89 results about "Exoxylanase activity" patented technology

The invention provides a unique subset of GH30 subfamily 8 xylanases (GH30-8) with endo-β-1,4-xylanase activity, compositions comprising an effective amount of the GH30-8 xylanases, methods of synthesis and methods of use thereof.

The invention relates to an analyzing method for detecting activity of soil xylanase, which comprises the following steps: firstly, weighting n sieved air dry soil samples into n thick test tubes, adding acetic acid buffer solution into each test tube, oscillating by a vortex oscillator, getting soil suspension into 96 micropore plates under the oscillation condition, adding 4-MUB-7-Beta-D-xyloside substrate solution into n-1 holes, and adding water with equal quantity into the other one hole so as to be used as non-substrate contrast, adding substrate solution with equal quantity and water with equal quantity into the (n+1)th hole so as to be used as soli-free contrast, oscillating and culturing under constant temperature; secondly, adding NaOH into the micropore plates to terminate the reaction after the culture is finished; thirdly, performing the fluorimetric determination to resultant of reaction by a multifunctional microplate reader; and fourthly, calculating the activity of the xylanase. Compared with the traditional method, the invention shortens the culture time, omits the operation procedures of filtration, and the like, and simplifies the operation steps; meanwhile, the determination data of fluorescent materials in the micropore plate can be obtained within 15s through the multifunctional microplate reader, huge samples are allowed to be simultaneously determined; and moreover, the invention has high accuracy and easy operation, stable and reliable result and good reproduction quality.

The present invention relates to isolated polypeptides having xylanase activity and isolated polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods for producing and using the polypeptides.

An inactive xylanase molecule for the recovery of xylanase activity in plant-derived material containing active xylanase enzyme(s) and xylanase inhibitors. The inactive xylanase molecule of binds to xylanase inhibitors in the plant-derived material, thereby allowing accurate measurement of xylanase enzyme activity of the enzyme contained in the plant-derived material. The invention further includes amino acid molecules depicted by SEQ ID NOS. 4 through 112, wherein the catalytically active sites of each of the amino acids have been modified resulting in inactive xylanase molecules. A method of production of the inactive xylanase molecules includes expression of the inactive xylanase molecule in microbial or eukaryal (e.g., yeast including Pichia pastoris) host cell an expression cassette comprising a promoter operably linked to a nucleic acid molecule encoding the inactive xylanase molecule and using the expressed molecule in an assay to recover the xylanase enzyme activity in plant-derived material, for example, in plant-derived material such as animal feed.

The present invention relates to polypeptides having xylanase activity and polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods of producing and using the polypeptides. The invention also relates to compositions comprising the polypeptides of the invention and the use of the polypeptides of the invention to release xylose and in animal feed.

The invention provides a neutral high temperature xylanase CtXyn10A as well as genes and application thereof. The neutral high temperature xylanase CtXyn10A has proteins of amino acid sequences shown in SEQ ID No. 3 and/or SEQ ID No. 5 in a sequence table; and/or is characterized in that amino acid residue sequences shown in SEQ ID No. 3 and/or SEQ ID No. 5 in the sequence table are replaced and/or deleted and/or added by one or several amino acid residues, and have proteins with xylanase activity and derived from the proteins with the amino acid sequences shown in SEQ ID No. 3 and/or SEQ ID No. 5 in the sequence table. The xylanase CtXyn10A has an optimum pH of 6.0 to 7.0 and an optimum temperature of 70 DEG C, keeps enzyme activity of 20% or above at 90 DEG C and pH 9.0, and specific activity is 461 U / mg; the xylanase CtXyn10A has the activity of xylanase, glucanase and cellulase, is easy to produce by industrial fermentation, and can be widely used in food, paper, energy industry and the like as a novel broad-spectrum enzyme preparation.

The present invention is to provide a method for producing a material which contains xylo-oligosaccharides being rich in xylobiose and xylotriose, an antioxidant active substance and a dietary fiber, and which is useful as a food material and a health supplement, by a simple process, with efficiency, and at a low cost. The method comprises the steps of: subjecting a hemicellulose-containing plant resource such as bagasse to a steam treatment followed by an explosion treatment (2.5 Mpa, 70 seconds); mixing wheat bran into this steamed and exploded material; adjusting water content of this mixture to about 50%; subsequently, preparing koji with the use of a koji fungus having a high xylanase activity obtained by conducting single spore isolation from Aspergillus sojae (NFRI1147); adding water to the koji thus obtained; mixing the steamed and exploded material into a koji dispersion wherein koji is dispersed in water; adjusting water content of this mixture to about 50%; and subsequently, fermenting the mixture. After conducting the fermentation, a treatment to terminate the fermentation is conducted and the resultant is dried and then finely ground. As the steamed and exploded material to be mixed into the koji dispersion, 8- to 10-fold amount of the steamed and exploded material used for the koji preparation, is used.

The industrial process of producing xylanase with Aspergillus usamii belongs to the field of enzyme engineering technology. In the industrial process of producing xylanase, bagasse, corn cob, bran and other crop leftovers are used as the fermenting base material, and proper amount of inorganic salt, surfactant, water, etc are added for solid fermentation in a 30M3 solid fermenting tank with Aspergillus usamii E001 strain. The mature fermented material is stoved with hot blast at 45-50 deg.c to obtain xylanase product possessing xylanase activity of 7783-9616 IU/g. The present invention provides also the recipe of fermenting culture medium and the fermenting conditions.

Polypeptides with xylanase activity modified to increase bran solubilisation and/or xylanase activity. The modification comprises modification of one or more amino acids in position 113, 122 or 175 in combination with one or more further amino acid modifications in position 11, 12, 13, 34, 54, 77, 81, 82, 104, 110, 113, 118, 122, 141, 154, 159, 162, 164, 166, 175 or 179, wherein the positions are determined as the position corresponding to the position of Bacillus subtilis xylanase (SEQ ID NO 1).

The invention belongs to the technical field of biological engineering, in particular to a difunctional enzyme RuCelA with endoglucanase/xylanase and a preparation method and application thereof. The RuCelA sources from uncultured microorganism of rumen of Chinese yaks, and has a certain activity on phosphocellulose and filter. The RuCelA not only can hydrolyze polysaccharide but also can hydrolyze trisaccharide to obtain monosaccharide; meanwhile, the RuCelA has synergistic effect with xylanase to synergetically degrade xylan; and the RuCelA can be utilized to realize mono enzymatic degradation on preprocessed lignocellulose. The difunctional enzyme RuCelA of the invention can be widely applied to cellulose degradation, comprising cellulose biotransformation, chemical industry, spinning, food, bioenergy, feed ingredients, pharmaceutical Industry and other aspects.

Enzyme preparation (I) produced by fermenting wheat bran with an Aspergillus niger strain has glucoamylase, protease and xylanase activities of at least 100 U/g (dry basis), provided that the glucoamylase activity is at least 750 U/g and/or the xylanase activity is at least 300 U/g. An Independent claim is also included for the production of (I) by: (1) moistening and pasteurizing or sterilizing wheat bran; (2) inoculating an at least 10 cm thick layer of the bran with Aspergillus niger; and (3) fermenting the bran in an aerated and periodically agitated reactor at 28 - 38 degrees C for 1 - 3 days while maintaining the moisture content of the bran at 50 - 60 wt.%.

The present invention relates to polypeptides having xylanase activity and nucleic acid sequences encoding such polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the nucleic acid constructs as well as methods for producing and using the polypeptides. One specific application of the xylanase is the selective hydrolysis of pentose sugar components of hemicellulose-containing plant biomass. The nucleotide sequence may be used for the production of the xylanase or optimized mutants thereof.

The invention relates to a technique for preparing (FOs) feruloyl oligosaccharides by adopting a two-period-type combined regulation fermentation technology, belonging to the technical field of deep processing of agricultural and sideline products. The technique is characterized by comprising the following steps of: preparing a fermentation medium by adopting wheat bran as a main material, and regulating the initial pH and the initial temperature of fermentation liquor and then inoculating agrocybe aegevita and/or aureobasidium pullulans; and during the fermentation process, regulating the pH and the temperature of the fermentation liquor again, hydrolyzing wheat bran fibers by utilizing xylanase produced by microbes, so as to prepare the FOs. With the adoption of the technique, the reduction of the steps for preparing the FOs by adopting an enzymic method is facilitated; and the technique has the advantages of simple preparation process, low preparation cost and short preparation period, and can be used for improving the utilization ratio of wheat bran resources. Due to the adoption of the two-period-type combined regulation technology, the activity of the xylanase is ensured to be at the optimum level, so that the purpose of high yield of FOs is achieved. The technique is suitable for preparation of health-food-level FOs, and the yield of the FOs can reach 1123nmol/L.

A thermophilic endo-beta-1,4-xylanase derived from Acidothermus cellulolyticus is disclosed. The xylanase exhibits xylanase activity at an optimal temperature of 90° C. and an optimal pH range of about 4.5-6.0. The isolated xylanase is useful in the hydrolysis of lignocellulosic material.

The present invention relates to polypeptides having xylanase activity and polynucleotides encoding the polypeptides. The invention also relates to nucleic acid constructs, vectors, and host cells comprising the polynucleotides as well as methods of producing and using the polypeptides. The invention also relates to compositions comprising the polypeptides of the invention and the use of the polypeptides of the invention to solubilise xylan and in animal feed.