more than 85% more than 90%, more than 95%, more than 96%, more than 97%, more than 98%, more than 99% or even 100% identity to the mature part of the amino acid sequence shown in SEQ ID NO: 10 in WO 96/23874.
Another preferred acidic alpha-amylase is derived from a strain Aspergillus niger. In a preferred embodiment the acid fungal alpha-amylase is the one from A. niger disclosed as
"AMYA_ASPNG" in the Swiss-prot/TeEMBL database under the primary accession no. P56271 and described in WO 89/01969 (Example 3). A commercially available acid fungal alpha-amylase derived from Aspergillus niger is SP288 (available from Novozymes A/S, Denmark).
Other contemplated wild-type alpha-amylases include those derived from a strain of the genera Rhizomucor and Meripilus, preferably a strain of Rhizomucor pusillus (WO 2004/055178 incorporated by reference) or Meripilus giganteus.
In a preferred embodiment the alpha-amylase is derived from Aspergillus kawachii and disclosed by Kaneko et al., 1996, J. Ferment. Bioeng. 81 : 292-298, "Molecular-cloning and determination of the nucleotide-sequence of a gene encoding an acid-stable alpha- amylase from Aspergillus kawachir; and further as EMBL:#AB008370.
The fungal alpha-amylase may also be a wild-type enzyme comprising a starch- binding domain (SBD) and an alpha-amylase catalytic domain (i.e., non-hybrid), or a variant thereof. In an embodiment the wild-type alpha-amylase is derived from a strain of Aspergillus kawachii.
Fungal Hybrid Alpha-Amylase
In a preferred embodiment the fungal acid alpha-amylase is a hybrid alpha-amylase.
Preferred examples of fungal hybrid alpha-amylases include the ones disclosed in WO
2005/003311 or U.S. application publication no. 2005/0054071 (Novozymes) or U.S. application no. 60/638,614 (Novozymes) which is hereby incorporated by reference. A hybrid alpha-amylase may comprise an alpha-amylase catalytic domain (CD) and a carbohydrate-binding domain/module (CBM), such as a starch binding domain, and optional a linker.
Specific examples of contemplated hybrid alpha-amylases include those disclosed in Table 1 to 5 of the examples in U.S. application no. 60/638,614, including Fungamyl variant with catalytic domain JA118 and Athelia rolfsii SBD (SEQ ID NO:100 in US 60/638,614), Rhizomucor pusillus alpha-amylase with Athelia rolfsii AMG linker and SBD (SEQ ID NO:101 in US 60/638,614), Rhizomucor pusillus alpha-amylase with Aspergillus niger glucoamylase linker and SBD (which is disclosed in Table 5 as a combination of amino acid sequences SEQ ID NO: 20, SEQ ID NO: 72 and SEQ ID NO: 96 in U.S. application no. 1 1/316,535) or as V039 in Table 5 in WO 2006/069290, and Meripilus giganteus alpha-amylase with Athelia rolfsii glucoamylase linker and SBD (SEQ ID NO: 102 in U.S. application no. 60/638,614). Other specifically contemplated hybrid alpha-amylases are any of the ones listed in Tables 3, 4, 5, and 6 in Example 4 in U.S. application no. 11/316,535 and WO 2006/069290 (hereby incorporated by reference). Other specific examples of contemplated hybrid alpha-amylases include those disclosed in U.S. application publication no. 2005/0054071 , including those disclosed in Table 3 on page 15, such as Aspergillus niger alpha-amylase with Aspergillus kawachii linker and starch binding domain. Contemplated are also alpha-amylases which exhibit a high identity to any of above mention alpha-amylases, i.e., more than 70%, more than 75%, more than 80%, more than 85% more than 90%, more than 95%, more than 96%, more than 97%, more than 98%, more than 99% or even 100% identity to the mature enzyme sequences.
An acid alpha-amylases may according to the invention be added in an amount of 0.1 to 10 AFAU/g DS, preferably 0.10 to 5 AFAU/g DS, especially 0.3 to 2 AFAU/g DS or 0.001 to 1 FAU-F/g DS, preferably 0.01 to 1 FAU-F/g DS.
Commercial Alpha-Amylase Products
Preferred commercial compositions comprising alpha-amylase include MYCOLASE from DSM (Gist Brocades), BAN™, TERMAMYL™ SC, FUNGAMYL™, LIQUOZYME™ X and SAN™ SUPER, SAN™ EXTRA L (Novozymes A/S) and CLARASE™ L-40,000, DEX- LO™, SPEZYME™ FRED, SPEZYME™ AA, SPEZYME™ DELTA AA, SPEZYME XTRA™ (Genencor Int., USA), FUELZYME™ (from Verenium Corp, USA) and the acid fungal alpha- amylase sold under the trade name SP288 (available from Novozymes A/S, Denmark).
Carbohydrate-Source Generating Enzyme
The term "carbohydrate-source generating enzyme" includes glucoamylase (being glucose generators), beta-amylase and maltogenic amylase (being maltose generators). A carbohydrate-source generating enzyme is capable of producing a carbohydrate that can be used as an energy-source by the fermenting organism(s) in question, for instance, when used in a process of the invention for producing a fermentation product, such as ethanol. The generated carbohydrate may be converted directly or indirectly to the desired fermentation product, preferably ethanol. According to the invention a mixture of carbohydrate-source generating enzymes may be used. Especially contemplated mixtures are mixtures of at least a glucoamylase and an alpha-amylase, especially an acid amylase, even more preferred an acid fungal alpha-amylase. The ratio between acid fungal alpha- amylase activity (AFAU) per glucoamylase activity (AGU) (AFAU per AGU) may in an embodiment of the invention be at least 0.1 , or at least 0.16, such as in the range from 0.12 to 0.50 or more. The ratio between acid fungal alpha-amylase activity (FAU-F) and glucoamylase activity (AGU) (i.e., FAU-F per AGU) may in an embodiment of the invention be between 0.1 and 100, in particular between 2 and 50, such as in the range from 10-40.
Glucoamylase
A glucoamylase used according to the invention may be derived from any suitable source, e.g., derived from a microorganism or a plant. Preferred glucoamylases are of fungal or bacterial origin, selected from the group consisting of Aspergillus glucoamylases, in particular A. niger GΪ or G2 glucoamylase (Boel et al., 1984, EMBO J. 3 (5): 1097-1 102), or variants thereof, such as those disclosed in WO 92/00381 , WO 00/04136 and WO 01/04273 (from Novozymes, Denmark); the A. awamori glucoamylase disclosed in WO 84/02921 , A. oryzae glucoamylase (Agric. Biol. Chem., 1991 , 55 (4): 941-949), or variants or fragments thereof. Other Aspergillus glucoamylase variants include variants with enhanced thermal stability: G137A and G139A (Chen et al., 1996, Prot. Eng. 9: 499-505); D257E and D293E/Q (Chen et al., 1995, Prot. Eng. 8: 575-582); N182 (Chen et al., 1994, Biochem. J. 301 : 275-281 ); disulphide bonds, A246C (Fierobe et al., 1996, Biochemistry 35: 8698-8704; and introduction of Pro residues in position A435 and S436 (Li et al., 1997, Protein Eng. 10: 1 199-1204.
Other glucoamylases include Athelia rolfsii (previously denoted Corticium rolfsii) glucoamylase (see U.S. Patent No. 4,727,026 and Nagasaka et al., 1998, "Purification and properties of the raw-starch-degrading glucoamylases from Corticium rolfsii, Appl Microbiol Biotechnol 50:323-330), Talaromyces glucoamylases, in particular derived from Talaromyces emersonii (WO 99/28448), Talaromyces leycettanus (U.S. Patent No. Re. 32,153), Talaromyces duponti, and Talaromyces thermophilus (U.S. Patent No. 4,587,215). Bacterial glucoamylases contemplated include glucoamylases from the genus
Clostridium, in particular C. thermoamylolyticum (EP 135,138), and C. thermohydrosulfuricum (WO 86/01831 ) and Trametes cingulata disclosed in WO 2006/069289 (which is hereby incorporated by reference).
Also hybrid glucoamylases are contemplated according to the invention. Examples of hybrid glucoamylases are disclosed in WO 2005/045018. Specific examples include the hybrid glucoamylases disclosed in Tables 1 and 4 of Example 1 (which hybrids are hereby incorporated by reference.).
Contemplated are also glucoamylases which exhibit a high identity to any of above mention glucoamylases, i.e., more than 70%, more than 75%, more than 80%, more than 85% more than 90%, more than 95%, more than 96%, more than 97%, more than 98%, more than 99% or even 100% identity to the mature enzymes sequences. Commercially available compositions comprising glucoamylase include AMG 200L; AMG 300 L; SAN™ SUPER, SAN™ EXTRA L, SPIRIZYME™ PLUS, SPIRIZYME™ FUEL, SPIRIZYME™ B4U, SPIRIZYME ULTRA™ and AMG™ E (from Novozymes A/S, Denmark); OPTIDEX™ 300, GC480™ and GC147™ (from Genencor Int., USA); AMIGASE™ and AMIGASE™ PLUS (from DSM); G-ZYME™ G900, G-ZYME™ and G990 ZR (from Genencor Int.).
Glucoamylases may in an embodiment be added in an amount of 0.02-20 AGU/g DS, preferably 0.1-10 AGU/g DS, especially between 1-5 AGU/g DS, such as 0.1-2 AGU/g DS, such as 0.5 AGU/g DS or in an amount of 0.0001-20 AGU/g DS, preferably 0.001-10 AGU/g DS, especially between 0.01-5 AGU/g DS, such as 0.1-2 AGU/g DS.
Beta-Am ylase
At least according to the invention the a beta-amylase (E. C 3.2.1.2) is the name traditionally given to exo-acting maltogenic amylases, which catalyze the hydrolysis of 1 ,4- alpha-glucosidic linkages in amylose, amylopectin and related glucose polymers. Maltose units are successively removed from the non-reducing chain ends in a step-wise manner until the molecule is degraded or, in the case of amylopectin, until a branch point is reached.
The maltose released has the beta anomeric configuration, hence the name beta-amylase.
Beta-amylases have been isolated from various plants and microorganisms (W. M. Fogarty and CT. Kelly, 1979, Progress in Industrial Microbiology 15: 1 12-1 15). These beta- amylases are characterized by having optimum temperatures in the range from 400C to 65°C and optimum pH in the range from 4.5 to 7. A commercially available beta-amylase from barley is NOVOZYM™ WBA from Novozymes A/S, Denmark and SPEZYME™ BBA 1500 from Genencor Int., USA.
Maltogenic amylase
The amylase may also be a maltogenic alpha-amylase. A "maltogenic alpha- amylase" (glucan 1 ,4-alpha-maltohydrolase, E. C. 3.2.1.133) is able to hydrolyze amylose and amylopectin to maltose in the alpha-configuration. A maltogenic amylase from Bacillus stearothermophilus strain NCIB 11837 is commercially available from Novozymes A/S. Maltogenic alpha-amylases are described in U.S. Patent Nos. 4,598,048, 4,604,355 and 6,162,628, which are hereby incorporated by reference.
The maltogenic amylase may in a preferred embodiment be added in an amount of 0.05- 5 mg total protein/gram DS or 0.05- 5 MANU/g DS. Proteases
The protease may be any protease, such as of microbial or plant origin. In a preferred embodiment the protease is an acid protease of microbial origin, preferably of fungal or bacterial origin. Suitable proteases include microbial proteases, such as fungal and bacterial proteases. Preferred proteases are acidic proteases, i.e., proteases characterized by the ability to hydrolyze proteins under acidic conditions below pH 7.
Contemplated acid fungal proteases include fungal proteases derived from Aspergillus, Mucor, Rhizopus, Candida, Coriolus, Endothia, Enthomophtra, Irpex, Penicillium, Sclerotiumand Torulopsis. Especially contemplated are proteases derived from Aspergillus niger (see, e.g., Koaze et al., 1964, Agr. Biol. Chem. Japan 28: 216), Aspergillus saitoi (see, e.g., Yoshida, 1954, J. Agr. Chem. Soc. Japan 28: 66), Aspergillus awamori (Hayashida et al., 1977, Agric. Biol. Chem. 42(5): 927-933, Aspergillus aculeatus (WO 95/02044), or Aspergillus oryzae, such as the pepA protease; and acidic proteases from Mucor pusillus or Mucor miehei.
Contemplated are also neutral or alkaline proteases, such as a protease derived from a strain of Bacillus. A particular protease contemplated for the invention is derived from Bacillus amyloliquefaciens and has the sequence obtainable at Swissprot as Accession No. P06832. Also contemplated are the proteases having at least 90% identity to amino acid sequence obtainable at Swissprot as Accession No. P06832 such as at least 92%, at least 95%, at least 96%, at least 97%, at least 98%, or particularly at least 99% identity.
Further contemplated are the proteases having at least 90% identity to amino acid sequence disclosed as SEQ. ID. NO: 1 in the WO 2003/048353 such as at 92%, at least 95%, at least 96%, at least 97%, at least 98%, or particularly at least 99% identity.
Also contemplated are papain-like proteases such as proteases within E. C. 3.4.22.* (cysteine protease), such as EC 3.4.22.2 (papain), EC 3.4.22.6 (chymopapain), EC 3.4.22.7 (asclepain), EC 3.4.22.14 (actinidain), EC 3.4.22.15 (cathepsin L), EC 3.4.22.25 (glycyl endopeptidase) and EC 3.4.22.30 (caricain). In an embodiment the protease is a protease preparation derived from a strain of
Aspergillus, such as Aspergillus oryzae. In another embodiment the protease is derived from a strain of Rhizomucor, preferably Rhizomucor miehei. In another contemplated embodiment the protease is a protease preparation, preferably a mixture of a proteolytic preparation derived from a strain of Aspergillus, such as Aspergillus oryzae, and a protease derived from a strain of Rhizomucor, preferably Rhizomucor mehei. Aspartic acid proteases are described in, for example, Handbook of Proteolytic Enzymes, Edited by Barrett, Rawlings and Woessner, Academic Press, San Diego, 1998, Chapter 270). Suitable examples of aspartic acid protease include, e.g., those disclosed in Berka et al., 1990, Gene 96: 313; Berka et al., 1993, Gene 125: 195-198; and Gomi et al., 1993, Biosci. Biotech. Biochem. 57: 1095-1100, which are hereby incorporated by reference.
Commercially available products include ALCALASE®, ESPERASE™, FLAVOURZYME™, PROMIX™, NEUTRASE®, RENNILASE®, NOVOZYM™ FM 2.0L, and NOVOZYM™ 50006 (available from Novozymes A/S, Denmark) and GC106™ and SPEZYME™ FAN from Genencor Int., Inc., USA.
The protease may be present in an amount of 0.0001-1 mg enzyme protein per g
DS, preferably 0.001 to 0.1 mg enzyme protein per g DS. Alternatively, the protease may be present in an amount of 0.0001 to 1 LAPU/g DS, preferably 0.001 to 0.1 LAPU/g DS and/or 0.0001 to 1 mAU-RH/g DS, preferably 0.001 to 0.1 mAU-RH/g DS or 0.1-1000 AU/kg DM (dry matter), preferably 1-100 AU/kg DS and most preferably 5-25 AU/kg DS.
Cellulolytic Enzymes
The terms "cellulolytic enzymes" as used herein are understood as comprising the cellobiohydrolases (EC 3.2.1.91 ), e.g., cellobiohydrolase I and cellobiohydrolase II, as well as the endo-glucanases (EC 3.2.1.4) and beta-glucosidases (EC 3.2.1.21 ). See relevant sections below with further description of such enzymes.
In order to be efficient, the digestion of cellulose may require several types of enzymes acting cooperatively. At least three categories of enzymes are often needed to convert cellulose into glucose: endoglucanases (EC 3.2.1.4) that cut the cellulose chains at random; cellobiohydrolases (EC 3.2.1.91 ) which cleave cellobiosyl units from the cellulose chain ends and beta-glucosidases (EC 3.2.1.21 ) that convert cellobiose and soluble cellodextrins into glucose. Among these three categories of enzymes involved in the biodegradation of cellulose, cellobiohydrolases are the key enzymes for the degradation of native crystalline cellulose. The term "cellobiohydrolase I" is defined herein as a cellulose 1 ,4-beta-cellobiosidase (also referred to as Exo-glucanase, Exo-cellobiohydrolase or 1 ,4- beta-cellobiohydrolase) activity, as defined in the enzyme class EC 3.2.1.91 , which catalyzes the hydrolysis of 1 ,4-beta-D-glucosidic linkages in cellulose and cellotetraose, by the release of cellobiose from the non-reducing ends of the chains. The definition of the term "cellobiohydrolase Il activity" is identical, except that cellobiohydrolase Il attacks from the reducing ends of the chains. The cellulolytic enzymes may comprise a carbohydrate-binding module (CBM) which enhances the binding of the enzyme to a cellulose-containing fiber and increases the efficacy of the catalytic active part of the enzyme. A CBM is defined as contiguous amino acid sequence within a carbohydrate-active enzyme with a discreet fold having carbohydrate-binding activity. For further information of CBMs see the CAZy internet server (Supra) or Tomme et al. (1995) in Enzymatic Degradation of Insoluble Polysaccharides (Saddler and Penner, eds.), Cellulose-binding domains: classification and properties, pp. 142-163, American Chemical Society, Washington.
In a preferred embodiment the cellulolytic enzymes may be a cellulolytic preparation as defined in co-pending international application PCT/US2008/065417, which is hereby incorporated by reference. In a preferred embodiment the cellulolytic preparation comprising a polypeptide having cellulolytic enhancing activity (GH61A), preferably the one disclosed in WO 2005/074656. The cellulolytic preparation may further comprise a beta-glucosidase, such as a beta-glucosidase derived from a strain of the genus Trichoderma, Aspergillus or Penicillium, including the fusion protein having beta-glucosidase activity disclosed in WO 2008/057637 (Novozymes). In an embodiment the cellulolytic preparation may also comprises a CBH II, preferably Thielavia terrestris cellobiohydrolase Il (CEL6A). In an embodiment the cellulolytic preparation also comprises a cellulase enzymes preparation, preferably the one derived from Trichoderma reesei. The cellulolytic activity may, in a preferred embodiment, be derived from a fungal source, such as a strain of the genus Trichoderma, preferably a strain of Trichoderma reesei; or a strain of the genus Humicola, such as a strain of Humicola insolens; or a strain of Chrysosporium, preferably a strain of Chrysosporium lucknowense (see e.g., US publication # 2007/0238155 from Dyadic Inc, USA). In an embodiment the cellulolytic enzyme preparation comprises a polypeptide having cellulolytic enhancing activity (GH61A) disclosed in WO 2005/074656; a cellobiohydrolase, such as Thielavia terrestris cellobiohydrolase Il (CEL6A), a beta- glucosidase (e.g., the fusion protein disclosed in WO 2008/057637) and cellulolytic enzymes, e.g., derived from Trichoderma reesei. In an embodiment the cellulolytic enzyme preparation comprises a polypeptide having cellulolytic enhancing activity (GH61A) disclosed in WO 2005/074656; a beta- glucosidase (e.g., the fusion protein disclosed in WO 2008/057637) and cellulolytic enzymes, e.g., derived from Trichoderma reesei.
In an embodiment the cellulolytic enzyme is the commercially available product CELLUCLAST® 1.5L or CELLUZYME™ available from Novozymes A/S, Denmark. A cellulolytic enzymes may be added for hydrolyzing the pre-treated lignocellulose- containing material. The cellulase may be dosed in the range from 0.1-100 FPU per gram total solids (TS), preferably 0.5-50 FPU per gram TS, especially 1-20 FPU per gram TS.
Endoglucanase (EG)
Endoglucanases (EC No. 3.2.1.4) catalyses endo hydrolysis of 1 ,4-beta-D-glycosidic linkages in cellulose, cellulose derivatives (such as carboxy methyl cellulose and hydroxy ethyl cellulose), lichenin, beta-1 ,4 bonds in mixed beta-1 ,3 glucans such as cereal beta-D- glucans or xyloglucans and other plant material containing cellulosic parts. The authorized name is endo-1 ,4-beta-D-glucan 4-glucano hydrolase, but the abbreviated term endoglucanase is used in the present specification. Endoglucanase activity may be determined using carboxymethyl cellulose (CMC) hydrolysis according to the procedure of Ghose, 1987, Pure and Appl. Chem. 59: 257-268.
In a preferred embodiment endoglucanases may be derived from a strain of the genus Trichoderma, preferably a strain of Trichoderma reesei; a strain of the genus Humicola, such as a strain of Humicola insolens; or a strain of Chrysosporium, preferably a strain of Chrysosporium lucknowense.
Cellobiohvdrolase (CBH) The term "cellobiohydrolase" means a 1 ,4-beta-D-glucan cellobiohydrolase (E. C.
3.2.1.91 ), which catalyzes the hydrolysis of 1 ,4-beta-D-glucosidic linkages in cellulose, cellooligosaccharides, or any beta-1 ,4-linked glucose containing polymer, releasing cellobiose from the reducing or non-reducing ends of the chain.
Examples of cellobiohydroloses are mentioned above including CBH I and CBH Il from Trichoderma reseei; Humicola insolens and CBH Il from Thielavia terrestris cellobiohydrolase (CELL6A)
Cellobiohydrolase activity may be determined according to the procedures described by Lever et al., 1972, Anal. Biochem. 47: 273-279 and by van Tilbeurgh et al., 1982, FEBS
Letters 149: 152-156; van Tilbeurgh and Claeyssens, 1985, FEBS Letters 187: 283-288. The Lever et al. method is suitable for assessing hydrolysis of cellulose in corn stover and the method of van Tilbeurgh et al. is suitable for determining the cellobiohydrolase activity on a fluorescent disaccharide derivative.
Beta-glucosidase One or more beta-glucosidases (often referred to as "cellobiases") may be present during hydrolysis. The term "beta-glucosidase" means a beta-D-glucoside glucohydrolase (E. C. 3.2.1.21 ), which catalyzes the hydrolysis of terminal non-reducing beta-D-glucose residues with the release of beta-D-glucose. For purposes of the present invention, beta-glucosidase activity is determined according to the basic procedure described by Venturi et al., 2002, J. Basic Microbiol. 42: 55-66, except different conditions were employed as described herein. One unit of beta-glucosidase activity is defined as 1.0 μmole of p-nitrophenol produced per minute at 500C, pH 5 from 4 mM p-nitrophenyl-beta-D-glucopyranoside as substrate in 100 mM sodium citrate, 0.01 % TWEEN® 20.
In a preferred embodiment the beta-glucosidase is of fungal origin, such as a strain of the genus Trichoderma, Aspergillus or Penicillium. In a preferred embodiment the beta- glucosidase is a derived from Trichoderma reesei, such as the beta-glucosidase encoded by the bgl1 gene (see Fig. 1 of EP 562003). In another preferred embodiment the beta- glucosidase is derived from Aspergillus oryzae (recombinantly produced in Aspergillus oryzae according to WO 02/095014), Aspergillus fumigatus (recombinantly produced in Aspergillus oryzae according to Example 22 of WO 02/095014) or Aspergillus niger (1981 , J. Appl. 3: 157-163). In another preferred embodiment the beta-glucosidase is the fusion protein disclosed in WO 2008/057637 (Novozymes).
Cellulolvtic Enhancing Activity The term "cellulolytic enhancing activity" is defined herein as a biological activity that enhances the hydrolysis of a lignocellulose derived material by proteins having cellulolytic activity. For purposes of the present invention, cellulolytic enhancing activity is determined by measuring the increase in reducing sugars or in the increase of the total of cellobiose and glucose from the hydrolysis of a lignocellulose derived material, e.g., pre-treated lignocellulose-containing material by cellulolytic protein under the following conditions: 1-50 mg of total protein/g of cellulose in PCS (pre-treated corn stover), wherein total protein is comprised of 80-99.5% w/w cellulolytic protein/g of cellulose in PCS and 0.5-20% w/w protein of cellulolytic enhancing activity for 1-7 day at 500C compared to a control hydrolysis with equal total protein loading without cellulolytic enhancing activity (1-50 mg of cellulolytic protein/g of cellulose in PCS).
The polypeptides having cellulolytic enhancing activity enhance the hydrolysis of a lignocellulose derived material catalyzed by proteins having cellulolytic activity by reducing the amount of cellulolytic enzyme required to reach the same degree of hydrolysis preferably at least 0.1 -fold, more at least 0.2-fold, more preferably at least 0.3-fold, more preferably at least 0.4-fold, more preferably at least 0.5-fold, more preferably at least 1-fold, more preferably at least 3-fold, more preferably at least 4-fold, more preferably at least 5- fold, more preferably at least 10-fold, more preferably at least 20-fold, even more preferably at least 30-fold, most preferably at least 50-fold, and even most preferably at least 100-fold.
In a preferred embodiment the hydrolysis and/or fermentation is carried out in the presence of a cellulolytic enzyme in combination with a polypeptide having enhancing activity. In a preferred embodiment the polypeptide having enhancing activity is a family
GH61A polypeptide. WO 2005/074647 discloses isolated polypeptides having cellulolytic enhancing activity and polynucleotides thereof from Thielavia terrestris. WO 2005/074656 discloses an isolated polypeptide having cellulolytic enhancing activity and a polynucleotide thereof from Thermoascus aurantiacus. U.S. Application Publication No. 2007/0077630 discloses an isolated polypeptide having cellulolytic enhancing activity and a polynucleotide thereof from Trichoderma reesei.
Hemicellulolvtic enzymes
Hemicellulose can be broken down by hemicellulases and/or acid hydrolysis to release its five and six carbon sugar components.
In an embodiment of the invention the lignocellulose derived material may be treated with one or more hemicellulases.
Any hemicellulase suitable for use in hydrolyzing hemicellulose, preferably into xylose, may be used. Preferred hemicellulases include xylanases, arabinofuranosidases, acetyl xylan esterase, feruloyl esterase, glucuronidases, galactanase, endo-galactanase, mannases, endo or exo arabinases, exo-galactanses, pectinase, xyloglucanase, or mixtures of two or more thereof. Preferably, the hemicellulase for use in the present invention is an exo-acting hemicellulase, and more preferably, the hemicellulase is an exo-acting hemicellulase which has the ability to hydrolyze hemicellulose under acidic conditions of below pH 7, preferably pH 3-7. An example of hemicellulase suitable for use in the present invention includes VISCOZYME™ (available from Novozymes A/S, Denmark).
In an embodiment the hemicellulase is a xylanase. In an embodiment the xylanase may preferably be of microbial origin, such as of fungal origin (e.g., Trichoderma, Meripilus, Humicola, Aspergillus, Fusarium) or from a bacterium (e.g., Bacillus). In a preferred embodiment the xylanase is derived from a filamentous fungus, preferably derived from a strain of Aspergillus, such as Aspergillus aculeatus (preferably XyI Il disclosed in WO 1994/021785); or a strain of Humicola, preferably Humicola lanuginosa. The xylanase may preferably be an endo-1 ,4-beta-xylanase, more preferably an endo-1 ,4-beta-xylanase of GH10 or GH11. Examples of commercial xylanases include SHEARZYME™ and BIOFEED WHEAT™ from Novozymes A/S, Denmark. Arabinofuranosidase (EC 3.2.1.55) catalyzes the hydrolysis of terminal non-reducing alpha-L-arabinofuranoside residues in alpha-L-arabinosides.
Galactanase (EC 3.2.1.89), arabinogalactan endo-1 ,4-beta-galactosidase, catalyses the endohydrolysis of 1 ,4-D-galactosidic linkages in arabinogalactans. Pectinase (EC 3.2.1.15) catalyzes the hydrolysis of 1 ,4-alpha-D-galactosiduronic linkages in pectate and other galacturonans.
Xyloglucanase catalyzes the hydrolysis of xyloglucan.
The hemicellulase may be added in an amount effective to hydrolyze hemicellulose, such as, in amounts from about 0.001 to 0.5 wt.-% of total solids (TS), more preferably from about 0.05 to 0.5 wt.-% of TS.
Xylanases may be added in amounts of 0.001-1.0 g/kg DM (dry matter) substrate, preferably in the amounts of 0.005-0.5 g/kg DM substrate, and most preferably from 0.05-0.10 g/kg DM substrate.
Composition
In this aspect the invention relates to a composition comprising one or more TRP channel agonist compounds and one or more enzymes and/or one or more fermenting organisms.
A non-exhaustive list of TRP channel agonist compounds can be found above in the "TRP channel and TRP superfamily" section above.
In an embodiment the enzyme(s) is(are) one or more hydrolases (class EC 3 according to Enzyme Nomenclature) selected from the group consisting of cellulase, hemicellulase, endoglucanase, beta-glucosidase, cellobiohydrolase, xylanase, alpha- amylase, alpha-glucosidases, glucoamylase, and proteases, or a mixture thereof. The composition may also comprise a fermenting organism, such as a yeast, or another fermenting organism mentioned in the "Fermenting Organism" section above.
Use
In this aspect the invention relates to the use of one or more TRP channel agonist compounds for propagating fermenting organisms such as yeast.
In invention also relates to the use of one or more TRP channel agonist compounds in a fermentation process, preferably a process of the invention.
The invention described and claimed herein is not to be limited in scope by the specific embodiments herein disclosed, since these embodiments are intended as illustrations of several aspects of the invention. Any equivalent embodiments are intended to be within the scope of this invention. Indeed, various modifications of the invention in addition to those shown and described herein will become apparent to those skilled in the art from the foregoing description. Such modifications are also intended to fall within the scope of the appended claims. In the case of conflict, the present disclosure, including definitions will be controlling.
Various references are cited herein, the disclosures of which are incorporated by reference in their entireties.
MATERIALS & METHODS Methods:
Identity: The relatedness between two amino acid sequences or between two nucleotide sequences is described by the parameter "identity".
For purposes of the present invention, the degree of identity between two amino acid sequences is determined using the Needleman-Wunsch algorithm (Needleman and Wunsch, 1970, J. MoI. Biol. 48: 443-453) as implemented in the Needle program of the EMBOSS package (EMBOSS: The European Molecular Biology Open Software Suite, Rice et al., 2000, Trends in Genetics 16: 276-277), preferably version 3.0.0 or later. The optional parameters used are gap open penalty of 10, gap extension penalty of 0.5, and the EBLOSUM62 (EMBOSS version of BLOSUM62) substitution matrix. The output of Needle labeled "longest identity" (obtained using the -nobrief option) is used as the percent identity and is calculated as follows:
(Identical Residues x 100)/(Length of Alignment - Total Number of Gaps in Alignment)
For purposes of the present invention, the degree of identity between two deoxyribonucleotide sequences is determined using the Needleman-Wunsch algorithm (Needleman and Wunsch, 1970, supra) as implemented in the Needle program of the EMBOSS package (EMBOSS: The European Molecular Biology Open Software Suite, Rice et al., 2000, supra), preferably version 3.0.0 or later. The optional parameters used are gap open penalty of 10, gap extension penalty of 0.5, and the EDNAFULL (EMBOSS version of NCBI NUC4.4) substitution matrix. The output of Needle labeled "longest identity" (obtained using the -nobrief option) is used as the percent identity and is calculated as follows:
(Identical Deoxyribonucleotides x 100)/(Length of Alignment - Total Number of Gaps in Alignment) Glucoamylase activity (AGU)
The Novo Glucoamylase Unit (AGU) is defined as the amount of enzyme, which hydrolyzes 1 micromole maltose per minute under the standard conditions 37°C, pH 4.3, substrate: maltose 23.2 mM, buffer: acetate 0.1 M, reaction time 5 minutes.
An autoanalyzer system may be used. Mutarotase is added to the glucose dehydrogenase reagent so that any alpha-D-glucose present is turned into beta-D-glucose. Glucose dehydrogenase reacts specifically with beta-D-glucose in the reaction mentioned above, forming NADH which is determined using a photometer at 340 nm as a measure of the original glucose concentration.
Figure imgf000036_0001
Figure imgf000036_0002
A folder (EB-SM-0131.02/01 ) describing this analytical method in more detail is available on request from Novozymes A/S, Denmark, which folder is hereby included by reference.
Alpha-amylase activity (KNU)
The alpha-amylase activity may be determined using potato starch as substrate. This method is based on the break-down of modified potato starch by the enzyme, and the reaction is followed by mixing samples of the starch/enzyme solution with an iodine solution. Initially, a blackish-blue color is formed, but during the break-down of the starch the blue color gets weaker and gradually turns into a reddish-brown, which is compared to a colored glass standard.
One Kilo Novo alpha amylase Unit (KNU) is defined as the amount of enzyme which, under standard conditions (Ae., at 37°C +/- 0.05; 0.0003 M Ca2+; and pH 5.6) dextrinizes 5260 mg starch dry substance Merck Amylum solubile.
A folder EB-SM-0009.02/01 describing this analytical method in more detail is available upon request to Novozymes A/S, Denmark, which folder is hereby included by reference.
Acid alpha-amylase activity (AFAU)
When used according to the present invention the activity of an acid alpha-amylase may be measured in FAU-F (Rjngal Alpha-Amylase ]Jnit) or AFAU (Acid Fungal Alpha- amylase Units).
Determination of FAU-F
FAU-F Fungal Alpha-Amylase LJnits (Fungamyl) is measured relative to an enzyme standard of a declared strength.
Figure imgf000037_0001
A folder (EB-SM-0216.02) describing this standard method in more detail is available on request from Novozymes A/S, Denmark, which folder is hereby included by reference.
Acid alpha-amylase activity (AFAU)
Acid alpha-amylase activity may be measured in AFAU (Acid Fungal Alpha-amylase Units), which are determined relative to an enzyme standard. 1 AFAU is defined as the amount of enzyme which degrades 5.260 mg starch dry matter per hour under the below mentioned standard conditions.
Acid alpha-amylase, an endo-alpha-amylase (1 ,4-alpha-D-glucan-glucanohydrolase, E. C. 3.2.1.1 ) hydrolyzes alpha-1 ,4-glucosidic bonds in the inner regions of the starch molecule to form dextrins and oligosaccharides with different chain lengths. The intensity of color formed with iodine is directly proportional to the concentration of starch. Amylase activity is determined using reverse colorimetry as a reduction in the concentration of starch under the specified analytical conditions.
ALPHA - AMYLASE STARCH + IODINE 40 : , pH 2,5 > DEXTRINS + OLIGOSACCHARIDES λ = 590 nm blue/violet t = 23 sec. decoloration
Standard conditions/reaction conditions:
Substrate: Soluble starch, approx. 0.17 g/L
Buffer: Citrate, approx. 0.03 M
Iodine (I2): 0.03 g/L
CaCI2: 1.85 mM pH: 2.50 ± 0.05
Incubation temperature: 400C
Reaction time: 23 seconds
Wavelength: 590nm
Enzyme concentration: 0.025 AFAU/mL
Enzyme working range: 0.01-0.04 AFAU/mL
A folder EB-SM-0259.02/01 describing this analytical method in more detail is available upon request to Novozymes A/S, Denmark, which folder is hereby included by reference.
Measurement of Cellulase Activity Using Filter Paper Assay (FPU assay)
1. Source of Method 1.1 The method is disclosed in a document entitled "Measurement of Cellulase Activities" by Adney and Baker, 1996, Laboratory Analytical Procedure, LAP-006, National Renewable Energy Laboratory (NREL). It is based on the IUPAC method for measuring cellulase activity (Ghose, 1987, Measurement of Cellulase Activities, Pure & Appl. Chem. 59: 257- 268. 2. Procedure
2.1 The method is carried out as described by Adney and Baker, 1996, supra, except for the use of a 96 well plates to read the absorbance values after color development, as described below. 2.2 Enzyme Assay Tubes:
2.2.1 A rolled filter paper strip (#1 Whatman; 1 X 6 cm; 50 mg) is added to the bottom of a test tube (13 X 100 mm).
2.2.2 To the tube is added 1.0 ml. of 0.05 M Na-citrate buffer (pH 4.80).
2.2.3 The tubes containing filter paper and buffer are incubated 5 min. at 500C (± 0.10C) in a circulating water bath.
2.2.4 Following incubation, 0.5 ml. of enzyme dilution in citrate buffer is added to the tube.
Enzyme dilutions are designed to produce values slightly above and below the target value of 2.0 mg glucose.
2.2.5 The tube contents are mixed by gently vortexing for 3 seconds. 2.2.6 After vortexing, the tubes are incubated for 60 mins. at 500C (± 0.10C) in a circulating water bath. 2.2.7 Immediately following the 60 min. incubation, the tubes are removed from the water bath, and 3.0 ml. of DNS reagent is added to each tube to stop the reaction. The tubes are vortexed 3 seconds to mix. 2.3 Blank and Controls
2.3.1 A reagent blank is prepared by adding 1.5 ml. of citrate buffer to a test tube.
2.3.2 A substrate control is prepared by placing a rolled filter paper strip into the bottom of a test tube, and adding 1.5 ml. of citrate buffer.
2.3.3 Enzyme controls are prepared for each enzyme dilution by mixing 1.0 ml. of citrate buffer with 0.5 ml. of the appropriate enzyme dilution.
2.3.4 The reagent blank, substrate control, and enzyme controls are assayed in the same manner as the enzyme assay tubes, and done along with them.
2.4 Glucose Standards
2.4.1 A 100 ml. stock solution of glucose (10.0 mg/mL) is prepared, and 5 ml. aliquots are frozen. Prior to use, aliquots are thawed and vortexed to mix.
2.4.2 Dilutions of the stock solution are made in citrate buffer as follows: G1 = 1.0 ml. stock + 0.5 ml. buffer = 6.7 mg/mL = 3.3 mg/0.5 mL G2 = 0.75 ml. stock + 0.75 ml. buffer = 5.0 mg/mL = 2.5 mg/0.5 mL G3 = 0.5 mL stock + 1.O mL buffer = 3.3 mg/mL = 1.7 mg/0.5 mL G4 = 0.2 mL stock + 0.8 mL buffer = 2.0 mg/mL = 1.0 mg/0.5 mL 2.4.3 Glucose standard tubes are prepared by adding 0.5 mL of each dilution to 1.0 mL of citrate buffer.
2.4.4 The glucose standard tubes are assayed in the same manner as the enzyme assay tubes, and done along with them. 2.5 Color Development
2.5.1 Following the 60 min. incubation and addition of DNS, the tubes are all boiled together for 5 mins. in a water bath.
2.5.2 After boiling, they are immediately cooled in an ice/water bath.
2.5.3 When cool, the tubes are briefly vortexed, and the pulp is allowed to settle. Then each tube is diluted by adding 50 microL from the tube to 200 microL of ddH2O in a
96-well plate. Each well is mixed, and the absorbance is read at 540 nm. 2.6 Calculations (examples are given in the NREL document)
2.6.1 A glucose standard curve is prepared by graphing glucose concentration (mg/0.5 mL) for the four standards (G1-G4) vs. A540. This is fitted using a linear regression (Prism Software), and the equation for the line is used to determine the glucose produced for each of the enzyme assay tubes.
2.6.2 A plot of glucose produced (mg/0.5 mL) vs. total enzyme dilution is prepared, with the Y-axis (enzyme dilution) being on a log scale.
2.6.3 A line is drawn between the enzyme dilution that produced just above 2.0 mg glucose and the dilution that produced just below that. From this line, it is determined the enzyme dilution that would have produced exactly 2.0 mg of glucose.
2.6.4 The Filter Paper Units/mL (FPU/mL) are calculated as follows: FPU/mL = 0.37/ enzyme dilution producing 2.0 mg glucose
Protease Assay method - AU(RH)
The proteolytic activity may be determined with denatured hemoglobin as substrate. In the Anson-Hemoglobin method for the determination of proteolytic activity denatured hemoglobin is digested, and the undigested hemoglobin is precipitated with trichloroacetic acid (TCA). The amount of TCA soluble product is determined with phenol reagent, which gives a blue color with tyrosine and tryptophan.
One Anson Unit (AU-RH) is defined as the amount of enzyme which under standard conditions (i.e., 25°C, pH 5.5 and 10 min. reaction time) digests hemoglobin at an initial rate such that there is liberated per minute an amount of TCA soluble product which gives the same color with phenol reagent as one milliequivalent of tyrosine. The AU(RH) method is described in EAL-SM-0350 and is available from Novozymes
A/S Denmark on request. Proteolytic Activity (AU)
The proteolytic activity may be determined with denatured hemoglobin as substrate. In the Anson-Hemoglobin method for the determination of proteolytic activity denatured hemoglobin is digested, and the undigested hemoglobin is precipitated with trichloroacetic acid
(TCA). The amount of TCA soluble product is determined with phenol reagent, which gives a blue color with tyrosine and tryptophan.
One Anson Unit (AU) is defined as the amount of enzyme which under standard conditions (i.e., 25°C, pH 7.5 and 10 min. reaction time) digests hemoglobin at an initial rate such that there is liberated per minute an amount of TCA soluble product which gives the same color with phenol reagent as one milliequivalent of tyrosine.
A folder AF 4/5 describing the analytical method in more detail is available upon request to Novozymes A/S, Denmark, which folder is hereby included by reference.
Protease assay method (LAPU)
1 Leucine Amino Peptidase Unit (LAPU) is the amount of enzyme which decomposes 1 microM substrate per minute at the following conditions: 26 mM of L-leucine- p-nitroanilide as substrate, 0.1 M Tris buffer (pH 8.0), 37°C, 10 minute reaction time.
LAPU is described in EB-SM-0298.02/01 available from Novozymes A/S Denmark on request.
Determination of Maltogenic Amylase activity (MANU)
One MANU (JVjaltogenic Amylase NJovo LJnit) may be defined as the amount of enzyme required to release one micro mole of maltose per minute at a concentration of 10 mg of maltotriose (Sigma M 8378) substrate per ml of 0.1 M citrate buffer, pH 5.0 at 37°C for 30 minutes.
Materials:
Yeast / Peptone Media (YP): YP media was prepared by dissolving 20 grams per liter glucose, 10 grams per liter xylose,
10 grams per liter of yeast extract, and 20 grams per liter of peptone in distilled water, followed by sterile filtration to remove microbial contaminants.
Yeast Preparation:
(Yeast #1 ) RED STAR™ available from Red Star/Lesaffre, USA (Yeast #2) RWB218 was received from Royal Nedalco/The Netherlands and is described in
Kuyper et al., 2005, FEMS Yeast Research 5: 925-934. Yeasts were propagated overnight in YP media. The yeasts were dosed into the fermentations at a pitch of 0.25 g cells per liter.
Cellulase preparation A: Cellulolytic composition comprising a polypeptide having cellulolytic enhancing activity (GH61A) disclosed in WO 2005/074656; a beta-glucosidase (fusion protein disclosed in WO 2008/057637) and cellulolytic enzymes preparation derived from Trichoderma reesei. Cellulase preparation A is disclosed in co-pending application
PCT/US2008/065417.
Biomass Substrate:
Unwashed pre-treated corn stover (PCS): Acid-catalyzed, steam-exploded obtained from The National Renewable Energy Laboratory, Golden, CO.
Glucoamylase (AMG A): Glucoamylase derived from Trametes cingulata disclosed in SEQ ID
NO: 2 in WO 2006/069289 and available from Novozymes A/S.
Alpha-Amylase A (AA1 ): Hybrid alpha-amylase consisting of Rhizomucor pusillus alpha- amylase with Aspergillus niger glucoamylase linker and SBD disclosed as V039 in Table 5 in WO 2006/069290 (Novozymes A/S).
Examples Example 1
Effect of capsaicin on ethanol yield from combination of alpha-amylase (AA 1 ) and glucoamylase (AMG A) in one-step simultaneous saccharification and fermentation (SSF) process
All treatments were evaluated via mini-scale fermentations. 410 g of ground yellow dent corn (with an average particle size around 0.5 mm) was added to 590 g tap water. This mixture was supplemented with 3.0 ml 1 g/L penicillin and 1 g of urea. The pH of this slurry was adjusted to 4.5 with 40% H2SO4. Dry solid (DS) level was determined to be around 35 wt. %. Approximately 5 g of this slurry was added to 20 ml vials. Each vial was dosed with the appropriate amount of enzyme dosage shown in table below followed by addition of 200 micro liters yeast propagate/5 g slurry. Actual enzyme dosages were based on the exact weight of corn slurry in each vial. Vials were incubated at 32°C. Nine replicate fermentations of each treatment were run. Three replicates were selected for 24 hours, 48 hours and 70 hours time point analysis. Vials were vortexed at 24, 48 and 70 hours and analyzed by HPLC. The HPLC preparation consisted of stopping the reaction by addition of 50 micro liters of 40% H2SO4, centrifuging, and filtering through a 0.45 micrometer filter. Samples were stored at 4°C until analysis. Agilent™ 1 100 HPLC system coupled with Rl detector was used to determine ethanol and oligosaccharides concentration. The separation column was aminex HPX-87H ion exclusion column (300 mm x 7.8 mm) from BioRad™. The results for Experiment 1 are summarized in Figure 1.
Experiment 1
AA 1 AMG A Capsaicin
(FAU- (AG U/g (micro
Treatments F/gDS) DS) molar/gDS)
1 AA 1 + AMG A 0.0475 0.50
2 AA 1 + AMG A + Capsaicin 0.0475 0.50 5
3 AA 1 + AMG A + Capsaicin 0.0475 0.50 10
4 AA 1 + AMG A + Capsaicin 0.0475 0.50 20
Example 2
Effect of capsaicin and icilin on ethanol yield from PCS fermented with two different yeast strains
Pretreatment of Fully Unwashed Pretreated Corn Stover (fuwPCS)
Dilute acid steam exploded corn stover (PCS) was diluted with water and adjusted to pH 5.0 with NH4OH. The total solids (TS) level was 20 wt.%. This sample was then saccharified for 63 hours at 500C with Cellulolytic Preparation A. Penicillin was added at a rate of 1 g/L, also added prior to saccharification was citrate buffer at a rate of 5OmL of 1 M citrate buffer per 100 ml of substrate. Following the saccharification step, the sample was filtered via a 0.2 micron Nalgene vacuum filter system (Product # 8-0000-43-0803) to remove the solids and used for fermentation. The fuwPCS was then pipetted into separate sterile, 20 milliliter glass vials equipped with screw top lids fitted with a small CO2 vent hole and 25 gauge needle.
Icilin Dosing
Three separate stock solutions were prepared for dosing into the fermentation vials in which icilin was diluted with DMSO. The final dosages of icilin tested in the experiment were 10,
30, and 100 micromolar.
Capsaicin Dosing
Three separate stock solutions were prepared for dosing into the fermentation vials in which capsaicin was diluted with DMSO. The final dosages of capsaicin tested in the experiment were 10, 30, and 100 micromolar.
Fermentation
Fermentation vials were filled with 1.80 milliliters of 20% TS fuwPCS, 0.95 milliliters of YP media containing 70 grams per liter of glucose and 45 grams per liter of xylose, 150 microliters of yeast propagate, the appropriate amount (volume or weight) of the test compound, and sterile deionized water to a total final volume of 3.0 milliliters. Fermentation vials were capped with screw-top lids with septa into which a 25 gauge needle was placed for CO2 release. The vials were placed into a rack and inserted into a tabletop shaker and agitated at 150 rpm for 30 hours at a temperature of 300C. All fermentations were run in triplicate. The control contained the same amount of DMSO as the treated samples. Analysis
After 30 hours of fermentation, an aliquot of each vial was removed and centrifuged to remove yeast cells. The supernatant was then filtered through a 0.2 micron syringe filter and the content of ethanol in each sample was measured by HPLC. Results are as shown in Figures 2 (Yeast #1 ) and 3 (Yeast #2).

Claims

1. A process of fermenting plant material into a fermentation product using a fermenting organism, wherein one or more TRP channel agonist compounds is present during fermentation.
2. The process of claim 1 , wherein the agonist compound is selected from the group consisting of resiniferatoxin, piperine, olvanil, anadamide, 2-APB, camphor, 4alpha-PDD, 5'6'-EET, menthol, eucalyptol, icilin, cinnamaldehyde, allylisothiocyanate, delta9 tetra hydrocannabiol, and capsaicin, or analogues thereof.
3. The process of claim 1 or 2, wherein the agonist compound is icilin or capsaicin.
4. The process of any of claims 1-3, wherein the agonist compound is present in a concentration of 0.01-100 mM.
5. The process of any of claims 1-4, wherein the agonist compound is added before or during fermentation.
6. The process of any of claims 1-5, wherein the plant material being fermented is sugars derived from lignocellulose-containing plant material or sugars derived from starch- containing plant material, or a mixture thereof.
7. The process of any of claims 1-6, wherein the fermentation product is an alcohol.
8. A process of producing a fermentation product from starch-containing material comprising the steps of: i) liquefying starch-containing material; ii) saccharifying the liquefied material; iii) fermenting with a fermenting organism; wherein fermentation is carried out as defined in any of claims 1-7.
9. The process of claim 8, wherein steps ii) and iii) are carried out simultaneously or sequentially.
10. A process of producing a fermentation product from starch-containing material, comprising the steps of:
(a) saccharifying starch-containing material at a temperature below the initial gelatinization temperature of said starch-containing material; (b) fermenting with a fermenting organism, wherein fermentation is carried out as defined in any of claims 1-7.
11. The process of claim 10, wherein steps (a) and (b) are carried out simultaneously or sequentially.
12. The process of any of claims 16-19, wherein the starch-containing material is granular starch.
13. A process of producing a fermentation product from lignocellulose-containing material, comprising the steps of:
(a) pre-treating lignocellulose-containing material;
(b) hydrolyzing the material obtained in step (a);
(c) fermenting with a fermenting organism; wherein fermentation is carried out as defined in any of claims 1-7.
14. The process of claim 13, wherein hydrolysis in step (b) and fermentation in step (c) is carried out as a SSF, HHF, or SHF process.
15. A composition comprising one or more TRP channel agonist compounds, and one or more enzymes or one or more fermenting organisms.
16. The composition of claim 15, wherein the TRP channel agonist compound is an agonist for one or more members of a TRP subfamily selected from the group consisting of TRPC, TRPV, TRPA, TRPM, TRPP, TRPML, and TRPN.
17. The composition of claim 15 or 16, wherein the TRP channel agonist compound is selected from the group consisting of resiniferatoxin, piperine, olvanil, anadamide, 2-APB, camphor, 4alpha-PDD, 5'6'-EET, menthol, eucalyptol, icilin, cinnamaldehyde, allylisothiocyanate, delta9 tetra hydrocannabiol, and capsaicin, or analogues thereof.
18. The composition of any of claims 15-17, wherein the agonist compound is icilin or capsaicin.
19. The composition of any of claims 15-18, wherein the enzyme is one or more hydrolases selected from the group consisting of cellulase, hemicellulase, endoglucanase, beta- glucosidase, cellobiohydrolase, xylanase, alpha-amylase, alpha-glucosidases, glucoamylase, and proteases, or a mixture thereof.
20. Use of one or more TRP channel agonist compounds for propagating fermenting organisms.
PCT/US2009/069773 2008-12-31 2009-12-30 Processes of producing fermentation products WO2010078392A2 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US14170908P 2008-12-31 2008-12-31
US61/141,709 2008-12-31

Publications (2)

Publication Number Publication Date
WO2010078392A2 true WO2010078392A2 (en) 2010-07-08
WO2010078392A3 WO2010078392A3 (en) 2011-01-13

Family

ID=42310593

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2009/069773 WO2010078392A2 (en) 2008-12-31 2009-12-30 Processes of producing fermentation products

Country Status (1)

Country Link
WO (1) WO2010078392A2 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10159268B2 (en) 2013-02-08 2018-12-25 General Mills, Inc. Reduced sodium food products

Citations (39)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1984002921A2 (en) 1983-01-28 1984-08-02 Cetus Corp Glucoamylase cdna
EP0135138A2 (en) 1983-08-17 1985-03-27 Cpc International Inc. A novel thermostable glucoamylase and method for its production
WO1986001831A1 (en) 1984-09-18 1986-03-27 Michigan Biotechnology Institute Thermostable starch converting enzymes
US4587215A (en) 1984-06-25 1986-05-06 Uop Inc. Highly thermostable amyloglucosidase
USRE32153E (en) 1978-09-01 1986-05-20 Cpc International Inc. Highly thermostable glucoamylaseand process for its production
US4598048A (en) 1983-03-25 1986-07-01 Novo Industri A/S Preparation of a maltogenic amylase enzyme
US4727026A (en) 1985-11-26 1988-02-23 Godo Shusei Co., Ltd. Method for direct saccharification of raw starch using enzyme produced by a basidiomycete belonging to the genus Corticium
WO1989001969A1 (en) 1987-09-04 1989-03-09 Novo-Nordisk A/S Process for the production of protein products in aspergillus and promoters for use in aspergillus
WO1992000381A1 (en) 1990-06-29 1992-01-09 Novo Nordisk A/S Enzymatic hydrolysis of starch to glucose, using a genetically engineered enzyme
EP0562003A1 (en) 1990-12-10 1993-09-29 Genencor International, Inc. IMPROVED SACCHARIFICATION OF CELLULOSE BY CLONING AND AMPLIFICATION OF THE $g(b)-GLUCOSIDASE GENE OF TRICHODERMA REESEI
WO1994021785A1 (en) 1993-03-10 1994-09-29 Novo Nordisk A/S Enzymes with xylanase activity from aspergillus aculeatus
WO1995002044A1 (en) 1993-07-06 1995-01-19 Novo Nordisk A/S An enzyme with protease activity
WO1996023874A1 (en) 1995-02-03 1996-08-08 Novo Nordisk A/S A method of designing alpha-amylase mutants with predetermined properties
WO1996023873A1 (en) 1995-02-03 1996-08-08 Novo Nordisk A/S Amylase variants
WO1997041213A1 (en) 1996-04-30 1997-11-06 Novo Nordisk A/S α-AMYLASE MUTANTS
WO1999019467A1 (en) 1997-10-13 1999-04-22 Novo Nordisk A/S α-AMYLASE MUTANTS
WO1999028448A1 (en) 1997-11-26 1999-06-10 Novo Nordisk A/S Thermostable glucoamylase
WO2000004136A1 (en) 1998-07-15 2000-01-27 Novozymes A/S Glucoamylase variants
US6093562A (en) 1996-02-05 2000-07-25 Novo Nordisk A/S Amylase variants
WO2000060059A2 (en) 1999-03-30 2000-10-12 NovozymesA/S Alpha-amylase variants
US6162628A (en) 1998-02-27 2000-12-19 Novo Nordisk A/S Maltogenic alpha-amylase variants
WO2001004273A2 (en) 1999-07-09 2001-01-18 Novozymes A/S Glucoamylase variant
WO2002010355A2 (en) 2000-08-01 2002-02-07 Novozymes A/S Alpha-amylase mutants with altered stability
US20020164730A1 (en) 2000-02-24 2002-11-07 Centro De Investigaciones Energeticas, Medioambientales Y Tecnologicas (C.I.E.M.A.T.) Procedure for the production of ethanol from lignocellulosic biomass using a new heat-tolerant yeast
WO2002095014A2 (en) 2001-05-18 2002-11-28 Novozymes A/S Polypeptides having cellobiase activity and polynucleotides encoding same
WO2003048353A1 (en) 2001-12-07 2003-06-12 Novozymes A/S Polypeptides having protease activity and nucleic acids encoding same
WO2004055178A1 (en) 2002-12-17 2004-07-01 Novozymes A/S Thermostable alpha-amylases
WO2005003311A2 (en) 2003-06-25 2005-01-13 Novozymes A/S Enzymes for starch processing
US20050054071A1 (en) 2003-06-25 2005-03-10 Novozymes A/S Enzymes for starch processing
WO2005045018A1 (en) 2003-10-28 2005-05-19 Novozymes North America, Inc. Hybrid enzymes
WO2005074647A2 (en) 2004-01-30 2005-08-18 Novozymes Inc. Polypeptides having cellulolytic enhancing activity and polynucleotides encoding same
WO2005074656A2 (en) 2004-02-06 2005-08-18 Novozymes, Inc. Polypeptides having cellulolytic enhancing activity and polynucleotides encoding same
WO2006011900A2 (en) 2004-06-30 2006-02-02 Nokia Corporation Method and system for managing metadata
WO2006011899A1 (en) 2003-11-25 2006-02-02 L-3 Communications Security and Detection Systems Corporation Security system for detecting nuclear masses
WO2006069290A2 (en) 2004-12-22 2006-06-29 Novozymes A/S Enzymes for starch processing
WO2006110901A2 (en) 2005-04-12 2006-10-19 E. I. Du Pont De Nemours And Company Treatment of biomass to obtain fermentable sugars
US20070077630A1 (en) 2005-09-30 2007-04-05 Novozymes, Inc. Methods for enhancing the degradation or conversion of cellulosic material
US20070238155A1 (en) 1996-10-10 2007-10-11 Gusakov Alexander V Construction of highly efficient cellulase compositions for enzymatic hydrolysis of cellulose
WO2008057637A2 (en) 2006-07-21 2008-05-15 Novozymes, Inc. Methods of increasing secretion of polypeptides having biological activity

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0003318B1 (en) * 1978-01-27 1981-10-28 Chimicasa Gmbh Processing of foodstuffs and composition for the protection of microorganisms used in foodstuff-processing
US5560910A (en) * 1994-08-26 1996-10-01 Crandall; Wilson T. Topical anti-inflammatory composition and method
FR2800614B1 (en) * 1999-11-10 2002-01-04 Top Pharm Lab COMPOSITION FOR THE TREATMENT OF RESPIRATORY INFECTIONS
EP1722812B1 (en) * 2004-02-19 2014-08-13 Novozymes North America, Inc. Liquefaction processes
MXPA06013130A (en) * 2004-05-13 2007-04-19 Novozymes North America Inc A process of producing a fermentation product.
JP2006254702A (en) * 2005-03-15 2006-09-28 Hot Planning Co Ltd Fermented food and method for producing the same
CA2653571C (en) * 2006-06-16 2014-12-30 Polymer Ventures, Inc. Composition and methods for improving the production of fermentation operations
US7514247B2 (en) * 2007-11-03 2009-04-07 Wise Landfill Recycling Mining, Inc. Systems and processes for cellulosic ethanol production

Patent Citations (44)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
USRE32153E (en) 1978-09-01 1986-05-20 Cpc International Inc. Highly thermostable glucoamylaseand process for its production
WO1984002921A2 (en) 1983-01-28 1984-08-02 Cetus Corp Glucoamylase cdna
US4598048A (en) 1983-03-25 1986-07-01 Novo Industri A/S Preparation of a maltogenic amylase enzyme
US4604355A (en) 1983-03-25 1986-08-05 Novo Industri A/S Maltogenic amylase enzyme, preparation and use thereof
EP0135138A2 (en) 1983-08-17 1985-03-27 Cpc International Inc. A novel thermostable glucoamylase and method for its production
US4587215A (en) 1984-06-25 1986-05-06 Uop Inc. Highly thermostable amyloglucosidase
WO1986001831A1 (en) 1984-09-18 1986-03-27 Michigan Biotechnology Institute Thermostable starch converting enzymes
US4727026A (en) 1985-11-26 1988-02-23 Godo Shusei Co., Ltd. Method for direct saccharification of raw starch using enzyme produced by a basidiomycete belonging to the genus Corticium
WO1989001969A1 (en) 1987-09-04 1989-03-09 Novo-Nordisk A/S Process for the production of protein products in aspergillus and promoters for use in aspergillus
WO1992000381A1 (en) 1990-06-29 1992-01-09 Novo Nordisk A/S Enzymatic hydrolysis of starch to glucose, using a genetically engineered enzyme
EP0562003A1 (en) 1990-12-10 1993-09-29 Genencor International, Inc. IMPROVED SACCHARIFICATION OF CELLULOSE BY CLONING AND AMPLIFICATION OF THE $g(b)-GLUCOSIDASE GENE OF TRICHODERMA REESEI
WO1994021785A1 (en) 1993-03-10 1994-09-29 Novo Nordisk A/S Enzymes with xylanase activity from aspergillus aculeatus
WO1995002044A1 (en) 1993-07-06 1995-01-19 Novo Nordisk A/S An enzyme with protease activity
WO1996023874A1 (en) 1995-02-03 1996-08-08 Novo Nordisk A/S A method of designing alpha-amylase mutants with predetermined properties
WO1996023873A1 (en) 1995-02-03 1996-08-08 Novo Nordisk A/S Amylase variants
US6297038B1 (en) 1995-02-03 2001-10-02 Novozymes A/S Amylase variants
US6093562A (en) 1996-02-05 2000-07-25 Novo Nordisk A/S Amylase variants
WO1997041213A1 (en) 1996-04-30 1997-11-06 Novo Nordisk A/S α-AMYLASE MUTANTS
US20070238155A1 (en) 1996-10-10 2007-10-11 Gusakov Alexander V Construction of highly efficient cellulase compositions for enzymatic hydrolysis of cellulose
WO1999019467A1 (en) 1997-10-13 1999-04-22 Novo Nordisk A/S α-AMYLASE MUTANTS
US6187576B1 (en) 1997-10-13 2001-02-13 Novo Nordisk A/S α-amylase mutants
WO1999028448A1 (en) 1997-11-26 1999-06-10 Novo Nordisk A/S Thermostable glucoamylase
US6162628A (en) 1998-02-27 2000-12-19 Novo Nordisk A/S Maltogenic alpha-amylase variants
WO2000004136A1 (en) 1998-07-15 2000-01-27 Novozymes A/S Glucoamylase variants
WO2000060059A2 (en) 1999-03-30 2000-10-12 NovozymesA/S Alpha-amylase variants
WO2001004273A2 (en) 1999-07-09 2001-01-18 Novozymes A/S Glucoamylase variant
US20020164730A1 (en) 2000-02-24 2002-11-07 Centro De Investigaciones Energeticas, Medioambientales Y Tecnologicas (C.I.E.M.A.T.) Procedure for the production of ethanol from lignocellulosic biomass using a new heat-tolerant yeast
WO2002010355A2 (en) 2000-08-01 2002-02-07 Novozymes A/S Alpha-amylase mutants with altered stability
WO2002095014A2 (en) 2001-05-18 2002-11-28 Novozymes A/S Polypeptides having cellobiase activity and polynucleotides encoding same
WO2003048353A1 (en) 2001-12-07 2003-06-12 Novozymes A/S Polypeptides having protease activity and nucleic acids encoding same
WO2004055178A1 (en) 2002-12-17 2004-07-01 Novozymes A/S Thermostable alpha-amylases
WO2005003311A2 (en) 2003-06-25 2005-01-13 Novozymes A/S Enzymes for starch processing
US20050054071A1 (en) 2003-06-25 2005-03-10 Novozymes A/S Enzymes for starch processing
WO2005045018A1 (en) 2003-10-28 2005-05-19 Novozymes North America, Inc. Hybrid enzymes
WO2006011899A1 (en) 2003-11-25 2006-02-02 L-3 Communications Security and Detection Systems Corporation Security system for detecting nuclear masses
WO2005074647A2 (en) 2004-01-30 2005-08-18 Novozymes Inc. Polypeptides having cellulolytic enhancing activity and polynucleotides encoding same
WO2005074656A2 (en) 2004-02-06 2005-08-18 Novozymes, Inc. Polypeptides having cellulolytic enhancing activity and polynucleotides encoding same
WO2006011900A2 (en) 2004-06-30 2006-02-02 Nokia Corporation Method and system for managing metadata
WO2006069290A2 (en) 2004-12-22 2006-06-29 Novozymes A/S Enzymes for starch processing
WO2006069289A2 (en) 2004-12-22 2006-06-29 Novozymes North America, Inc Polypeptides having glucoamylase activity and polynucleotides encoding same
WO2006110901A2 (en) 2005-04-12 2006-10-19 E. I. Du Pont De Nemours And Company Treatment of biomass to obtain fermentable sugars
WO2006110891A2 (en) 2005-04-12 2006-10-19 E. I. Du Pont De Nemours And Company Treatment of biomass to obtain a target chemical
US20070077630A1 (en) 2005-09-30 2007-04-05 Novozymes, Inc. Methods for enhancing the degradation or conversion of cellulosic material
WO2008057637A2 (en) 2006-07-21 2008-05-15 Novozymes, Inc. Methods of increasing secretion of polypeptides having biological activity

Non-Patent Citations (41)

* Cited by examiner, † Cited by third party
Title
ADNEY; BAKER: "Measurement of Cellulase Activities", LABORATORY ANALYTICAL PROCEDURE, LAP-006, NATIONAL RENEWABLE ENERGY LABORATORY (NREL), 1996
AGRIC. BIOL. CHEM., vol. 55, no. 4, 1991, pages 941 - 949
APPL. MICROBIOL. BIOTECH., vol. 77, pages 61 - 86
BARRETT, RAWLINGS AND WOESSNER: "Handbook of Proteolytic Enzymes", 1998, ACADEMIC PRESS
BERKA ET AL., GENE, vol. 125, 1993, pages 195 - 198
BERKA ET AL., GENE, vol. 96, 1990, pages 313
BOEL ET AL., EMBO J., vol. 3, no. 5, 1984, pages 1097 - 1102
CHEN ET AL., BIOCHEM. J., vol. 301, 1994, pages 275 - 281
CHEN ET AL., PROT. ENG., vol. 8, 1995, pages 575 - 582
CHEN ET AL., PROT. ENG., vol. 9, 1996, pages 499 - 505
FIEROBE ET AL., BIOCHEMISTRY, vol. 35, 1996, pages 8698 - 8704
GHOSE, PURE AND APPL. CHEM., vol. 59, 1987, pages 257 - 268
GHOSE: "Measurement of Cellulase Activities", PURE & APPL. CHEM., vol. 59, 1987, pages 257 - 268, XP000652082
GHOSH; SINGH: "Physicochemical and biological treatments for enzymatic/microbial conversion of lignocellulosic biomass", ADV. APPL. MICROBIOL., vol. 39, 1993, pages 295 - 333, XP009102696, DOI: doi:10.1016/S0065-2164(08)70598-7
GOMI ET AL., BIOSCI. BIOTECH. BIOCHEM., vol. 57, 1993, pages 1095 - 1100
GONG; CAO; DU; TSAO: "Advances in Biochemical Engineering/Biotechnology", vol. 65, 1999, SPRINGER-VERLAG, article "Ethanol production from renewable resources", pages: 207 - 241
GORINSTEIN; LII, STARCH/STÄRKE, vol. 44, no. 12, 1992, pages 461 - 466
HAYASHIDA ET AL., AGRIC. BIOL. CHEM., vol. 42, no. 5, 1977, pages 927 - 933
HO ET AL., APPLIED AND ENVIRONMENTAL MICROBIOLOGY, 1998, pages 1852 - 1859
HSU: "Handbook on Bioethanol: Production and Utilization", 1996, TAYLOR & FRANCIS, article "Pretreatment of biomass", pages: 179 - 212
J. APPL., vol. 3, 1981, pages 157 - 163
KANEKO ET AL., J. FERMENT. BIOENG, vol. 81, 1996, pages 292 - 298
KARHUMAA ET AL., MICROBIAL CELL FACTORIES, vol. 5, 2006, pages 18
KOAZE ET AL., AGR. BIOL. CHEM. JAPAN, vol. 28, 1964, pages 216
KUYPER ET AL., FEMS YEAST RESEARCH, vol. 5, 2005, pages 925 - 934
LEVER ET AL., ANAL. BIOCHEM., vol. 47, 1972, pages 273 - 279
LI ET AL., PROTEIN ENG., vol. 10, 1997, pages 1199 - 1204
MCMILLAN: "Enzymatic Conversion of Biomass for Fuels Production", 1994, AMERICAN CHEMICAL SOCIETY, article "Pretreating lignocellulosic biomass"
MOSIER ET AL., BIORESOURCE TECHNOLOGY, vol. 96, 2005, pages 673 - 686
NAGASAKA ET AL.: "Purification and properties of the raw-starch-degrading glucoamylases from Corticium rolfsii", APPL MICROBIOL BIOTECHNOL, vol. 50, 1998, pages 323 - 330, XP002506425, DOI: doi:10.1007/s002530051299
NEEDLEMAN; WUNSCH, J. MOL. BIOL., vol. 48, 1970, pages 443 - 453
OLSSON; HAHN- HAGERDAL: "Fermentation of lignocellulosic hydrolysates for ethanol production", ENZ. MICROB. TECH., vol. 18, 1996, pages 312 - 331, XP002312595, DOI: doi:10.1016/0141-0229(95)00157-3
RICE ET AL.: "EMBOSS: The European Molecular Biology Open Software Suite", TRENDS IN GENETICS, vol. 16, 2000, pages 276 - 277, XP004200114, DOI: doi:10.1016/S0168-9525(00)02024-2
SCHELL ET AL., APPL. BIOCHEM AND BIOTECHN, vol. 105-108, 2003, pages 69 - 85
TILBEURGH ET AL., FEBS LETTERS, vol. 149, 1982, pages 152 - 156
TILBEURGH; CLAEYSSENS, FEBS LETTERS, vol. 187, 1985, pages 283 - 288
TOMME ET AL.: "Enzymatic Degradation of Insoluble Polysaccharides", 1995, AMERICAN CHEMICAL SOCIETY, article "Cellulose-binding domains: classification and properties", pages: 142 - 163
VALLANDER; ERIKSSON: "Production of ethanol from lignocellulosic materials: State of the art", ADV. BIOCHEM. ENG.LBIOTECHNOL., vol. 42, 1990, pages 63 - 95
VENTURI ET AL., J. BASIC MICROBIOL., vol. 42, 2002, pages 55 - 66
W.M. FOGARTY; C.T. KELLY, PROGRESS IN INDUSTRIAL MICROBIOLOGY, vol. 15, 1979, pages 112 - 115
YOSHIDA, J. AGR. CHEM. SOC. JAPAN, vol. 28, 1954, pages 66

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10159268B2 (en) 2013-02-08 2018-12-25 General Mills, Inc. Reduced sodium food products
US11540539B2 (en) 2013-02-08 2023-01-03 General Mills, Inc. Reduced sodium food products

Also Published As

Publication number Publication date
WO2010078392A3 (en) 2011-01-13

Similar Documents

Publication Publication Date Title
US10640794B2 (en) Processes of producing fermentation products
US20080145903A1 (en) Processes of producing fermentation products
US9399782B2 (en) Methods for producing fermentation products
US20100221805A1 (en) Methods for producing fermentation products
US20110008864A1 (en) Processes for Producing Fermentation Products
US20110008863A1 (en) Methods for Producing Fermentation Products
EP2222863B1 (en) Processes of producing fermentation products
EP2344650B1 (en) Improvement of enzymatic hydrolysis of pre-treated lignocellulose-containing material with distillers dried grains
WO2010014817A2 (en) Producing fermentation products
WO2015050809A1 (en) Processes of producing fermentation products
US20100297718A1 (en) Processes of Producing Fermentation Products
US8349592B2 (en) Producing fermentation products in the presence of aldehyde dehydrogenase
WO2010078392A2 (en) Processes of producing fermentation products
WO2015057520A1 (en) Processes of producing fermentation products
WO2015048087A1 (en) Processes of producing fermentation products

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 09797241

Country of ref document: EP

Kind code of ref document: A2

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 09797241

Country of ref document: EP

Kind code of ref document: A2