52 results about "Cellulose hydrolysis" patented technology

The invention belongs to the technical field of biology, and particularly relates to a method for producing xylitol through two-step enzyme catalysis of hemicellulose hydrolysate, and the method comprises the following steps: taking hemicellulose hydrolysate as a raw material, adding arabinose dehydrogenase, NADH oxidase and coenzyme NADH, and carrying out first-step fermentation until no L-arabinose residue exists in fermentation liquor to obtain fermentation reaction liquor I; and adding xylose reductase and glucose dehydrogenase into the fermentation reaction liquid I, and carrying out second-step fermentation to obtain a fermentation product containing xylitol. According to the two-step enzyme catalysis method provided by the invention, xylitol is prepared, and high-purity xylose does not need to be used as a raw material; according to the present invention, the cheap hemicellulose hydrolysate can be directly adopted as the raw material, the xylose conversion rate and the xylitol yield can exceed 99%, the impurity arabitol content in the product is low, the other impurity saccharic acid is easy to separate, and the problems of complex process, large separation difficulty and high cost in the xylitol refining process are successfully solved.

A method for lignocellulose hydrolysis is provided. The method includes: crushing an agroforestry biomass feedstock, extracting with a toluene-ethanol solution, and drying to obtain a de-extracted feedstock; weighing a metal salt and glycerol for mixing to obtain a type IV deep eutectic solvent; weighing the de-extracted feedstock and adding into the type IV deep eutectic solvent, and reacting for 2 h-4 h at a temperature of 80° C.-120° C. and a stirring speed of 300 rpm-500 rpm to obtain a pretreatment mixture; performing a solid-liquid separation to the pretreatment mixture to obtain a filter residue and a filtrate, and then drying the filter residue after washing to obtain a lignocellulose residue after pretreatment; and performing enzymatic hydrolysis reaction to the lignocellulose residue to obtain fermentable sugar.

The application discloses a method for separating non-condensed lignin and saccharide compounds from deconstructed lignocellulose. The lignocellulose is used as raw material, and a high-boiling alcohol aqueous solution such as dihydric alcohol or trihydric alcohol is added into an acid molten salt hydrate as a deconstruction reaction system. The acid molten salt hydrate hydrolyzes hemicellulose and cellulose in the lignocellulose into saccharide compounds, and the high-boiling alcohol in the system acts as a lignin dissolving agent and a structure protecting agent, so that the lignin is dissolved in the high-boiling alcohol. Then, water is added to precipitate the lignin, so that the non-condensed lignin and the saccharide compounds are separated. The biomass deconstruction method can effectively promote the full-component utilization of three components of lignocellulose, and has great industrial application potential.

The invention discloses a recombinant bacterium for producing L-lactic acid through co-utilization of glucose and xylose as well as a construction method and application of the recombinant bacterium. The invention relates to the technical field of biology, in particular to recombinant bacteria for producing L-lactic acid through co-utilization of glucose and xylose as well as a construction method and application. Methylglyoxal synthase, and / or pyruvate formate lyase, and / or fumarate reductase and / or L-lactic dehydrogenase in receptor Escherichia coli Rec1.0 are modified to obtain recombinant Escherichia coli, the recombinant Escherichia coli is fermented for 24 h, L-lactic acid is the only metabolite, and the yield reaches 2458 g / L; the consumption rate of xylose is 0.76 g / g DCW / h, the consumption rate of glucose is 0.69 g / g DCW / h, and the consumption rate of total sugar reaches 1.45 g / g DCW / h. The recombinant Escherichia coli constructed by the invention can realize efficient utilization of lignocellulose hydrolysate (containing glucose and xylose), and has a wide application prospect.

A process for the liquefaction of cellulose, said process comprising:providing a source of cellulose; wherein said source of cellulose comprising cellulose and hemicellulose, wherein said source of cellulose is non-flowable;adding said source of cellulose to a mixing vessel; wherein said mixing vessel comprises a mixing apparatus selected from the group consisting of: a horizontal single helicoid auger flight; a horizontal double helicoid auger flight; a vertical single helicoid auger flight; a vertical double helicoid auger flight; a horizontal single ribbon auger flight; a horizontal double ribbon auger flight; a vertical single ribbon auger flight; a vertical double ribbon auger flight; a horizontal single sectional auger flight: a horizontal double sectional auger flight; and a vertical single sectional auger flight; a vertical double sectional auger flight;adding a solution to said mixing vessel containing said source of cellulose to yield a reaction mixture wherein said source of cellulose is present in a concentration of solids ranging from 5% to 50% of the total mass of said reaction mixture;mixing said reaction mixture in said mixing vessel until said reaction mixture has undergone liquefaction to yield a resulting mixture comprising oligomers and monomers from the degradation of cellulose and hemicellulose and wherein said resulting mixture has a resulting viscosity of no more than 15 Pa·s; andoptionally, separating said resulting mixture into a liquid stream used for subsequent processing and a solid stream that is introduced back into the mixing vessel for further processing.

The invention relates to the technical field of biology, in particular to pseudomonas fluorescens GS-1 for synthesizing polyhydroxyalkanoate and application of the pseudomonas fluorescens GS-1, the pseudomonas fluorescens GS-1 is preserved in China General Microbiological Culture Collection Center on February 6, 2026, and the preservation number is CGMCC No.37739; the strain carries a phaC gene and can synthesize PHA, and the straw sugar PHA conversion efficiency reaches 87.7% of that of a glucose system; the method has inherent lignocellulose hydrolysate inhibitor tolerance, and the PHA synthesis capability retention rate in the complex self-made corn straw saccharification liquid reaches 91.4%. A high-quality strain resource with direct application potential is provided for producing the PHA based on cheap straw saccharification liquid.

The invention belongs to the technical field of conversion and utilization of biomass materials, and relates to an acid-base synergetic solid catalyst, a synthesis method thereof and application of the acid-base synergetic solid catalyst in preparation of cellulose nanosheets. The solid catalyst provided by the invention has ortho-position weakly acidic and weakly alkaline sites, so that interlayer hydrogen bonds of cellulose can be selectively broken to prepare cellulose nanosheets. The synergistic effect of the zwitterions simulates the function of the ionic liquid, but the ionic strength of the ionic liquid is only suitable for preparation of nanosheets. A hydrolysis reaction is carried out under a microwave condition, and cellulose can be hydrolyzed into 2-D nanosheets within a short time. The method for preparing the cellulose nanosheets by synergistically destroying hydrogen bonds through the solid acid catalyst provides a new technical route for value-added utilization of cellulose.

The invention discloses a method for selectively preparing C6 ketone and 1, 2-hexanediol by accelerating cellulose hydrolysis based on a crude hydrogen atmosphere. The method comprises the following steps: by taking cellulose as a raw material, water as a solvent and activated carbon supported Pt as a catalyst, reacting for 1-6 hours under the conditions that the total pressure of hydrogen source gas containing CO and CO2 is 0.5-4.0 MPa and the temperature is 210-260 DEG C, and accelerating cellulose hydrolysis to obtain a product mainly comprising a C6 ketone compound and 1, 2-hexanediol; the catalyst is obtained by adding a pretreated carbon carrier into an ethanol solution, adding a platinum salt precursor solution, sealing, carrying out a hydrothermal reaction, carrying out suction filtration, washing and drying. According to the invention, the yield of C6 ketones is up to 53.4%, and the yield of 1, 2-hexanediol is up to 15.6%.

The present invention relates to a recombinant halomonas comprising an exogenously introduced xylose metabolic pathway and a metabolic pathway for synthesizing a copolymer of hydroxybutyric acid (HB) and lactic acid (LA), whereby the copolymer can be synthesized from a xylose-containing cellulose hydrolysate, the LA ratio can be controlled by further promoter modification and process optimization, and industrial enlargement is facilitated.

This invention discloses a mesoporous silica-based composite material with phosphotungstic acid simultaneously immobilized with titanium oxide and its cellulose hydrolysis method, belonging to the field of biomass catalytic conversion technology. This invention aims to solve the problems of easy desorption of active components, low catalytic efficiency, and poor cycle stability in existing solid acid catalysts during cellulose hydrolysis. This method uses an ionic liquid as the reaction medium and a titanium-silicon-supported phosphotungstic acid composite material with a two-dimensional hexagonal ordered mesoporous structure prepared by a one-step hydrothermal synthesis as the solid acid catalyst, catalyzing the hydrolysis of cellulose to reduce sugars in the presence of water. This invention achieves highly efficient cellulose conversion through the synergistic catalytic effect of the two acid sites combined with the good solubility of cellulose in the ionic liquid. The catalyst exhibits excellent recyclability, the process conditions are well-defined, it meets the requirements of green chemistry, and it is applicable to the field of biomass resource utilization.

A method for hydrolyzing cellulose into sugar to produce spherical capacitive carbon for the deep utilization of biomass and carbon materials. The present disclosure includes the following steps of: (1) crude cellulose pretreatment; (2) alkaline hydrolysis of cellulose; (3) separation of the cellulose from a hydrolyzed sugar liquor; (4) drying of an alkali-containing hydrolyzed sugar; (5) sintering of spherical capacitive carbon; (6) capacitive carbon post-processing; and (7) alkali recycling. In the method, biomass is used as a raw material, high-purity cellulose and hydrolyzed sugar are obtained through deep hydrolysis, the spherical capacitive carbon is sintered with the hydrolyzed sugar instead of sucrose and starch, and alkali is recycled. Pollution and waste are not generated, and more than 80% of the alkali can be recycled.

The invention discloses a construction method of engineering bacteria for producing glycerol and lipid by efficiently fermenting lignocellulose hydrolysate, and belongs to the technical field of microorganisms. The invention provides a method for producing glycerol and lipid by fermenting lignocellulose hydrolysate by using Candida glycinogenes which is resistant to high osmotic pressure as a production strain. According to the present invention, with the Candida glycyinogenes engineering strain Cg-AAGD constructed by using the method, the virus-free lignocellulose hydrolysate (containing about 175 g / L of glucose and 25 g / L of xylose) can be fermented to produce 82.2 g / L of glycerol and 7.3 g / L of lipid; according to the method, the lignocellulose hydrolysate is selected as a raw material, the purpose of deep resource utilization of agricultural waste is achieved, the related technological operation flow is relatively simple and convenient, and the requirement for production equipment is easy to achieve.

The invention belongs to the technical field of biology, and particularly relates to a method for producing xylitol by catalyzing hemicellulose hydrolysate through a biological enzyme, which comprises two stages: in the first stage, adding hemicellulose hydrolysate, xylose reductase, arabinose dehydrogenase and glucose dehydrogenase to form a fermentation system, adjusting the pH value of the system to 8.0-9.5, and fermenting, adding L-arabinose until no L-arabinose residue exists in the fermentation liquid to obtain a fermentation reaction liquid I; in the second stage, the pH value of the fermentation reaction liquid I is adjusted to 6.5-7.5, fermentation continues to be conducted, and a fermented product containing xylitol is obtained. According to the method for preparing the xylitol through the biological enzyme catalysis method, cheap hemicellulose hydrolysate can be directly adopted as a raw material, and high-purity xylose does not need to be used as the raw material; the xylose reductase, the arabinose dehydrogenase and the glucose dehydrogenase used in the method are wide in gene source, the three-enzyme one-pot catalytic process is simple and efficient, the conversion rate of xylose and the yield of xylitol both can exceed 99%, the content of impurity arabitol in the product is low, other impurity saccharic acid is easy to separate, and the method is suitable for industrial production. The problems of complex process, high separation difficulty and high cost in the xylitol refining process are successfully solved.

The invention discloses difunctional xylanase as well as a preparation method and application thereof. According to the bifunctional xylanase, a C-terminal Dockeren structural domain is knocked out on the basis of wild type xylanase Xyn1G3 as shown in an amino acid sequence SEQ ID NO. 1, and the amino acid sequence of the bifunctional xylanase comprises a sequence as shown in SEQ ID NO. 3. A novel bifunctional enzyme with a simplified structure and optimized functions is successfully constructed by directional knockout of a Dockeren structural domain through a genetic engineering means, the bifunctional xylanase not only retains the original activity of xylanase, but also shows remarkable activity of cellulose hydrolase, and the application potential of the bifunctional xylanase in biomass degradation is expanded.

A process to manufacture a value added product by blending a stream of cellulose-based hydrolysate with a non-cellulose based hydrolysate, wherein said process comprising the steps of: - providing a high purity cellulose comprising of less than 1.5 % lignin; - exposing said high purity cellulose to a saccharification process to produce a cellulosic hydrolysate comprising sugars obtained from the hydrolysis of cellulose and hemicellulose; - exposing said cellulosic hydrolysate to another sugar hydrolysate obtained from a saccharification of a non-cellulose based sugar source material, thus obtaining a combined hydrolysate stream; - processing said combined hydrolysate stream to produce SAID value-added product; and - optionally, purifying and / or separating said at least one value-added product from the rest of the fermentation stream to yield a purified value-added product.

The present application relates to a kind of lytic polysaccharide monooxygenase mutant and cellulose synergistic hydrolysis method.The present application belongs to the field of biotechnology, and traditional cellulose hydrolysis technology has the problems of low efficiency and high cost, the present application obtains mutant with higher catalytic activity and stability by site-directed mutagenesis to the 2nd and 43rd positions of the amino acid sequence shown in SEQ ID No:1, significantly improves cellulose hydrolysis efficiency, and has wide application prospect in the fields of bioenergy, papermaking, textile and the like.

The invention relates to a recombinant halomonas, which comprises an exogenously introduced xylose metabolic pathway and a metabolic pathway for synthesizing a copolymer of hydroxybutyric acid (HB) and lactic acid (LA), so that the copolymer can be synthesized through cellulose hydrolysate containing xylose, the production cost is reduced, and a new thought is provided for green manufacturing.

This invention discloses a reagent kit and method for the joint detection of glucose, cellobiose, and xylose in cellulose hydrolysate, belonging to the field of biomass conversion and analytical detection technology. The method includes the following steps: setting up three types of detection channels: a glucose oxidase detection channel that specifically responds to the glucose component; a β-glucosidase-glucose oxidase combined detection channel that responds to the total signal of glucose and cellobiose; and a pyranose oxidase detection channel that simultaneously responds to the combined signals of glucose, cellobiose, and xylose. Enzymatic colorimetric reactions are performed on the cellulose hydrolysate sample and the multi-component gradient standard solution in the three types of detection channels, respectively. A ternary linear calibration model is constructed based on the absorbance data of the three types of channels of the multi-component gradient standard solution. This method provides a rapid, low-cost, and highly specific detection method for glucose, cellobiose, and xylose in cellulose biomass hydrolysate, and has practical application value.

This invention discloses a genetically engineered bacterium for producing rhamnolipids and its applications, belonging to the field of gene recombination and metabolic engineering technology. The genetically engineered bacterium for producing rhamnolipids disclosed in this invention uses *Yarrowia lipolyticis* ATCC MYA-2613 as the starting strain and heterologously expresses the rhamnolipid synthesis gene. rhlA, rhlB and rhlC, and dTDP-L-rhamnose synthesis gene rmlA, rmlB, rmlC and rmlD This invention discloses a genetically engineered bacterium for producing rhamnolipin, which can efficiently metabolize glucose or glucose-containing cellulose hydrolysates to produce rhamnolipin, achieving a rhamnolipin yield of 42.8 g / L. The genetically engineered bacterium constructed in this invention provides a possibility for the efficient production of rhamnolipin from glucose or glucose-containing cellulose hydrolysates.

The invention discloses a root-promoting and water-retaining cellulose-based soil conditioner as well as a preparation method and application thereof. The soil conditioner provided by the invention is prepared from the following raw materials in parts by weight: 14 to 33.5 parts of acrylic acid, 10 to 32 parts of acrylamide, 12 to 32 parts of a silicon source, 10.5 to 28 parts of nano cellulose and 4.5 to 8.5 parts of amino acid chelate, the nano silicon dioxide-cellulose sol is obtained by hydrolyzing a silicon source and nano cellulose. The prepared soil conditioner is prepared by hydrolyzing a silicon source substance and cellulose into nano silicon in situ by virtue of an alkaline environment, the network structure of cellulose-based macromolecules is improved, the salt tolerance and the water-retaining property of the cellulose-based macromolecules are improved, and meanwhile, the soil conditioner contains root-promoting components such as amino acid chelate, silicon and potassium, so that the soil conditioner has a good application prospect. Therefore, the problem of lack of root-promoting bio-based soil conditioners is solved while soil water shortage in arid and semi-arid regions is overcome.

The invention relates to a lytic polysaccharide monooxygenase mutant and a cellulose synergistic hydrolysis method. The invention belongs to the technical field of biology, aims to solve the problems of low efficiency and high cost of the traditional cellulose enzymolysis technology, and provides a mutant with higher catalytic activity and stability by performing site-specific mutagenesis on the second site of an amino acid sequence shown in SEQ ID No: 1, so that the cellulose hydrolysis efficiency is remarkably improved, and the cost is reduced. The method has wide application prospects in the fields of biological energy, papermaking, spinning and the like.

The present application relates to a kind of lytic polysaccharide monooxygenase mutant and cellulose synergistic hydrolysis method.The present application belongs to the field of biotechnology, and traditional cellulose hydrolysis technology has the problems of low efficiency and high cost, the present application obtains mutant with higher catalytic activity and stability by site-directed mutagenesis to the 2nd amino acid sequence shown in SEQ ID No:1, significantly improves cellulose hydrolysis efficiency, and has wide application prospect in the fields of bioenergy, papermaking, textile and the like.

The invention discloses an acid-metal bifunctional catalyst for catalyzing cellulose to prepare isosorbide as well as a preparation method and application of the acid-metal bifunctional catalyst, the catalyst takes an acid-functionalized porous organic polymer as a carrier to load metal nanoparticles, the chemical general formula of the catalyst is M-PPh3-SO3H (at) POPs, and M is Ru, Pt, Pd or Ni. According to the catalyst, an acid active center is provided through a sulfonic acid group and used for cellulose hydrolysis and sorbitol dehydration, meanwhile, a hydrogenation center is provided through metal nanoparticles and used for glucose hydrogenation, and synergistic catalysis of acid-metal double active centers is achieved. The invention also provides a preparation method of the catalyst. The preparation method comprises the steps of carrier synthesis, acid functionalization and metal loading. The catalyst is applied to a reaction for directly preparing isosorbide from cellulose, the technological process can be remarkably simplified, the yield of isosorbide can reach 85% or above under the optimal condition, the catalyst is good in stability, and the activity retention rate exceeds 90% after the catalyst is repeatedly used five times.

The invention discloses a method for producing gamma-aminobutyric acid through double-bacterium synergistic fermentation of lignocellulose hydrolysate, and belongs to the technical field of microbial engineering. The method comprises the following steps: constructing a recombinant pediococcus acidilactici (Pediococcus acidilactici FR-XY) engineering bacterium, and constructing a recombinant pediococcus acidilactici (Pediococcus acidilactici) FR-XY; the method comprises the following steps: carrying out staged fermentation culture on lactobacillus hilgardii FR-1012 and recombinant pediococcus acidilactici FR-XY by utilizing lignocellulose hydrolysate, so as to obtain mixed fermentation liquor; centrifuging the mixed fermentation liquor, collecting mixed thalli, resuspending the mixed thalli in a conversion solution containing L-glutamic acid and coenzyme 5-phosphopyridoxal, and carrying out whole-cell conversion reaction to obtain a conversion solution containing gamma-aminobutyric acid. According to the method, the lignocellulose hydrolysate can be utilized for double-bacterium synergistic fermentation, and full utilization of a multi-element carbon source in the lignocellulose hydrolysate and efficient synthesis of gamma-aminobutyric acid are achieved.

A method for preparing levulinic acid from cellulose promoted by formaldehyde, which uses microcrystalline cellulose as raw material, organic solvent and water as mixed solvent, AlCl3·6H2O as catalyst, and formaldehyde as promoter to synthesize levulinic acid in a microwave reactor or a high-pressure reactor. The volume ratio of 2-methyltetrahydrofuran to water is 1:1-6:1. The method promotes the hydrolysis and subsequent conversion of cellulose by acetalization reaction between formaldehyde and the hydroxyl groups of glucose units in the structure of cellulose, has high efficiency of levulinic acid synthesis, generates less humin, has low boiling point of solvent, low energy consumption of separation, and is cheap and easy to obtain and separate.

The invention relates to a recombinant microorganism, which comprises an exogenously introduced xylose metabolic pathway and a metabolic pathway for synthesizing P34HB (poly-3-hydroxybutyric acid (3HB)-4-hydroxybutyric acid (4HB) ester), so that P34HB can be synthesized through cellulose hydrolysate containing xylose, the production cost is reduced, and a new thought is provided for green manufacturing.

The application provides a method for preparing furfural through catalytic hydrolysis of cellulose, which comprises using cellulose as raw material to efficiently prepare furfural through catalytic hydrolysis. Preparation of the hydrolysis catalyst mainly comprises the following steps: weighing a certain amount of combustible solid waste and placing it in a tube furnace, carbonizing for 2 hours in an N2 atmosphere. The black solid powder after carbonization is added into deionized water with an appropriate amount of ferric chloride and stirred to mix uniformly, then filtered, dried and calcined to complete loading. The dried solid is mixed with a certain amount of sulfuric acid in a polytetrafluoroethylene kettle and placed in an oven at 180 DEG C. After filtering and drying, the obtained hydrolysis catalyst is obtained. The cellulose hydrolysis step based on the above catalyst is as follows: the catalyst is mixed with a certain amount of cellulose according to a certain mass ratio and placed in a hydrothermal reaction kettle, an organic solvent is added, and the catalytic conversion reaction is completed under a certain reaction temperature and holding time. After cooling to room temperature, the solid-liquid mixture is taken out and filtered, and the obtained filtrate is rich in furfural.

This application relates to the technical field of *Fermentomonas motilityis*, specifically to engineered strains of *Fermentomonas motilityis*, complex proteins, and methods. The engineered strain is *Fermentomonas motilityis* containing genes encoding exoglucanase, endoglucanase, β-glucosidase, coliformin E protein, and a protein that interacts with the coliformin E protein. This engineered strain can efficiently express exoglucanase, endoglucanase, β-glucosidase, coliformin E protein, and the protein that interacts with the coliformin E protein, and facilitates the formation of complex enzyme assemblies, thereby increasing the enzyme activity and glucose yield in cellulose hydrolysis, and reducing the energy consumption of cellulose hydrolysis, thus possessing significant industrial application value.

The application discloses chitooligosaccharide from squid cartilage, and a preparation method and application thereof, and belongs to the technical field of amino polysaccharide extraction and application. The chitooligosaccharide is prepared from chitin obtained by desalting and deproteinization of squid cartilage, and a deproteinization process for obtaining the chitin is also provided. The chitin is prepared into beta-chitosan through deacetylation, and the beta-chitosan is prepared into chitooligosaccharide through cellulose hydrolysis. The preparation process of the chitooligosaccharide is simple and easy to implement. The characterization information of the prepared chitooligosaccharide is analyzed through experiments, the chitooligosaccharide contains oligomers with a polymerization degree of 2-6, and is a positively charged oligosaccharide. The application also provides application of the chitooligosaccharide in treatment and relief of type II diabetes. A large number of experiments prove that the chitooligosaccharide from squid cartilage has biological functions such as antioxidant, anti-diabetic, cholesterol-lowering, immune regulation and antibacterial activity, the prepared chitooligosaccharide from squid cartilage has relatively comprehensive biological functions, the preparation process is simple, and the chitooligosaccharide has wide application value in medicines and foods.