68 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.

The invention relates to a preparation method of high-substitution-degree cationic micro-nano cellulose and application of the high-substitution-degree cationic micro-nano cellulose to improvement of water filtering performance of paper. In the enzymolysis pretreatment process, beta-1, 4 glucosidic bonds among glucose molecules are cut off, and more reaction binding sites are created for cationization after cellulose in an amorphous region and a part of crystalline region is hydrolyzed, so that the use amount of chemical reagents can be effectively reduced, and the environmental pollution is reduced. The prepared high-substitution-degree cationic micro-nano cellulose (CMFC) has abundant positive charges, weakens the hydrogen-bond interaction of cellulose molecules, improves the content of nano-fibrillation, and effectively reduces the mechanical preparation energy consumption of the CMFC. CMFC pulp is added into paper pulp fibers, so that pores of the paper fibers are blocked, more filler is intercepted, and the filler is difficult to be completely brought into white water by water flow in the water filtering process, so that the retention rate is increased, and the water filtering performance is effectively improved.

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 present invention relates to the technical field of deep learning, and discloses a method for detecting the antioxidant activity of oat seeds based on cellulase, including: crushing a plurality of oat seeds of different types into an oat flour set, performing cellulose hydrolysis on each oat flour in the oat flour set by using cellulase to obtain an oat hydrolyzate set, performing spectral imaging on the oat hydrolyzate set to obtain an oat spectral atlas set; performing keto-phenol detection on each oat hydrolyzate in the oat hydrolyzate set to obtain an oat component parameter group set, performing antioxidant detection on the oat hydrolyzate set by using the free radical scavenging method to obtain an antioxidant data set; training an antioxidant activity model by using the oat spectral atlas set and the oat component parameter group set to obtain an antioxidant analysis model; and analyzing the antioxidant activity of the to-be-detected oat seeds by using the antioxidant analysis model. The present invention also provides a device for detecting the antioxidant activity of oat seeds based on cellulase. The present invention can improve the efficiency of analyzing the antioxidant activity of oat seeds.

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.

The invention belongs to the technical field of cellulose hydrolysis, and discloses a construction method of a cellulose enzymolysis micro-homogeneous system and a recycling method of cellulase. In a water-phase system, a micro-homogeneous system is formed between the modified cellulase and cellulose, and the cellulose is subjected to enzymolysis; the preparation method comprises the following steps: introducing a polyethylene glycol derivative polyethylene glycol dibenzaldehyde FA-PEG-FA into an amino terminal of cellulase to obtain the modified cellulase, which is marked as FA-Cell. According to the method, a polyethylene glycol derivative is introduced to the amino terminal of the cellulase, so that the cellulase and cellulose form a micro-homogeneous reaction system under an aqueous medium, the enzymatic hydrolysis is prompted to be transited from a heterogeneous phase to a homogeneous phase, and the efficient recovery of the cellulase is realized by utilizing the pH sensitive characteristic of a dynamic Schiff base bond.

The invention discloses a pulping method of bleached chemical pulp, which comprises the following steps: (A) adjusting the concentration of pulp after cooking reaction with water, and adding bio-enzyme and oxidizing compound for oxygen removal reaction to obtain pulp after oxygen delignification; (B) bleaching the paper pulp subjected to oxygen delignification with chlorine dioxide to obtain bleached paper pulp; (C) carrying out alkali extraction on the bleached paper pulp to obtain the bleached chemical pulp, the biological enzyme is one or more of xylanase, hemicelluloses hydrolase, laccase, fiber oxidase, lignin peroxidase and multifunctional peroxidase. According to the method, specific bio-enzyme is added in an oxygen removal section, a common oxygen removal section is converted into bio-enzyme and oxygen bleaching delignification, delignification of a rear section is selectively improved, the load of front-section cooking can be released, the use amount of caustic soda for oxygen removal and cooking is reduced, and the production cost is reduced. Meanwhile, the oxygen removal efficiency, the subsequent bleaching efficiency and the sustainable production level of the paper pulp can be improved.

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%.

To provide a hydrolysis acceleration method of cellulose for decreasing molecular weight of cellulose in an organic sludge and a food residue while suppressing the carbonization rate.SOLUTION: In a hydrolysis acceleration method of cellulose with a carbon rate not exceeding 50% by hydrolysis treatment of an organic sludge including a food residue by a super heated steam reaction at 200°C or under while maintaining a water content of around 50% in the presence of a blended reaction acceleration agent including a crushed powder having an average grain size of 10 mm±5 mm in length including saw dusts, wood waste chips, dry straw, chaff, branches, barks, wood chips, and dry plants as the main component, in which the organic sludge is subjected to a contact reaction with a super heated steam of 300°C or under in a reactor for hydrolysis at 200°C or under so as to decrease molecular weight to hemicellulose. The reactor is assembled with a ribbon blender formed by providing an inner blade 152 and an outer blade 153 around a main inertial axis. A counter flow stirring motion wherein a stirred product flows to the inside by the outer blade, thus strong collision repeatedly occurs while the stirred product flows to the outside by the inner blade to collide with a side case and moves to the outer blade repeatedly occurs.SELECTED DRAWING: Figure 3

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.

Provided is a method for producing an organic compound, preferably ethanol, which includes bringing a liquid containing glucose into contact with a microorganism, wherein the liquid containing glucose is a hydrolysate of cellulose obtained by bringing a liquid containing cellulose and water into contact with a solid acid catalyst, and when the liquid containing glucose is subjected to LC analysis including a differential refractive index detector, the total area value of peaks derived from components having a lower molecular weight than glucose is 0.01-2.0 times and preferably 0.01-0.2 times the area value of peaks derived from glucose.

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 discloses a bimetallic oxide catalyst based on niobium oxide and a preparation method and application thereof, the molecular formula of the bimetallic oxide catalyst is MxNb (10-nx) / 5O5, M is one metal element of Ti, Y, Zr, Al, Cu, P and W, n is the valence of the metal element M, and x is the molar ratio of the metal element M to Nb. The bimetallic oxide catalyst based on niobium oxide is obtained through hydrolysis, the preparation method is simple, green and environment-friendly, the reaction process is controllable, the preparation repeatability is good, and the bimetallic oxide catalyst based on niobium oxide can be applied to the reaction for preparing levulinic acid by catalyzing cellulose hydrolysis. The bimetallic oxide catalyst based on niobium oxide has the advantages of strong stability, high product selectivity, high yield of levulinic acid, no toxicity and no pollution, and can efficiently promote the reaction in the process of preparing levulinic acid by catalyzing cellulose hydrolysis through niobium oxide. The problems that a traditional high-activity catalyst is low in product selectivity and a common catalyst is low in yield are solved.

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.