FR2555602A1 - ENZYME AND COMPOSITION OF ENZYMES DEGRADING PENTOSANES, METHODS OF OBTAINING AND APPLYING SAME - Google Patents

Abstract

THE INVENTION RELATES TO AN ENZYME COMPOSITION PRESENTING A PENTOSANE ACTIVITY, IN PARTICULAR AT HIGH TEMPERATURES, AND ITS PROCESS FOR OBTAINING IT. THE COMPOSITION IS PREPARED BY FERMENTATION OF TALAROMYCES EMERSONII, IN PARTICULAR OF THE STRAIN IMI116815, AND POSSIBLY BY MEANS OF INCREASING THE ACTIVITY OF PENTOSANASE IN RELATION TO OTHER ENZYMATIC ACTIVITIES. APPLICATIONS TO BAKING BREAD, MANUFACTURING STARCH, PRODUCTION OF MIXED SILK FORAGES AND ANIMAL FEEDS, EXTRACTION OF TEA AND COFFEE, ETC.

Description

The present invention relates to a novel process for the biodegradation of

  pentosans, an enzyme useful for this

  end and a process for obtaining a composition

  ing. Pentosans are a class of poly-

  mothers of one or more natural pentoses. They meet

  in various natural sources such as cereals, eg wheat and oats, plants,

  tea and coffee, seaweed, fruits, vegetables,

  vegetables and sorghum, and their presence is undesirable for

  a number of applications from these natural sources.

  Thus, for example, pentosans are found in cereal flours, in which they fix the water, and

  they help harden or stale the bread after cooking.

  In this case, a reduction in the pentosan content of the flour decreases the tendency to cure. In another example, pentosans are found in the coffee and are found in soluble gums extracted together with coffee during the manufacture of granules or instant coffee powder. The reduction of the pentosan content of these materials makes it possible to achieve higher solids contents during extraction and

  significant savings in the manufacturing process.

cation.

  In the description of the British patent

  No. 1,421,127, the applicant describes a production process

  tion of enzymes that degrade $ -glucans from barley and related e1,4 / e-1,3-glucans. The main enzyme obtained is a 0-1, 4 / 0-1,3-glucanase, of particular interest in the treatment of barley, although it is said that O-glucanase, laminarinase, hydroxyethyl cellulase, cellulase and α-amylase may also be present. Microorganisms of

  Penicillium emersonii are used as the source of

  this enzyme, and in particular the strain that was deposited at the Commonwealth Mycological Institute, Kew, Great Britain,

under the number IMI 116815.

  The Applicant is now able to ferment Talaromyces emersonii (initially called Penicillium emersonii) to produce another enzyme, a pentosanase, which catalyzes the degradation of pentosans, especially pentosans from wheat. The class of these enzymes is known in general and various enzymes

  were used, inter alia, in

  in the manufacture of starch, agriculture, brewing, extraction of plant tissues and the manufacture of vegetable coloring matter. However, in many of these applications, high temperatures are commonly used and there is a need for a thermostable pentosanase that retains good activity.

  over a wide range of high temperatures.

  Thus, according to one aspect of the present

  vention, the applicant provides an enzyme that can be obtained by fermentation from a strain of Talaromyces emersonii species, in particular from

  Talaromyces emersonii Stolk, synonymous with Penicillium emer-

  or Stoly IMI 116815, or a mutant thereof, which is capable of catalyzing the degradation of pentosans. It has been discovered that this new enzyme can be obtained in good yield and at a high concentration of

  satisfactory for commercial use.

  According to a particular aspect of the invention, the

  plaintiff provides an enzyme that can be prepared

  Fermented from a strain of T. emersonii species, particularly T. emersonii IMI 116815, or a mutant thereof, which is capable of catalyzing the degradation of xylan. Xylan is a polymer of a

pentose, xylose.

  This new enzyme has been found to be

  most likely, that is, it retains good activity at elevated temperatures, and is, therefore, of particular interest in the degradation of pentosans at high temperatures. For example, in stability measurements made using the enzyme prepared according to the mode

  procedure of Example 1 described below, the enzyme preserves

  50% of its initial activity after heating

  95 C for six minutes at pH 5.0 in the absence of substrate.

  The enzyme also has a temperature-activity relationship

  It has an advantageous activity and exhibits an optimal activity at 87 ± 2 ° C. using an oat husk xylan substrate while retaining 45% of its optimum activity at 950 ° C. This fact is unusual for an enzyme of fungal origin, and clearly differs, for example, from the results obtained with the 0-glucanase indicated above which has a poorly defined optimum at 60-70 C and

  only 40% of its peak activity at 800C.

  Using a crude enzyme preparation obtained

  by the procedure of Example 1 described below, the following characteristics are measured presented by the enzyme according to the invention:

  (a) the pH corresponding to the optimal activity of the new

  the enzyme is 5.0, measured at 50 ° C using oat husk xylan as the pentosan substrate; (b) the temperature corresponding to the optimal activity of the new enzyme is 87 2 C, measured at pH 5.0 using oat husk xylan as the pentosan substrate;

  (c) the presence of xylose, glucose or maltose before

  additionally has no effect on the activity of the

  zyme when subsequently tested at pH 5.0 and 50 C using an oat husk xylan substrate. The enzyme according to the invention can generally

  be prepared by fermenting an inoculum of T. emer-

  sonii, for example T. emersonii IMI 116815 or a mutant thereof, in a nutrient medium suitable for it. However, the applicant has discovered that the amount of naturally occurring pentosanase can be increased compared to

  amount of $ -glucanase produced by an amendment

  propriety of the fermentation medium. A characteristic

  preferred embodiment of the present invention consists of a preparation

  enzyme, and in a process for obtaining this preparation

  ration, obtained directly by fermentation of Talaromyces

  emersonii, preferably T. emersonii IMI 116815, in the

  the level of pentosanase activity relative to the activity of any 0-1,4 / $ - 1,3-glucanase is, because of this modification, higher than that which is

obtained in a classical way.

  Fermentation can be conducted by methods

  well known in the fermentation industry. The

  strain of T. emersonii can be grown under

  aerobic conditions, preferably in submerged culture, with stirring or mixing with air or oxygen. The fermentation medium used must contain a source of assimilable carbon, a source of digestible nitrogen and, if desired, growth-promoting substances as well as

than mineral salts.

  Suitable carbon sources include pentosan rich materials, for example cereals

  such as barley and wheat, soluble solubles of

  or other by-products of distillation of malt or grain, of cellulose, for example of the variety Solka

Floc, or xylan.

  Suitable nitrogen sources include, for example, barley, soluble residues or other by-products of malt or grain distillation, soybean meal, nitrates or ammonium salts such as

  than ammonium dihydrogen phosphate.

  In the case where it is desired to increase the level of pentosanase activity relative to the activity of any O-glucanase, it is desirable to use a carbon or nitrogen source selected from Scotagran ( a mixture of solubles with dried barley grains), ammonium nitrate, fermented bottled distillation syrup syrups, corn pellets (dried corn kernels mixed with soluble materials),

  Curne syrup and soluble corn extract.

  The mineral salts that can be used in the

  fermentation medium may be, for example,

  fats or chlorides of potassium, magnesium or sodium.

  The growth promoting substances that can be used include trace elements such as

  manganese, iron, zinc, copper or phosphorus.

  The fermentation medium contains advantageous

  barley at a concentration in the range of 0.2

  at 3.5% w / v, soluble solubles of

  distilleries or other underproducts of the distillation

  malt or grain in a concentration in the range of 0.4 to 5.5% by weight per volume, and 0.2 to 3.0%

cellulose by weight by volume.

  The growing conditions such as temperature

  The pH, and the fermentation time, are chosen so that the strain employed can accumulate a maximum amount of the desired enzyme. For example, the fermentation is conveniently conducted at a temperature in the range of 35-60 C, preferably 50-54 C, at a pH of 3.5-4.5 and for i to 20 days, preferably

7 to 10 days.

  The crude culture liquid can be used directly for its enzymatic activity, or, if desired, the whole culture broth can be dried and the resulting powder used. If desired, some purification of the pentosanase can be performed, for example by chromatographic techniques, to obtain an enzyme preparation having pentosanase activity.

  increased relative to the activity of any $ -1,4 / 1,3-glucan

  nase, and a method for performing such purification

  as well as the product obtained are additional aspects

of the invention.

  Alternatively, the enzyme, which is exocellular, can be extracted from the fermentation product by, for example, conventional methods. So, for example, a first

  This step normally consists of separating the

  formed, preferably by means of pre-filtration.

  layer, that is to say using a filter having been re-

  covered with a filter aid adjuvant. The resulting filtrate may be directly used or may conveniently be concentrated, preferably under vacuum,

  to obtain the enzyme in the form of a liquid concentrate.

  The liquid concentrate can itself be used as an enzyme source. If desired, liquid concentrates such as sodium chloride, sodium benzoate or metabisulphite can be added to these liquid concentrates.

  which give the enzyme stability to the

  cation, thermostability and / or bacterial stability

  logic. Alternatively, the liquid concentrate can be ab-

  sorbed in a suitable solid material, for example milled wheat or barley, optionally in the presence of a carrier such as sodium carboxymethylcellulose, and the

  resulting wet mass dried to provide a product of

  active zyme. If desired, the liquid concentrate can itself be dried, for example by spray drying, lyophilization or roller drying, to obtain a

dry enzyme composition.

  Unless the extraction is extensive, which for commercial purposes is ordinarily avoided for economic reasons and is not necessary in view of the range of uses to which a more crude composition may apply, the composition will also other

enzymatic activities.

  In the case where a solid enzyme product is desired, it can be obtained from the filtrate or a liquid concentrate thereof, by conventional methods such as addition precipitation, e.g. a

  excess of water-miscible organic solvent such as an alcohol

  cool, for example ethanol, or a ketone, for example acetone. Direct precipitation or

  a precipitation on a support, typical

  such as starch, methyl cellulose

  or sodium carboxymethylcellulose.

  The inoculum of T. emersonii used in the fermentation

  can be achieved, for example, by developing

  gressively a culture on the surface of the body. Of the-

  development to a productive phase fermentation can conveniently be carried out by conducting a vegetative growth stage in the laboratory followed by one or more inoculation steps in

agitated fermentation.

  Thus, in a typical inoculum preparation, the organism is streaked on a nutrient medium.

  solid, for example an agar medium containing a pep-

  tone (eg 0.5% w / v), sodium chloride (eg 0.4% w / v), glycerol (eg 0.75% w / v), molasses ( for example 0.8% w / v), dihydrogen phosphate from

  potassium (for example 0.006% w / v) and sulphate

  magnesium fate (eg 0.005% MgSO4.7H20 in

  weight / volume) having been previously sterilized, for example

  by autoclaving at about 120 ° C for 15 minutes, and allowed to cool. Incubation is preferably conducted at about 37 ° C for about 10 days, after which the spores produced are used to inoculate a

  liquid medium for vegetative growth, sterility

  for example, by autoclaving at about 120 ° C. for 15 minutes, and containing malt extract (eg 3.3% w / v), yeast extract (e.g. % w / v) and ammonium dihydrogenphosphate (e.g. 0.6% w / v). The culture is preferably conducted until there is good mycene development, for example, for about 72 hours.

  45 hours when using about 500 ml of medium.

  The resulting vegetative culture is then

  used to inoculate a first inoculation stage with stirring. The medium suitable at this stage preferably contains the same components as those previously described for the main fermentation medium, and is

  preferably prepared by sterilizing together all

  in the container of the seeding stage, for example by steam injection. A typical environment

  suitable for the seeding stage is "Medium A" de-

  Hereinafter described in Table 1. Using about 40 liters of medium, the culture is preferably carried out at about C for about 76 hours with rotary stirring, for example at 420 rpm, and aeration, for example at 50 liters / minute.

minute of air.

  The seed culture thus obtained can then be used to inoculate a production stage.

  as described above or, if more seed is born

  may be used in seed stages.

  later, identical in nature to the first.

  It is possible to obtain mutants of T. emer-

  intended for use in iron and steel

  by means of conventional methods of improving

  strains, for example by the use of ionizing radiation

  (for example, X and y rays, ultraviolet light,

  violet; or ultraviolet light in the presence of a photosensitizing agent such as 8-methoxypsoralen),

  chemicals (eg nitrous oxide;

  xylamine; pyrimidine base analogs such as -bromo-uracil; acridines; alkylating agents such as ethyl methanesulphonate or mustard gas; hydrogen peroxide; phenols or formaldehyde),

  thermal or genetic techniques (for example,

  combination, transduction, transformation, lysogenization,

  lysogenic conversion and selection techniques for

spontaneous tants).

  The required enzyme activity can be determined

  in the culture liquid or at any point in an operation.

  isolation by means of a simple test designed to

  reduce the reducing sugars released by the action of the enzyme on a pentosan substrate. So, in a test, a

  sample of the enzyme preparation to be measured is

  diluted and is then incubated for 10 minutes with an excess of pentosan xylan at 50 ° C. in an acetate buffer of pH 5.0. The sugar released is dosed as a maltose equivalent by addition of an alkaline salt reagent of 3,5-dinitrosalicylic acid,

  heating for 5 minutes on a boiling water bath,

  rapid chilling with ice water, measuring the absorption of the solution at 540 nm and converting this measurement into a

  equivalent of maltose by reference to a standard curve.

  obtained by preparing standard dilutions of maltose of

  water content and by reacting them with the reaction

  dinitrosalicylic acid under the conditions just described. As used herein, one unit of enzyme releases 1 mg of maltose equivalent per minute

  under test conditions at 50 C and pH 5.0.

  The enzyme according to the invention is useful for

  various objectives for which other

  tosanases. So, for example, it can be used in

  cooking, in order to reduce the natural content of

  wheat flour and thereby improve the conservation

  the qualities of bread. It can be used in the manufacture and hydrolysis of starch, in order to lower

  the pentosan content of cereals and to reduce the

  cosity of starch slurries that would otherwise affect

  detrimental to the efficiency and cost of recovering

  starch and subsequent hydrolysis. It can be used in agriculture to improve the quality

  mixed forages and feed.

  It can be used in brewing, to improve the production and extraction of sugars that can ferment when the burden includes eg wheat or sorghum, and for the prevention or treatment of certain types of disorders. It can be used for the extraction of plant tissues, for example extraction

  tea, coffee and fruit; and to extract algi-

  nates from seaweed; and in the manufacture of natural vegetable coloring materials. For some of these

  applications, the thermostability of the enzyme is particularly

  advantageously with regard to the temperatures at which

are conducted operations.

  According to another aspect of the invention, the

  deresse therefore provides a method of reducing

  the pentosan content of a pentoxide-containing material

  sanes, a method consisting in placing the said

  material with an enzyme of the invention.

  Typical pentosans which can be degraded with the enzyme of the invention include those found in cereals such as wheat and oats; plants such as tea and coffee and extracts thereof; the fruits; the vegetables; algae and sorghum. In one example, the pentosan may be xylan, for example oxo xylan from oatmeal. In a preferred form of setting

  the application containing pentosans containing

grader comes from wheat.

  In another embodiment of the invention,

  the plaintiff provides a method of reducing the

  xylan neur of a material containing xylan, method

  in which the material is brought into contact with a

zyme according to the invention.

  The enzyme or composition according to the invention can be used by employing the methods usually encountered in enzyme technology. Thus, for example, the enzyme may be contacted with an aqueous medium containing the substrate either in suspension, in admixture, or in solution. The reaction temperature may vary depending on the exact nature of the reaction but is generally in the range of 35 ° C, preferably at the upper end of this range, to 90 ° C and higher in some applications. The pH of the reaction mixture can be, for example, in the range of 4.0-6.5, preferably 4.5-5.5, and especially at pH 5.0. If we

  desired, the reaction mixture may contain other enzymes

  my added, for example an-amylase.

  The strain of Talaromyces emersonii that has been used

  is a subculture of that which was deposited at the Commonwealth Institute, Kew, England, under the number IMI 116815 in 1972, before the signing of the Budapest Treaty on the International Recognition of the Deposit of Microorganisms for Formalities of Deliverance

  Patents (Budapest 1977). The applicant has recently

  This strain was deposited with the Depository Bank on November 19, 1984, under Order No. OC 290604 and under the conditions of the Budapest Treaty, and the Applicant considers that these two strains are identical and that

none of them is usable.

  The following examples illustrate the invention.

  All temperatures are in C and all

  percentages are expressed in weight / volume.

Example 1

  Talaromyces emersonii IMI 116815 was cultured at 37 ° C for 10 days on sterilized agar medium in an autoclave and containing 0.5% peptone, 0.4% NaCl, 0.75% glycerol, 0.8% molasses, 0.006% of

KH2PO4 and 0.005% MgSO4.7H2O.

  The spores produced are used for inoculation

  bottles of a sterilized liquid medium by autoclaving and containing 3.3% of malt extract, 2.0%

  of yeast extract and 0.6% of ammonium dihydrogenphosphate

  monium. The flasks were placed on a rotary shaker (210 rpm, eccentricity 4.9 cm) for 3 days at C. The resulting vegetative culture (400 ml) was used to inoculate 40 liters of Medium A (Table 1).

  sterilized by injecting water vapor into a fermenta-

  stainless steel tank with a capacity of 50 liters. The crop is shaken at 420 rpm and aerated at 50 liters /

min for 75 hours at 50 ° C.

  The resulting culture (4.5 liters) was used to inoculate 40 liters of sterilized Medium A (Table 1) by injecting steam into a stainless steel fermenter with a capacity of 50 liters. Culture

  is agitated at 420 rpm and aerated at 50 liters / min

75 hours at 50 C.

  The resulting culture (4.5 liters) was used to inoculate 40 liters of sterilized Medium A by steam injection into a stainless steel fermenter with a capacity of 50 liters. The culture is stirred at 420 rpm and aerated at 50 liters / min for 36 hours at 500C. The resulting culture (16 liters) is used to inoculate 32 liters of medium B (Table 1) sterilized by injection of steam into a steel fermenter

  stainless steel with a capacity of 50 liters.

  The culture is aerated at 50 liters / minute and stirred intermittently at 420 rpm at 50 ° C. for 10 days. Sterile water is added at an average flow rate of

1.5 liters a day.

  A titration of the exocellular fluid gives a

  concentration of the enzyme according to the invention of 36 V / g.

TABLE 1

  Ingredients Medium A (%) Medium B (%) Crushed barley 1.0 3.38 Soluble residue bottoms 2.25- 5.06 "Solka Floc" 2.25 2.53

(NH4) 2H2PO4 0.34 0.77

K2S04 0.12 0.27

  MgSO4.7H2O 0.01 0.11 NaCl 0.11 0.11 MnSO4. 4H20 0.0005 0.001 FeSO4.7H2O 0.004 0.008 ZnSO4. 7H20 0.004 0.008 CuSO4.5H20 0.0005 0.001

H3PO4 0.5 1.02

Water up to 100%

Example 2

  Demonstration of the variation of the pentosanase ratio:

glucanase on fermentation.

  a) Spores are produced as in Example 1 and used to inoculate a seeding stage in

  250 ml flasks containing 40 ml of Stable Medium A

  rilized by autoclaving. The flasks are incubated at 45 C for 72 hours, shaking at 200 rpm. The resulting culture (4 ml) is used to inoculate 40 ml of sterilized Medium B per pass

  autoclaved in 250 ml flasks. After incubation

  at 45 rpm for 12 days, shaking at 200 rpm, the exocellular culture fluid is titrated to determine barley pentosanase (P) and barley $ -glucanase (G) activities, and the P ratio: G. (b) Essentially the same system is used as in (a) above. By removing Solka Floc and incorporating xylan from oat spelled (2.2%), a P: G ratio is obtained.

  71% higher than that obtained in (a).

Example 3

  To demonstrate the pentosanase activity of the

  zyme produced in Example 1, a solution is incubated

  1% pentosane at 50 ° C in pH 5.0 buffer

  presence of the added enzyme (test system) or with ad-

  addition of an equivalent quantity of water (control system).

  The pentosan substrate used is xylan, from

* oat balls.

  Samples of the test system are taken after 10 minutes, 30 minutes and 22.5 hours, cooled rapidly to avoid further reaction and then

  applied in drops on square plates of chromate

  20 cm side thin layer graphite coated with 0.25 mm silica gel. We also apply drops

  of reference sugar solutions and the control system.

  The mobile phase consists of a mixture of n-butanol: pyridine: ethanol: water (20: 15: 25: 10). The detection is carried out by spraying, on the dried plates, 5% ammonium molybdate in 5% sulfuric acid,

  then heating at 105 C for 15 minutes.

  All test samples are presented between

  other, a stain with a value of Rf identical to that pre-

  with the reference sugar solution based on xy-

  lose. Since the control sample gives only a single spot at the origin, this test spot can not come from xylose contamination of the substrate or

  its chemical hydrolysis: it must come from a

enzymatic gradation of pentosan.

Example 4

  The following comparative test is intended to illustrate

  the potential utility of the enzyme according to the invention

  in a process of enzymatic digestion of wheat starch.

  The enzyme (2 ml) prepared is vigorously shaken

  according to Example 1, wheat flour of inferior quality

  (155 g), sodium chloride (2 g), chlorine

  of calcium (0.17 g), bacterial alpha-amylase

  myl "(Novo Industri A / S) (1 ml) and water (250 ml) in a glass vial The pH is adjusted to 6.5 using caustic soda. minimize evaporation and the flask is kept for 5 hours at a temperature of 90 C. Starch hydrolysis occurs (negative result of the iodine test) and the viscosity of the digestion product is of

43 mPa.s.

  In a control experiment in which the enzyme of the invention is omitted, the final viscosity of the product of

digestion is 127 mPa.s.

  The following examples illustrate experiences

  performed to characterize the enzyme according to the invention.

  In each example, the enzyme used is prepared according to the method of Example 1, with the difference that

  small amounts of sodium benzoate and metabis-

  sodium sulphide to the exocellular fluid as a stabilizer

  bacteriological health. The enzymatic activity is deter-

  each example using an excess of 1% aqueous solution of oat bean xylan as a pentosan substrate and measuring the increase of the reducing activity after a 10 minute incubation, with reference

  to a standard curve of xylose. PH and temperature

  Each incubation is indicated in the examples.

Example 5

  The pH-activity relationship is obtained at a temperature of

at 50 C.

  pH 4.0 4.5 5.0 5.5 6.0 6.5% maximum activity 62 85 100 84 70 47 Significant hydrolysis occurs throughout

the illustrated range.

Example 6

  The thermal stability is studied by keeping the samples at 60, 70, 80, 90 and C in the absence of substrate and taking amounts at intervals to obtain a family of residual activity-time curves. The remaining activity is measured at pH 5,0 and 50 ° C: - at 60 ° C, there is no loss of activity after minutes, - at 70 ° C, 70% of the activity remains initial after 1 hour, - at 80 C, there is still 70% of the initial activity after 30 minutes, - at 90 C, there is still 50% of the initial activity after 8 minutes, - at 95 C, it remains still 50% of initial activity

after 6 minutes.

Example 7

  The temperature-activity relationship is obtained at a pH of 5.0. An examination of the activity-temperature curve

  reveals that peak activity occurs at 87 2 C.

  Activities at individual temperatures studied,

  expressed in percentages of this maximum, are the following

your:

15 ...

  % of activity 13 24 41 57 86 [100] 90 45 maximum Temperature C 40 50 60 70 80 [87 2] 90 95 The results confirm thermal stability

  inherent to the new enzyme, as shown in the example

  5. The enzyme can clearly be used at times

temperatures above 90 C.

  This is distinguished from a poorly defined optimum.

  or 60-700 C for the barley 6-glucanase of the patent

  tannic acid 1,421,127. At 80 ° C, only 40% of

peak activity.

Example 8.

  In a preliminary study to determine whether the activity of the enzyme is affected by the reaction products and / or other sugars present in a representative digestion product in an industrial process, the enzyme is separately added to the enzyme. simple sugars (xylose,

  glucose and maltose) which is then titrated at 50 ° C. and pH 5.0.

  Each of the sugars is added in an amount equivalent to

  the amount of xylose released by the substrate into the

of the analysis.

  There is no inhibition or enhancement of enzymatic activity and thus, obviously, the enzymatic activity is not affected by the accumulation of simple sugars as occurs in many cases. many

industrial applications.

Claims (14)

  1. Enzyme, characterized in that it can be   obtained from a strain of the species Talaromyces emer-   sonii or a mutant thereof, and who is capable of   talyser the degradation of pentosans. 2. Enzyme according to claim 1, characterized in that it has a pH of optimum activity, measured at C, of about 5.0, and an optimum activity temperature, measured at pH 5.0, of 87. 2 C, and in that it retains about 50% of its initial activity after heating at C for six minutes at pH 5.0, all measurements being made using a pentosan substrate consisting of xylan oat balls.   An enzyme composition, characterized in that it comprises an enzyme according to claim 1 or 2 in admixture with a 1,4-1,4-glucanase and in which the level of pentosanase activity has been increased relative to the level of activity of 0-1,4 / B-1,3-glucanase by modification of the fermentation medium in which each is produced.   4. Enzyme or composition according to any one of   Claims 1 to 3, characterized in that the strain   used is Talaromyces emersonii IMI 116815, CiI CC 290604 or a mutant thereof.   5. Process for preparing a composition of   zyme having pentosanase activity, characterized   in that it comprises the fermentation of a microbial strain   organisms of the species Talaromyces emersonii in a nutrient medium suitable for him, by which is produced a broth containing said enzyme.   6. Method according to claim 5, characterized   in that the level of pentosanase activity is increased   compared to the activity level of 0-1,4 / 0-1,3-   glucanase by modification of the nutrient medium.   7. Process according to claim 5 or 6,   in that the level of pentosanase activity is   increased relative to the level of activity of $ -1.4 / 0-1.3-   glucanase by a purification step subsequent to the fermentation.   8. Process according to any one of the claims   5 to 7, characterized in that the strain is Talaromyces   emersonii IMI 116815, MIC CC 290604 or a mutant thereof.   9. Process for reducing the pentosan content of a pentosan-containing material, characterized in that it consists in bringing said material into contact with an enzyme or a composition according to any one of the following: Claims 1 to 4.   10. Process according to claim 9, characterized   in that the pentosan-containing material is a   selected from wheat and oats, a plant selected from tea and coffee or an extract thereof, a fruit or a vegetable.   11. The method of claim 9 or 10,   characterized in that the pentosan-containing material is the starch.   12. A method according to claim 9 or 10,   characterized in that the pentosan-containing material is wheat or wheat.   13. Process according to any one of the claims   9 to 12, characterized in that the enzyme is contacted with the pentosan-containing material in an aqueous medium at a temperature in the range of   -95 C and at a pH in the range of 4.0 to 6.5.   14. Use of a composition containing a   enzyme of the pentosanase type from a strain of   species Talaromyces emersonii in the reduction of the   in pentosans of a cereal selected from wheat and wheat.   of a plant selected from tea and coffee or an ex-   trait of these, a fruit or a vegetable.