198 results about "Papain" patented technology

The invention discloses a preparation method of micromolecular active collagen peptide, which comprises the following steps: (1) cutting fresh leather into fragments, pretreating the leather with a sodium bicarbonate solution, rinsing the leather with deionized water, and refrigerating and storing; (2) mixing papain, bromelain, pancreatin, pepsase, alkaline protease, neutral protease and flavourzyme to obtain a compound enzyme preparation; (3) performing high-pressure steam sterilization on the leather at 110-140 kPa and 120-122 DEG C to obtain leather with the hydrolysis degree of 75-85%, then adding distilled water into the leather to obtain mucilage, then adding a compound enzyme preparation into the mucilage, reacting for 5.5-6.5 hours at the pH of 6.8-7.2 and the temperature of 50-55 DEG C, and then performing enzyme inactivation at the temperature of 85-95 DEG C; and (4) after the reaction system is cooled to room temperature, purifying and centrifuging the reaction system, and taking clarified supernate, thereby obtaining the product. Different animal skins are treated, the proportion of peptide fragments with the molecular weight smaller than 1000 Da of the prepared small-molecule active collagen peptide is larger than or equal to 80%, and the hydroxyproline content is larger than 3%.

The invention relates to the technical field of cosmetics, and particularly discloses emulsion type foaming cleaning scrub cream with a skin care effect and a preparation method of the emulsion type foaming cleaning scrub cream. The scrub cream is prepared from the following raw material components in percentage by mass: 8 to 15 percent of glycerol, 0.2 to 0.9 percent of sodium hydroxide, 0.3 to 0.8 percent of citric acid, 0.03 to 0.2 percent of EDTA (Ethylene Diamine Tetraacetic Acid) disodium, 0.5 to 1.5 percent of an auxiliary agent, 1.5 to 3.0 percent of a thickening agent A, 1.5 to 3.0 percent of a thickening agent B, 5.86 to 1457 percent of an emollient, 12 to 22 percent of a surface active foaming agent, 0.8 to 3.0 percent of an emulsifying agent, 2.5 to 13 percent of a cutin stripping agent, 0.7 to 1.3 percent of a preservative, 0.32 to 0.92 percent of a skin conditioning agent and the balance of water, the skin conditioner is a mixture prepared from sodium hyaluronate, tocopherol, papain, nicotinamide, carnosine, panthenol and phytosterol oleate.

The invention discloses giant salamander grease and application thereof in a blood fat reducing product. The giant salamander grease is obtained by adding papain into giant salamander tissues for enzymolysis and then adsorbing by using an egg white modified microsphere adsorbent. The giant salamander grease is refined by using the egg white modified microsphere adsorbent, and then the giant salamander grease is compounded with the dark tea extract, the hawthorn extract and the lotus leaf extract and processed into embedded particles, so that the water solubility of the giant salamander grease preparation can be improved, and the giant salamander grease preparation can be used as an oral preparation for reducing blood fat.

The invention discloses a preparation method of composite active peptide with anti-wrinkle, whitening and freckle-removing effects from marine fish byproducts, cod byproducts, namely fish heads, fish bones and fish skins, are used as raw materials and are mixed according to the mass ratio of 3: 3: 4, and the composite active peptide is prepared through the steps of pretreatment, enzymolysis, enzyme deactivation, centrifugal separation and purification. A compound enzyme used in the enzymolysis step is composed of trypsin and papain according to a certain proportion, and the enzyme addition amount, the enzymolysis time, the enzymolysis temperature and other conditions are optimized. The prepared composite active peptide with the anti-wrinkle, whitening and freckle-removing effects from the marine fish by-product has good anti-wrinkle, whitening and freckle-removing effects, resource utilization of the cod by-product is achieved, and the composite active peptide has high application value.

The invention relates to a method for extracting genome DNA of plants rich in secondary metabolites and a buffer solution, and belongs to the technical field of molecular biology and botany. The method solves the technical problems of low DNA extraction efficiency, poor purity, easy degradation and the like when a traditional DNA extraction method is used for treating plant tissues rich in secondary metabolites such as alkaloid, polyphenol and the like. Comprising the following steps: adding a complexing agent such as polyethylene glycol or polyvinylpyrrolidone when grinding plant tissues in a liquid nitrogen environment; splitting by using a cell wall splitting buffer solution containing dithiothreitol and a nonionic surfactant; carrying out DNA release and extraction at 60-70 DEG C by adopting a CTAB (Cetyltrimethyl Ammonium Bromide) extraction buffer solution containing polyethylene glycol and papain; and then purifying and precipitating to obtain high-purity genome DNA (Deoxyribose Nucleic Acid). The method can effectively remove alkaloid, protein and other impurities, significantly improves the DNA yield and purity, and is suitable for genome sequencing, genetic resource protection, medicinal plant molecular identification and the like of plants with high secondary metabolites such as Stephania kwangsiensis and the like.

The invention relates to the technical field of food biology, and discloses an antiviral cubilose polysaccharide active component enriched with bound sialic acid as well as a preparation method and application of the antiviral cubilose polysaccharide active component. The weight-average molecular weight of the cubilose polysaccharide active component is 30-36 kDa, the molecular weight distribution coefficient is 1.1-1.2, the content of bound sialic acid is greater than or equal to 24.0%, and the content of total sugar is greater than or equal to 57.0%. The preparation method comprises the following steps: pretreating a cubilose raw material in a boiling water bath, and sequentially carrying out alkaline protease and neutral protease enzymolysis; carrying out alcohol precipitation on supernate, redissolving, and carrying out papain enzymolysis; and after enzyme deactivation, adjusting the ethanol concentration to 75-85%, precipitating, and drying. According to the method, the cubilose polysaccharide can be efficiently enriched, the combined sialic acid structure of the cubilose polysaccharide is reserved, and the obtained component has the effects of resisting oxidation, inhibiting pathogenic microorganisms and regulating intestinal microecology.

The invention discloses a multi-enzyme compound noodle stretching agent and application thereof, and belongs to the technical field of food additives. The multi-enzyme compound noodle stretching agent is prepared from the following components in parts by mass: 1 to 10 parts of papain, 1 to 10 parts of trypsin, 1 to 10 parts of glucose oxidase, 1 to 10 parts of lipase and 10 to 30 parts of tea polyphenol. Through the synergistic effect of multienzyme compounding and tea polyphenol, the dough structure and the noodle processing performance are improved, the protein depolymerization and crosslinking degree and the protein oxidation degree of the dough can be regulated and controlled at the same time, the dough strength and ductility are considered, the cooking loss is reduced, meanwhile, the green and natural characteristics are kept, no chemical modifier is added, and the production cost is reduced. And the limitation of the existing single enzyme or chemical modifier is overcome, so that the method has a relatively good application prospect in the technical field of food additives.

The invention discloses modified hydroxytyrosol, flavored hydroxytyrosol, a preparation method of the modified hydroxytyrosol, a preparation method of the flavored hydroxytyrosol, functional food and cosmetics. Activated carbon loaded p-toluenesulfonic acid is used as a catalyst to catalyze papain to modify hydroxytyrosol, so that the effect activity of the modified hydroxytyrosol raw material is reserved, and meanwhile, the bad flavor generated by impurities in industrial production of the hydroxytyrosol raw material is remarkably reduced; furthermore, the smell and the flavor of the hydroxytyrosol raw material are remarkably improved, the application effect of the hydroxytyrosol raw material in related fields is improved, and the use sensory experience of the product is improved. The flavor of hydroxytyrosol is improved in an enzyme preparation catalysis mode, and the process method is green and safe.

The invention relates to the technical field of daily chemicals, in particular to a color-protecting laundry detergent containing plant extracts and a preparation method of the color-protecting laundry detergent. The color-protecting laundry detergent is prepared from the following components in percentage by mass: 12.5 to 18.3 percent of natural anionic surfactant, 6.4 to 9.7 percent of nonionic surfactant, 3.2 to 5.8 percent of plant polyphenol extract, 3.0 to 5.2 percent of fiber affinity natural polymer, 2.1 to 4.0 percent of bio-based chelating aid, 1.8 to 3.5 percent of natural glycoside synergist, 0.9 to 2.3 percent of pH buffering agent, 0.6 to 1.4 percent of antioxidant plant essential oil and the balance of deionized water. The compound protease comprises alkaline protease, neutral protease and papain; the invention aims to solve the technical problems that the existing laundry detergent is poor in color protection effect, insufficient in environmental protection performance and large in damage to fabrics, and provides a laundry detergent product which takes natural plant extracts as core components and has an efficient color protection function.

The invention provides a method for detecting enzyme activity of papain in a hypersensitive protein complex enzyme, which comprises the following steps: mixing the hypersensitive protein complex enzyme with an L-cysteine hydrochloride buffer solution to obtain a sample solution to be detected; adding the to-be-tested sample solution into a substrate solution containing casein, and testing a change curve of a voltage value of the to-be-tested sample solution along with time under the condition that the casein can be decomposed by papain; and determining the enzyme activity of the papain in the hypersensitive protein compound enzyme according to the change curve of the voltage value of the to-be-detected sample solution along with time. The method can solve the problem that the enzyme activity of papain in the hypersensitive protein complex enzyme cannot be accurately detected in the prior art.

The application discloses a method for preparing an oat-based beverage through biological enzymolysis and a product thereof, and comprises the following steps: continuously hydrolyzing starch, cellulose, protein and other substances in oat slurry by using high-temperature-resistant amylase, cellulase, saccharifying enzyme, papain and alkaline protease, sufficiently releasing reducing substances in the oat, simultaneously generating reducing peptides, improving the free radical scavenging capacity of the oat slurry, and improving the emulsification stability of the oat slurry due to the moderate degradation of macromolecular substances such as starch, cellulose and protein; glycerol is added in three stages at a controlled speed, so that the glycerol is fully mixed with flaxseed oil, and excessive glycerol is avoided from adhering to lipase to reduce the activity of the enzyme, thereby improving the reaction efficiency.

The invention belongs to the technical field of protein peptide preparation, and particularly relates to wheat oligopeptide with an anti-fatigue effect and a preparation method of the wheat oligopeptide. According to the method, the raw materials are subjected to enzymolysis by using the first compound enzyme containing bacillus subtilis protease and bromelain and the second compound enzyme containing trypsin, flavourzyme and papain step by step, and treatment of centrifugation, ultrafiltration and the like is combined, so that the yield and the taste of the product are improved, and the proportion of small molecular weight peptide in the product is high. Therefore, the wheat oligopeptide prepared by the method is high in yield and good in taste, not only is beneficial to improving the endurance of the body and prolonging the exercise time, but also can improve the energy metabolism condition in the body, delay the accumulation of lactic acid, urea nitrogen and creatine kinase in the body after exercise and increase the glycogen storage amount, and macroscopically shows certain anti-fatigue ability. The technical scheme of the invention has strong practicability, is beneficial to industrial production, and can be applied to preparation of anti-fatigue functional food.

This invention relates to the field of biomedical technology, specifically to a heart-spleen synergistic regulatory composition based on Chinese yam complex peptides, its preparation method, and its application in improving heart-spleen dysfunction. The method involves first gelatinizing Chinese yam, then sequentially performing primary endopeptidation with papain and secondary fine exopeptidation with flavor protease, followed by separation via a 1000 Da ultrafiltration membrane to directionally prepare a Chinese yam complex peptide with a peptide fraction of at least 90% having a molecular weight less than 1000 Da. This complex peptide is then combined with extracts of ginseng, lotus seed, longan pulp, and tangerine peel in a specific ratio. The yam peptides obtained by this invention can self-assemble with macromolecular hydrophobic components such as ginsenosides in the system to form microscopic peptide-saponin complexes, acting as biological delivery carriers and significantly improving the transmembrane absorption rate of macromolecular active ingredients in individuals with weak spleen and stomach. Simultaneously, the two-step enzymatic hydrolysis process achieves the simultaneous retention of highly active small molecules and precise debittering.

The invention relates to a pharmaceutical composition for repairing oral gingivitis and a preparation method thereof, and belongs to the technical field of biological medicine, the pharmaceutical composition comprises a lactobacillus salivarius fermentation extract, a herba violae extract, golden cicada nymph extract peptide, guava polyphenol and resveratrol; the lactobacillus salivarius fermentation extract is obtained by carrying out aerobic fermentation and anaerobic fermentation on lactobacillus salivarius to obtain a fermentation product, and purifying and extracting the fermentation product through an XAD7HP macroporous adsorption resin column; the philippine violet herb extract is obtained by performing enzymolysis on whole philippine violet herb through pectinase and cellulase and then performing enzymolysis through compound protease to obtain zymolyte, and purifying and extracting the zymolyte through a compound adsorption column. The golden cicada nymph extracted peptide is obtained by purifying and extracting 5kDa zymolyte obtained by performing step-by-step enzymolysis on golden cicada nymphs through papain and trypsin through a Q agarose gel FF adsorption column. All the components are matched for use according to a certain proportion, so that the antibacterial coating is capable of precisely resisting bacteria, has efficient anti-inflammatory and anti-oxidation properties, and is safe and reliable.

The invention relates to the field of cosmetic raw material development and cosmetics, in particular to a cosmetic composition containing oxidoreductase as well as a preparation method and application of the cosmetic composition. The composition is prepared from the following components in parts by weight: 1.5 to 3.5 parts of oxidoreductase, 0.3 to 2.5 parts of aloe barbadensis leaf extract, 0.5 to 3 parts of pimpinella diversifolia fruit extract, 0.6 to 4 parts of lysozyme, 0.8 to 2.5 parts of papain, 0.5 to 1.8 parts of lysozyme, 0.5 to 3.5 parts of pansy extract and 0.5 to 3 parts of amur corktree bark extract. The composition prepared by the invention has excellent efficiency of inhibiting propionibacterium acnes and elastinase, and has the effects of removing acnes, tightening skin and resisting aging; the composition uses active components for moisturizing, anti-inflammation, sterilization and the like, and also has good effects of sensitive repair and skin micro-ecology regulation.

The utility model relates to a device for removing impure protein in crude polysaccharide of traditional Chinese medicine by utilizing immobilized protease, which comprises a protein removal reactor loaded with the immobilized protease, a dissolved oxygen tester and a constant-temperature magnetic stirrer, and a dissolved oxygen electrode of the dissolved oxygen tester is connected to the protein removal reactor. The papain immobilized on the microcrystalline cellulose is used for carrying out enzymolysis reaction on impure protein in the traditional Chinese medicine crude polysaccharide, and the device has the characteristics of simplicity in operation, mild conditions and environment friendliness. The immobilized papain is limited between the two layers of screens, so that the problem of separation of the immobilized papain in the traditional Chinese medicine crude polysaccharide solution can be avoided, and the method has the characteristics of rapidness and convenience. The immobilized papain in the device can be expanded to immobilize other proteases, such as bromelain, subtilisin, protease K and the like, on cellulose according to protein types in different traditional Chinese medicine polysaccharide solutions.

The invention relates to the field of medicinal chemistry, in particular to a tetrahydroisoquinoline papain-like protease inhibitor shown in a formula (I) and application thereof.

The invention discloses a special water and fertilizer integrated organic fertilizer for rosa roxburghii tratt and a fertilization method. The feed additive is prepared from the following components in parts by mass: 3-5 parts of glucose, 3-5 parts of bacillus subtilis, 5-8 parts of aspergillus niger, 5-8 parts of lactobacillus plantarum, 10-16 parts of saccharomycetes, 1-3 parts of cellulase, 12-18 parts of papain, 20-30 parts of roxburgh rose pomace, 45-60 parts of brown algae, 45-60 parts of deep-sea fish leftovers and 80-100 parts of purified water. The preparation method comprises the following steps: crushing and mixing the raw materials, fermenting for 5-8 days, and filtering to obtain the brown water-soluble fertilizer. The special organic fertilizer avoids the problems of poor solubility and pipeline blockage of organic fertilizer products, realizes cyclic utilization of the roxburgh rose pomace, and enhances the environmental adaptability of soil; rosa roxburghii growth is promoted, and yield is increased.

This invention discloses a multi-enzyme preparation for industrial cell dissociation, its usage method, and applications, belonging to the field of seed cell extraction technology for industrial meat culture. The invention employs a multi-enzyme preparation composed of component 1 and component 2; component 1 includes neutral protease, hyaluronidase, and elastase; component 2 includes matrix metalloproteinase, papain, and plasmin. The invention also discloses the preparation method and applications of the multi-enzyme preparation. The rational enzyme ratio and optimized treatment conditions of this invention help protect cell membrane integrity, maintain high cell activity, and significantly improve dissociation efficiency and cell recovery. The compound enzyme preparation is highly adaptable, applicable to various tissue types and dissociation requirements, and facilitates standardized and large-scale production. Combined with automated dissociation equipment, the compound enzyme preparation enables efficient and stable industrial operation, providing important technical support and broad application prospects for the cultured meat industry, tissue engineering, and cell therapy.

The invention provides corn stigma polysaccharide, a preparation method thereof and application of the corn stigma polysaccharide in preparation of hypoglycemic drugs, and belongs to the technical field of plant polysaccharide extraction. The preparation method comprises the following steps: mixing corn stigma powder, ascorbic acid and water, adding pectinase into the mixed solution to carry out first enzymolysis, and adding cellulase and papain after 20-30 minutes to carry out second enzymolysis; after enzymolysis is completed, protein in enzymatic hydrolysate is removed, a corn stigma polysaccharide extracting solution is obtained, the corn stigma polysaccharide extracting solution is concentrated under reduced pressure, absolute ethyl alcohol is added for alcohol precipitation, then dialysis is conducted, and the corn stigma polysaccharide is obtained. The corn stigma polysaccharide prepared by the method has high yield, purity and hypoglycemic activity, and can be applied to preparation of hypoglycemic drugs.

The present application relates to the field of sodium hyaluronate preparation, in particular to a preparation method of low molecular weight sodium hyaluronate. Specifically comprising the following steps: stirring and dissolving macromolecular weight sodium hyaluronate powder into water at 45-60 DEG C to obtain a macromolecular weight sodium hyaluronate solution; cooling to 35-45 DEG C, adding a buffer solution and mixing uniformly, then adding papain and hyaluronidase with a mass ratio of (2-3):(3-6) for enzymatic reaction to obtain an enzymatic solution; adding sodium hydroxide solution to the enzymatic solution, adjusting pH to 7.5-9.0, heating to 80-90 DEG C for 20-40 minutes, then filtering to obtain a low molecular weight sodium hyaluronate solution; spray drying, and the process is simple, the conditions are mild, the product structure is not damaged, and the prepared low molecular weight sodium hyaluronate has high purity, uniform molecular weight distribution and good permeability.

The present application belongs to the technical field of nutritional functional food and health food, and particularly relates to a preparation method of marine fish skin collagen oligopeptide beneficial to promoting skin health, and a product and application thereof. The method comprises the following steps: after deep sea fish skin is pretreated by salt dissolution with a NaCl solution, trisodium citrate is added as an enzymolysis aid, and neutral protease (from Trichoderma reesei) and papain are sequentially used for two-step enzymolysis, and after enzyme inactivation, impurities are removed, sterilization is performed, and concentration, drying are performed to obtain the product. In vitro cell experiment verification shows that the product can significantly promote human skin fibroblast proliferation; in vivo animal experiment verification shows that the product can significantly increase skin moisture content, reduce transdermal water loss, increase hydroxyproline content, improve SOD activity and reduce MDA content. The product is suitable for the field of nutritional functional food and health food, and has a good application prospect in promoting skin health.

The application belongs to the technical field of food packaging film preparation, and provides a polysaccharide-based food antibacterial fresh-keeping packaging film with pH and enzyme dual response performance and a preparation method thereof, which comprises the following steps: soaking pre-cooled bacterial cellulose in a CaCl2 solution and a mineralizing solution containing sodium phytate and Na2HPO4 in sequence, oscillating mineralization, mechanically crushing the product after freeze-drying to obtain mineralized bacterial cellulose particles; covalently coupling papain and phytic acid PA to obtain an enzyme-PA conjugate; swelling beta-glucan in hot water, adding an enzyme-PA conjugate and a CAR ethanol mixture, adding 0.5M ZnCl2 dropwise after homogenization to obtain a response layer liquid; adding glycerol and mineralized bacterial cellulose particles to a chitosan acetic acid solution, homogenizing to obtain a film-forming liquid; taking the film-forming liquid to form a film by a flow casting method, pre-drying, spraying the response layer liquid, and finally drying to obtain the fresh-keeping film. The fresh-keeping film realizes physical barrier, pH and enzyme responsive release, and prolongs the shelf life of fresh meat.

The invention relates to the field of yeast extracts, in particular to a yeast extract containing arginine as well as a preparation method and application of the yeast extract. Wherein the content of arginine in the yeast extract containing arginine is greater than or equal to 6%, and the preparation method comprises the following steps: step 1, culturing a strain to obtain yeast milk; 2, extracting the yeast milk obtained in the step 1, and performing solid-liquid separation to obtain supernate; step 3, performing enzymolysis on the supernate obtained in the step 2, and performing solid-liquid separation to obtain a yeast extract containing arginine; wherein in the step 3, the enzyme used for enzymolysis comprises one or more than two selected from a substance group consisting of papain, alkaline protease and neutral protease. By adopting the preparation method disclosed by the invention, the arginine in the yeast can be more effectively enriched and can be up to 7.35% at most, and the method can be widely applied to the fields of preparing flavor modifiers of foods or human nutrition supplements and the like.

The present disclosure relates, in part, to SARS-CoV-2 papain-like protease (PLpro) inhibitor compounds of Formula (I), pharmaceutical compositions thereof, and methods of using the same for promoting an antiviral effect in a subject and / or treating, preventing, and / or ameliorating a viral infection in a subject:

This invention provides a multi-component resource utilization process for black soldier fly larvae larvae slurry, relating to the field of insect resource utilization technology. The process sequentially includes raw material pretreatment, compound enzymatic hydrolysis, lactic acid bacteria fermentation, stratified separation, and targeted treatment of each component. The compound enzymatic hydrolysis uses a combined enzyme system of trypsin and papain, and the lactic acid bacteria fermentation uses *Lactobacillus plantarum*. The fermentation parameters are: carbon-to-nitrogen ratio of 20:1, material-to-liquid ratio of 4:1 (w / v), pH of 6.5, fermentation temperature of 37°C, and fermentation time of 24 hours. This process achieves the synergistic recovery and high-value utilization of all components of black soldier fly larvae. A single process can simultaneously produce four types of products: insect oil, water-soluble fertilizer, antimicrobial peptide additives, and antibiotic-free aquatic feed ingredients, significantly improving resource utilization and industrial added value. The entire process involves no organic solvent addition, employs low-temperature enzyme inactivation to reduce energy consumption, is environmentally friendly and energy-saving, and avoids antibiotic resistance issues.

The invention relates to a preparation method of a rice bran protein ACE inhibitory peptide, and belongs to the technical field of bioactive peptide preparation. The preparation method comprises the following steps: extracting rice bran protein from defatted rice bran, carrying out step-by-step enzymolysis by using alkaline protease and papain to obtain a rice bran protein ACE crude peptide solution, centrifuging, carrying out ultrafiltration by using a 3kDa ultrafiltration tube, and purifying by using gel chromatography to obtain the rice bran protein ACE inhibitory peptide. The process is simple and efficient, the cost is controllable, the obtained ACE inhibitory peptide not only has high ACE inhibitory activity, but also has high oxidation resistance, is rich in various bioactive amino acids, can be used for efficiently preparing active peptide with strong antihypertensive potential, and provides an ideal raw material for developing novel antihypertensive food, medicine and health care products.

The invention discloses zero-additive total-effect mouthwash and a preparation method thereof, and belongs to the technical field of oral care. The mouthwash comprises a natural substrate, a bacteriostatic and deodorant component, an anti-dental calculus, whitening and repairing component, a gingival maintenance component, a natural fragrance retention system and a natural solubilizer, purified water is added to 100%, and the pH value is adjusted to 5.5-6.5. All the components are from pure plants or natural minerals, do not contain alcohol, chemical preservatives, artificial pigments, artificial essence, SLS and chlorhexidine, and can be swallowed. The green tea extract, the pomegranate peel extract and the pogostemon cablin alcohol are compounded to realize synergistic bacteriostasis, and the nano zinc-loaded hydroxyapatite is combined to resist dental calculus and the papain is used for mildly whitening, so that multiple oral care effects are realized. The preparation method is simple in process and suitable for industrial production.

This invention relates to the field of feed, specifically disclosing a method for preparing selenium- and strontium-enriched amino acid chelated feed; including the preparation of selenium / strontium-enriched amino acid fermentation products, the preparation steps of which are as follows: S1: Inoculating activated microalgae and yeast strains into a culture medium supplemented with selenium and strontium compounds, the pH of the culture medium is 6.5-7.5, the culture temperature is 25-35℃, and the culture is carried out under light and aeration conditions for 5-7 days; S2: Collecting selenium / strontium-enriched algal biomass using a flocculant, and ultrasonically treating the selenium / strontium-enriched algal biomass for 10-20 minutes, then adding soybean meal and rapeseed cake to the selenium / strontium-enriched algal biomass and stirring; S3: Adding cellulase, papain, alkaline protease, and pectinase for enzymatic hydrolysis to obtain selenium / strontium-enriched amino acid fermentation products. The selenium- and strontium-enriched amino acid chelated feed and its preparation method of this invention can improve the intestinal health of animals, increase the absorption and utilization rate of nutrients, and enhance animal immunity.

This invention relates to compounds that can be used to treat viral infections. The compounds are papain-like protease (PLpro) inhibitors.