132 results about "Hydroxyproline" patented technology

The invention belongs to the technical field of cosmetics, and discloses a wrinkle-removing and anti-aging composition containing recombinant collagen as well as a preparation method and application of the wrinkle-removing and anti-aging composition. The composition is prepared from the following components: 20.4 to 35.6 percent of glycerol, 1.1 to 3.5 percent of 1, 2-hexanediol, 8.2 to 15.4 percent of apple fruit cell culture extract, 1.6 to 3.2 percent of inositol, 0.2 to 1.0 percent of elastin, 0.1 to 1.7 percent of hydroxyproline, 0.1 to 1.0 percent of sodium polyglutamate, 0.1 to 1.0 percent of sodium hyaluronate, 0.01 to 0.1 percent of acetyl hexapeptide-8, 0.01 to 0.1 percent of fibronectin, 1.72 to 3.21 percent of soluble collagen and the balance of deionized water. The amino acid sequence of the soluble collagen is as shown in SEQ ID NO. 1. The skin care product prepared by adding the anti-wrinkle and anti-aging composition is good in safety and has the effects of resisting wrinkles, improving skin elasticity and resisting aging.

The invention discloses modified hydroxytyrosol as well as a preparation method and application thereof. The provided preparation method of the modified hydroxytyrosol comprises the following steps: in the presence of an acidic solvent, mixing hydroxytyrosol, protease and collagen for reaction, mixing a reaction product with an extraction agent, performing centrifugal layering, and collecting upper-layer components, thereby obtaining the modified hydroxytyrosol, the protease comprises one or two of neutral protease and trypsin. Under the enzymolysis action of protease, the collagen can be decomposed into amino acid monomers such as glycine, proline and hydroxyproline, and the amino acid monomers can be subjected to graft modification with hydroxytyrosol; meanwhile, collagen fragments which are not subjected to enzymolysis also exist, and are subjected to graft modification with hydroxytyrosol in the form of collagen characteristic fragments. The oxidation resistance and the stability of the obtained modified hydroxytyrosol are obviously improved compared with those of unmodified hydroxytyrosol.

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 present invention relates to the technical field of active substance extraction, and specifically relates to a mineral-containing high-purity collagen tripeptide and a preparation method therefor. A high-purity collagen tripeptide containing mineral elements and having a high hydroxyproline content and no bad flavor, particularly no bitterness is obtained by using a byproduct of aquatic product processing, i.e., fish skin or fish scales, as a raw material, using a one-step enzymolysis method, and performing nanofiltration twice.

The application discloses an acyltransferase mutant with high acetylation activity and application thereof, and belongs to the technical field of enzyme engineering. The acyltransferase mutant provided by the application contains one or more mutation sites in the 62th and 64th positions on the basis of the acyltransferase mutant with the amino acid sequence shown in SEQ ID NO. 1. The acyltransferase mutant obtained by the application has higher acyltransferase activity and catalytic efficiency than the original enzyme before mutation, and can improve the yield of N-acetyl-trans-4-hydroxyproline. Therefore, the acyltransferase mutant of the application has important significance in the efficient biosynthesis of N-acetyl-trans-4-hydroxyproline, and has wide application prospects in the fields of biological materials, medicines or cosmetics.

The invention belongs to the technical field of nutritional compositions and cosmetics, and particularly relates to an anti-aging composition and application and a product thereof. The composition provided by the invention is composed of L-ergothioneine and alpha-ketoglutaric acid, or L-ergothioneine and alpha-ketoglutaric acid salt, or L-ergothioneine and alpha-ketoglutaric acid salt. Through the synergistic effect of the L-ergothioneine and the alpha-ketoglutaric acid or the alpha-ketoglutarate, the contents of Col I and hydroxyproline in skin tissues can be remarkably increased, the expression of TGF-beta1 is up-regulated and converted, the activity of MMP-1 is inhibited, meanwhile, the malondialdehyde level is reduced to enhance the oxidation resistance, the synthesis of hyaluronic acid is promoted, and the water content of the skin is increased. The composition is simple in component and simple and convenient in preparation process, can be prepared into various products such as cosmetics, health care products or medicines, is used for achieving the effects of resisting aging, moisturizing, resisting inflammation or resisting oxidation, particularly has an excellent improvement effect on skin photoaging induced by ultraviolet rays, and is wide in application prospect.

The invention discloses a yak bone collagen peptide for improving osteoporosis and preparation and application thereof, and relates to the field of biological medicine, the yak bone collagen peptide comprises collagen peptide with the molecular weight of 500-2000 Daltons, contains a glycine-proline-hydroxyproline tripeptide core structure, can promote osteoblast differentiation and inhibit osteoclast activity, and can be used for treating osteoporosis. The amino acid sequence of the collagen peptide is any one of the following sequences: glycine-proline-hydroxyproline-glycine-glutamic acid-arginine, and the amino acid sequence of the collagen peptide is any one of the following sequences: glycine-proline-hydroxyproline-glycine-glutamic acid-arginine; and the amino acid is glycine, proline, hydroxyproline, serine, leucine and alanine. The yak bone collagen peptide has a unique glycine-proline-hydroxyproline tripeptide structure, the molecular weight is controlled within the range of 500-2000 Daltons, the structure can promote osteoblast differentiation and inhibit osteoclast activity at the same time, and the problem that a traditional osteoporosis treatment medicine is single in function is solved.

The invention relates to the technical field of collagen extraction, and provides a collagen extraction process for increasing hydroxyproline content, which sequentially comprises the steps of raw material pretreatment, deliming and degreasing, directional enzymolysis, gradient pressure-temperature synergistic extraction, purification, concentration and drying, a composite pretreatment agent containing a proline hydroxylase activator, EDTA-2Na and neutral protease is adopted in the raw material pretreatment; deashing and degreasing are combined with a chelating agent solution and ultrasonic treatment; a compound enzyme solution composed of trypsin, papain and proline hydroxylase is used for directional enzymolysis; a two-stage gradient pressure-temperature cooperation mode is adopted for extraction; purification is realized through combination of gel filtration chromatography and ion exchange chromatography; and finally carrying out freeze concentration and vacuum freeze drying to obtain the product. According to the process, through a multi-step synergistic effect, the content of hydroxyproline in collagen is remarkably increased, the product purity is high, natural functional characteristics are reserved, and the process is suitable for the fields of food, cosmetics, biological medicine and the like.

Provided are a preparation method for a yeast-expressed type I recombinant human collagen with a tri-helical structure and use thereof. The preparation method comprises the steps of performing fermentation using an engineered bacterium and performing purification to obtain the type I recombinant human collagen with a tri-helical structure. A method for constructing the engineered bacterium comprises the step of transforming a host bacterium with plasmids pMChZ-α1(I), pMCrN-α2(I), pPIC9K-P4H(DP)-1, and pMCeH-[α1(I)] 2α2(I) to construct the engineered bacterium. The type I recombinant human collagen with a tri-helical structure prepared using the preparation method comprises hydroxyproline, and hydroxyproline accounts for 30% or more of total proline.

A method for preparing nondenatured collagen type II for alleviating joint pain includes pulverizing a cartilage raw material and defatting to obtain a total protein crude extract; adding anhydrous ethanol to the total protein crude extract, soaking, stirring, and centrifuging to obtain an anhydrous ethanol insoluble material; dissolving the anhydrous ethanol insoluble material in water, adjusting pH to acidic, stirring and centrifuging to obtain an acid-insoluble material; dissolving the acid-insoluble material in water, performing enzymatic hydrolysis and centrifuging to obtain an enzymatic hydrolysis precipitate; dissolving the enzymatic hydrolysis precipitate in water, followed by performing co-fermentation, and centrifuging to obtain a fermentation precipitate; and adding a water activity regulator to the fermentation precipitate, and then drying to obtain the nondenatured collagen type II. The content of protein, hydroxyproline and nondenatured collagen type II in the prepared nondenatured collagen type II is high, and the shelf life is prolonged.

The invention belongs to the field of bioactive protein peptide materials, and provides an animal-derived composite fermented skin-tendering protein peptide and a preparation method thereof. According to the invention, bovine-derived collagen and fish-derived protein are subjected to synergistic fermentation to prepare a protein peptide core, and the outer surface of the protein peptide core is coated with an edible gelatin and chondroitin sulfate composite layer; the excellent performance that a small molecule peptide core with the molecular weight being 500-1500 Da, a stable coating layer with the coating rate being 80-99%, the glycine-proline-hydroxyproline sequence collagen peptide fragment accounting for 30-60% and the pH responsive swelling ratio being 1.5-3.0 are achieved, the technical problems that traditional protein peptide is poor in stability and low in bioavailability are solved, and the protein peptide has wide application value in the field of skin care products.

The invention relates to a special microbial agent fertilizer for konjak, and aims to break through the industrial bottlenecks of high incidence of soft rot, damage caused by waterlogging stress and glucomannan synthesis obstacles in konjak cultivation. According to the core technical scheme, the activity of soft rot fungus pectinase is inhibited in a targeted mode through clostridium butyricum, and efficient polymerization of gulcomannan molecular chains is driven in cooperation with a hydroxyproline precursor provided by fish meal; a sulfonic acid group of biochemical potassium fulvate is used for blocking waterlogging free radical poison, and a brown sugar-trehalose carbon source ratio is optimized to stabilize cell osmotic pressure in an expansion period; and a supplementary application mechanism based on a precipitation threshold (greater than or equal to 10mm) and a copper preparation application isolation regulation are established in a matched manner. According to the technology, the three-effect synergy that the soft rot prevention and control rate is larger than 90%, the glucomannan viscosity improvement rate is larger than 70% and the waterlogging survival rate is larger than 85% is achieved, and the core restriction of high-yield and high-quality production of the konjak is systematically solved.

The present invention relates to an ambroxol-ibuprofen cocrystal dry powder inhaler, a preparation method and application thereof, and belongs to the professional field of pharmaceutical preparations. The dry powder inhaler is mainly composed of ambroxol, ibuprofen and lactose, the molar ratio of ambroxol to ibuprofen is 1:1, and the mass ratio of lactose to ambroxol-ibuprofen cocrystal is 5-35%. The results of the rat lung tissue distribution experiment showed that the administration method of dry powder inhalation can significantly enhance the drug delivery efficiency in the lungs and greatly prolong the drug retention time in the lungs compared with the traditional intravenous administration. Pharmacodynamic experiments further revealed that the ambroxol-ibuprofen cocrystal dry powder inhaler can effectively inhibit the active expression of inflammatory factors in model animals, and reduce the accumulation of hydroxyproline (HYP) in lung tissue and serum, improve anti-fibrosis and anti-inflammatory capabilities, improve oxidative stress capabilities, thereby helping to delay the pathological process of pulmonary fibrosis, showing great development potential as an anti-pulmonary fibrosis drug.

This invention belongs to the fields of genetic engineering and enzyme engineering, specifically relating to proline hydroxylase mutants and their application and methods in hydroxyproline production. This invention provides p4h... G141A p4h S85A p4h V126A p4h H125A p4h S205A p4h D122A p4h S211A Mutations at specific sites significantly increased the production of hydroxyproline and decreased the proportion of proline in the mutant enzyme. Further saturation mutations at these sites, combined with the dominant mutations, yielded strains with even better performance, such as p4h. S85Q‑V126A p4h S85A‑V126T p4h G141A‑H125S p4h G141A‑H125T Compared with traditional chemical methods, this process has lower production costs, is more environmentally friendly, and allows for large-scale continuous production.

The invention provides oral recombinant human elastin capable of repairing skin subacute aging injury and application of the oral recombinant human elastin, and belongs to the technical field of biotechnology and functional food. The oral recombinant human elastin capable of repairing skin subacute aging injury is prepared in a gene recombination expression mode. The recombinant human elastin has both a beta-spiral hydrophobic structure domain and a lysine-rich hydrophilic region, and shows excellent biological safety and biological activity; after the traditional Chinese medicine composition is prepared into an oral preparation, skin wrinkles can be remarkably reduced, the skin water content and dermis density can be improved, transdermal water loss can be reduced, the hydroxyproline level can be increased, collagen generation can be promoted, elasticity can be recovered, and skin oxidative stress reaction can be effectively inhibited. The method solves the problems that the natural elastin source is limited and the biological safety is insufficient, and has a wide industrialization prospect.

The invention belongs to the technical field of biochemical engineering, and relates to an industrial extraction method and application of L-hydroxyproline adapted to the scale of a 30T fermentation tank, and the extraction method comprises the following steps: preparing raw materials; recycling membrane filtration and mother liquor; decoloring is performed; decarburization; evaporating, concentrating and crystallizing; performing centrifugal separation; drying and crushing. The method solves the technical problems that the yield is low (generally less than 70%), the process flow is long (multiple times of chromatography / recrystallization is needed), the product purity is difficult to reach the standard (most 98-99.5%) and the like, the L-hydroxyproline fermentation liquor produced by a 30T fermentation tank is used as a treatment object, efficient extraction is realized through a pretreatment-purification-refining three-stage process system, and the method is suitable for industrial production. According to the method, the primary mother liquor generated by centrifugal separation is innovatively applied to the next batch of membrane filtration process, so that raw material recycling is realized, the purity of the final product stably reaches 99.9%, the overall yield is increased to 75%, and the method has the advantages of simplified process, stable yield and controllable quality, and can be directly applied to large-scale industrial production of L-hydroxyproline.

This invention provides a highly water-soluble composition for promoting autophagy and its application. The composition comprises 5-hydroxyflavone, acetylhydroxyproline, and a suitable solvent. This composition is a unique vesicular composition that enables efficient delivery and synergistic effects of the two active ingredients. It promotes autophagy, has improved solubility, stability, and antioxidant properties, and can prevent and repair skin photodamage at its source. This invention also discloses a method for preparing this composition and its applications.

The present application relates to a kind of whole cell catalytic synthesis N-acetyl-trans-4-hydroxyproline method, belong to biological catalysis technical field.The present application is constructed by mutating acyltransferase and heterologous expression gene engineering bacteria, successfully realized using whole cell catalytic synthesis N-acetyl-trans-4-hydroxyproline, avoids the problem of enzyme instability, reduces the separation cost of enzyme and product.On this basis, the present application improves the yield of N-acetyl-trans-4-hydroxyproline by optimizing catalytic time, cell addition amount, the type and addition amount of additive, and the yield reaches 239mg / L.The present application is a kind of N-acetyl-trans-4-hydroxyproline preparation method with lower cost, lower equipment demand, more suitable for industrial production.

A collagen-boosting supplement that contains at least 4, optionally at least 10, collagen building block amino acids and is substantially free of histidine. The building block amino acids may be selected from: Glycine, L-Proline, L-Hydroxyproline, L-Glutamic Acid, L-Alanine, L-Arginine, L-Aspartic Acid, L-Serine, L-Leucine, L-Lysine, L-Hydroxylysine, L-Valine, L-Phenylalanine, L-Threonine, L-Isoleucine, L-Methionine, and L-Tyrosine. The supplement may further comprise: vitamin C; one or more mast cell stabilisers which may be selected from: quercetin, molybdenum, bromelain, DAO (diamine oxidase), Urtica Dioica (stinging nettle), Nigella Sativa (black cumin), Zingiber (ginger), Scutellaria baicalensis (Chinese skullcap), Sambucus (Elderberry), Aloe Vera, Syzygium aromaticum (clove), and matcha; one or more collagen-strengthening herbs which may be selected from: Bilberry, Centella, and Astragulus; one or more Glucosaminoglycans (GAGs) which may be selected from: Hyaluronic acid, glucosamine, and chondroitin; one or more antioxidants which may be selected from: astaxanthin and resveratrol; and / or one or more cofactors which may be selected from: zinc, biotin, silicon, manganese, magnesium, Vitamin D, Vitamin A, Vitamin E, and iron. The supplement may be a foodstuff, medicament, nutraceutical, or cosmetic. The supplement may be used to treat hypermobile Ehlers-Danlos syndrome (hEDS) while reducing the likelihood of mast cell degranulation through histamine activation.

The invention discloses an application of a compound fresh bamboo juice in a guinea pig asthma model, and relates to the field of medicines, a Hartley albino guinea pig is adopted to construct an OVA induced asthma model, and the model is verified to be successfully constructed through evaluation indexes; evaluating the efficacy of the successfully constructed guinea pig asthma model by using different doses of compound fresh bamboo juice, and evaluating the efficacy of the guinea pig asthma model by scoring guinea pig capsaicin stimulation cough inducing times, alveolar lavage fluid leukocyte number, inflammatory factor content, lung tissue hydroxyproline content and behavioral signs. And evaluating the treatment effect of the compound fresh bamboo juice through Western blot detection, lung histopathology and immunofluorescence staining indexes. In a guinea pig asthma model, high-dose and medium-dose groups of the compound fresh bamboo juice can be used for remarkably reducing the number of cough, reducing the number of white blood cells in alveolar lavage fluid and the level of inflammatory factors and inhibiting pulmonary fibrosis, and a good treatment effect is shown. The results provide powerful support for potential application of the compound fresh bamboo juice in asthma treatment.

The invention discloses an application of a P4HA1 inhibitor in preparation of a medicine for treating congenital megacolon-related enterocolitis, deeply clarifies an immune metabolic axis of 'P4HA1-hydroxyproline-eIF5A-IRF4-IL17', and discloses a new mechanism that metabolite hydroxyproline regulates the activity of eIF5A and promotes nuclear translocation of IRF4 so as to enhance TH17 cell mediated inflammatory response. Therefore, a brand new perspective is provided for understanding metabolic immune regulation of intestinal inflammation. By using the P4HA1 inhibitor (such as 1, 4-DPCA), secretion of IL-17 can be effectively inhibited, intestinal inflammation injury of HAEC model mice can be remarkably relieved, and a clear pharmacodynamic basis is achieved.

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 discloses an engineering bacterium for producing N-acetyl-trans-4-hydroxyproline and application thereof and belongs to the technical field of biotechnology.The application realizes fermentation synthesis of N-acetyl-trans-4-hydroxyproline by taking proline as a substrate through mutation of acyltransferase and introduction of exogenous proline-4-hydroxylase.The application has the advantages of low production cost, short fermentation period and high strain stability and has high economic benefits.The recombinant strain constructed by the application can convert 0.5M of proline into 19.64mg / L of N-acetyl-trans-4-hydroxyproline.

The invention belongs to the technical field of recombinant collagen sequence analysis, and discloses a recombinant collagen sequence analysis method based on AI deep learning. Comprising the following steps: extracting a natural III-type collagen sequence; applying the natural III-type collagen sequence to the trained model to generate a thermodynamic diagram; generating an optimized natural III type collagen sequence based on the thermodynamic diagram; performing fine tuning on the AlphaFold2 model by using the fine tuning data set, and obtaining an integrated structure model by introducing spiral torsion constraint and hydroxyproline simulation parameters; loading the optimized natural III-type collagen sequence, and predicting the stability of the triple helix structure of the sequence through the structure model; and extracting a natural III-type collagen sequence which passes the stability detection, and outputting a report file by using a skin permeability prediction model to realize recombinant collagen sequence analysis based on AI deep learning.

The present invention provides nutritional compositions for use in weight loss dietary interventions or in particular weight maintenance after dietary interventions, preferably after low calorie dietary interventions. The nutritional composition comprises one or more amino acids selected from the group consisting of proline, histidine, glycine and / or hydroxyproline, or a combination thereof, which can be used to assist in weight loss in obese subjects that are resistant to weight loss only by means of caloric limiting dietary intervention. In addition, the nutritional composition of the present invention may be used to help maintain the weight loss, particularly after dietary intervention.

The present application relates to the technical field of content detection, in particular to a method for rapidly detecting the content of hydroxyproline in mouse lung tissue, which comprises the following steps: obtaining the original sampling spectrum of the lung tissue of the mouse to be detected at different preset sampling points, and obtaining a non-lung tissue interference characteristic base matrix containing whole blood characteristics and cartilage characteristics; setting an orthogonal filter operator and determining a lung interstitium characteristic spectrum vector; constructing a reference spectrum vector and determining a relative spectral response factor; constructing a spectral minimum spanning tree and determining a signal contribution weight based on the spectral minimum spanning tree and the relative spectral response factor; generating a whole lung fibrosis synthetic spectrum according to the signal contribution weight and the lung interstitium characteristic spectrum vector, and detecting the content of hydroxyproline based on the whole lung fibrosis synthetic spectrum. The present application considers the non-lung tissue interference containing whole blood characteristics and cartilage characteristics when detecting the content of hydroxyproline, which improves the rationality of the detection of the content of hydroxyproline to a certain extent.

This invention provides the application of *Ackermania guangxiensis* extracellular polysaccharide in the preparation of anti-aging products, belonging to the technical field of microbial polysaccharide pharmaceutical applications. This invention extracts extracellular polysaccharides from *Ackermania guangxiensis* using the TCA precipitation method. Animal experiments show that *Ackermania guangxiensis* extracellular polysaccharide can effectively reduce MDA content in aging model mice while increasing SOD activity; it improves the thinning of the dermal layer, reduction and loosening of collagen fibers, and other signs of aging in model mice, and increases the hydroxyproline content in the skin; furthermore, it can activate the expression of BDNF and TrKB genes in the mouse hippocampus and alleviate problems such as slow movement, cognitive impairment, and memory decline in model mice. Therefore, the *Ackermania guangxiensis* extracellular polysaccharide provided by this invention has good anti-aging and antioxidant activity and can be used to prepare various anti-aging products.

Provided is a peptide compound comprising the amino acid sequence: Xaa1-Lys-Xaa3-Ser-Xaa5-Xaa6-Xaa7-Xaa8-Xaa9-Xaa10-Xaa11-Xaa12-Xaa13 wherein: Xaa1 represents Ala or Ser, or is absent, wherein the N-terminal amino acid optionally includes an N-terminal 3,4-dihydrocinnamic acid group; Xaa5 represents Tyr, DOPA or a single bond; Xaa3 and Xaa6 independently represent Pro, Hyp or diHyp; Xaa7, Xaa8, Xaa9, Xaa10, and Xaa11 are each optional (in which case Xaa6 is bonded to Xaa12), and are independently selected from the group Pro, Hyp, diHyp, Thr, DOPA and Tyr; Xaa12 represents Pro, Hyp, diHyp, Thr, DOPA or Tyr; and Xaa13 represents Lys or is absent, as well as regioisomers, stereoisomers, and pharmaceutically- or cosmetically-acceptable salts of said peptide compound, provided that when the N-terminal 3,4-dihydrocinnamic acid group is not present, Xaa1 represents Ala or is absent and Xaa13 represents Lys, then Xaa12 represents Pro, Hyp, diHyp or Thr. The compounds are particularly useful in for treatment of conditions characterised by inflammation, including wounds, burns, and disorders of the mucosa, such as anorectal diseases, inflammatory bowel diseases, gynaecological diseases and dental diseases.

The invention discloses a colla corii asini in-vivo bioactive component cyclic dipeptide and a discovery method thereof, and belongs to the technical field of bioactive component analysis and application. The method comprises the following steps: establishing a rat donkey-hide gelatin administration model and collecting a sample, performing solid-phase extraction on the sample, performing LC-MS / MS peptidomics analysis and PEAKS database search, screening exogenous oligopeptides based on a feature-based molecular network (FBMN), performing cyclic dipeptide targeted metabonomics identification, and verifying cell viability. According to the method, 29 cyclic dipeptides are produced by metabolism in donkey-hide gelatin, and the cyclic dipeptides containing hydroxyproline (Hyp) can significantly improve the survival rate of HT-22 cells damaged by glutamic acid or hydrogen peroxide induction and have neuroprotective activity.

The invention provides an antioxidant collagen peptide capable of relieving xerophthalmia and a preparation method and application thereof, the amino acid sequence of the collagen peptide is GSVGEpGPL, and Ep is hydroxyproline. The collagen polypeptide disclosed by the invention has a remarkable antioxidant effect, can effectively relieve damage to eye tissues caused by oxidative stress, and shows excellent safety (low toxicity) at the same time. Besides relieving xerophthalmia caused by oxidative stress, the collagen peptide can also be widely applied to preparation of eye care compositions.