39 results about "Sucrase" patented technology

The present application relates to the technical field of biology, and discloses a construction method of a Pseudomonas putida suicide vector and application thereof.The construction method of the Pseudomonas putida suicide vector provided by the present application takes a pK18mobsacB vector as a template to obtain a vector skeleton by amplification, and then takes Pseudomonas putida KT2440 bacterial liquid as a template to obtain a strong promoter Prib, upper and lower homologous arms of a gene x to be knocked out, and connects the upper and lower homologous arms to the vector skeleton to obtain the Pseudomonas putida suicide vector.The strong promoter Prib can increase the expression amount of sacB sucrose in the Pseudomonas putida, and enhance the sucrose lethal effect.The Pseudomonas putida suicide vector obtained can be introduced into the Pseudomonas putida, and then the strain with the target gene to be knocked out deleted can be obtained efficiently and accurately through kanamycin positive screening and sucrose negative screening.

The invention discloses an amylosucrase mutant and application thereof in synthesis of alpha-arbutin, the mutant is obtained by mutation of an amino acid sequence of amylosucrase derived from coprophilobacterium mediterranei, and the amino acid sequence of the mutant is shown as SEQ ID NO.4. The invention further discloses a preparation method of the amylosucrase mutant. Compared with a wild strain, the catalytic activity, the temperature stability and the substrate tolerance of the amylosucrase mutant disclosed by the invention are remarkably improved; the recombinant bacteria constructed by using the recombinant bacteria can be used as a whole-cell catalyst to efficiently catalyze a substrate to synthesize alpha-arbutin in a reaction system containing hydroquinone. Therefore, the amylosucrase mutant disclosed by the invention has a good application prospect.

The invention discloses an amylosucrase mutant and application thereof in synthesis of alpha-arbutin, and belongs to the technical field of genetic engineering. An amylosucrase mutant is obtained through an error-prone PCR technology, the mutant is obtained by mutation on an amylosucrase amino acid sequence derived from coprophilobacterium mediterranei, and the amino acid sequence of the amylosucrase mutant is shown as SEQ ID NO.4. The invention further discloses a preparation method of the amylosucrase mutant. Compared with a wild strain, the amylosucrase mutant disclosed by the invention has higher catalytic activity, temperature stability and substrate tolerance; when the catalyst is added into a hydroquinone-containing reaction system, alpha-arbutin can be efficiently catalyzed and synthesized. Therefore, the amylosucrase mutant disclosed by the invention is suitable for industrial production and has a good application prospect.

The invention discloses a sucrase mutant, an expression strain of the sucrase mutant and application of the sucrase mutant in hydrolysis of carbohydrates in soybean milk, and belongs to the technical field of biology. The sucrase mutant disclosed by the invention is simply recorded as InvDz13-TBT-01, and the amino acid sequence of the sucrase mutant is shown as SEQ ID NO: 2. The sucrase mutant InvDz13-TBT-01 is subjected to heterologous expression in bacillus subtilis, a recombinant strain is obtained, and the specific enzyme activity and the stability of protein produced by fermentation of the recombinant strain are remarkably improved. When sucrose is used as a substrate, the specific enzyme activity of the mutant enzyme is improved by 1.94 times, and when raffinose is used as a substrate, the specific enzyme activity of the mutant enzyme is improved by 1.7 times. Under the condition of 35 DEG C, the stability of the mutant enzyme is improved by 4 times. Compared with the starting enzyme, the thermal stability of the mutant enzyme is greatly improved while the specific enzyme activity is maintained. The sucrase mutant disclosed by the invention has a potential value in the application of hydrolyzing carbohydrates such as raffinose in soybean milk.

The present application relates to a kind of recombinant starch sucrolase and its application in the production of resistant starch, belong to the technical field of enzyme engineering.The present application first prepares a kind of preparation method of recombinant starch sucrolase, starch sucrolase derived from polysaccharide Neisseria (Neisseria polysaccharea) is expressed in escherichia coli heterologously, and can significantly improve the activity of starch sucrolase by signal peptide and strengthen expression.Further, the recombinant starch sucrolase is applied to the preparation of resistant starch, and can significantly improve the production efficiency of resistant starch.

The invention relates to the technical field of food processing, in particular to zanthoxylum armatum oil extracted based on enzymolysis-high-voltage pulse combined assistance and a preparation method thereof. The preparation method comprises the following steps: enzymolysis treatment: blending zanthoxylum armatum and a compound enzyme solution at 45-55 DEG C, wherein the compound enzyme solution comprises alkaline protease, sucrase and cellulase; high-voltage pulse treatment: the electric field intensity is 1.2-1.5 kV / cm, the pulse width is 15-20 microseconds, and the treatment time is 6-9 minutes; solvent extraction: performing centrifugal separation after edible oil extraction. According to the technical scheme, through the synergistic effect of the enzymolysis method and the high-voltage pulsed electric field technology, heat-sensitive flavor and numb-sensitive substances in the zanthoxylum armatum raw materials are reserved to the maximum extent while efficient extraction is achieved.

The present invention discloses compositions comprising methylxanthines in combination with disaccharides derived from enzymatic conversion of sucrose. More particularly, the present invention discloses compositions comprising methylxanthines and disaccharides derived from enzymatic conversion of sucrose selected from turanose, leucrose, trehalulose and isomaltulose or in combinations thereof.

The application discloses a kind of fast swelling, enzyme catalytic degradation hydrogel and its preparation method and application, in the present application based on by sucrose molecule connection multi-arm hydrophilic polymer crosslinked hydrogel, and the swelling rate is fast, and the swelling rate is high, and in the environment of sucrose enzyme degradation rate is fast, can be widely used for preparing in enzyme response biodegradable hydrogel carrier and promote weight loss product.

The invention discloses an amylosucrase mutant and application thereof in synthesis of alpha-arbutin, and belongs to the technical field of genetic engineering. An amylosucrase mutant is obtained through an error-prone PCR technology, the mutant is obtained by mutation on an amylosucrase amino acid sequence derived from coprophilobacterium mediterranei, and the amino acid sequence of the amylosucrase mutant is shown as SEQ ID NO.4. The invention further discloses a preparation method of the amylosucrase mutant. The amylosucrase mutant can be used for synthesis and preparation of alpha-arbutin, the amylosucrase mutant is used as a biocatalyst to convert substrate hydroquinone to generate alpha-arbutin, and the reaction conversion rate of the reaction is proved to be high. Compared with a wild type enzyme, the amylosucrase mutant constructed by the invention has the advantages that the catalytic activity, the temperature stability and the substrate tolerance are obviously improved, the production cost is reduced, and the industrial application value of the amylosucrase is effectively improved.

The application discloses a new application of Korla fragrant pear high-activity polysaccharide in promoting expression of small intestinal disaccharidase, and belongs to the technical field of functional food and medicine. In the application, Korla fragrant pear pulp is freeze-dried, ground, sieved, extracted with hot water, alcohol precipitated, decolorized and deproteinized, separated through a membrane filtration system, further purified through DEAE-Fast flow anion exchange column chromatography, and finally, Korla fragrant pear high-activity polysaccharide KPP-2-a is obtained. The application innovatively finds that KPP-2-a can effectively promote expression and activity of disaccharidase (lactase, sucrase and maltase) in the brush border of small intestinal mucosal epithelial cells, significantly improves secondary disaccharidase deficiency and related symptoms, excavates a new use of the Korla fragrant pear high-activity polysaccharide KPP-2-a and widens the application field thereof, provides a new means for intervention of secondary disaccharidase deficiency, and has a broad prospect and market value.

The invention belongs to the field of biological medicine, and particularly relates to preparation and application of dextran for relieving ulcerative colitis. The dextran GS128 is formed by directly catalyzing and synthesizing dextransucrase Gtf128 generated by heterologous expression in vitro by taking sucrose as a substrate, and the product is obtained by ethanol precipitation, centrifugation, dissolution and dialysis. The compound shows high anti-digestion performance in the process of simulating gastrointestinal tract digestion, and can relieve the symptoms of ulcerative colitis by inhibiting oxidative stress, adjusting the balance of proinflammatory / anti-inflammatory factors and improving the colon barrier.

One aspect of the present invention relates to an oral hygiene enzyme complex for use in the treatment of dental plaque and plaque bacterial biofilms and for the natural whitening of enamel, the complex comprising a combination of the following compounds: sucrase enzymes, particularly those capable of hydrolyzing the β-2,6 and / or β-2,1 bonds of sucrose; a mixture of glucanohydrolase enzymes, including mutanases having exolytic activity and obtained from fungi, and mutanases having endolytic activity and obtained from bacteria, particularly those capable of hydrolyzing (1→3)-α-D-glucans and (1→6)-α-D-glucans; glycoside hydrolase enzymes, particularly those capable of hydrolyzing the (1→6)-α-D-glycosidic bond in monosaccharide dimers and trimers; oxidoreductases, particularly those capable of producing hydrogen peroxide from glucose and monosaccharide monomers; and peroxidase enzymes, particularly those capable of converting thiocyanate to hypothiocyanate in the presence of hydrogen peroxide.

The invention relates to the technical field of animal breeding, and discloses a method for adjusting the activity of urease and sucrase in lumbricus intestinal tracts. The invention provides application of microalgae in enhancing the activity of urease and sucrase in the intestinal tract of lumbricus, microalgae cell sap containing scenedesmus, chlorella or a combination of scenedesmus and chlorella is used after being mixed with a basic feed for culturing lumbricus, or is directly applied to a culture medium, so that the growth traits such as weight and length of lumbricus can be remarkably improved, and meanwhile, the growth of the lumbricus is improved. By improving the activities of urease and sucrase in the intestinal tract of the lumbricus, the digestion and metabolism efficiency of the lumbricus on a nitrogen source and a carbon source is effectively improved, the problems of low feed utilization rate and slow growth in breeding are fundamentally solved, the standardization and sustainable development of the lumbricus breeding industry are powerfully promoted, and a guarantee is provided for exerting the ecological and medical values of the lumbricus.

The application discloses a method for relieving corn phytotoxicity caused by triazole fungicide seed dressing, and relates to the technical field of crop plant protection and seed treatment. The application discloses that straw source tobacco water can be used for relieving corn phytotoxicity caused by triazole fungicide seed dressing. The specific application mode is as follows: after the straw source tobacco water is diluted to a specific concentration, the straw source tobacco water is compounded with triazole fungicide to prepare a mixed pesticide; and the mixed pesticide is used for seed dressing treatment of corn seeds. Through test verification, the application proves that the straw source tobacco water can improve the germination ability of corn seeds after triazole fungicide seed dressing, promote the growth of corn seedlings, improve the activities of alpha-amylase, plant sucrose and antioxidant enzymes in the corn seeds, increase the content of reduced glutathione, and reduce the contents of malondialdehyde and superoxide anion, so as to relieve the corn phytotoxicity caused by triazole fungicide.

The invention discloses an amylosucrase mutant and application thereof in synthesis of alpha-arbutin, and belongs to the technical field of genetic engineering. An amylosucrase mutant is obtained through an error-prone PCR technology, the mutant is obtained by mutation on an amylosucrase amino acid sequence derived from coprophilobacterium mediterranei, and the amino acid sequence of the amylosucrase mutant is shown as SEQ ID NO.4. The invention further discloses a preparation method of the amylosucrase mutant. Compared with a wild type strain, the catalytic activity, the temperature stability and the substrate tolerance are remarkably improved; recombinant bacteria constructed by the method can be used as a whole-cell catalyst, and alpha-arbutin is efficiently catalyzed and synthesized by taking hydroquinone as a substrate and sucrose as a glycosyl donor. Therefore, the amylosucrase mutant disclosed by the invention has a good application prospect.

The invention discloses an RNA-carried pesticide nanomotor capable of efficiently killing sogatella furcifera and a preparation method of the RNA-carried pesticide nanomotor, and belongs to the technical field of plant protection. The method comprises the following steps: S1, preparing silicon dioxide nanoparticles with a virus surface imitating branch morphology; s2, carrying out mask-assisted selective functionalization and polyelectrolyte layer-by-layer self-assembly, and asymmetrically loading glucose oxidase and sucrase on the surfaces of the nanoparticles; s3, synthesizing double-stranded RNA (Ribonucleic Acid) of the targeted sogatella furcifera chitin synthase gene; and S4, loading the double-stranded RNA on a product obtained in the step S2. The nano-motor disclosed by the invention can decompose cane sugar in rice juice by utilizing a double-enzyme cascade reaction to generate a chemical gradient, so that autonomous chemotactic movement is realized, a vascular bundle end wall barrier of rice is effectively broken through, and an RNA pesticide is efficiently delivered to target pests, so that efficient and specific killing of sogatella furcifera is realized. The method has the advantages of being simple in synthesis, controllable in size, excellent in movement performance, large in loading capacity, environmentally friendly and the like.

The application belongs to the field of enzyme-catalyzed synthesis of organic compounds, and particularly relates to a mutant of amylosucrase, a solidified enzyme, a preparation method of the solidified enzyme and a glycosidase catalytic synthesis method, wherein the mutant of amylosucrase is an amino acid sequence with at least one mutation of N210T, R131K and S450T in a wild amino acid sequence shown in SEQ ID NO. 1. The mutant has excellent activity, stability and substrate tolerance.

The invention discloses levan sucrase as well as a mutant, a recombinant expression vector and application thereof, and belongs to the technical field of bioengineering. The amino acid sequence of the fructan sucrase is as shown in SEQ ID NO.2 or SEQ ID NO.4, and the amino acid sequence of the fructan sucrase mutant is as shown in SEQ ID NO.8. The invention further discloses a preparation method of the fructan sucrase mutant. The recombinant expression vector contains the coding gene of the levan sucrase or the mutant of the levan sucrase. The invention also discloses application of the fructan sucrase and the mutant thereof in hydrolysis of cane sugar or synthesis of kestose. The specific activity of the fructan sucrase is 66.17 U / mg, a fructan sucrase mutant with higher enzyme activity and higher thermal stability is obtained after mutation modification of the fructan sucrase, and the specific activity of the fructan sucrase mutant is 169.37 U / mg. The fructan sucrase and the mutant thereof can be used for hydrolysis of cane sugar and synthesis of kestose, and have a good application prospect.

The invention discloses a mixed bacterial agent ZL3 + 6 with effects of promoting growth of haloxylon ammodendron and regulating rhizosphere microflora and application of the mixed bacterial agent ZL3 + 6, and belongs to the technical field of microorganisms. According to the bacillus orientalis ZL3 and the bacillus cereus ZL6 provided by the invention, the conversion of soil nutrients to available nutrients is improved, and the rhizosphere microbial community structure is improved, so that the effect of promoting the growth of haloxylon ammodendron is achieved. When the ZL3 and the ZL6 are mixed and applied to a haloxylon ammodendron field, the contents of hydrolytic nitrogen, available phosphorus and rapidly available potassium in soil and the activity of sucrase are remarkably improved and are respectively improved by 49.27%, 80.48%, 12.65% and 64.40%. The plant height is increased by 51.75%, and the root length is increased by 262.18%. Meanwhile, the positive change of microbial communities is regulated and controlled, especially the enrichment of beneficial bacteria, the relative abundance of the prevotella and the vibrio is remarkably increased, and the relative abundance of the burkholderia is remarkably reduced. In general, the ZL3 + 6 inoculant is inoculated to promote the growth and development of haloxylon ammodendron by improving the soil fertility and improving the rhizosphere microflora structure.

The application discloses a construction method of a fusion enzyme Escherichia coli engineering bacterium capable of directionally synthesizing high molecular weight dextran and application thereof, and the construction method comprises the following steps: taking a P473S dextran sucrase gene and a dextranase BMdex gene as templates, homologously recombining two enzyme genes according to a catalytic order, and transforming the two enzyme genes into BL21 (DE3) Escherichia coli to obtain a fusion enzyme Escherichia coli BL21 (DE3) / dex-P473S-BMdex gene engineering bacterium capable of directionally synthesizing dextran with different high molecular weights. The dex-P473S-BMdex gene engineering bacterium constructed in the application can produce the fusion enzyme capable of directionally synthesizing high molecular weight dextran through fermentation expression; and 1500kDa dextran with concentrated molecular weight can be directly obtained through the catalysis of the fusion enzyme with sucrose as a substrate.

The present application relates to a kind of specific synthesis plant inulin of inulin sucrose enzyme mutant and its application, the mutant is the 300th aspartic acid of wild type inulin sucrose enzyme from Lactobacillus reuteri (Lactobacillus reuteri) Limosilactobacillus reuteri ) Mutated into alanine.It precisely cuts off the ability of wild type enzyme to synthesize million Dalton high molecular weight microbial inulin at molecular level, while perfectly retaining the synthesis ability of medium-low degree of polymerization inulin.This mutant fundamentally solves the problem of wild type enzyme product molecular weight distribution extremely wide, component complex, realizes the efficient biosynthesis of specific inulin.At the same time, it can greatly reduce the difficulty and energy consumption of downstream separation and purification process, significantly reduce production cost.In the high-quality inulin large-scale green manufacturing of food and health product industry, it has great application value.

The invention belongs to the field of biological pharmacy and biological conversion, and particularly relates to an amylosucrase mutant, a mutant encoding gene, a recombinant vector containing the mutant encoding gene, a recombinant genetic engineering bacterium containing the mutant encoding gene and application of the amylosucrase mutant in preparation of (E)-resveratrol glucoside by an enzyme method. The amylosucrase mutant disclosed by the invention shows efficient 4 '-alpha-G-Res synthesis capability, and the final concentration of the product can reach 20g / L. The conversion rate of the substrate resveratrol is high and reaches 70.3%, and the conversion rate of the wild type enzyme is only 11.6%. The regioselectivity of the glycosylation site of 4 '-OH is high (82%). The amylosucrase mutant disclosed by the invention shows good 4 '-OH regioselectivity, also has efficient resveratrol glycosylation ability, and shows good industrial application value in the aspect of 4'-alpha-G-Res preparation.

The application discloses a starch sucrolase mutant capable of changing starch chain length and application thereof in preparation of long-chain amylose, and belongs to the technical field of genetic engineering. The application provides a starch sucrolase mutant, wherein the mutant is obtained by mutating the amino acid at the 340th position of the amino acid sequence of the starch sucrolase shown in SEQ ID No. 1. The starch sucrolase mutant of the application has changed starch chain length distribution relative to modified wild type, and has equivalent enzyme activity, so that the application of the enzyme in the actual industrial application can be widened, and the starch sucrolase mutant has good industrial application prospect.

The invention discloses a dendritic composite virus-morphology-imitated high-molecular nano motor as well as a preparation method and application thereof, and belongs to the technical field of plant protection. The method comprises the following steps: preparing dendritic polycation macromolecules (DP) and virus-like silicon dioxide nanoparticles; modifying the DP on the surfaces of the virus-like nanoparticles through interface self-assembly; and finally, sequentially loading beta-glucanase, sucrase and double-stranded RNA (Ribonucleic Acid) of a targeted phytophthora capsici Ces3 gene. The obtained nano-motor can realize chemical chemotactic movement by utilizing cascade catalysis of sucrase / beta-glucanase and degrade beta-glucan of cell walls of pathogenic bacteria, so that the RNA pesticide is actively navigated and efficiently delivered to a target. The nano motor prepared by the invention has the advantages of strong motility, high barrier penetration efficiency, large loading capacity, environmental friendliness and the like, and provides a brand new strategy for green prevention and control of phytophthora capsici.

A method allows people to not compromise on the taste and flavor of sugar-containing foods and beverages, while reducing the net effect of the sugar in the body. The method may include oral consumption of the enzyme alternansucrase to convert up to 90% of consumed sucrose and other carbohydrates into a carbohydrate complex of undigestible or slowly digestible α-1, 3 and α-1, 6 glucan fibers in the gastrointestinal tract. These glucan fibers have the properties of dietary fibers and a degree of polymerization ranging from 3 to greater than 100. The methods may aid in glucose control, reduce insulin resistance and support healthy glucose homeostasis in diabetic and pre-diabetic conditions. It may promote healthy gut bacteria and improve bowel movements to benefit overall digestive health. It may also be applied to obesity control by reducing blood glucose and, through the production of fiber, blood lipid levels, which supports cardiovascular health.

The application discloses application of a composite biological enzyme preparation in preparation of a product for improving chemical liver injury, and relates to the technical field of biotechnology.The raw materials of the composite biological enzyme preparation include 3-14 kinds of papain, bromelain, acid protease, pepsin, trypsin, alpha-amylase, sucrase, lipase, cellulase, pectinase, glucoamylase, nuclease, serrapeptase and beta-galactosidase.The composite biological enzyme preparation can significantly improve chemical liver injury, effectively reduce serum ALT and AST activity, relieve liver cell degeneration, necrosis and inflammatory infiltration, and reduce liver tissue inflammatory factor level;for alcoholic liver injury, the composite biological enzyme preparation can improve serum and liver ADH and ALDH activity, promote alcohol metabolism, regulate four blood lipid indexes, reduce liver index and liver MDA content, and reduce liver oxidation damage.

The present invention relates to a composition for lowering blood glucose, comprising a Citrus unshiu leaf extract. The composition containing a Citrus unshiu leaf extract according to the present invention has a high hesperidin content and excellent α-glucosidase inhibitory activity and sucrase inhibitory activity. In addition, the composition comprising a Citrus unshiu leaf extract, of the present invention, has no cytotoxicity, and thus can be safely used in the human body. Therefore, the composition comprising a Citrus unshiu leaf extract, according to the present invention, is expected to be very effectively used as a pharmaceutical composition, a functional food composition, and a feed composition, for lowering blood glucose or preventing diabetes.

The invention belongs to the technical field of traditional Chinese medicine pharmacy, and relates to a compound active component with an auxiliary hypoglycemic effect and a preparation method thereof. The preparation method comprises the following steps: mixing 4-6 parts by mass of kudzuvine root, 9-11 parts by mass of corn stigma, 5-7 parts by mass of codonopsis pilosula, 11-13 parts by mass of mulberry, 5-7 parts by mass of rhizoma polygonati, 11-13 parts by mass of medlar and 3-5 parts by mass of eucommia male flower, performing water extraction to obtain a water extract, adding 2-4 parts by mass of guava juice and 3-5 parts by mass of inulin into the water extract, and concentrating until the relative density is 1.10 at the temperature of 20 DEG C to obtain concentrated liquid medicine; and extracting the concentrated liquid medicine for multiple times by using isopyknic ethyl acetate, collecting an ethyl acetate phase, and drying to obtain the compound active component. The compound active component disclosed by the invention has the effects of inhibiting the activity of alpha-glucosidase, alpha-amylase and sucrase and improving sugar tolerance, and can be applied to preparation of medicines for preventing and treating diabetes mellitus.

The present invention relates to a method for converting sucrose comprised in a liquid food product into at least one fructooligosaccharide (FOS), the method comprising contacting said liquid food product with an Aspergillus niger fructosyltransferase under conditions allowing enzymatic conversion of sucrose to at least one FOS by said fructosyltransferase, wherein said contacting is performed at least until the sucrose concentration in said liquid food product is at most 15 g / L; and to compositions, uses, and products related thereto.

The invention discloses an amylosucrase mutant and application thereof in synthesis of rebaudioside M, and belongs to the technical field of enzyme engineering. According to the invention, a series of amylosucrase mutants are obtained by simultaneously mutating any one or more of the 211 site, the 279 site, the 319 site, the 377 site and the 433 site of the wild type amylosucrase from Kocuria sabuli, so that the catalytic activity of the amylosucrase is remarkably improved. Wherein the catalytic activity of a mutant obtained when the 211 site, the 279 site, the 319 site, the 377 site and the 433 site are mutated at the same time is the highest. When the amylosucrase mutant is used for producing rebaudioside M, the yield and the production efficiency of the amylosucrase mutant are obviously superior to those of wild type amylosucrase and other mutant enzymes. Therefore, the amylosucrase mutant provided by the invention has an important application value in the production of rebaudioside M.