US3846238A - Fermentation process for converting hydrocarbons to proteinaceous materials - Google Patents
Fermentation process for converting hydrocarbons to proteinaceous materials Download PDFInfo
- Publication number
- US3846238A US3846238A US00289228A US28922872A US3846238A US 3846238 A US3846238 A US 3846238A US 00289228 A US00289228 A US 00289228A US 28922872 A US28922872 A US 28922872A US 3846238 A US3846238 A US 3846238A
- Authority
- US
- United States
- Prior art keywords
- strain
- yeast
- hydrocarbon
- candida lipolytica
- nutrient medium
- Prior art date
- Legal status (The legal status 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 status listed.)
- Expired - Lifetime
Links
- 229930195733 hydrocarbon Natural products 0.000 title claims abstract description 28
- 150000002430 hydrocarbons Chemical class 0.000 title claims abstract description 27
- 239000000463 material Substances 0.000 title claims abstract description 8
- 238000000855 fermentation Methods 0.000 title description 7
- 230000004151 fermentation Effects 0.000 title description 7
- 239000004215 Carbon black (E152) Substances 0.000 claims abstract description 20
- 241000235015 Yarrowia lipolytica Species 0.000 claims abstract description 16
- 238000000034 method Methods 0.000 claims abstract description 15
- 235000015097 nutrients Nutrition 0.000 claims abstract description 11
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 6
- 239000001301 oxygen Substances 0.000 claims abstract description 6
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 6
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical group [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 5
- 238000006243 chemical reaction Methods 0.000 claims abstract description 4
- 240000004808 Saccharomyces cerevisiae Species 0.000 description 27
- 230000001580 bacterial effect Effects 0.000 description 8
- 239000002609 medium Substances 0.000 description 8
- 235000019750 Crude protein Nutrition 0.000 description 7
- 125000004432 carbon atom Chemical group C* 0.000 description 7
- 239000007789 gas Substances 0.000 description 7
- 238000004519 manufacturing process Methods 0.000 description 7
- WQZGKKKJIJFFOK-GASJEMHNSA-N Glucose Natural products OC[C@H]1OC(O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-GASJEMHNSA-N 0.000 description 5
- 238000010790 dilution Methods 0.000 description 5
- 239000012895 dilution Substances 0.000 description 5
- 239000003208 petroleum Substances 0.000 description 5
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 4
- 239000002028 Biomass Substances 0.000 description 4
- 238000011109 contamination Methods 0.000 description 4
- 239000008103 glucose Substances 0.000 description 4
- 239000003350 kerosene Substances 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- 239000000758 substrate Substances 0.000 description 4
- 229920001817 Agar Polymers 0.000 description 3
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 3
- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerine Chemical compound OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 description 3
- 239000001888 Peptone Substances 0.000 description 3
- 108010080698 Peptones Proteins 0.000 description 3
- JZRWCGZRTZMZEH-UHFFFAOYSA-N Thiamine Natural products CC1=C(CCO)SC=[N+]1CC1=CN=C(C)N=C1N JZRWCGZRTZMZEH-UHFFFAOYSA-N 0.000 description 3
- 239000008272 agar Substances 0.000 description 3
- 238000009835 boiling Methods 0.000 description 3
- 229940041514 candida albicans extract Drugs 0.000 description 3
- 229910052799 carbon Inorganic materials 0.000 description 3
- 239000006071 cream Substances 0.000 description 3
- 239000002808 molecular sieve Substances 0.000 description 3
- 235000019319 peptone Nutrition 0.000 description 3
- URGAHOPLAPQHLN-UHFFFAOYSA-N sodium aluminosilicate Chemical compound [Na+].[Al+3].[O-][Si]([O-])=O.[O-][Si]([O-])=O URGAHOPLAPQHLN-UHFFFAOYSA-N 0.000 description 3
- 239000012138 yeast extract Substances 0.000 description 3
- 229910021529 ammonia Inorganic materials 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 239000004202 carbamide Substances 0.000 description 2
- 238000010924 continuous production Methods 0.000 description 2
- 230000000877 morphologic effect Effects 0.000 description 2
- FGIUAXJPYTZDNR-UHFFFAOYSA-N potassium nitrate Chemical compound [K+].[O-][N+]([O-])=O FGIUAXJPYTZDNR-UHFFFAOYSA-N 0.000 description 2
- 108010027322 single cell proteins Proteins 0.000 description 2
- KDYFGRWQOYBRFD-UHFFFAOYSA-N succinic acid Chemical compound OC(=O)CCC(O)=O KDYFGRWQOYBRFD-UHFFFAOYSA-N 0.000 description 2
- 235000000346 sugar Nutrition 0.000 description 2
- 150000008163 sugars Chemical class 0.000 description 2
- 239000008399 tap water Substances 0.000 description 2
- 235000020679 tap water Nutrition 0.000 description 2
- 235000019157 thiamine Nutrition 0.000 description 2
- 239000011721 thiamine Substances 0.000 description 2
- XSQUKJJJFZCRTK-UHFFFAOYSA-N urea group Chemical group NC(=O)N XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 241000589291 Acinetobacter Species 0.000 description 1
- 241000894006 Bacteria Species 0.000 description 1
- 239000004386 Erythritol Substances 0.000 description 1
- UNXHWFMMPAWVPI-UHFFFAOYSA-N Erythritol Natural products OCC(O)C(O)CO UNXHWFMMPAWVPI-UHFFFAOYSA-N 0.000 description 1
- 241000588722 Escherichia Species 0.000 description 1
- GXCLVBGFBYZDAG-UHFFFAOYSA-N N-[2-(1H-indol-3-yl)ethyl]-N-methylprop-2-en-1-amine Chemical compound CN(CCC1=CNC2=C1C=CC=C2)CC=C GXCLVBGFBYZDAG-UHFFFAOYSA-N 0.000 description 1
- 229910002651 NO3 Inorganic materials 0.000 description 1
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 description 1
- 241000589516 Pseudomonas Species 0.000 description 1
- WQZGKKKJIJFFOK-VFUOTHLCSA-N beta-D-glucose Chemical compound OC[C@H]1O[C@@H](O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-VFUOTHLCSA-N 0.000 description 1
- 230000001413 cellular effect Effects 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 239000000356 contaminant Substances 0.000 description 1
- 239000006783 corn meal agar Substances 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 239000008121 dextrose Substances 0.000 description 1
- UNXHWFMMPAWVPI-ZXZARUISSA-N erythritol Chemical compound OC[C@H](O)[C@H](O)CO UNXHWFMMPAWVPI-ZXZARUISSA-N 0.000 description 1
- 229940009714 erythritol Drugs 0.000 description 1
- 235000019414 erythritol Nutrition 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000003337 fertilizer Substances 0.000 description 1
- 238000011081 inoculation Methods 0.000 description 1
- 239000002054 inoculum Substances 0.000 description 1
- 230000000813 microbial effect Effects 0.000 description 1
- 238000007747 plating Methods 0.000 description 1
- 235000010333 potassium nitrate Nutrition 0.000 description 1
- 239000004323 potassium nitrate Substances 0.000 description 1
- 230000028070 sporulation Effects 0.000 description 1
- 239000001384 succinic acid Substances 0.000 description 1
- KYMBYSLLVAOCFI-UHFFFAOYSA-N thiamine Chemical compound CC1=C(CCO)SCN1CC1=CN=C(C)N=C1N KYMBYSLLVAOCFI-UHFFFAOYSA-N 0.000 description 1
- 229960003495 thiamine Drugs 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12N—MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
- C12N1/00—Microorganisms, e.g. protozoa; Compositions thereof; Processes of propagating, maintaining or preserving microorganisms or compositions thereof; Processes of preparing or isolating a composition containing a microorganism; Culture media therefor
- C12N1/26—Processes using, or culture media containing, hydrocarbons
-
- Y—GENERAL 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
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S435/00—Chemistry: molecular biology and microbiology
- Y10S435/8215—Microorganisms
- Y10S435/911—Microorganisms using fungi
- Y10S435/921—Candida
- Y10S435/923—Candida lipolytica
Definitions
- the present invention is concerned with improvements in and relating to a continuous process for converting hydrocarbons to proteinaceous material.
- the invention relates to a continuous process for the production of single cell protein by cultivating a new yeast strain on a hydrocarbon as the carbon substrate.
- the present invention is a process for the conversion of a hydrocarbon into a proteinaceous material which comprises continuously cultivating Candida lipolytica strain C.B.S. number 6331 in the presence of a straight chain hydrocarbon having at least 10 carbon atoms per molecule, an aqueous nutrient medium and a gas containing free oxygen.
- Preferred hydrocarbons are normal parafiins recovered from petroleum fractions in the kerosine or gas oil boiling ranges.
- these hydrocarbons are gas oil boiling range normal paraflins containing 11 to 23 and mainly 14 to 21 carbon atoms per molecule and kerosine boiling range normal parafiins containing 10 to 13 carbon atoms per molecule.
- Straight chain hydrocarbons obtained from petroleum feedstocks by molecular sieve treatment are most suitable.
- Crude protein contents in the range 63 to 65 percent by weight in relation to the dry weight of whole cells can be obtained by cultivating the new strain on the preferred kerosine normal paraflins.
- Production rates of about 5 grams per litre per hour with a minimum of about 2.5 grams per litre per hour can be obtained by the use of the new strain.
- the strain has a high yield factor of about 1, i.e. ratio of the weight of yeast produced in relation to the weight of hydrocarbon utilised by the yeast. It has a high growth rate, particularly on the preferred hydrocarbons, thus permitting operation -at relatively high dilution rates, for example growth rates (division times) of less than 4 hours giving a D max. of more than O.15h It can be cultivated at commercially acceptable growth rates and yield factors under non aseptic conditions in the presence of bacterial contamination.
- yield factor is a measure of the efliciency with which the assimilable hydrocarbons are converted into cellular materials.
- the process can be carried out using any of the known cultivation techniques.
- Preferred temperature ranges are from 27 to 33 C. and preferred pH ranges are 4.0 to 5.5.
- Most suitably cultivation is caried out in a stirred, aerated pressure vessel. Where over pressure is applied it can be in the range up to 5 kilograms per square centimeter absolute.
- high growth rates can be maintained over a wide range of temperature and pH, such as for example a pH range of 3 to 5.7 and a temperature range of 20 to 35 C. This facilitates, in non aseptic operation, the selection of conditions of pH and temperature which cause wash-out of microbial contamination or at least suppresses the contaminant to levels which do not substantially affect the production of yeast biomass.
- bacterial contamination can be suppressed by operation at a pH in the range 4 to 4.8 and conveniently the temperature can be in the range of about 27 to 33 C.
- the new strain is a mutant derived from a wild yeast which we have isolated and identified as Candida lipolytica in accordance with the taxonomic criteria of Lodder.
- the new strain is lodged at the Centraalbureau Voor Schimmelcultures, Baarn, Holland, where it has the C.B.S. number 6331.
- the new strain has the following characteristics.
- Candida lipolytica C.B.S. strain number 2078 and C.M.I. strain 93743 These characteristics correspond with standard description of C. lipolytica var. lipolytica given by J. Lodder, The Yeasts. A Taxonomic Study. 2 ed. 1970 pp. 991-993, except that when plated on glucose/yeast extract/peptone agar or Dalmau plate cultures on corn meal agar (Lodder 2 ed. 1970 p. 992), the colonies are cream coloured, smooth, have a matt surface with no folding and no pseudomycelium is formed.
- Candida lipolytica strain C.B.S. Number 6331 was cultivated continuously under aseptic conditions in a stirred, aerated pressure vessel having a working volume of 1800 litres.
- the carbon substrate was a mixture of kerosine range normal parafiins having C to C carbon atoms per molecule obtained by subjecting a petroleum feedstock to molecular sieve treatment.
- the aqueous nutrient medium had the following composition:
- Thiamine hydrochloride220 milligrams. Tap water to 1 litre.
- the broth had a dry cell weight of 23.6 grams per litre.
- the run was continued for 1000 hours. During this period the broth was sampled at intervals of 24 hours and the culture examined for strain variation. The samples were plated on Sabourauds Dextrose Agar (Oxoid) and Malt Exract Agar (Oxoid). (Oxoid is a registered trademark.) The plates were incubated for 3 days at C. The resulting colonies were cream coloured, smooth, with a matt surface and no folding.
- the yeast had a crude protein content in the range 63 to 66 percent by weight in relation to the dry weight of the yeast.
- the cell concentration was about 1.5 grams/litre. Owing to the slow growth rate the start up period was extended until a cell concentration of 16 grams/litre was reached (Le.
- the yield factor was 0.58.
- Candida lipolytica strain C.B.S. 6331 was inoculated into an aqueous nutrient medium and a hydrocarbon as the source of utilisable carbon contained in a stirred, aerated, pressure vessel having a working volume of 55 litres.
- the hydrocarbon was a mixture of gas-oil range normal parafiins having 11 to 18 and mainly 14 to 17 carbon atoms per molecule which was obtained by subjecting a gas oil petroleum feedstock to a molecular sieve treatment.
- the aqueous nutrient media had the following composition:
- the cell density of the yeast (Candida lipolytica strain C.B.S. 6331) was 23.5 grams per litre and the yield factor was 0.99.
- the yeast product had a crude protein content; of 59 percent by weight in relation to the dry weight of the whole cells.
- the pH of the broth was then raised from 4.5 to 4.8 during a period of operation from 520 to 680 hours.
- Bacterial counts carried out on the broth between 800 to 1200 hours of operation were of the order of 10 to 3 10 cells per millilitre.
- the number of Candida lipolytica cells present during the same period were of a similar order to the numbers of bacterial cells.
- the dry cell weight of the yeast was 21.3 grams per litre and the yield factor was 0.96.
- the crude protein content of the yeast was about 59 percent by weight in relation to the dry weight of the Whole cells.
- This example demonstrates satisfactory continuous operation of a fermentation for the production of yeast biomass using the new strain Candida lipolytica strain CBS. 6331 in the presence of a substantial level of bacterial contamination.
- a process for the conversion of a hydrocarbon into a proteinaceous material which comprises continuously cultivating Candida lipolytica strain C.'B.S. number 6331 in the presence of a straight chain hydrocarbon having at least 10 carbon atoms per molecule, an aqueous nutrient medium and a gas containing free oxygen.
Abstract
1. A PROCESS FOR THE CONVERSION OF A HYDROCARBON INTO A PROTEINACEOUS MATERIAL WHICH COMPRISES CONTINUOUSLY CULTIVATING CANDIDA LIPOLYTICA STRAIN C.B.S. NUMBER 6331 ON THE PRESENCE OF A STRAIGHT CHAIN HYDROCARBON HAVING AT LEAST 10 CARBON ATOMS PER MOLECULE, AN AQUEOUS NUTRIENT MEDIUM AND A GAS CONTAINING FREE OXYGEN.
Description
United States Patent 3,846,238 FERMENTATION PROCESS FOR CONVERT- ING HYDROCARBONS TO PROTEINACEOUS MATERIALS Gordon Homer Evans, Kingswood, England, and Jean Lindsay Shennan, Falkirk, Scotland, assignors to The British Petroleum Company Limited, London, England No Drawing. Filed Sept. 15, 1972, Ser. No. 289,228 Claims priority, application Great Britain, Sept. 17, 1971, 43,421/71 Int. CL C12b 1/00 US. Cl. 195-28 R 3 Claims ABSTRACT OF THE DISCLOSURE A process for the production of yeast biomass from a hydrocarbon substrate wherein the new yeast strain, Candida lipolytica strain CBS number 6331 is continuously cultivated in the presence of a straight chain hydrocarbon having at least carbon atoms per molecule, an aqueous nutrient medium and a gas containing free oxygen.
The present invention is concerned with improvements in and relating to a continuous process for converting hydrocarbons to proteinaceous material. In particular the invention relates to a continuous process for the production of single cell protein by cultivating a new yeast strain on a hydrocarbon as the carbon substrate.
In recent years a number of processes have been proposed for the production of single cell protein by cultivating a yeast on a hydrocarbon substrate, in the presence of an aqueous nutrient medium and a gas containing free oxygen. The proposed processes can be either batch or continuous. Many hydrocarbon assimilating strains of yeast have been disclosed as suitable for use in such processes.
We now provide a new strain of yeast which is particularly suitable for use in continuous industrial scale processes of the foregoing type. The new strain remains stable over prolonged periods of continuous cultivation and the yeast produced has a high crude protein content.
Accordingly the present invention is a process for the conversion of a hydrocarbon into a proteinaceous material which comprises continuously cultivating Candida lipolytica strain C.B.S. number 6331 in the presence of a straight chain hydrocarbon having at least 10 carbon atoms per molecule, an aqueous nutrient medium and a gas containing free oxygen.
Preferred hydrocarbons are normal parafiins recovered from petroleum fractions in the kerosine or gas oil boiling ranges. In particular these hydrocarbons are gas oil boiling range normal paraflins containing 11 to 23 and mainly 14 to 21 carbon atoms per molecule and kerosine boiling range normal parafiins containing 10 to 13 carbon atoms per molecule. Straight chain hydrocarbons obtained from petroleum feedstocks by molecular sieve treatment are most suitable.
Crude protein contents in the range 63 to 65 percent by weight in relation to the dry weight of whole cells can be obtained by cultivating the new strain on the preferred kerosine normal paraflins.
Production rates of about 5 grams per litre per hour with a minimum of about 2.5 grams per litre per hour can be obtained by the use of the new strain. The strain has a high yield factor of about 1, i.e. ratio of the weight of yeast produced in relation to the weight of hydrocarbon utilised by the yeast. It has a high growth rate, particularly on the preferred hydrocarbons, thus permitting operation -at relatively high dilution rates, for example growth rates (division times) of less than 4 hours giving a D max. of more than O.15h It can be cultivated at commercially acceptable growth rates and yield factors under non aseptic conditions in the presence of bacterial contamination. When cultivated in a pressure vessel under an elevated over pressure, for example in the range 1.5 to 5.0 kilograms per square centimeter absolute, preferably under aseptic conditions of operation the strain exhibits a marked increase in yield factor. This feature makes a valuable contribution to the overall economics of the process since yield factor is a measure of the efliciency with which the assimilable hydrocarbons are converted into cellular materials.
The process can be carried out using any of the known cultivation techniques. Preferred temperature ranges are from 27 to 33 C. and preferred pH ranges are 4.0 to 5.5. Most suitably cultivation is caried out in a stirred, aerated pressure vessel. Where over pressure is applied it can be in the range up to 5 kilograms per square centimeter absolute. It is a further feature of the new strain that high growth rates can be maintained over a wide range of temperature and pH, such as for example a pH range of 3 to 5.7 and a temperature range of 20 to 35 C. This facilitates, in non aseptic operation, the selection of conditions of pH and temperature which cause wash-out of microbial contamination or at least suppresses the contaminant to levels which do not substantially affect the production of yeast biomass. For example bacterial contamination can be suppressed by operation at a pH in the range 4 to 4.8 and conveniently the temperature can be in the range of about 27 to 33 C.
The new strain is a mutant derived from a wild yeast which we have isolated and identified as Candida lipolytica in accordance with the taxonomic criteria of Lodder. The new strain is lodged at the Centraalbureau Voor Schimmelcultures, Baarn, Holland, where it has the C.B.S. number 6331.
In addition to the features previously described the new strain has the following characteristics.
The morphological characteristics of the new strain are the same as for Candida lipolytica C.B.S. strain number 2078 and C.M.I. strain 93743, These characteristics correspond with standard description of C. lipolytica var. lipolytica given by J. Lodder, The Yeasts. A Taxonomic Study. 2 ed. 1970 pp. 991-993, except that when plated on glucose/yeast extract/peptone agar or Dalmau plate cultures on corn meal agar (Lodder 2 ed. 1970 p. 992), the colonies are cream coloured, smooth, have a matt surface with no folding and no pseudomycelium is formed.
This contrasts with the pseudomycelium formation in the typical strains of Candida lipolytica e.g. C.B.S. Strain 2078 and C.M.I. Strain 93743.
The physiological characteristics are identical with those of the C. lipolytica C.B.S. Strain No. 2078 and C.M.I. strain 93743 previously mentioned.
(a) Morphological observations when cultivated in glucose yeast extract peptone water When cultivated for 3 days at 25 C. in glucose yeast extract peptone water the cells are short ovoid to long ovoid and measure 3 to 6 by 5 to 11 microns. Rarely some elongated cells are observed which measure up to about 20 microns in length. No pellicle is formed.
(b) Ascospore or Ballistospore formation No ascospores or ballistospores are formed when the strain is grown on the standard sporulation media.
(c) Assimilation of nitrate and decomposition of urea The strain does not assimilate potassium nitrate. Urea is decomposed.
(d) Utilisation of sugars The strain will not ferment sugars but the following compounds are assimilated: glucose, ethanol, glycerol, erythritol and succinic acid.
Candida lipolytica strain C.B.S. Number 6331, was cultivated continuously under aseptic conditions in a stirred, aerated pressure vessel having a working volume of 1800 litres. The carbon substrate was a mixture of kerosine range normal parafiins having C to C carbon atoms per molecule obtained by subjecting a petroleum feedstock to molecular sieve treatment. The aqueous nutrient medium had the following composition:
Grams H P 1.594 KCl 0.916 MgSO 7H O 0.521 MnSO 4H 0 0.035 FeSO 7H O 0.052 Z1'1S047H2O CuSO 7H O 436x10 H so, 0.172
Thiamine hydrochloride220 milligrams. Tap water to 1 litre.
After an initial start-up period of about 16 hours during which the culture reached a concentration of 16 grams per litre, continuous operation was commenced at a dilution rate of 0.16 volumes/volume per hour, a temperature of 32 C. and a pH of 5.5. The pH was maintained by addition of ammonia as required. The hydrocarbon was fed at a rate of 10 litres per hour and the aqueous nutrient medium was fed at a rate of 260 litres per hour. The fermentation was aerated at 1.50 volumes/ volume per minute and the pressure inside the fermenter maintained at 2.50 kilograms per square centimeter absolute.
The yield factor was 0.88 (Yield factor=Wt. of yeast product/wt. of hydrocarbon utilized by the yeast produced). The broth had a dry cell weight of 23.6 grams per litre.
The run was continued for 1000 hours. During this period the broth was sampled at intervals of 24 hours and the culture examined for strain variation. The samples were plated on Sabourauds Dextrose Agar (Oxoid) and Malt Exract Agar (Oxoid). (Oxoid is a registered trademark.) The plates were incubated for 3 days at C. The resulting colonies were cream coloured, smooth, with a matt surface and no folding.
Throughout the fermentation no signs of culture variation were observed on plating. No pseudomycelium was observed by microscopic examination.
The crude protein content was assessed at regular intervals by the procedure given in Fertiliser and Feeding Stuffs Regulations. Statutory Instrument No. 218, 1968.
The yeast had a crude protein content in the range 63 to 66 percent by weight in relation to the dry weight of the yeast.
EXPERIMENT By way of comparison a known hydrocarbon utilising strain of Candida lipolytica, namely, C.M.I. number 93743 was subjected to identical conditions of cultivation to those previously described for the new strain C.B.S. number 6331.
At the end of the 16-hour start up period the cell concentration was about 1.5 grams/litre. Owing to the slow growth rate the start up period was extended until a cell concentration of 16 grams/litre was reached (Le.
after about 40 hours). Continuous operation aws commenced at a dilution rate of 0.15 volumes/volume per hour and the culture washed out. It was not possible to achieve steady operation because the growth rate was too slow.
Steady state operation was achieved at a lower dilution rate of 0.07 volumes/volume per hour using an over pressure of 1.5 kilograms per square centimeter absolute. The crude protein content of the yeast product was about 54 percent by weight in relation to the dry weight of the yeast. The plated colonies were cream coloured, wrinkled, hirsute, dull and coarsely folded. Microscopic examination showed abundant pseudomycelium; septate mycelium was also found.
The yield factor was 0.58.
EXAMPLE 2 Candida lipolytica strain C.B.S. 6331 was inoculated into an aqueous nutrient medium and a hydrocarbon as the source of utilisable carbon contained in a stirred, aerated, pressure vessel having a working volume of 55 litres. The hydrocarbon was a mixture of gas-oil range normal parafiins having 11 to 18 and mainly 14 to 17 carbon atoms per molecule which was obtained by subjecting a gas oil petroleum feedstock to a molecular sieve treatment. The aqueous nutrient media had the following composition:
Grams H PO 1.455 K so 0.969 MgSO 7H O 0.470 ZnSO 7H O 0.138 FeSOflHsO 0.047 Mnso,4H o 0.041 (NHQ SQ, 0.500
CuSO 5H O0.413 milligrams. Thiamin HCl203 milligrams. Tap water to 1 litre.
After a period of batch growth, continuous operation was commenced at a dilution rate of 0.14 to 0.15 volumes per volume per hour, a temperature of 32 C. and a pH of 4.5, maintained by ammonia addition as required. The hydrocarbon was fed at a rate of 220.5 ml./h. and the aqueous nutrient medium was fed at a rate of 7.42 litres/ h. The fermentation was mechanically agitated, aerated at 0.75 volumes/volume per minute and the pressure inside the fermenter was maintained at 1.5 kilograms per square centimeter absolute.
About 240 hours after the initial inoculation with the culture yeast, an inoculum containing five bacteria belonging to the genera Acinetobacter, Escherichia, Paracolobactrum and Pseudomonas was added to the fermenter broth. Bacterial counts carried out at intervals over the following one hundred and eighty hours on samples of fermenter broth indicated that the number of viable bacterial cells present varied between 300,000 to 2,500,000 per millilitre of broth.
After operation for from 330 to 402 hours the cell density of the yeast (Candida lipolytica strain C.B.S. 6331) was 23.5 grams per litre and the yield factor was 0.99. The yeast product had a crude protein content; of 59 percent by weight in relation to the dry weight of the whole cells.
The pH of the broth was then raised from 4.5 to 4.8 during a period of operation from 520 to 680 hours. Bacterial counts carried out on the broth between 800 to 1200 hours of operation were of the order of 10 to 3 10 cells per millilitre. The number of Candida lipolytica cells present during the same period were of a similar order to the numbers of bacterial cells.
Between 1122 to 1218 hours of operation the dry cell weight of the yeast was 21.3 grams per litre and the yield factor was 0.96. The crude protein content of the yeast was about 59 percent by weight in relation to the dry weight of the Whole cells.
After 1218 hours of operation the pH was increased further to 5.0 whereupon operation of the fermenter became unsteady, difficult to control and gave a variable yeast factor. At the same time the bacterial count increased until it exceeded the yeast count.
This example demonstrates satisfactory continuous operation of a fermentation for the production of yeast biomass using the new strain Candida lipolytica strain CBS. 6331 in the presence of a substantial level of bacterial contamination.
It also demonstrates that commercial production of yeast biomass is not satisfactory when the fermentation is operated under nonaseptic conditions at pH values of about 5 or higher.
We claim:
1. A process for the conversion of a hydrocarbon into a proteinaceous material which comprises continuously cultivating Candida lipolytica strain C.'B.S. number 6331 in the presence of a straight chain hydrocarbon having at least 10 carbon atoms per molecule, an aqueous nutrient medium and a gas containing free oxygen.
2. A process as claimed in claim 1 wherein cultivation is carried out in a pressure vessel at an over pressure in the range 1.5 to 5.0 kilograms per square centimeter absolute.
3. A process as claimed in claim 1 when carried out under nonaseptic conditions of operation and at a pH in the range of 4 to 4.8.
References Cited UNITED STATES PATENTS 3,522,147 7/1970 Filosa 19528 R A. LOUIS MONACELL, Primary Examiner R. B. PENLAND, Assistant Examiner
Claims (1)
1. A PROCESS FOR THE CONVERSION OF A HYDROCARBON INTO A PROTEINACEOUS MATERIAL WHICH COMPRISES CONTINUOUSLY CULTIVATING CANDIDA LIPOLYTICA STRAIN C.B.S. NUMBER 6331 ON THE PRESENCE OF A STRAIGHT CHAIN HYDROCARBON HAVING AT LEAST 10 CARBON ATOMS PER MOLECULE, AN AQUEOUS NUTRIENT MEDIUM AND A GAS CONTAINING FREE OXYGEN.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB4342171A GB1401277A (en) | 1971-09-17 | 1971-09-17 | Fermentation process for converting hydrocarbons to proteinaceous materials |
Publications (1)
Publication Number | Publication Date |
---|---|
US3846238A true US3846238A (en) | 1974-11-05 |
Family
ID=10428685
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US00289228A Expired - Lifetime US3846238A (en) | 1971-09-17 | 1972-09-15 | Fermentation process for converting hydrocarbons to proteinaceous materials |
Country Status (15)
Country | Link |
---|---|
US (1) | US3846238A (en) |
JP (1) | JPS5533307B2 (en) |
AT (1) | AT315110B (en) |
BE (1) | BE788902A (en) |
BG (1) | BG25657A3 (en) |
CS (1) | CS166819B2 (en) |
DE (1) | DE2245545C3 (en) |
ES (1) | ES407000A1 (en) |
FR (1) | FR2153029B1 (en) |
GB (1) | GB1401277A (en) |
IT (1) | IT965374B (en) |
NL (1) | NL7212529A (en) |
RO (1) | RO62308A (en) |
SU (1) | SU493978A3 (en) |
ZA (1) | ZA726114B (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS57205687A (en) * | 1981-06-10 | 1982-12-16 | Wakamatsu Sangyo Kk | Method of covering ornamental material of glass reinforced frame for door |
-
0
- BE BE788902D patent/BE788902A/en unknown
-
1971
- 1971-09-17 GB GB4342171A patent/GB1401277A/en not_active Expired
-
1972
- 1972-09-07 ZA ZA726114A patent/ZA726114B/en unknown
- 1972-09-12 BG BG7200021368A patent/BG25657A3/en unknown
- 1972-09-14 JP JP9279472A patent/JPS5533307B2/ja not_active Expired
- 1972-09-14 SU SU1829116A patent/SU493978A3/en active
- 1972-09-15 IT IT52777/72A patent/IT965374B/en active
- 1972-09-15 CS CS6338A patent/CS166819B2/cs unknown
- 1972-09-15 FR FR7232780A patent/FR2153029B1/fr not_active Expired
- 1972-09-15 US US00289228A patent/US3846238A/en not_active Expired - Lifetime
- 1972-09-15 NL NL7212529A patent/NL7212529A/xx unknown
- 1972-09-15 AT AT794472A patent/AT315110B/en not_active IP Right Cessation
- 1972-09-16 RO RO72248A patent/RO62308A/ro unknown
- 1972-09-16 ES ES407000A patent/ES407000A1/en not_active Expired
- 1972-09-16 DE DE2245545A patent/DE2245545C3/en not_active Expired
Also Published As
Publication number | Publication date |
---|---|
NL7212529A (en) | 1973-03-20 |
GB1401277A (en) | 1975-07-16 |
SU493978A3 (en) | 1975-11-28 |
FR2153029A1 (en) | 1973-04-27 |
RO62308A (en) | 1977-08-15 |
CS166819B2 (en) | 1976-03-29 |
JPS4836391A (en) | 1973-05-29 |
AT315110B (en) | 1974-05-10 |
BG25657A3 (en) | 1978-11-10 |
IT965374B (en) | 1974-01-31 |
FR2153029B1 (en) | 1975-01-03 |
DE2245545B2 (en) | 1974-02-14 |
ZA726114B (en) | 1974-04-24 |
ES407000A1 (en) | 1976-02-16 |
DE2245545C3 (en) | 1974-09-19 |
JPS5533307B2 (en) | 1980-08-29 |
BE788902A (en) | 1973-03-15 |
DE2245545A1 (en) | 1973-03-29 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
Dworkin et al. | Experiments with some microorganisms which utilize ethane and hydrogen | |
Hermann et al. | Isolation and characterization of butanol-resistant mutants of Clostridium acetobutylicum | |
US4368268A (en) | Direct fermentation of D-xylose to ethanol by a xylose-fermenting yeast mutant | |
US5192673A (en) | Mutant strain of C. acetobutylicum and process for making butanol | |
JPS6364195B2 (en) | ||
EP0066396B1 (en) | Direct fermentation of d-xylose to ethanol by a xylose-fermenting yeast mutant | |
NO850070L (en) | PROCEDURE FOR THE PREPARATION OF ETHANOL FROM XYLOSE SUBSTANCES | |
JP2018529361A (en) | Clostridium begelin key, use thereof, and method for producing butanol | |
US3930947A (en) | Method of producing microbial cells from methane | |
US4567145A (en) | Continuous production of ethanol by use of respiration deficient mutant yeast | |
Davies et al. | Hyphomycetes utilizing natural gas | |
US4720457A (en) | Selective production of ethyl acetate and acetaldehyde by microorganisms | |
US3846238A (en) | Fermentation process for converting hydrocarbons to proteinaceous materials | |
Shifrine et al. | Determination of carbon assimilation patterns of yeasts by replica plating | |
EP0486024B1 (en) | Lactobacillus SP.B001 and method of producing mannitol | |
Du Preez et al. | The effect of acetic acid concentration on the growth and production of gamma-linolenic acid by Mucor circinelloides CBS 203.28 in fed-batch culture | |
US3607652A (en) | Process for the production of d-arabitol | |
Duvnjak et al. | Isolation and study of a strain of Candida tropicalis growing on n-alkanes | |
Maddox | Production of ethanol and n-butanol from hexose/pentose mixtures using consecutive fermentations with Saccharomyces cerevisiae and Clostridium acetobutylicum | |
US3725200A (en) | Process for fermentative production of yeast cells | |
Dooms et al. | Polyol synthesis and taxonomic characters in the genus Moniliella | |
EP0136804B1 (en) | Industrial-scale process for the production of polyols by fermentation of sugars | |
US4910144A (en) | Yeast strain with high power to produce alcohol by fermentation | |
GB1451020A (en) | Process for producing bacterial cells | |
Güvenilir et al. | Production of acetone-butanol-ethanol from corn mash and molasses in batch fermentation |