17 results about "Dextranase" patented technology

The invention is applicable to the technical field of hydrogel, and provides dynamic cross-linked hydrogel and a preparation method and application thereof, and the preparation method comprises the following steps: cross-linking oxidized dextran and carboxymethyl chitosan containing phenylboronic acid modification groups; glucanase is added before the hydrogel is formed, and calcium peroxide nanoparticles coated with polydopamine are introduced; wherein the mass concentration of the oxidized dextran is 2-10% w / v, the mass concentration of the carboxymethyl chitosan containing the phenylboronic acid modified group is 2% w / v, the concentration of the glucanase is 10-100 U, and the concentration of the calcium peroxide nanoparticles coated with the polydopamine is 0.1-1% w / v. The hydrogel disclosed by the invention shows good cell compatibility, angiogenesis promoting capability and bioactivity for promoting dental pulp regeneration in multiple in-vitro and in-vivo experiments, is suitable for tissue engineering fields such as dental pulp injury repair and the like, and effectively solves the technical problem that conventional hydrogel is insufficient in cell survival support in three-dimensional culture and the like.

The invention discloses a marine bacterium dextranase mutant and application thereof, and relates to the technical field of biology. The gene sequence of the mutant is as shown in SEQ ID NO. 1. The content of isomaltohexaose in a product of the mutant is high. According to the invention, sodium ion binding sites F269 and D273 are obtained through molecular docking of AIphiFlod3, and corresponding alanine site-directed mutants F269A and D273A are respectively constructed. The alanine without charges is selected as a substitution residue, so that steric hindrance is reduced, and the path of substrate entry and product release is optimized. F269 sensitive to sodium ions is preferably selected for saturation mutation, the optimal mutant F269G is obtained, and the number of hydrogen bonds between the optimal mutant F269G and the sodium ions is increased from 2 to 3. The side chain of glycine is a hydrogen atom and is an amino acid with the smallest side chain, so that the path of substrate entry and product release is optimized, and meanwhile, the thermal stability of the mutant is improved. The main product of the mutant F269G for hydrolyzing dextran T70 is isomaltohexaose with high polymerization degree.

A high-purity yeast protein and a preparation method therefor, wherein the method comprises the following steps: inoculating an activated yeast strain into a liquid seed culture medium, culturing same in a shaker, then inoculating same into a fermentation culture medium for culturing, and centrifuging and washing same to obtain a yeast strain; preparing the yeast strain into a suspension solution, and performing a heat treatment to collect a precipitate; preparing the precipitate into a suspension, adding 5-50 U / mL of dextranase and 5-50 U / mL of cellulase at a pH of 5.0-7.0 and 30-60°C, and performing enzymatic hydrolysis to obtain a first enzymatic hydrolysate; adding a non-ionic solubilizer to the first enzymatic hydrolysate at a certain pH, and incubating the resulting mixure at a certain temperature to obtain a second enzymatic hydrolysate; and subjecting the second enzymatic hydrolysate to solid-liquid separation, washing and drying to obtain a high-purity yeast protein. The method reduces the possibility of protein denaturation. The final yeast protein product has a low dietary fiber content, a high branched-chain amino acid content and a high protein content, and exhibits good nutritional value and processing characteristics.

The invention discloses a high-activity dextranase preparation system and a high-activity dextranase preparation method. The high-activity dextranase preparation system comprises a fermentation device and a purification device, the fermentation device comprises a fermentation tank, a monitoring mechanism, a material supplementing mechanism, a continuous flow circulating mechanism, a microfluid impedance spectroscopy analysis mechanism and a control mechanism, the monitoring mechanism is connected to the fermentation tank, and the material supplementing mechanism is connected to the fermentation tank and used for supplementing liquid into the fermentation tank; the continuous flow circulating mechanism is connected between the bottom and the top of the fermentation tank so as to circularly process fermentation liquor in the fermentation tank, and the microfluid impedance spectroscopy analysis mechanism is connected to the continuous flow circulating mechanism so as to collect a metabolic flow characteristic frequency spectrum; the control mechanism can execute a self-adaptive pulse material supplementing algorithm according to the metabolic flow characteristic frequency spectrum and control the material supplementing mechanism to supplement materials, and the purification device performs purification treatment on fermentation products from the fermentation tank through a nine-time filtration purification process. The method improves the purity, improves the enzyme activity, improves the production efficiency, and reduces the cost.

The invention relates to an enzyme-containing oral care ointment composition, toothpaste and application. The enzyme-containing oral care ointment composition comprises the following components in percentage by mass: 0.4%-2% of an enzyme composition, 0.03%-0.3% of a cationic bactericide, 20%-80% of a humectant, 1.5%-5% of a foaming agent and 15%-75% of an abrasive, wherein the enzyme composition is prepared from dextranase and alpha-glucosidase; the humectant comprises polyethylene glycol, the average molecular weight of the polyethylene glycol is greater than or equal to 300g / mol, and the mass percent of the polyethylene glycol in the enzyme-containing oral care ointment composition is greater than or equal to 5%; the foaming agent comprises one or more of a nonionic surfactant and a zwitterionic surfactant; the friction agent comprises silicon dioxide. The enzyme-containing oral care ointment composition has the effect of inhibiting dental plaque, and can maintain the activity of enzyme for a long time.

The present invention aims to provide a liquid oral composition that does not contain ethyl alcohol and can sufficiently suppress the formation of precipitates during high-temperature storage. [Solution] The present invention provides a liquid oral composition that is substantially free of ethyl alcohol and comprises (A) component: dextranase and (B) component: xanthan gum, preferably further comprising (C) component. It is preferable that the content of component (A) is 0.0077 to 1.54% by mass, the content of component (B) is 0.01 to 1.0% by mass, and the mass ratio of the content of component (A) to the content of component (B) ((A) / (B)) is 0.6 to 150.

The application provides a blood-activating and stasis-removing medicinal composition containing fermented douchi and a preparation method thereof, belongs to the technical field of biological medicine, and the medicinal composition comprises fermented douchi, drynaria extract, extract of pereskia aculeata, tanshinone II A, notoginsenoside R1, ligustrazine, rhodioside, total flavones of hawthorn leaves and total flavones of mulberry leaves. The fermented douchi is prepared from soybeans and black beans through fermentation by bacillus subtilis and bacillus coagulans. The drynaria extract is prepared from drynaria powder through common enzymolysis by cellulase, chitinase and beta-glucanase, extraction by a two-phase solvent, and purification by a dextran gel column. The extract of pereskia aculeata is prepared from pereskia aculeata powder through common enzymolysis by pectinase, cellulase and xylanase, common enzymolysis by bromelain and subtilisin, and purification by a macroporous adsorption resin column. The medicinal components are prepared in a specific proportion to relieve blood stasis from two dimensions of "improving blood flow dynamics + preventing thrombus formation".

The invention relates to a tooth whitening preparation based on a compound enzyme synergistic effect and application thereof, and belongs to the field of tooth whitening preparations, the tooth whitening preparation comprises the following substances by weight: 15-20 parts of esterase, 15-25 parts of lipase, 10-15 parts of papain, 10-15 parts of dextranase, and 25-50 parts of maltodextrin. Based on the characteristic that the oral pigment has a'protein-lipid-polyphenol 'composite structure, a quaternary synergistic effect mechanism is provided, protein, lipid-soluble and polyphenol pigments can be removed, and safe and efficient whitening is achieved in the oral environment with the pH of 6.0-7.5; the lipase, the esterase and the papain cooperate with one another, so that pigment matrixes can be decomposed; the dextranase directly acts to decompose water-insoluble glucan, carbohydrate pigments are reduced, decomposition of dental plaque and pigments thereof is accelerated, the lipase, the esterase, the papain, the dextranase and the laccase do not damage teeth, and teeth are not damaged while tooth whitening is achieved.

The application belongs to the technical field of oral care, and discloses an anti-sugar composition containing hydrolyzed wheat protein and application thereof.The anti-sugar composition containing hydrolyzed wheat protein comprises the following components in mass fraction: 0.001-0.1 parts of glucose oxidase, 0.001-0.1 parts of dextranase, 0.001-10 parts of hydrolyzed wheat protein, 0.01-0.5 parts of arginine, 0.01-0.05 parts of fluoride and 0.001-0.1 parts of probiotics.The anti-sugar composition is prepared by scientific proportioning and synergistic effect, and the prepared oral care product can effectively decompose dental plaque, reduce dental plaque, inhibit the generation of bacteria, inhibit tooth demineralization and promote tooth remineralization, reduce the toxic and side effects of fluoride and maintain oral health.

The application belongs to the technical field of hydrogel and provides a dynamic cross-linking hydrogel and a preparation method and application thereof, and comprises the following steps: cross-linking oxidized dextran and carboxymethyl chitosan containing a phenylboronic acid modified group; adding dextranase before hydrogel formation, and introducing polydopamine-coated calcium peroxide nanoparticles; wherein the mass concentration of the oxidized dextran is 2-10% w / v, the mass concentration of the carboxymethyl chitosan containing the phenylboronic acid modified group is 2% w / v, the dextranase concentration is 10-100 U, and the concentration of the polydopamine-coated calcium peroxide nanoparticles is 0.1-1% w / v. The hydrogel of the application shows good cell compatibility, pro-angiogenic capacity and biological activity for promoting dental pulp regeneration in a plurality of in-vitro and in-vivo experiments, is suitable for the field of tissue engineering such as dental pulp injury repair, and effectively solves technical problems such as insufficient cell survival support of conventional hydrogels in three-dimensional culture.

This invention discloses a method for preparing recombinant dextranase from Chaetomium globosum and its uses. The amino acid sequence of the recombinant dextranase is shown in SEQ ID NO.2 or SEQ ID NO.4, and the nucleotide sequence of its encoding gene is shown in SEQ ID NO.1 or SEQ ID NO.3. The optimal pH of the recombinant dextranase is 4.5-7.0, and the optimal reaction temperature is 45-60℃. + K + and Ca 2+ It has an activating effect on enzyme activity, Mg 2+ NH4 + and Mn 2+ It had no significant effect on enzyme activity, Fe 3+ Zn 2+ Cu 2+ and Co 2+ It has an inhibitory effect on enzyme activity. Furthermore, this enzyme exhibits excellent pH stability, good thermal stability, and anti-interference ability, making it well-suited to the application requirements of the food, pharmaceutical, and chemical industries.

The present application relates to a kind of inhibiting dental plaque and composition of calculus, belong to oral care technical field.It contains composite plant fermentation extract, immobilized lysozyme, immobilized glucose oxidase, dextranase, chelating agent and oral acceptable carrier according to certain mass fraction;Composite plant fermentation extract is made by being fermented by specific concentration lactobacillus plantarum after being mixed by salvia miltiorrhiza and rhodiola rosea powder according to 3-5:1.The composition is synergized by composite plant fermentation extract and immobilized enzyme preparation, chelating agent, not only improves the storage stability and action efficiency of enzyme, realizes the source inhibition of dental plaque formation and the hindering of calculus mineralization, but also has additional functions such as oral mucosa protection, anti-inflammatory, solves the problem of single function, insufficient stability, low active ingredient utilization rate of existing product, and can be used for preparing toothpaste, mouthwash and other oral care products.

This invention provides a marine-derived glycomonad K1 strain, a method for producing dextran anhydrase, and its applications. The strain is a Gram-positive actinomycete. Colonies on a solid culture medium containing blue dextran exhibit the following characteristics: initially smooth surface, turning into a white, dry powder after three days of incubation; dried, with radially arranged edges; white on the front and black and opaque on the back. This invention also provides a method for producing dextran anhydrase using the aforementioned glycomonad K1 strain. The dextran anhydrase prepared using this method exhibits good thermal stability and strong pH tolerance, and can be widely used in the sugar, food, pharmaceutical, health, daily necessities, and chemical industries.

The invention discloses a dextranase and glucose oxidase compound composition and application thereof in preventing and treating plant diseases, and belongs to the technical field of agricultural biology. Effective components of the compound composition are glucanase and glucose oxidase, and the active unit ratio of the glucanase to the glucose oxidase is (10: 1)-(1: 2). The composition can be applied in a foliar spraying or root irrigation mode and is used for preventing and treating powdery mildew, gray mold, downy mildew and canker of plants. The composition disclosed by the invention realizes synergistic interaction through combination of direct decomposition of enzyme and induction of plants to generate systematic resistance, has a control effect obviously superior to that of a single enzyme preparation, has the advantages of safety, environmental protection, difficulty in generating drug resistance and the like, and is suitable for green and organic agricultural production.

The invention relates to the field of dextran production, and particularly discloses a process optimization method for producing dextran from beet, which comprises the following steps: pretreating beet juice by pectinase to obtain a high-purity substrate, innovatively adopting a dextransucrase and alpha-1, 3 branching enzyme compound catalytic system, and combining with a Mn < 2 + > cofactor and a Tween 80 stabilizer to improve the enzyme activity efficiency, thereby obtaining the high-purity dextran. The molecular weight distribution is regulated and controlled in real time through endoglucanase, and a multi-stage ethanol precipitation and purification process is matched, so that the purity of the product reaches 98% or above and PDIlt; 1.25, resource utilization of single-cell protein produced by waste liquid fermentation is originally realized, and the sucrose conversion rate of the whole process is gt; the recovery rate of dextran is greater than or equal to 85%. Compared with a traditional method, the method has the advantages of being low in raw material cost, high in molecular weight controllability, environmentally friendly and the like, and is suitable for industrial production of pharmaceutical-grade dextran.

The present invention aims to provide a liquid oral composition that contains no ethyl alcohol and in which the generation of precipitates during storage at high temperatures can be sufficiently suppressed. Specifically, the present invention provides a liquid oral composition that is substantially free of ethyl alcohol, and comprises dextranase as a component (A), and xanthan gum as a component (B), and preferably further comprises a component (C). It is preferable that at least one of the following conditions is satisfied: the content of component (A) is 0.0077 to 1.54% by mass; the content of component (B) is 0.01 to 1.0% by mass; and the mass ratio ((A) / (B)) of the content of component (A) to the content of component (B) is 0.6 to 150.

This invention belongs to the field of biotechnology and discloses a method for immunofluorescence staining of proteins in Lycoris radiata meiotic cells. The method includes the following steps: 1) treating fixed anthers to obtain pollen mother cells in the meiotic stage; 2) treating with enzymes to decompose the cytoplasm of the meiotic cells; 3) preparing slides and performing fluorescent staining on the treated meiotic cells; 4) observing the localization signal of the target protein under a fluorescence microscope. This invention uses dextranase and other enzymes to treat pollen mother cells, effectively decomposing the thick outer callosity protective layer of Lycoris radiata pollen mother cells, which is beneficial for antibody binding to chromosomes; at the same time, it improves the slide preparation method, effectively enhancing the expression of fluorescence signals. This method is of great significance for studying the subcellular localization of proteins with different functions in Lycoris radiata pollen mother cells in the meiotic stage using immunofluorescence localization technology.