31 results about "Alkaline proteinase" patented technology

The application provides a mung bean protein salty taste enhancing peptide, a screening and preparation method and application. The method comprises the following steps: step 1, carrying out step-by-step enzymolysis on mung bean protein by using alkaline protease and flavor protease, carrying out ultrafiltration grading, and screening an initial extract of the salty taste enhancing peptide by using an electronic tongue; step 2, further identifying polypeptide sequences by using LC-MS / MS; and step 3, screening polypeptides with strong interaction capability with salty taste receptors TMC4 and ENaC by combining biological activity prediction, target active fragment screening, safety and physicochemical property evaluation and molecular docking analysis. The salty taste enhancing peptide of the mung bean protein obtained by screening comprises polypeptides represented by RPFF, APDLRGY, WDDIGGL, FDGF and AEFF, and contains RP, RG, DD, DGF and FF characteristic peptide segments, respectively. The polypeptides are synthesized by using a solid phase, and the salty taste enhancing effect of the polypeptides is verified by using an electronic tongue. When 0.03% of the above synthesized polypeptides are added to a 0.4% NaCl solution, the salty taste enhancing rates are 90%, 62%, 34%, 52% and 42%, respectively. The polypeptides can significantly enhance salty taste perception of a solution under low-salt conditions, and achieve the effect of salt reduction without taste reduction.

This application belongs to the field of biotechnology, specifically relating to giant salamander skin collagen peptides, their preparation methods, and applications. This application provides a method for preparing giant salamander skin collagen peptides. The method first pre-treats the fish skin, then performs ultrasonic-assisted extraction under acidic conditions to effectively promote collagen dissolution. The extract undergoes flocculation to remove impurities, significantly reducing interference from other proteins. The enzymatic hydrolysis stage employs a stepwise enzymatic hydrolysis strategy: first, a combination of alkaline protease and another specific protease is used for hydrolysis, sequentially cleaving the complex structure of giant salamander skin collagen to improve initial hydrolysis efficiency and generate specific intermediate peptides; subsequently, a flavor protease is added for further deep hydrolysis to achieve complete hydrolysis. This method has high enzymatic hydrolysis efficiency, controllable hydrolysis degree, concentrated molecular weight distribution of the obtained collagen peptides, high yield of the target product, and stable process.

The application discloses a preparation method of sturgeon peptide and application of the sturgeon peptide in improving immunity and sexual function. The method comprises the following steps: S1, one or more of sturgeon cartilage, fish bone and fish skin are crushed after being thawed, and pure water is added according to a material-liquid ratio of 1:3-1:4 and is pumped into an enzyme hydrolysis tank; S2, the enzyme hydrolysis tank is heated to 85-90 DEG C under the condition of a closed low pressure of 0.06-0.08 MPa, and protein is denatured for 15-20 min; S3, the temperature is reduced to 60-65 DEG C, the pH is adjusted to 8.0-8.5, 2‰-3‰ alkaline protease of the raw material amount is added, and constant-temperature enzyme hydrolysis is carried out for 170-190 min; the temperature is increased to 85-90 DEG C after the enzyme hydrolysis is completed, and the enzyme is inactivated for 14-16 min; S4, decolorization is carried out; S5, filtration and concentration are carried out; S6, vacuum concentration is carried out; S7, sterilization and drying are carried out, and sturgeon peptide finished products are obtained. The sturgeon peptide obtained by the preparation method has small molecular weight and high active ingredients.

This invention relates to the field of microbial culture medium raw material technology, specifically to a method for preparing white fish peptone. This invention effectively removes odor precursors and pigment impurities through the synergistic effect of raw material brine rinsing, low-temperature quick-freezing, and a specially formulated compound sedimentation agent. The resulting product is light in color, almost odorless, and has excellent water solubility, significantly improving its application adaptability. This invention employs a dual-enzyme stepwise hydrolysis process using alkaline and neutral proteases, combined with low-temperature concentration and drying technology throughout the process, avoiding heat damage and Maillard reactions. The product has high total nitrogen and amino nitrogen content, a uniform amino acid profile, and retains the nutritional activity and bioavailability of white fish protein to the greatest extent. The unique compound sedimentation technology of this invention significantly improves solid-liquid separation efficiency, effectively protects the subsequent ceramic membrane filtration system, reduces the risk of membrane clogging and maintenance costs, and, combined with a gradient vacuum falling membrane concentration process, achieves low-energy, high-yield continuous production.

The application discloses an active peptide for promoting bone growth, and a preparation method and application thereof. The active peptide contains amino acid sequences GPAGPLGPV, LGVPLPL, FLPEPPQEE and SFLPEPPQE, and is derived from an enzymatic product of animal bone collagen. The average molecular weight of the enzymatic product is 500-1000 Da, and the mass percentage of components with a molecular weight less than 1000 Da is greater than 60%. The preparation method comprises the following steps: sequentially performing acid treatment, alkali treatment, extraction, filtration and ion exchange on animal bone, and then performing enzymolysis on the animal bone under the action of a protease to obtain an enzymolysis solution, wherein the protease is selected from alkaline protease, trypsin and papain; and the enzymolysis solution is separated and purified, wherein the separation and purification comprises ultrafiltration membrane grading and chromatographic separation, the cut-off molecular weight of the ultrafiltration membrane is 3kDa, and the chromatographic separation comprises gel chromatography and reverse-phase high performance liquid chromatography separation. The low-molecular active peptide obtained by the application can promote the proliferation and / or differentiation of osteoblasts, improve the alkaline phosphatase activity, has a small molecular weight and is easy to be absorbed and utilized by the body, has a wide raw material source, has a simple and controllable preparation process, and has a good application prospect.

This invention discloses a method for preparing Ganoderma lucidum polypeptides, belonging to the field of biotechnology. Addressing the problems of incomplete cell wall disruption, low enzymatic hydrolysis efficiency, and low polypeptide yield in existing Ganoderma lucidum polypeptide preparation processes, this invention employs ultrasound-assisted compound enzymatic hydrolysis combined with freeze-drying technology to achieve efficient preparation. Using dried Ganoderma lucidum fruiting bodies as raw material, the product is pretreated to obtain ultrafine powder. Cell walls are disrupted through intermittent ultrasonic pretreatment with specific material-to-liquid ratios and ultrasonic parameters. Then, a compound enzyme consisting of alkaline and neutral proteases is used for synergistic enzymatic hydrolysis. Following enzyme inactivation centrifugation, microporous membrane purification, vacuum concentration, and vacuum freeze-drying, Ganoderma lucidum polypeptide powder is finally obtained. The process conditions of this invention are mild and environmentally friendly, significantly improving protein dissolution rate and enzymatic hydrolysis efficiency. The obtained Ganoderma lucidum polypeptides contain at least 85% small molecule peptides (molecular weight ≤3000 Da), resulting in a significantly improved polypeptide yield while fully preserving polypeptide bioactivity. The product has high purity and good solubility, making it suitable for industrial-scale production and applicable to a wide range of food, health product, and pharmaceutical fields.

The application discloses a pea peptide mixture with calcium binding and osteogenesis promoting effects and application thereof, wherein the pea peptide mixture is derived from protein components in a by-product of pea starch extraction, is obtained through alkaline protease and papain enzymolysis and separation and purification, and is rich in aspartic acid and glutamic acid residues. The pea peptide mixture can effectively bind with calcium ions, the pea peptide mixture can promote calcium ion delivery in osteoblasts, improve alkaline phosphatase activity, and promote osteoblast differentiation, the osteogenesis promoting effect of the pea peptide mixture is related to epidermal growth factor receptor EGFR and downstream PI3K-Akt signal pathway regulation. The pea peptide mixture can improve glucocorticoid-induced zebrafish bone mass reduction, and up-regulate mRNA expression levels of ALP, EGFR, PI3K and Akt and other genes related to osteogenesis. The pea peptide mixture has both functions and nutrition, can be used for preparing products for promoting osteogenesis, improving bone mass, improving bone mass reduction and assisting in improving osteoporosis, and has a wide application prospect in the field of bone health.

This invention provides a sea buckthorn seed protein peptide, its preparation method, and its application, relating to the field of plant protein peptide extraction technology. The preparation method includes: pulverizing defatted sea buckthorn seed residue, performing ultrasonic-assisted extraction, adjusting the pH value to precipitate, and centrifuging to obtain a protein extract; adding a complex protease composed of alkaline protease, flavor protease, and neutral protease in a specific enzyme activity ratio for targeted enzymatic hydrolysis; purifying the hydrolysate sequentially through a 3kDa ultrafiltration membrane and a 1kDa nanofiltration membrane, collecting the permeate; adding an encapsulating agent and spray drying to obtain the final product. The sea buckthorn seed protein peptide prepared by this method has a molecular weight of less than 3kDa (≥85%), a purity of ≥90%, and exhibits excellent DPPH free radical scavenging ability and angiotensin-converting enzyme inhibitory activity. This invention achieves efficient extraction of sea buckthorn seed protein and targeted enrichment of active peptides. The product can be used as a functional food, health product, or pharmaceutical raw material for antioxidation and blood pressure reduction.

This invention belongs to the field of protein technology and relates to a peptide that prevents collagen loss and its preparation method. The amino acid sequence of the peptide is KSYELPDGQVITIG, with the key active fragment being ELPDGQVIT. The peptide is obtained by enzymatic hydrolysis of defatted grain insect powder using alkaline protease, trypsin, papain, neutral protease, and flavor protease. This peptide can inhibit the expression of MMP1 and MMP9 in L929 cells after UVA irradiation, thus alleviating collagen loss.

This invention discloses a Hu sheep active peptide complex and its application in bone health care. Using healthy Hu sheep bones as raw material, collagen is extracted after defatting and decalcification. This collagen is then enzymatically hydrolyzed with trypsin and alkaline protease, followed by ultrafiltration, desalting, and freeze-drying to obtain Hu sheep bone collagen peptides. These collagen peptides are mixed with pharmaceutical excipients, calcium source compounds, chondroprotective agents, and fat-soluble vitamins. An ethanol-water binder solution containing palmitoyl aspartate diethyl ester and hesperidin-3-O-glucoside is added, and the mixture is granulated, dried, sized, and pressed to obtain the active peptide complex. This complex, through the synergistic effect of its components, can significantly promote osteoblast proliferation and inhibit apoptosis, effectively increasing bone density in osteoporosis model animals. It also exhibits excellent biocompatibility and no cytotoxicity, solving the problems of limited function, insufficient preparation efficiency, and instability of existing single active peptides. This makes it suitable for the development and application of bone health-related nutritional supplements.

The application discloses a method for reducing the allergenicity of tenebrio molitor by ultrasonic and enzymatic hydrolysis, and relates to the technical field of food processing and food safety. First, the tenebrio molitor protein is extracted by an alkali solution method, and then the tenebrio molitor protein solution is treated by ultrasonic and enzymatic hydrolysis to change the conformational epitope and linear epitope of the tenebrio molitor protein, and finally, the treated tenebrio molitor protein solution is freeze-dried to obtain tenebrio molitor protein powder with low allergenicity. The ultrasonic cavitation effect and the specific hydrolysis of enzymatic hydrolysis are used to produce a synergistic effect, and under the combined treatment of 300 W ultrasonic power and alkaline protease, the allergenicity reduction rate can reach more than 70%, which is significantly better than single processing mode, and provides technical support for the development of tenebrio molitor low allergenic food.

The application belongs to the field of food, and particularly relates to a yeast enzymatic hydrolysate with high emulsification performance, a yeast protein, a yeast protein sodium salt product, and preparation and application thereof. The emulsification activity of the yeast enzymatic hydrolysate is greater than or equal to 25.0 m2 / g, and the emulsification stability is greater than or equal to 77.0%; the emulsification activity of the yeast protein is greater than or equal to 70.0 m2 / g, and the emulsification stability is greater than or equal to 175.0%; the emulsification activity of the yeast protein is greater than or equal to 70.0 m2 / g, and the emulsification stability is greater than or equal to 175.0%. In the application, the yeast is subjected to complex enzymolysis by alkaline protease, flavour protease, glucanase, mannanase and glutamine transaminase, and then subjected to ionization reaction with sodium hydroxide to obtain a yeast protein sodium salt product. The yeast protein sodium salt product has high emulsification activity, good color and flavor, and can be used as a natural emulsifier, thereby solving the problems of limited production of sodium caseinate, unstable supply and high price.

This invention discloses an earthworm protein peptide with in vitro thrombin-inhibiting activity and its preparation method, belonging to the field of functional food technology. The method first pre-treats earthworm raw materials to obtain earthworm protein; then, it uses pepsin and alkaline protease for stepwise enzymatic hydrolysis under varying temperature and pH, and ultrafiltration to collect short peptide solutions with a molecular weight below 3 kDa; the short peptide solution is specifically captured using an affinity chromatography material coupled with bovine thrombin, followed by elution, nanofiltration desalting concentration, and spray drying to obtain the final product. This invention fully releases the peptides through a dual enzymatic hydrolysis process and utilizes thrombin affinity chromatography to directionally enrich peptides with specific inhibitory activity, effectively solving the problems of low content and poor targeting of active ingredients in earthworm protein peptides in existing technologies, and significantly improving the purity and in vitro anticoagulant activity of the product.

The application discloses a preparation method of instant potato polypeptide powder and belongs to the field of food protein processing. The method comprises the following steps: dispersing potato crude protein powder in deionized water, stirring, adjusting pH to 9-10, heating and dissolving, collecting supernatant, adjusting pH to 4.5-5.5, centrifuging, washing, adjusting pH to 6.5-7.5, and drying to obtain purified potato protein powder; adding the potato protein powder into deionized water, adding alkaline protease into the dispersion liquid to hydrolyze; heating the reaction system to 80-90 DEG C to inactivate the alkaline protease, and removing impurities by centrifugation; collecting polypeptide liquid with a molecular weight less than 10 KD; precipitating the polypeptide liquid by adopting a pH gradient precipitation method; resuspending and washing the precipitate with deionized water; homogenizing, heating to 45-55 DEG C, and spray drying. The instant potato polypeptide powder is obtained by adopting the alkali dissolution and acid precipitation method combined with the enzymolysis method, and the instant potato polypeptide powder with a purity of 90%-95% is obtained.

The present application relates to the field of biological medicine and functional food, and discloses a kind of nutrition composition based on marine shrimp peptide for anti-obesity and improving metabolic syndrome;Including: Chinese tube whip shrimp peptide active component and pharmaceutically acceptable adjuvant, the Chinese tube whip shrimp meat protein is used as raw material, and the Chinese tube whip shrimp meat protein is prepared by alkaline protease enzymolysis, and the Chinese tube whip shrimp meat protein contains peptide segment with molecular weight less than 1 kDa, and APPPPP, HPPPP and MPLPP can be detected.The pharmaceutical composition can reduce the weight and fat tissue weight under the state of obesity, improve dyslipidemia, abnormal liver function and liver steatosis, reduce oxidative stress level, improve intestinal mucosal barrier damage and intestinal permeability increase, and regulate intestinal flora structure change.The active component in the present application is clear in origin, and the preparation process is clear, has the synergistic effect from lipid metabolism regulation, liver protection to intestinal barrier improvement, and can be used for preparing medicine for preventing or treating obesity and improving metabolic syndrome.

The application belongs to the technical field of biological products and health products processing, and provides a method for co-production of bovine bone essence, bovine bone oil and collagen peptide by using bovine bone. The method of the application can realize high-efficiency co-production of bovine bone essence, bovine bone oil and collagen peptide by using only alkaline protease in the enzymolysis process through horizontal stirring extraction, thereby saving energy and resources, simplifying the process flow, and improving the utilization rate of bovine bone and the product yield.

The application discloses egg white protein source small molecule peptides with the functions of regulating immunity and tonifying qi and blood and application thereof, and belongs to the technical field of small molecule peptides. The application uses alkaline protease, papain and neutral protease to sequentially perform enzymolysis on egg white protein to obtain egg white small molecule peptides containing dipeptide LW. Animal model function verification shows that the dipeptide LW and the egg white small molecule peptides containing the peptide segment have the function of improving qi and blood deficiency, and high-dose (converted into 3.0g / 60kg.d for an adult) egg white small molecule peptides increase red blood cells, hemoglobin, platelets and lymphocytes by 16.6%, 14.7%, 23.4% and 28.75% respectively. Food-derived bioactive peptides have high biological safety, and therefore, the dipeptide LW and the egg white small molecule peptides containing the peptide segment can be applied to the preparation of medicines with the functions of regulating immunity and improving qi and blood, and have good market prospects and application potential.

Enzymatic Preparation and Immunological Application of Small Molecule Turtle Peptides. The method for preparing turtle peptides includes: providing turtle protein raw materials; performing a primary enzymatic hydrolysis of the turtle protein raw materials using an alkaline protease; performing a secondary enzymatic hydrolysis of the primary hydrolysis product using a complex enzyme containing flavor protease and trypsin; and inactivating, separating, and purifying the secondary hydrolysis product to obtain turtle peptides. This invention efficiently degrades large molecule turtle protein into small peptides and oligopeptides with an average molecular weight of less than 1000 Da, especially 180-800 Da, through stepwise synergistic enzymatic hydrolysis. These small peptides can be directly and completely absorbed through the intestinal peptide transport system, with an absorption rate and efficiency far exceeding that of free amino acids and whole proteins, significantly improving bioavailability. The small molecule turtle peptides prepared by this invention can significantly enhance the phagocytic capacity of macrophages and promote the proliferation and differentiation of lymphocytes, thereby enhancing the body's immune function at both the innate and adaptive immune levels.

The application discloses a preparation method of a fat-flavor starch milk carbohydrate-based gel and relates to the technical field of starch lipid-structured gel processing. The method comprises the following steps: S1, taking rice protein in rice milk powder as raw material, adding deionized water according to a material-liquid ratio of 1:5-10, adjusting pH to 6.5-8.0, adding a compound protease, the enzyme addition amount being 0.5%-2.0% of the mass of the protein, carrying out enzymolysis at 50-55 DEG C for 4-8 hours, raising the temperature to 90 DEG C to inactivate the enzyme for 15 minutes after the enzymolysis is completed, and centrifuging to obtain an enzymolysis peptide mixture by taking the supernatant; the method is characterized in that the specific proportion of alkaline protease and flavor protease is adopted to compoundly hydrolyze the rice protein, the enzymolysis liquid rich in hydrophobic amino acid residue exposed peptide segments is obtained, the rice starch is hydrolyzed by steps to obtain a sugar syrup with moderate viscosity and a reducing end group, the precise matching of the peptide segments and sugar molecules is realized, and a short-time flash evaporation process is adopted.

This invention belongs to the field of enzyme engineering technology and discloses a thermostable alkaline protease mutant and its application in the degradation of zein. The thermostable alkaline protease mutant was obtained by site-directed mutagenesis screening of the alkaline protease gene hapR from *Bacillus belysae*. The alanine at position 122 of HapR was mutated to lysine, and the asparagine at position 132 was mutated to glycine. Compared with the wild-type alkaline protease HapR, the enzyme activity of the alkaline protease mutant was increased by 1.18 times. The half-life of this mutant at 60°C reached 30.03 min, and its thermostableness was improved by 1.65 times compared to the wild type, significantly enhancing its ability to degrade zein.

The application discloses a preparation method of high-purity sponge bone needles and application of the high-purity sponge bone needles in penetration promotion, and belongs to the technical field of sponge bone needles. The method comprises the following steps: cutting natural sponges, soaking the sponges in deionized water and performing ultrasonic oscillation, filtering, and cleaning to obtain pretreated sponges; subjecting the pretreated sponges to alkaline protease enzymolysis to obtain primary enzymolysis products; subjecting the primary enzymolysis products to ginger protease enzymolysis to obtain secondary enzymolysis products; and performing vacuum freeze-drying to obtain the high-purity sponge bone needles; the natural sponges are subjected to enzymolysis treatment by alkaline protease and ginger protease to obtain the high-purity sponge bone needles; and the sponge bone needles are used in surface grafting of wheat oligopeptides and loading of giant salamander skin collagen, pomegranate seed extract, Honeysuckle extract, Gotu Kola extract, early celery extract, iris extract, oyster shell extract and calcium chloride mixed treatment materials, so that the repair effect on skin inflammation acne is improved.

The application discloses application of a large-mouth black bass stomach polypeptide in preparation of an antioxidant and / or immunoregulation product, relates to the field of bioactive peptides, and is characterized in that the large-mouth black bass stomach polypeptide is a polypeptide product obtained by alkaline protease enzymolysis of large-mouth black bass stomach, and components with molecular weights less than 3000 Da account for more than 98% of the total peptide amount. The polypeptide has significant DPPH free radical, hydroxyl free radical and ABTS cationic free radical scavenging capacity and reducing capacity, can promote macrophage proliferation, enhance phagocytosis, promote nitric oxide secretion, up-regulate immune-related cytokine expression, and play an immunoregulation role through activation of P38 and P44 MAPK signal pathways. The application realizes high-value utilization of large-mouth black bass processing by-products, has high product safety, and has a wide application prospect.

This invention discloses an alkaline protease mutant and its application in the preparation of active hippocampal peptides. This alkaline protease mutant exhibits high enzyme activity and high thermal stability, with an optimal operating temperature of 60°C. Even after treatment at 70°C for 90 minutes, it retains 23.45% of its relative enzyme activity, demonstrating excellent thermal stability. When used for the enzymatic hydrolysis of defatted hippocampal powder, it can increase the yield of active hippocampal peptides from 11.7% to 82.4%, and improve the antioxidant activity (IC50) of the hydrolysate. 50 The enzyme activity was increased by approximately 51.4%, effectively solving the bottleneck of the difficulty in synergistically improving enzyme activity and thermal stability in existing technologies. This provides an excellent catalyst and process solution for the industrial-scale, efficient, and low-cost production of hippocampal active peptides.

This invention discloses a high-yield, dual-effect earthworm protein small molecule peptide and its preparation method, specifically relating to the field of biomedical technology. The preparation method includes: S1, synergistic enzymatic hydrolysis: earthworm protein undergoes autolysis, followed by enzymatic hydrolysis with a complex enzyme of flavor protease and alkaline protease; S2, charge-size bi-stage membrane separation: the hydrolysate is sequentially passed through a 5kDa first-stage ultrafiltration membrane and a 1kDa second-stage ultrafiltration membrane modified with a positive charge; S3, dual-activity-guided purification: using anticoagulant activity and dipeptidyl peptidase-IV inhibitory activity as tracking indicators, the highly active components are collected. The small molecule peptide obtained by this invention has a molecular weight of 400-800 Da, contains novel sequences shown in SEQ ID NO:1 and SEQ ID NO:2, and simultaneously possesses anticoagulant activity and DPP-IV inhibitory activity, with a yield of 17.2-19.1%, which is more than 30% higher than conventional methods. The process of this invention is stable and has good prospects for industrialization.

This application relates to the field of bioactive peptide preparation technology, and discloses a method for preparing a blood pressure-lowering protein active peptide composition. The raw materials for this composition include a protein substrate, deionized water, alkaline protease, a complex solubilizing buffer, and a cross-linked aqueous solution containing sodium hexametaphosphate. The preparation method includes: isothermal enzymatic hydrolysis of the protein substrate; adding the complex solubilizing buffer to the hydrolysate and instantaneously heating it to construct a steric hindrance protective layer for the short peptides; subsequently injecting the cross-linked aqueous solution for high-shear cross-linking, allowing large molecular impurities to target and bind; and then directly spraying it into a vacuum flash evaporator for rapid cooling, causing the cross-linked protein network to shrink and densify; finally, centrifugation, ultrafiltration, concentration, and drying are performed to obtain the finished product. This invention prevents the active short peptides from co-precipitating with impurities under heat, effectively maintaining the blood pressure-lowering activity of the peptides, and densifying the impurity flocs, thereby improving the separation and sludge removal efficiency and the anti-fouling ability of the ultrafiltration membrane.

The application discloses a method for preparing yeast by using corn starch sugar residue as a nitrogen source. The method comprises the following steps: firstly, dissolving corn starch sugar residue, adding appropriate amounts of K2HPO4, KH2PO4 and MgSO4, adjusting pH to 8.5-10.5, high-pressure homogenization treatment, preparing a sugar residue solution, adding alkaline protease, and performing enzymolysis reaction; after the enzymolysis is completed, supplementing glucose and performing high-temperature and high-pressure sterilization; inoculating activated yeast, and performing culture; after reaching the stable period, performing centrifugation, collecting and washing the precipitate, and preparing fresh yeast. The method uses a by-product of a corn starch sugar industry as a raw material, utilizes the physical action of homogenization and the biochemical action of enzymolysis, dissociates the protein supramolecular structure of the hydrophobic denatured aggregated and condensed state in the sugar residue, performs enzymolysis on the protein, uses the enzymolysis liquid as an organic nutrient nitrogen source element, utilizes the sugar carried by the sugar residue, supplements appropriate amounts of glucose carbon source, and then performs yeast culture, propagation and preparation.

This invention discloses a collagen peptide and its preparation method, as well as conditioning agents and cosmetics. The method involves sequentially treating animal-derived tissue with lipase and alkaline protease. During alkaline protease treatment, sodium alginate and carboxymethyl chitosan in a mass ratio of (0.1-0.3):(0.05-0.1) are added to the system to form a "micro-compartment" further encapsulating the enzymatic hydrolysate for continued hydrolysis. Then, enzyme inactivation and solid-liquid separation are performed, and the clear liquid is collected and freeze-dried to prepare the collagen peptide. This preparation method efficiently extracts collagen peptides with high dipeptide content from animal-derived tissues, thereby improving the cell proliferation and migration activity of the collagen peptides. It has excellent barrier repair activity and can be widely used in conditioning agents and cosmetics.

The application belongs to the technical field of enzyme engineering and feed processing, and particularly relates to a basic protease mutant AprBcpM and application thereof. The application first takes basic protease BCP as a starting template, increases a disulfide bond in a flexible region of the three-dimensional structure of BCP, and obtains the mutant AprBcpM with improved thermal stability. Compared with the starting template BCP, the residual enzyme activity of the mutant AprBcpM after heat treatment at 55 DEG C, 60 DEG C and 65 DEG C for 30 minutes is 3.58 times, 6.26 times and 8.09 times that of the starting template BCP, respectively. In addition, after enzymolysis reaction of the mutant AprBcpM at 50 DEG C for 120 minutes, the acid-soluble protein content produced by hydrolysis of cottonseed protein is 48.9%, which is 2.27 times that of the starting template BCP. Therefore, the prepared protease mutant has good thermal stability and high enzyme activity, and can be used for preparing a cottonseed protein enzymolysis product.

The application belongs to the field of biological fertilizer, and particularly relates to a preparation method of a double biological protein mixture fertilizer and application thereof. The method is prepared by mixing fish and earthworm tissues, and then performing one-step synergistic enzymolysis by using a complex enzyme system containing alkaline protease, flavor protease, chitinase, lipase and trypsin, and then performing enzyme inactivation and filtration. The process can efficiently degrade chitin, and significantly improve the content of small molecule peptides and antioxidant activity in the product. The obtained fertilizer can effectively promote crop growth, enhance stress resistance and improve soil, and can improve potato yield and reduce disease incidence in saline-alkali land planting.