Pediococcus acidilactici for producing lactic acid by using xylose and application thereof

Abstract

The invention belongs to the technical field of fermentation, and particularly relates to pediococcus acidilactici capable of efficiently utilizing xylose to produce lactic acid and application of the pediococcus acidilactici. The xylose metabolism capability of the pediococcus acidilactici JDYJY4.1805-2401 provided by the invention is greatly improved compared with that of an initial strain, and xylose in a culture medium can be fully utilized to grow, metabolize and produce lactic acid; the high-light pure lactic acid can be produced by efficiently utilizing the lignocellulose hydrolysate through fermentation, and a technical guarantee is provided for large-scale production of lactic acid from straw sugar. 46.2 g / L of lactic acid can be obtained by fermenting pediococcus acidilactici JDYJY 4.1805-2401 with 50g / L of xylose, and the conversion rate of the lactic acid to the xylose is greater than 90%; the corn straw and miscanthus sinensis straw enzymolysis mixed liquor (containing 109.1 g / L of glucose and 50.9 g / L of xylose) is used for fermentation, the fermentation period is 36-42 h, the acid yield can reach 142 g / L, the residual sugar in the fermentation liquor is 0.45%-1%, and the lactic acid light purity is 98.0%-99.92%.

Description

Technical Field

[0001] The invention belongs to the technical field of fermentation, and particularly relates to Pediococcus acidilactici that efficiently utilizes xylose to produce lactic acid and application thereof. Background Art

[0002] Lactic acid is an important industrial chemical, which is widely used in food, medicine, leather and textile industries. The existing reports on the production of L-lactic acid include: Lactobacillus ( Lactobacillus ) Rhizopus oryzae )、Bacillus( Bacillus subtilis ), Escherichia coli ( Escherichia coli ), Saccharomyces cerevisiae, Corynebacterium glutamicum, etc. 90% of the world's commercial L-lactic acid is obtained by biofermentation of corn starch raw materials using the above strains. The cost of corn starch raw materials accounts for about 70% of the total fermentation cost. Therefore, it is urgent to find a cheap raw material to replace starch raw materials for L-lactic acid production.

[0003] The use of plant fiber raw materials, which is a widely available and low-cost renewable energy source, to ferment and produce lactic acid can reduce the production cost of lactic acid and alleviate the food shortage situation. This has become a research focus. After various treatments, lignocellulose can be used to obtain a hydrolyzate with sufficient carbon source (mainly composed of glucose and xylose). Glucose, as a basic carbon source, can be used by most microorganisms, but there are very few natural microorganisms that can effectively use xylose and metabolize it efficiently into economical and applicable products.

[0004] In order to fully utilize the carbon source in the acid hydrolyzate or enzyme hydrolyzate of lignocellulose, microorganisms must be able to efficiently utilize not only glucose but also xylose. At present, there are not many strains of natural microorganisms that can effectively metabolize xylose into lactic acid. Laboratories usually use modified Pediococcus acidilactici, Lactobacillus plantarum, and recombinant Escherichia coli for fermentation experiments.

[0005] According to reports Enterococcus casseliflavus 38 g / L lactic acid was obtained by fermentation of 50 g / L xylose, the conversion rate of lactic acid to xylose was 76%, and the purity of lactic acid was 86%. Lactobacillus pentosus CHCC2355 and L.brevis CHCC2097 fermented 2% xylose with a conversion rate of no more than 60%; Lactococcus lacticus Although the sugar-acid conversion rate was greatly improved when xylose exceeded 50 g / L after the introduction of the pentose phosphate pathway / glycolysis pathway, about 1 / 4 of the xylose was metabolized to acetic acid due to its own growth needs. E.coli B knocked out the pyruvate formate lyase gene (pfl) and the D-lactate dehydrogenase gene ( ldhA ) after inserting Streptococcus bovis of ldhL Gene, succinic acid is produced in the fermentation product, and the conversion rate of xylose to lactic acid is 78%. The above research shows that the existing various strains of bacteria use xylose to produce lactic acid but have problems such as low lactic acid purity and low sugar-acid conversion rate. Summary of the invention

[0006] Pediococcus acidilactici is a strain that can naturally utilize xylose, but the xylose utilization efficiency of wild Pediococcus acidilactici is very low. In order to solve the above technical problems, the applicant separated and purified the Pediococcus acidilactici strain from the corn syrup stored for a long time, and used it as the starting strain to verify the performance in the culture medium with xylose as the carbon source. After confirming that it has a certain ability to metabolize xylose, it was repeatedly screened and purified by xylose shake flask and plate, and directional artificial selection was carried out with the goal of improving the conversion rate of L-lactic acid, and a strain with stable growth metabolism and high conversion rate of L-lactic acid in xylose culture medium was obtained. The strain was named JDYJY4.1805-2401. The strain can use single xylose as a carbon source to ferment and produce lactic acid, and the xylose conversion rate is greater than 90%. At the same time, it can also use corn stalks and Miscanthus straw enzymatic hydrolysis mixed liquid as a carbon source to ferment and produce lactic acid, and the optical purity of the produced lactic acid can reach 99.92%.

[0007] One of the technical solutions provided by the present invention is a strain of Pediococcus acidilactici that can utilize xylose to produce lactic acid, wherein the Pediococcus acidilactici is specifically Pediococcus acidilactici ( Pediococcus acidilactici ) JDYJY 4.1805-2401, the strain was deposited in the General Microbiology Center of China Microbiological Culture Collection Administration on January 16, 2024, the deposit address is: No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing, Institute of Microbiology, Chinese Academy of Sciences, Postal Code 100101, Deposit Number CGMCCNo.29632.

[0008] The second technical solution provided by the present invention is the lactic acid bacteria ( Pediococcus lactic acid ) Application of JDYJY 4.1805-2401, in particular in the production of lactic acid, more particularly in the production of lactic acid using xylose as a carbon source; Furthermore, the Pediococcus acidilactici ( Pediococcus acidilactici ) JDYJY 4.1805-2401 can use xylose as the sole carbon source for lactic acid production; Furthermore, the Pediococcus acidilactici ( Pediococcus acidilactici ) JDYJY 4.1805-2401 can also use lignocellulose hydrolysate containing xylose as a carbon source for lactic acid production; Furthermore, the source of the lignocellulose includes but is not limited to: at least one of Miscanthus, corn cobs, straw, etc.; the straw includes but is not limited to: at least one of corn straw, wheat straw, rice straw, etc.

[0009] The third technical solution provided by the present invention is the lactic acid bacteria ( Pediococcus lactic acid ) JDYJY 4.1805-2401 A method for producing lactic acid by fermentation; Inoculate JDYJY 4.1805-2401 seed liquid into the fermentation medium at an inoculum rate of 10% to 20%, and ferment at 100 to 150 rpm for 16 to 110 hours at 40 to 50°C and pH 4.7 to 6.8; Preferably, the fermentation time in the fermentation tank is 31-42h; Preferably, the fermentation temperature is 45°C to 48°C; Preferably, the pH during the fermentation process is controlled to be 5.4-6.3; Preferably, a pH neutralizer is used to regulate the pH value during the lactic acid fermentation process, and the pH neutralizer used includes but is not limited to one or more of calcium hydroxide, sodium bicarbonate, sodium carbonate, ammonia water, and calcium carbonate; Furthermore, the fermentation medium uses xylose as the sole carbon source and specifically includes the following components: 40-150 g / L xylose, 3-40 g / L yeast powder, 10-60 g / L peptone, 5-60 g / L sodium acetate, 2-30 g / L triammonium citrate, 0.5-2 g / L dipotassium hydrogen phosphate, 0.5-2 g / L potassium dihydrogen phosphate, 0.3-1 g / L manganese sulfate, 0.3-1 g / L ferrous sulfate, and the rest is water; Preferably, the fermentation medium uses xylose as the sole carbon source, and is specifically composed of: 50-120 g / L xylose, 5-30 g / L yeast powder, 15-50 g / L peptone, 10-40 g / L sodium acetate, 4-25 g / L triammine citrate, 1-1.5 g / L dipotassium hydrogen phosphate, 1-1.5 g / L potassium dihydrogen phosphate, 0.5-1 g / L manganese sulfate, 0.5-1 g / L ferrous sulfate, and the rest is water; Furthermore, the carbon source of the fermentation medium is lignocellulose hydrolyzate; the source of the lignocellulose includes but is not limited to: at least one of Miscanthus, corn cobs, straw, etc.; the straw includes but is not limited to: at least one of corn straw, wheat straw, rice straw, etc.

[0010] Furthermore, the method for preparing the lignocellulose hydrolysate comprises the steps of pre-treating the raw materials, detoxifying, and enzymolyzing; Furthermore, the pretreatment is to crush the raw material to obtain a powdery material with a discharge fineness of less than 3 mm; Furthermore, the detoxification is to deconstruct the powdered material using a high-temperature dilute alkali solution and a dilute acid solution to remove lignin and hemicellulose; further, the dilute alkali solution is a 2%-5% (w / v) sodium hydroxide solution; the dilute acid solution is a 2%-5% (w / v) dilute sulfuric acid; Furthermore, the enzymatic hydrolysis is to use cellulase to enzymatically hydrolyze the detoxified raw material to obtain a lignocellulose enzymatic hydrolysis mixed solution; Furthermore, the preparation method of the lignocellulose hydrolyzate is as follows: The raw material is crushed to obtain a powder material with a discharge fineness of less than 3 mm; the powder material is soaked in a dilute alkali solution of 2%-5% by mass (preferably 3%) at 80°C, with a solid-liquid ratio of 1:10 and a treatment time of 2 hours to remove lignin, and then washed with water to neutrality; the material is washed with water using 2%-5% dilute sulfuric acid (preferably 2.5%) for a treatment time of 1.5 hours to remove hemicellulose, and then washed with water to neutrality; the supernatant is filtered to remove, and after drying the precipitate, deionized water is added to obtain a suspension, and cellulase is added to the suspension at an amount of 1500-3000U / ml, and the neutral material after detoxification (removing lignin and hemicellulose) is enzymatically hydrolyzed at a temperature of 55-60°C (preferably 58°C) and a hydrolysis time of 46-54 hours (preferably 50 hours) to obtain a lignocellulose hydrolyzate.

[0011] Beneficial effects: The lactic acid Pediococcus JDYJY4.1805-2401 provided by the present invention is cultured under optimal conditions, and its xylose metabolism ability is greatly improved compared with the initial strain, and it can fully utilize the xylose growth metabolism and lactic acid output in the culture medium, and can efficiently utilize the corn stalks and Miscanthus straw enzymatic hydrolysis mixed liquid to ferment and produce high-purity lactic acid, providing technical guarantee for the large-scale production of lactic acid from straw sugar. Lactic acid Pediococcus JDYJY 4.1805-2401 can obtain 46.2g / L lactic acid by fermenting 50g / L xylose, and the conversion rate of lactic acid to xylose is greater than 90%; using corn stalks and Miscanthus straw enzymatic hydrolysis mixed liquid for fermentation (containing 109.1g / L glucose and 50.9g / L xylose), the fermentation cycle is 36-42h, the acid production can reach 142g / L, the residual sugar in the fermentation liquid is 0.45%-1%, and the lactic acid optical purity is 98.0%-99.92%. DETAILED DESCRIPTION

[0012] In order to make the purpose, technical solution and advantages of this patent more clear, this patent is further described in detail in combination with specific embodiments. It should be understood that the specific embodiments described here are only used to explain this patent and are not used to limit the present invention.

[0013] The lactic acid bacteria disclosed in the present invention ( Pediococcus acidilactici ) JDYJY 4.1805-2401, the strain was deposited in the General Microbiology Center of China Microbiological Culture Collection Administration on January 16, 2024, the deposit address is: No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing, Institute of Microbiology, Chinese Academy of Sciences, Postal Code 100101, Deposit Number CGMCC No.29632.

[0014] The present invention will be further explained below in conjunction with specific embodiments.

[0015] Example 1: Verification, isolation and optimization of Pediococcus acidilactici that efficiently utilizes xylose After isolating and purifying the lactic acid Pediococcus strain from long-term stored corn syrup, a wild-type original strain was obtained. The wild-type strain was able to grow and metabolize under the condition of mixed carbon source of glucose and xylose. When cultured under the condition of single carbon source xylose, it tolerated xylose concentration of 1%-3%. After culturing for 24 hours under the condition of 3% xylose concentration, OD 620 The pH value of the strain was 0.19-0.33 (tenfold dilution), and the L-lactic acid yield was 6-15g / L. This was used as the starting strain, and the performance was verified in xylose medium. After confirming that it had a certain ability to metabolize xylose, it was screened and purified. At the same time, directional artificial selection was carried out with the goal of improving the L-lactic acid conversion rate. A strain that grew and metabolized in xylose medium and had a high L-lactic acid conversion rate was obtained. The strain was named JDYJY 4.1805-2401 and stored in a glycerol tube. The strain was also deposited in the General Microbiological Center of the China Microbiological Culture Collection Administration, with the deposit number CGMCC No.29632.

[0016] Example 2: Concentration gradient verification of single carbon source (xylose) utilization capacity Take the lactic acid Pediococcus JDYJY 4.1805-2401 and wild-type original strains stored in glycerol tubes, pick a ring with an inoculation needle, streak on the solid plate of seed culture medium, and culture at 45℃ for 36h. Pick a single colony on the plate, expand it on the slant, and wash the slant with 100ml liquid seed culture medium into a 250ml triangular flask as the seed solution for subsequent experiments.

[0017] Set the culture medium with 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, and 10% xylose as the single carbon source, and perform shake flask fermentation at 10% inoculation, 45°C, and 120 r / min until the carbon source is exhausted: After culturing for different time periods, the bacterial concentration (ten-fold dilution) and L-lactic acid production of Pediococcus acidilactici JDYJY 4.1805-2401 and the wild-type original strain are shown in the following table.

[0018] The results show that in 10% xylose medium, JDYJY 4.1805-2401 strain grows normally, OD 620 Reaching 0.5 (ten-fold dilution), it can be seen that strain JDYJY 4.1805-2401 can tolerate 10% xylose concentration, and at this concentration, the lactic acid production is not significantly different from that of glucose as the only carbon source (other components except the carbon source are the same, only xylose is replaced by an equal amount of glucose), and the lactic acid production reaches 69g / L. The wild-type original strain can only tolerate 3% xylose, and the L-lactic acid production is also much lower than JDYJY 4.1805-2401.

[0019]

[0020] Seed culture medium composition: xylose 10 g / L, yeast powder 10 g / L, peptone 15 g / L, sodium acetate 20 g / L, triammonium citrate 15 g / L, dipotassium hydrogen phosphate 1 g / L, potassium dihydrogen phosphate 1 g / L, manganese sulfate 0.8 g / L, ferrous sulfate 0.8 g / L, and the rest is water.

[0021] The culture medium with xylose as the single carbon source consists of: 1-10% xylose, 8 g / L yeast powder, 10 g / L peptone, 20 g / L sodium acetate, 15 g / L triammonium citrate, 1 g / L dipotassium hydrogen phosphate, 1 g / L potassium dihydrogen phosphate, 0.8 g / L manganese sulfate, 0.8 g / L ferrous sulfate, and the rest is water, with an initial pH of 5.8-6.5.

[0022] Example 3: Performance verification of strains under fermentation tank conditions Take a ring of Pediococcus acidilactici JDYJY 4.1805-2401 stored in a glycerol tube, use an inoculation needle to pick up a circle, streak on a solid plate of seed culture medium, and culture at 45℃ for 36h. Pick a single colony on the plate, expand it on a slant, wash the slant with 100ml liquid seed culture medium and place it in a 250ml Erlenmeyer flask, culture it at 45℃ and 120r / min for 12h, and use it as seed liquid.

[0023] Fermentation tank culture: Using 5% xylose as the initial sugar concentration, 10% inoculation was inoculated into a 5L fermentation tank containing 2.4L fermentation medium, and the maturity verification was carried out at 45°C and 100r / min. During the fermentation process, 20% (w / v) calcium hydroxide was used to adjust the pH value to between 5.4 and 6.1.

[0024] After 31 hours of fermentation, the carbon source was exhausted. After 35 hours of fermentation, lactic acid was extracted from the fermentation broth, and the L-lactic acid yield and optical purity were determined. The test results showed that the optical purity reached 99.92%, the L-lactic acid yield was 46.2 g / L, and the sugar-acid conversion rate was 92.4%. Seed culture medium composition: xylose 10 g / L, yeast powder 10 g / L, peptone 15 g / L, sodium acetate 20 g / L, triammonium citrate 15 g / L, dipotassium hydrogen phosphate 1 g / L, potassium dihydrogen phosphate 1 g / L, manganese sulfate 0.8 g / L, ferrous sulfate 0.8 g / L, and the rest is water.

[0025] Fermentation medium composition: xylose 50 g / L, yeast powder 8 g / L, peptone 10 g / L, sodium acetate 20 g / L, triammonium citrate 15 g / L, dipotassium hydrogen phosphate 1 g / L, potassium dihydrogen phosphate 1 g / L, manganese sulfate 0.8 g / L, ferrous sulfate 0.8 g / L, and the rest is water.

[0026] Example 4 Acid resistance verification Take a ring of Pediococcus acidilactici JDYJY 4.1805-2401 stored in a glycerol tube, use an inoculation needle to pick up a ring, streak it on a solid plate of seed culture medium, and culture it at 45℃ for 36h. Pick a single colony on the plate, expand it on a slant, and use 100ml liquid seed culture medium to wash the slant bacterial lawn into a 250ml triangular flask as the seed solution for subsequent experiments; Set the fermentation medium with initial pH value of 4.6, 4.7, 4.8, 4.9, 5.0, 5.1, 5.2, 5.3, 5.4, 5.5, 5.6, 5.7, 5.8, 5.9, 6.0, use 50g / L xylose as the sole carbon source, and perform shake flask fermentation at 10% inoculation, 45℃, and 120r / min for 48h: After 48 h of cultivation, the strain grew normally in the medium with an initial pH value above 5.0, and the OD 620 Reached 0.4-0.7 (ten-fold dilution); the initial pH value was 4.6-4.9, the strain was able to grow, the OD value of the fermentation liquid increased from 0.08 (ten-fold dilution) of the wild-type original strain to 0.28 (ten-fold dilution), and the acid production reached 16g / L, proving that strain JDYJY 4.1805-2401 can tolerate a pH value of 4.6.

[0027]

[0028] Fermentation medium composition: xylose 50 g / L, yeast powder 10 g / L, peptone 15 g / L, sodium acetate 20 g / L, triammonium citrate 15 g / L, dipotassium hydrogen phosphate 1 g / L, potassium dihydrogen phosphate 1 g / L, manganese sulfate 0.8 g / L, ferrous sulfate 0.8 g / L.

[0029] Example 5: Tank verification using corn straw and Miscanthus straw enzymatic hydrolyzate mixture as carbon source A batch of tank experiments were carried out based on the use of corn straw and Miscanthus straw enzymatic hydrolyzed mixed solution (containing 109.1 g / L glucose and 50.9 g / L xylose) to replace the xylose carbon source in the fermentation medium of Example 3: (1) Pick a ring of Pediococcus acidilactici JDYJY 4.1805-2401 stored in a glycerol tube with an inoculation needle, streak it on a solid plate of seed culture medium, and culture it at 45°C for 36 hours. Pick a single colony on the plate, expand it on a slant, wash the slant with 100ml of liquid seed culture medium and place it in a 250ml conical flask, culture it at 45°C and 120r / min for 12 hours, and use it as seed liquid for later use; the seed culture medium is the same as that in Example 3; (2) Maturation verification was carried out in a four-tank fermenter (5 L). The seed liquid was inoculated into the fermentation medium at an inoculation rate of 10% (v / v) and the fermentation was carried out at 45°C and 100 r / min. During the fermentation process, 20% (w / v) calcium hydroxide was used to adjust the pH value to between 5.4 and 6.1.

[0030] (3) The fermentation liquid was sampled on time to test the cell density and sugar and acid content. The test results showed that the fermentation cycle was 42 hours and the final L-lactic acid production was 142 g / L. The residual sugar in the fermentation liquid was measured and lactic acid was extracted. The test results showed that the residual sugar in the fermentation liquid was 0.45% and the optical purity was 99.92%, indicating that the strain can make good use of the carbon source in the straw enzymatic hydrolysate and produce high-optical purity lactic acid.

[0031] The preparation method of the enzymatic hydrolysis mixture of corn straw and Miscanthus straw is as follows: The corn stalks and the silver grass stalks were crushed to obtain a powder material with a discharge fineness of less than 3 mm (mixed at a mass ratio of 3:2); the powder material was soaked in a 3% sodium hydroxide solution at 80°C, with a solid-liquid ratio of 1:10 and a treatment time of 2 hours to remove lignin, and then washed to neutrality; the material was washed with 2.5% dilute sulfuric acid (solid-liquid ratio of 1:5) for a treatment time of 1.5 hours to remove hemicellulose, and then washed to neutrality; the supernatant was filtered and removed, and the precipitate was dried and mixed with deionized water at a ratio of 1:20 to obtain a suspension, cellulase was added to the suspension at an amount of 2500U / ml, and the neutral material after detoxification (removing lignin and hemicellulose) was enzymatically hydrolyzed with cellulase at a temperature of 58°C and a hydrolysis time of 50 hours to obtain a lignocellulose enzymatic hydrolysis mixture containing 109.1g / L glucose and 50.9g / L xylose.

[0032] The preparation method of the fermentation medium is as follows: in the above-prepared lignocellulose enzymatic hydrolysis mixture containing 109.1 g / L glucose and 50.9 g / L xylose, 8 g / L yeast powder, 10 g / L peptone, 20 g / L sodium acetate, 15 g / L triammine citrate, 1 g / L dipotassium hydrogen phosphate, 1 g / L potassium dihydrogen phosphate, 0.8 g / L manganese sulfate, and 0.8 g / L ferrous sulfate are added to obtain a fermentation medium.

[0033] The nutrient elements are dissolved in a small amount of deionized water and sterilized separately from the enzymatic solution at a temperature of 115°C for 20 minutes. The mixture of the two after sterilization is the fermentation medium.

[0034] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent. It should be pointed out that, for ordinary technicians in this field, the above-mentioned implementation methods can also be modified, combined and improved without departing from the concept of this patent, which all belong to the protection scope of this patent. Therefore, the protection scope of this patent shall be based on the claims.

Claims

1. A strain of Pediococcus acidilactici, wherein the Pediococcus acidilactici is specifically Pediococcus acidilactici ( Pediococcus acidilactici ) JDYJY 4.1805-2401, accession number CGMCC No.29632.

2. Use of the Pediococcus acidilactici according to claim 1 in producing lactic acid.

3. The use according to claim 2, characterized in that It is used in the production of lactic acid using xylose as the sole carbon source.

4. The use according to claim 2, characterized in that It is the application in the production of lactic acid using lignocellulose hydrolysate as a carbon source.

5. The use according to claim 4, characterized in that The source of the lignocellulose includes, but is not limited to, at least one of miscanthus, corn cobs, straw, etc.; the straw includes, but is not limited to, at least one of corn straw, wheat straw, rice straw, etc.

6. The use according to claim 2, characterized in that Using Pediococcus acidilactici ( Pediococcus acidilactici ) JDYJY 4.1805-2401 The method for producing lactic acid by fermentation is as follows: The seed liquid of JDYJY 4.1805-2401 was inoculated into the fermentation medium at an inoculation rate of 10%-20%, and fermented at 100-150 rpm for 16-110 h at 40°C-50°C and pH 4.7-6.

8.

7. The use according to claim 6, characterized in that The fermentation medium uses xylose as the sole carbon source and specifically includes the following components: 40-150 g / L of xylose, 3-40 g / L of yeast powder, 10-60 g / L of peptone, 5-60 g / L of sodium acetate, 2-30 g / L of triammonium citrate, 0.5-2 g / L of dipotassium hydrogen phosphate, 0.5-2 g / L of potassium dihydrogen phosphate, 0.3-1 g / L of manganese sulfate, 0.3-1 g / L of ferrous sulfate, and the rest is water.

8. The use according to claim 6, characterized in that The carbon source of the fermentation medium is lignocellulose hydrolyzate; the source of the lignocellulose includes but is not limited to: at least one of Miscanthus, corn cobs, straw, etc.; the straw includes but is not limited to: at least one of corn straw, wheat straw, rice straw, etc.

9. The use according to claim 8, characterized in that The lignocellulose hydrolysate is obtained by performing the steps of crushing pretreatment, detoxification and enzymatic hydrolysis on the raw materials.

10. The use according to claim 9, characterized in that The pretreatment is to crush the raw materials to obtain powdery materials with a discharge fineness of less than 3 mm; The detoxification process is to use high-temperature dilute alkali solution and dilute acid solution to deconstruct the powdered material and remove lignin and hemicellulose; the dilute alkali solution is 2%-5% sodium hydroxide solution; the dilute acid solution is 2%-5% dilute sulfuric acid; The enzymatic hydrolysis is to use cellulase to enzymatically hydrolyze the detoxified raw materials to obtain a lignocellulose enzymatic hydrolysis mixed solution.

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