18 results about "Alkaline xylanase" patented technology

The present application relates to the field of genetic engineering and protein modification technology, and particularly relates to a novel basic xylanase mutant. The present application is based on wild-type xylanase H1, and provides a mutant containing at least one mutation site of Q24P, S38V / K / W / H / T / I, G40M / R / K / F / H, D41P, N56L / I / P / K, A57E / D / Y, A59K / R / I / M / H, H61F / Y, A75S, T80M, T103I, T107E, T114Y, D129L, Q132R / M, D135M, N143D, K144R, T149L, Q151N / Y, C154N, D157E, A160E, N165D, V166I, N167S / W, T177V, D192E. The tolerance of the mutant to high temperature and alkaline environment is significantly improved, which is beneficial to its wide application in the field of papermaking.

The application discloses a basic xylanase mutant with improved specific enzyme activity and thermal stability and a preparation method thereof, and belongs to the field of genetic engineering and enzyme engineering. The application provides a basic xylanase mutant M22 through a semi-rational design method, wherein the specific enzyme activity of the mutant M22 is 211 U / mg, which is increased by 181.33% compared with that of a wild type. After 30 min of heat treatment at 75 DEG C, the residual activity of the mutant M22 relative to the wild type is 169.30%, and after treatment at 80 DEG C, 85 DEG C and 90 DEG C, the relative residual activities of the mutant M22 are 153.94%, 127.84% and 115.02% respectively relative to the wild type treated at 75 DEG C for 30 min. The basic xylanase mutant M22 obtained by the application has significantly improved specific enzyme activity and stability compared with the wild type, and has higher application value and potential in industrial production.

The invention provides an alkali-resistant xylanase mutant and application thereof. The alkali-resistant xylanase mutant takes xylanase as a parent enzyme, the amino acid sequence of the xylanase is shown as SEQ ID NO.1, and the alkali-resistant xylanase mutant generates the following mutations relative to the parent enzyme: the 27th site, the 121st site, the 194th site, the 27th site and the 111th site of the parent enzyme are mutated into the 27th site, the 121st site, the 194th site, the 27th site and the 111th site of the parent enzyme, and the 27th site, the 121st site, the 194th amino acids of any one of the 27th site and the 194th site are mutated. Amino acid mutation sites of the five types of xylanase are found in total, the alkali stability and the high-temperature stability of the five types of xylanase mutants are obviously improved compared with those of wild type xylanase, and the specific enzyme activity is higher than that of the wild type xylanase. According to the five types of xylanase mutants, glutamic acid and aspartic acid with negative charges are replaced by lysine with positive charges on the surface, so that the protonation degree under the alkaline condition is improved, the hydration layer of xylanase under the alkaline condition is increased, the catalytic reaction is enhanced, and the activity of the xylanase under the alkaline condition is enhanced.

The present application belongs to the technical field of processing eucommia ulmoides, and particularly relates to a method for resolving and pulverizing residual hard-to-degrade plant tissues on eucommia ulmoides glue by using biological enzymes. The present application uses eucommia ulmoides shell crude glue as raw material, and resolves the raw material by using three biological enzymes in the following order: acid protease, alkaline xylanase and acid xylanase. Then, trace colored tissue debris and plant pigments attached to the G glue filament are removed by ultrasonic cleaning with a surfactant to obtain original flocculent eucommia ulmoides pure white fine glue. The acid protease enzymolysis conditions are as follows: pH 3.0, 55 DEG C oscillation for 48 h. The alkaline xylanase enzymolysis conditions are as follows: pH 7.2, 50 DEG C oscillation for 48 h. The acid xylanase enzymolysis conditions are as follows: pH 4.8, 50 DEG C oscillation for 72 h. The present application successfully separates and pulverizes the brown hard shell in the inner layer of eucommia ulmoides from the eucommia ulmoides glue filament, removes all non-glue plant tissues such as the outer epidermis and the hard shell in the inner layer of eucommia ulmoides shell, and obtains high-purity eucommia ulmoides glue after ultrasonic cleaning with a surfactant, with a purity as high as 98.94%.

The invention provides a method for making cigarette paper with pulp by enzyme-treated fiber pulp and a product and application thereof, and the method comprises the following steps: mixing the fiber pulp and enzyme, and carrying out reaction, enzyme deactivation and papermaking to obtain the cigarette paper, the fiber pulp comprises any one or a combination of at least two of hardwood pulp, softwood pulp or bamboo pulp; the enzyme comprises any one or a combination of at least two of hemicellulase, alkaline xylanase or neutral xylanase. The method provided by the invention can effectively degrade hemicellulose in the fiber pulp, can replace flax pulp to make cigarette paper, reduces combustion offensive odor, and significantly improves the tensile strength, burst index, tear index and other physical properties of the cigarette paper.

The invention relates to the technical field of genetic engineering and protein engineering modification, in particular to an alkaline xylanase mutant and application thereof. The invention provides a mutant containing an N165H mutation site on the basis of wild type xylanase H1. Compared with a wild type, the heat resistance of the xylanase mutant is remarkably improved, and wide popularization and application of the xylanase mutant in the industrial field are facilitated.

The present application relates to the field of genetic engineering and protein modification technology, and particularly relates to a novel basic xylanase mutant. The present application is based on wild-type xylanase H1, and provides a mutant containing at least one of the following mutation sites: Q24P, S38V / K / W / H / T / I, G40M / R / K / F / H, D41P, N56L / I / P / K, A57E / D / Y, A59K / R / I / M / H, H61F / Y, A75S, T80M, T103I, T107E, T114Y, D129L, Q132R / M, D135M, N143D, K144R, T149L, Q151N / Y, C154N, D157E, A160E, N165D, V166I, N167S / W, T177V, D192E. The tolerance of the mutant to high temperature and alkaline environment is significantly improved, which is beneficial to its wide application in the field of papermaking.

The present application relates to the technical field of genetic engineering and protein engineering, and particularly relates to a basic xylanase mutant and application thereof. The present application provides a mutant containing a N165H mutation site based on wild-type xylanase H1. Compared with the wild type, the heat resistance of the xylanase mutant is significantly improved, which is conducive to the wide promotion and application of the xylanase mutant in the industrial field.

The invention relates to the technical field of genetic engineering and protein engineering modification, in particular to a high-specific-activity alkaline xylanase mutant. The invention provides a mutant containing an H61L mutation site on the basis of wild type xylanase H1. The specific activity of the mutant is remarkably higher than that of a wild type, the production cost is reduced, and wide application of the mutant in the industrial field is promoted.

The present invention discloses a singeing-free descaling composite enzyme preparation, characterized in that, by weight percentage, it includes 10-14% amylase, 30-35% alkaline pectinase, 8-10% alkaline cellulase, 14-18% alkaline xylanase, 4-5% enzyme compounding agent, 1-2% anhydrous sodium carbonate, 7-11% chelating dispersant and 8-10% wetting penetrant. The present invention also discloses a pre-treatment method for cotton woven fabrics. The singeing-free descaling composite enzyme preparation of the present invention is applied to the padding and steaming pre-treatment of cotton woven fabrics, and a surface-engraved square roller and an ultrasonic generator are set in a washing box. Through the action of the composite enzyme preparation, impurities such as starch and pectin are decomposed, exposing more cellulose, reducing the connection between hairiness and the cloth surface, and removing the hairiness by strong water washing, significantly reducing the hairiness on the fabric surface. At the same time, under the synergistic effect of the composite enzyme and the auxiliary agent, the treated cotton woven fabric has a higher pectin removal rate and lower strength loss.

The present application relates to the field of genetic engineering and protein engineering, and particularly relates to a high specific activity alkaline xylanase mutant. The present application provides a mutant containing H61L mutation site based on wild type xylanase H1. The specific activity of the mutant is significantly higher than that of the wild type, which is beneficial to reduce the production cost and promote its wide application in the industrial field.

The present application relates to the field of genetic engineering and protein modification technology, and particularly relates to a high specific activity basic xylanase mutant and application thereof. The present application takes wild type xylanase H1 as a basis, and provides a mutant containing at least one of the following mutation sites: I37V, A59S, D63E, D104Y, T107M / K, N167G and D192E. Compared with the wild type xylanase H1, the specific activity of the xylanase mutant provided by the present application is generally increased by 8.5%-32.8%; wherein the specific activity of the xylanase mutant containing the D192E single point mutation is the highest, reaching 1625.11 U / mg, which is conducive to reducing the production cost of the enzyme and promoting its wide application in the industrial field.

The present invention discloses an alkaline xylanase and its multi-site mutants and applications. The present invention provides an alkaline xylanase that can exhibit good stability under alkaline conditions, the amino acid sequence of which is shown in SEQ ID No. 1; in order to further improve the stability and catalytic efficiency of the alkaline xylanase under alkaline conditions, the present invention performs multi-site mutations on the alkaline xylanase to obtain multiple multi-site mutants, each of which can maintain a high enzyme activity within the range of 50-55°C, exhibit better stability and catalytic efficiency under alkaline conditions, and can more efficiently convert the substrate xylan into the corresponding product while improving the substrate binding capacity. The present invention has application prospects in the large-scale production of xylan decomposition.

The invention discloses a high-enzyme-activity alkaline xylanase mutant and a preparation method thereof, and belongs to the field of gene engineering and enzyme engineering. According to the invention, heat-resistant and alkali-resistant xylanase derived from Bacillus halodurans is modified by a semi-rational design method, so that a series of combined mutants M1-M3 with high enzyme activity are obtained. The enzyme activity of the combined mutants M1-M3 is more than 3.5 times that of a wild type, and the enzyme activity of the optimal mutant M1 is 432.6% that of the wild type under the conditions of 70 DEG C and pH 9.0. The combined mutant provided by the invention can promote application in the fields of biomass resource utilization, food or papermaking industry, effectively solves the core problem of low enzyme activity in current xylanase application, and is more beneficial to application in industrial scenes.

The invention discloses alkaline xylanase as well as a multi-site mutant and application thereof. The invention provides alkaline xylanase which can show good stability under an alkaline condition, and the amino acid sequence of the alkaline xylanase is shown as SEQ ID No.1; in order to further improve the stability and catalytic efficiency of the alkaline xylanase under the alkaline condition, the alkaline xylanase is subjected to multi-site mutation to obtain a plurality of multi-site mutants, and the multi-site mutants can keep higher enzyme activity within the range of 50-55 DEG C; under the alkaline condition, better stability and catalytic efficiency are shown, the substrate binding capacity is improved, and meanwhile, the substrate xylan can be converted into a corresponding product more efficiently. The method disclosed by the invention has an application prospect in large-scale production of xylan decomposition.

The present invention relates to the fields of genetic engineering and protein engineering, and more specifically to an alkaline xylanase mutant with enhanced specific activity. Compared to the wild-type, the xylanase mutant has a specific activity increased by 32.83% to 1574 U / mg, which helps reduce production costs and promotes its widespread industrial application.

The present application provides a termite fungus and the produced alkaline xylanase and application. The screened termite fungus Isoptericola sp. WL6 belongs to alkaliphilic extremophiles, can be cultured under high alkaline conditions (pH 9.0), has the characteristics of effectively inhibiting the pollution of miscellaneous bacteria and being conducive to large-scale fermentation production. The alkaline xylanase protein produced by the termite fungus Isoptericola sp. WL6 has a molecular weight of about 43 kD, and the enzymatic property research shows that the optimal reaction temperature is 50 DEG C, the optimal reaction pH is about 8, especially between pH 6.5-10.5, the relative enzyme activity of the enzyme is all above 80%, which shows that the enzyme has good pH stability, strong stress resistance characteristics of both acid and alkali, meets the basic requirements of industrial enzymes such as papermaking and washing, and has good industrial application prospect.

The present application relates to the technical field of traditional Chinese medicine wastewater treatment, and specifically discloses a method for rapidly treating traditional Chinese medicine wastewater by using activated carbon immobilized enzyme, which comprises the following steps: activated carbon selection, activated carbon pretreatment, immobilized alkaline xylanase, activated carbon with immobilized enzyme treating traditional Chinese medicine wastewater, and filtering the water treated by activated carbon with immobilized enzyme; ordinary medium-speed filter paper is used for preliminary filtration to remove larger impurities and particles; then, a filter membrane with a pore size of 0.22-0.45 um is used for further filtration to remove smaller particles and impurities; and finally, the treated water is obtained. The present application can efficiently degrade natural organic polysaccharide pollutants in traditional Chinese medicine wastewater by using activated carbon immobilized enzyme, improve the biodegradability of wastewater, reduce membrane blockage, reduce operation cost, efficiently reduce the colority, COD, total nitrogen and ammonia nitrogen of the treated water, and thus simplify the traditional Chinese medicine wastewater treatment process and reduce the operation cost of a wastewater treatment plant.