158 results about "Xylan" patented technology

The invention discloses an endoglucanase truncated mutant and an application of the endoglucanase truncated mutant. According to the invention, based on endoglucanase BsEGL from bacillus subtilis DLG, a truncated mutant is constructed by deleting a carbohydrate binding domain (CBM) of the endoglucanase BsEGL, and the truncated mutant is named as BsEGL [delta] CBM. Compared with BsEGL, the truncated mutant BsEGL delta CBM has the advantages that the thermal stability, the pH stability, the organic solvent tolerance and the like are remarkably improved, and the activity of degrading phosphoric acid expanded cellulose and corncob xylan is obtained. In addition, the enzymatic activity of the truncated mutant BsEGL delta CBM is remarkably improved by 6.41%, and the catalytic efficiency is remarkably improved. Due to the characteristics, the mutant can be suitable for industrial processes such as feed processing, papermaking, biological energy sources, spinning and food brewing, and is particularly suitable for enzyme catalytic reaction under extreme environments such as high temperature and low pH. The invention provides an enzyme preparation tool with excellent performance for efficient degradation of cellulose biomass, and has important application value.

The invention relates to bacillus megatherium XW-02 (the preservation number is CCTCC NO: M 2025185), a microbial preparation of the bacillus megatherium XW-02, and application of the microbial preparation. The bacillus megatherium XW-02 has the advantages that the preservation number is CCTCC NO: M 2025185; the strain can efficiently express xylanase through xylan induction, hemicellulose in tobacco leaves is remarkably degraded, chemical composition is optimized, and combustion harmful substances are reduced. The treated cigar has the advantages that the aroma richness is improved, the purity is improved, the taste mellowness is improved, and the overall quality is improved by 1-2 grades. The xylan extracted from agricultural wastes is used as an inducer to construct a green biological manufacturing system, the cost is reduced by more than 80% compared with the traditional process, and the emission of three wastes is reduced. The process compatibility is high, the method can be matched with an existing production line only by additionally arranging a strain culture module, the single-line annual tobacco leaf treatment amount reaches 500 tons, and economic benefits are remarkable. The invention provides a safe, efficient and environment-friendly quality improvement solution for the tobacco industry, and has great industrialization value.

The invention relates to a method for producing vanillin from natural lignocellulose biomass through co-culture of pichia pastoris, which comprises the following steps: respectively constructing a xylan hydrolysis recombinant strain (for releasing ferulic acid) and a vanillin synthesis recombinant strain (for converting ferulic acid) to realize conversion production from a natural xylan substrate to vanillin. In order to reduce the generation of by-products, 15 genes for coding aldehyde dehydrogenase (ALDRs), alcohol dehydrogenase (ADHs) and aldehyde ketoreductase (AKRs) are further knocked out from the vanillin synthesis recombinant strain, so that the vanillin can be further converted into the by-product vanillic acid, thereby improving the yield and purity of the vanillin.

The invention discloses a preparation method of a stable Pickering emulsion based on enzymic method modified whey protein microgel particle-araboxylan covalent composite particle, which comprises the following steps: preparing whey protein microgel particles by cross-linking glutamine transaminase, mixing the whey protein microgel particles with an araboxylan solution, and adding an enzyme method modified whey protein microgel particle-araboxylan covalent composite particle to prepare the Pickering emulsion. Adding horse radish peroxidase and a hydrogen peroxide solution to carry out enzymatic modification to obtain a water phase, mixing the oil phase and the water phase according to a volume ratio, carrying out IKA homogenization, and then carrying out ultrasonic treatment to obtain a Pickering emulsion with stable covalent composite particles; the preparation method is simple, harmful substances cannot be generated in the preparation process, and meanwhile, the preparation method is low in production cost, short in production period, rich in nutrition, green, free of pollution and high in economic utilization value; the obtained Pickering emulsion has high viscosity and excellent storage stability and environmental stability, an effective delivery carrier construction strategy is provided for construction of a fat-soluble and heat-sensitive bioactive micromolecule delivery system, and the application range of protein microgel particles in the fields of food, medicine and the like is widened.

The invention discloses boletus brownii xylan palmitate as well as a preparation method and application thereof. The boletus brownii xylan palmitate is xylan palmitate which is formed by alpha-(1-> 4)-xylose as a main chain, alpha-(1->)-glucose as a branch chain and palmitic acid molecules through ester bonds. The invention further discloses a preparation method of the boletus brownii xylan palmitate and application of the boletus brownii xylan palmitate in the aspect of immunoregulation. The boletus brownii xylan palmitate can be used as a dietary supplement or a food additive for immunodeficiency patients and tumor patients.

The invention belongs to the technical field of biodegradable high polymer materials, and particularly relates to a bagasse xylan modified biodegradable material and a preparation method thereof. According to the biodegradable material disclosed by the invention, on the basis of a traditional biodegradable material system, bagasse xylan phosphate is added as a modified material to replace part of raw materials, the bagasse xylan phosphate can effectively guarantee the daily mechanical property requirements of the biodegradable material, and the weather resistance is greatly improved; the application stability of the biodegradable material is effectively guaranteed.

The invention discloses application of GUX1 protein and related biological materials thereof in regulation and control of xylan glucuronic acid modification. Through overexpression of GUX1 in rice and tobacco, the invention finds that the short interval substitution of xylan glucuronic acid in an acceptor material is specifically increased. According to the invention, the function of short-interval glucuronic acid addition of GUX1 mediated xylan is found for the first time, and the GUX1 gene can be used for regulating a glucuronic acid modification mode of plant xylan and producing a corresponding xylan structure product, and is an important and valuable gene for cell wall structure and function modification.

The invention belongs to the technical field of biological medicine, and particularly relates to wheat bran araboxylan and application thereof. The invention provides wheat bran AX with specific molecular weight and monosaccharide composition. The wheat bran AX comprises the following monosaccharides: 0.20%-0.22% of glucuronic acid, 0.58%-0.62% of galacturonic acid, 0.21%-0.23% of rhamnose, 0.6%-0.7% of glucose, 1.4%-1.5% of galactose, 18%-19.2% of xylose and 21%-23% of arabinose. Compared with commercially available wheat bran AX, inulin, fructo-oligosaccharide and other common dietary fibers, the self-made wheat bran AX has higher diversity of microbial communities in the fermentation process, has a better intestinal flora regulating effect, further has a good relieving effect on the abnormal glucose and lipid metabolism of the body, and can be used for preventing and treating the abnormal glucose and lipid metabolism of the body. Therefore, the traditional Chinese medicine composition has a good regulation effect on various diseases such as non-alcoholic fatty liver and the like caused by abnormal glucose and lipid metabolism of the organism.

The invention discloses a dust suppression material based on calcium slow-release crosslinking. The dust suppression material comprises 2-6 parts of xylan, 9-85 parts of sodium chloroacetate, 0.12-0.85 part of calcium chloride, 0.6-1 part of citric acid, 1-2 parts of ethyl lactate, 24-56 parts of a basifier, 1-9 parts of a wetting agent and 1500-3000 parts of distilled water. Xylan is modified through carboxymethylation reaction, a calcium slow-release system is constructed to control the release rate of Ca < 2 + >, slowly released Ca < 2 + > is wrapped by carboxyl of adjacent xylan chains to form local crosslinking points, Ca < 2 + > serves as a molecular bridge, and linear molecular chains are connected into a stable three-dimensional network; the prepared dust suppression material has high wetting and permeability, high bonding strength, high water-retaining property, high environmental durability and a long-acting dust suppression effect.

The application discloses a nano zero-valent iron modified hemicellulose biochar composite material and a preparation method and application thereof. The preparation method comprises the following steps: mixing xylan raw materials and iron oxide, performing ball milling treatment, and then performing a carbothermic reduction process in a microwave pyrolysis device under a nitrogen protection atmosphere and a constant temperature condition, so as to obtain the nano zero-valent iron modified hemicellulose biochar material after cooling. The composite material is prepared by using the above preparation method. The composite material is applied to purification treatment of polluted wastewater containing chlorinated hydrocarbons. The composite material has low raw material cost, simple preparation method, can form stable structure pores, has good adsorption performance and catalytic activity, realizes molecular dispersion of zero-valent iron in a hemicellulose biochar matrix, and improves adsorption and reduction capacity of the composite material on chlorinated hydrocarbon pollutants.

The invention relates to the technical field of paper, in particular to white kraft paper with ultrahigh folding resistance and a preparation method of the white kraft paper. The method comprises the steps that bleached softwood and hardwood pulp are mixed and then shunted, part of pulp is oxidized through a TEMPO / NaBr / NaClO system and subjected to high-pressure homogenization treatment to obtain nanocellulose, and then the nanocellulose is compounded with base pulp; a xylan-chitosan interface reinforcing agent I and a chitosan-dihydrocaffeic acid-polyethylene glycol diglycidyl ether interface reinforcing agent II are prepared at the same time; the composite paper pulp, a reinforcing agent, cationic starch and other auxiliaries are sequentially mixed and then formed, and squeezing, steam drying and heat aftertreatment at 120-125 DEG C are carried out. The obtained kraft paper remarkably improves the folding resistance number through the synergistic effect of a multi-scale fiber network and interface reinforcement, has high strength, high flexibility and excellent whiteness, and is suitable for a high-frequency folding packaging scene.

The invention discloses bacteroides xylans Y1 and application of the bacteroides xylans Y1 in preparation of anti-inflammatory health care products or anti-inflammatory drugs. The preservation number of the bacteroides xylanisolvens Y1 is CGMCC (China General Microbiological Culture Collection Center) No.33145. The invention further discloses the application of the inactivated bacteria of the bacteroides xylanisolvens Y1 in preparation of anti-inflammatory health care products or anti-inflammatory drugs. Experiments prove that the inactivated bacterium of bacteroides xylanolyticum has an anti-inflammatory effect. The inactivated fermented milk prepared from the bacteroides xylanolyticum Y1 is simple in preparation process and convenient to operate, and the prepared inactivated fermented milk can significantly reduce the secretion level of proinflammatory factors NO, IL-6 and IL-1beta in a lipopolysaccharide (LPS)-induced RAW264.7 cell model, and has an anti-inflammatory function.

The invention relates to a method for producing a cellulose sheet having a xylan content of less than 25.0 percent by weight and having a tear index of at least 4.00 mN∙m2∙g-1, characterised by the combination of measures that straw, which contains lignin, xylan and cellulose and is suspended in an aqueous phase, is treated by means of an alkaline aqueous solution containing ethanol in order to reduce the lignin content, as a result of which a first cellulose is obtained, the first cellulose is treated with a xylanase in order to reduce the xylan content, as a result of which a second cellulose is obtained, and a cellulose sheet is formed from the second cellulose.

The invention discloses a Pichia pastoris indirect surface display system based on a TRAP protein scaffold, which is characterized in that Sed1p protein from saccharomyces cerevisiae is used as anchoring protein, and tetrapeptide repeat affinity protein TRAP is fixed on the anchoring protein on the surface of a Pichia pastoris cell to obtain the Pichia pastoris indirect surface display system based on the TRAP protein scaffold. The target protein with the carboxyl end fused with the peptide MEEVV or the peptide MRRVW is indirectly displayed on the surface of the pichia pastoris cell through specific binding with the tetrapeptide repeat affinity protein TRAP. The xylanase and the beta-xylosidase are indirectly displayed on the surface of the pichia pastoris cell by utilizing the surface display system, so that the pichia pastoris surface display system has the catalytic capabilities of the xylanase and the beta-xylosidase, can perform a synergistic effect to degrade the zelkova xylan, and has a good application prospect.

The invention discloses a preparation method and application of aminosalicylic acid xylan ester, and belongs to the technical field of glycan derivatives, the preparation method comprises the following steps: under the catalysis of diphenyl (2-hydroxyphenyl methyl) phosphine oxide, aminosalicylic acid and xylan are subjected to a reaction, and aminosalicylic acid modified xylan is prepared. In addition, the invention also provides an application of the aminosalicylic acid modified xylan in an animal breeding feed additive. According to the preparation method disclosed by the invention, the diphenyl (2-hydroxyphenylmethyl) phosphine oxide is utilized for catalysis, so that the aminosalicylic acid and the xylan are subjected to substitution reaction, complex functional group protection is not needed, and the yield and the purity are good; in the application of animal breeding feed, the modified product is added into the feed, so that the growth performance of bred animals such as chickens and the like can be remarkably improved, the intestinal morphology can be improved, and an efficient, simple and convenient preparation and application scheme is provided for feed additives.

The application discloses a xylanase mutant with simultaneously improved thermal stability and pH tolerance and application thereof, and belongs to the field of genetic engineering and protein engineering. The xylanase AbXyL10A from Agaricus bisporus var burnettii is used as a parent to obtain two xylanase mutants T234N and R268L after mutation of two amino acid sites Thr234 and Arg268. Compared with the wild-type xylanase, the thermal stability and pH tolerance of the two xylanase mutants are obviously improved. In terms of specific activity, when beech xylan is used as a substrate, the specific activity of the two xylanase mutants is obviously improved compared with the wild-type xylanase. The application provides a theoretical reference for improvement of xylanase, and the obtained xylanase mutant with simultaneously improved thermal stability and pH tolerance has great application prospect in animal feed and biomass degradation sugar.

The invention discloses a method for green synthesis of gold micron sheets by using xylan in cooperation with chloroauric acid, and belongs to the technical field of micro-nano materials. A green and environment-friendly biomass reagent xylan is used for synthesizing the gold micron sheet in a water phase system, and the specific preparation method comprises the steps that a polyvinylpyrrolidone solution is added into a chloroauric acid solution, xylan is added to serve as a reducing agent and a protective agent, and the gold micron sheet is obtained; effective nucleation and growth of the gold micron sheet are achieved by regulating and controlling the reaction temperature, the reactant mass concentration and the pH value of the gold precursor solution. The synthesized gold micron sheet is hexagonal, triangular and truncated triangular, the diameter is 1-6 microns, the sheet thickness is 100-150 nm, the sheet rate is higher than 80%, and the particle size of a small number of spheroidic gold particles is 0.1-1 micron. According to the method, the biomass reagent xylan is used, pollution of traditional chemical reagents to the environment is relieved, operation is easy and convenient, large-scale production is easy, the size and shape of the gold micron sheet are controllable, and an efficient method is provided for green synthesis of the gold micron sheet.

By using alkylated xylan, which is obtained by alkylating xylan, we provide a dispersant that can disperse carbon nanotubes (CNTs) at a high concentration in the organic solvent N-methyl-2-pyrrolidone (NMP), and a dispersion liquid with a high concentration of CNTs dispersed in it. [Solution] The present invention provides a CNT dispersant for dispersing CNTs in an organic solvent called NMP, characterized by using alkylated xylan, which is soluble in NMP, obtained by alkylating xylan. In the above configuration, the alkyl group to be alkylated may consist of any one group selected from a methyl group, an ethyl group, a propyl group, an isopropyl group, and a butyl group. By alkylating xylan, it becomes soluble in NMP, and the dispersion in which alkylated xylan is dissolved in NMP can disperse CNTs at a high concentration.

The present invention discloses a rhodamine B-doped silica / xylan carbon dot composite material and a preparation method thereof. In the method, rhodamine B and tetraethyl silicate are uniformly mixed to form RhB@SiO2. The carbon dots are covalently linked to the RhB@SiO2 to obtain RhB@SiO2 / BCD. A short DNA double helix is ​​formed by grafting a complementary chain onto the surface of the BCD, and a single-stranded aptamer with a quencher attached to one end is coupled to the carbon dots. The single-stranded aptamer specifically targets Vibrio parahaemolyticus. When Vibrio parahaemolyticus is present in the test sample, Apt.D detaches from the BCD surface and binds to a recognition site on the surface of the Vibrio parahaemolyticus, restoring fluorescence. Using the red fluorescence intensity R emitted by RhB@SiO2 as an internal standard, quantitative detection of Vibrio parahaemolyticus is performed based on the ratio of the blue fluorescence intensity B of BCD to R.

The present application belongs to the field of microbial technology, and particularly relates to Streptomyces louchei WA11-1-1 and application thereof. The Streptomyces louchei WA11-1-1 provided by the present application is isolated from Periplaneta americana, and the strain is currently preserved in the Guangdong Microbial Culture Collection Center with a preservation number of GDMCC NO.61629 and a preservation date of May 19, 2021. The Streptomyces louchei WA11-1-1 provided by the present application can convert 7-xylose-10-deacetyl paclitaxel into 10-deacetyl paclitaxel in fermentation, and under the conditions of a xylan concentration of 0.8%, a fermentation time of 4d, a fermentation temperature of 28℃ and a liquid loading of 250mL, the conversion rate can reach 40.72±1.08%, which is 1.85 times higher than that before optimization, and the Streptomyces louchei WA11-1-1 can be used for preparation of anticancer drugs and has a wide application prospect.

The invention particularly relates to a method for improving antifreeze activity of wheat bran araboxylan based on ion-induced spatial conformation rearrangement and application, and belongs to the technical field of food processing. The method is characterized in that wheat bran is used as a raw material, wheat bran AX with anti-freezing activity is obtained through urea alkali extraction and alcohol precipitation, ice shell separation and column chromatography, polysaccharide is subjected to conformation modification through Hofmeyer series ions, the anti-freezing activity of AX is remarkably improved, the ice crystal growth size inhibition effect is improved by 20%-86%, and the yeast survival rate is improved by 8%-47%. According to the method, polysaccharide spatial conformation rearrangement is induced through ions, the anti-freezing activity of AX is improved, and the method can be widely applied to frozen food preservation and biological sample low-temperature storage and has the advantages of being environmentally friendly, safe and low in cost.

The application discloses a kind of high stereoselectivity of alpha-xylopyranoside bond construction method, belongs to the technical field of sugar chemistry.The application uses full benzyl protected xylose trichloroacetimidate as glycosyl donor, by screening catalytic system, donor / acceptor ratio, additive type and molecular sieve type, optimize with trimethyl iodine silane as activating agent, triphenylphosphine oxide as additive high alpha-stereoselectivity glycosylation method.The method is mild in reaction condition, easy to operate, realizes the high stereoselectivity construction of 1,2-cis xylopyranoside bond without the action of participating group.Moreover, the method can be suitable for a variety of xylose donors with different protecting groups and a variety of glycosyl acceptors, to provide an effective means for efficient construction of a variety of alpha-xyloside and arabinoxylan modified by arabian mycin.

The invention refers to a composite mixture based on xylan hemicelulose esters, with improved thermal stability and hydrophobic properties and a method for obtaining it. The composite mixture, according to the invention, is used for surface treatment of paper for agri-food products packaging. The preparation process of the composite mixture involves, in the first stage, obtaining hemicellulose esters of the xylan type through an acetylation reaction between native xylan, ionic liquids based on imidazolium salts, and acetic anhydride. These are then mixed with other natural polymers (chitosan) and / or metal oxide nanoparticles (ZnO and CuO). The mixture is homogenized at a temperature of 20°C for 12...24 hours using magnetic stirring, and the specific properties of the food packaging are tested by applying the mixture as a layer / film with a mass of 2.5 - 5 g / m2 on each side of the paper / cardboard support, followed by drying for 10 minutes. The paper / cardboard treated with this composite mixture ensures protection of agri-food products against bacterial action and provides resistance to moisture, water vapor, oxygen, oils, and fats

This invention discloses the application of the BS1 protein in regulating plant vessel and pit structure and transport capacity. BS1 mediates acetylation modification of xylan at the pit edge, affecting the arrangement of nanofibers at the pit edge and the formation of pit structure, thereby influencing plant transport capacity. This invention is the first to discover that BS1-mediated acetylation modification at the pit edge plays an important role in pit nanostructure and morphology, as well as vessel transport capacity. Furthermore, BS1 It also mediates changes in pit structure under low-nitrogen treatment. Therefore, it can be controlled by regulating... BS1 The expression level or activity of rice under low nitrogen conditions, and the cultivation of rice with high transport capacity under low nitrogen conditions, have broad application prospects.

The application discloses a chaga acidic polysaccharide IOP-2 with anti-thyroid cancer activity and application thereof, and belongs to the field of biological medicines. The application adopts a method for extracting chaga polysaccharide by boiling water and precipitating chaga polysaccharide by ethanol, and combines DEAE cellulose column purification technology, and successfully realizes separation of chaga polysaccharide by using the principle that macromolecular polysaccharide is insoluble in organic solvents, and obtains chaga acidic polysaccharide IOP-2 with anti-thyroid cancer activity. The monosaccharide composition of the chaga acidic polysaccharide IOP-2 includes fucose 0.71%, rhamnose 3.33%, arabinose 2.18%, galactose 2.92%, glucose 80.59%, xylan 3.46% and mannose 6.81% in terms of molar percentage. The significant effect of the chaga acidic polysaccharide IOP-2 on anti-thyroid cancer is verified through in-vivo and in-vitro experiments, and a new treatment method is provided for clinical treatment of thyroid cancer.

The invention provides a sclerotinia sclerotiorum mutant strain SEEN10 and application of the sclerotinia sclerotiorum mutant strain SEEN10 in monocotyledon yield increase, and belongs to the technical field of microorganism application. The invention provides a Sclerotinia sclerotiorum mutant strain SEEN10, wherein a gene knocked out of the Sclerotinia sclerotiorum mutant strain SEEN10 is a xylan hydrolase gene SsXyl2 (SS1G03618), and the gene knocked out of the Sclerotinia sclerotiorum mutant strain SEEN10 is a xylan hydrolase gene SsXyl2 (SS1G03618). When the mycelium suspension of the strain SEEN10 is applied to seed dressing treatment of wheat seeds, compared with a wild sclerotinia sclerotiorum strain, the yield increase of monocotyledons can be more remarkably promoted, and the pathogenicity of the strain SEEN10 to oilseed rape is greatly reduced. The growth promoting advantage of the strain SEEN10 provides a technical path for green agriculture.

The application discloses a xylanolytic Bacillus sp CM263 and application thereof in phosphorus release and salt-alkali stress resistance, and belongs to the technical field of saline-alkali soil improvement. The xylanolytic Bacillus sp CM263 disclosed by the application has a preservation number of CGMCC No.38569. The xylanolytic Bacillus sp CM263 disclosed by the application is an advantageous strain which is extremely resistant to salt-alkali and can efficiently release phosphorus, and solves the technical problems in the prior art that microorganisms are difficult to survive in a high-salinity and high-alkali environment, have low phosphorus release activity, are not resistant to salt-alkali, have poor phosphorus release efficiency, and are not applicable to saline-alkali soil.

The invention relates to the technical field of microorganisms, in particular to a beta-1, 4-endo-xylanase gene BsxynA and application of the beta-1, 4-endo-xylanase gene BsxynA. According to the application, the beta-1, 4-endo-xylanase gene BsxynA is screened and identified, in-vitro induced expression is performed on the beta-1, 4-endo-xylanase gene BsxynA for the first time, and enzymatic properties of the beta-1, 4-endo-xylanase gene BsxynA are researched The enzyme activity of the bacillus safensis xylanase reaches 83.913 U / mL, the bacillus safensis xylanase is expected to be subjected to gene mutation through mutation breeding such as physical (such as ultraviolet rays and gamma rays) or chemical (such as nitrosoguanidine and diethyl sulfate) mutagenic agent treatment, and bacillus safensis mutants with higher enzyme activity are directionally screened. For example, ultraviolet mutagenesis can cause random mutation of the DNA of the microorganism, change the expression of the gene or the structure of the zymoprotein, and possibly increase the xylanase yield or enhance the xylanase activity. The produced BsXynA mainly promotes the hydrolysis of beech xylan, so that xylobiose (X2) and xylotetraose (X4) are generated, and xylose is not generated. In addition, the BsXynA significantly improves the digestive performance of the animal feed, and can increase the xylose content in the feed, promote the nutrient absorption of animals and reduce the production cost.

A cooking method and a digester system wherein partly digested cellulosic fiber source is compressed during cooking to provide high molecular weight xylan, high molecular weight lignin and pulp.

The invention relates to a process for extracting xylan compounds from comminuted wood components using hydrothermal extraction, wherein the hydrothermal extraction is carried out in a fixed-bed reactor with rapid circulation.