Tilapia skin peptide, preparation method therefor, and use thereof in preparation of Anti-aging related product

Abstract

A tilapia skin peptide having anti-aging activity. The tilapia skin peptide is isolated and identified from a tilapia skin enzymatic hydrolysate, and the tilapia skin peptide is IL, FGP, or LPGL.

Description

Tilapia skin peptides, their preparation methods, and their uses in the preparation of anti-aging related products

[0001] Related applications

[0002] This application claims priority to Chinese patent application filed on October 14, 2024, application number 202411430831.2, entitled "Tilapia skin peptide and its preparation method and its use in the preparation of anti-aging related products", the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application belongs to the field of biotechnology and relates to tilapia skin peptides, their preparation methods, and their use in the preparation of anti-aging related products. Background Technology

[0004] Skin aging is a complex and diverse process, mainly divided into endogenous aging and exogenous aging. Endogenous aging includes inevitable physiological changes that occur over time and is influenced by gene expression, nutrition, endocrine function, and immunity. Exogenous aging is caused by external factors such as air pollution, smoking, malnutrition, climate, and ultraviolet radiation.

[0005] In recent years, with the emergence of an aging population, people are paying more attention to their skin health in addition to their physical health. As the concept of gentle, green, and effective skincare gains popularity, skincare methods are shifting from topical application to oral intake. This avoids causing severe skin irritation, inflammation, or even allergies, achieving improvement in skin condition from the inside out and delaying skin aging.

[0006] Polypeptides are low-molecular-weight bioactive peptides with specific functions, obtained through deep hydrolysis. Compared to proteins, polypeptides have a higher absorption rate and stronger biological activity in the human body, while also exhibiting higher safety and better biocompatibility. Based on these superior properties, people are increasingly favoring the use of polypeptides to delay skin aging. Compared to pharmaceuticals, functional foods with anti-aging activities avoid the drawbacks of long drug development and clinical trial cycles, and thus have broader development prospects.

[0007] This application aims to provide highly effective and reliable active peptides that have significant effects in delaying skin aging. Summary of the Invention

[0008] In order to overcome the defects and shortcomings of traditional technologies, according to various embodiments of this application, peptides in the enzymatic hydrolysis products of tilapia skin are screened to obtain peptides that simultaneously possess cell protection and repair functions, antioxidant activity, skin barrier protection function, inhibition of matrix metalloproteinase activity, and increase collagen content.

[0009] In some implementations, this application is achieved through the following technical solutions:

[0010] In the first aspect, this application provides a tilapia skin peptide with anti-aging activity, said tilapia skin peptide being isolated and identified from tilapia skin enzyme products, said tilapia skin peptide being IL, FGP or LPGL.

[0011] In some embodiments, the preparation method of the tilapia skin enzymatic hydrolysate in the above-mentioned tilapia skin peptide is as follows:

[0012] Take an appropriate amount of frozen tilapia skin, thaw it with water, then soak it in 5-10% NaOH to remove impurities. Rinse it several times with clean water until the pH of the washing water is neutral. Add 0.05-2% alkaline protease and enzymatically hydrolyze for 2-8 hours. Then, inactivate the enzyme in a boiling water bath. Take the enzymatic hydrolysate and pass it through a 200-mesh silk cloth to remove impurities. Filter to remove suspended impurities, then centrifuge at 4°C, take the supernatant, and freeze-dry it to obtain the tilapia skin enzymatic hydrolysate.

[0013] In a second aspect, this application provides a method for preparing the tilapia skin peptide described in the first aspect above, wherein the tilapia skin peptide is obtained by enzymatic hydrolysis and separation from tilapia skin.

[0014] In a third aspect, this application provides a method for preparing the tilapia skin peptide described in the first aspect above, wherein the tilapia skin peptide is prepared by solid-phase synthesis.

[0015] In a fourth aspect, this application provides the use of the tilapia skin peptide described in the first aspect above in the preparation of anti-aging related products.

[0016] In some embodiments, the product used in the above-described applications is an oral or topical product.

[0017] In some embodiments, in the above-described uses, the product is a pharmaceutical, functional food, health product, beverage, nutritional supplement, or cosmetic.

[0018] In some embodiments, for the purposes described above, the product is an oral solution, tablet, pill, liquid suspension, injection, granule, powder, capsule, beverage, energy bar, chewing gum, or candy.

[0019] In some embodiments, in the above-described uses, the product is a toner, lotion, serum, cream, or mask.

[0020] In some embodiments, in the above-described uses, the product has a protective effect against UV-induced cell damage, possesses antioxidant activity, repairs damaged cells, protects the skin barrier, and delays skin aging.

[0021] Details of one or more embodiments of the present invention are set forth in the following drawings and description. Other features, objects, and advantages of the invention will become apparent from the specification, drawings, and claims. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments and examples of this application, and to more completely understand this application and its beneficial effects, the accompanying drawings used in the description of the embodiments or examples will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of this application. Those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0023] Figure 1 is the total ion chromatogram of the enzymatic hydrolysis product of tilapia skin in Example 2;

[0024] Figure 2 shows the molecular structural formulas of GPH, IL, FGP, and LPGL in Example 3;

[0025] Figure 3 shows the effect of peptides on the survival rate of UV-damaged cells in Example 4, where A represents MSF and B represents HACAT.

[0026] Figure 4 shows the effect of peptides on MDA content in UV-damaged cells in Example 5, where A represents MSF and B represents HACAT.

[0027] Figure 5 shows the effect of the four peptides on the ROS content in cells in Example 5;

[0028] Figure 6 shows the effect of the three polypeptides on the expression of barrier proteins in cells in Example 6;

[0029] Figure 7 shows the effect of the three polypeptides on the expression of type I collagen in cells in Example 7;

[0030] Figure 8 shows the inhibition rate of collagenase activity by the three polypeptides in Example 7;

[0031] Figure 9 shows the inhibition rate of MMP protein expression by the three peptides in Example 8;

[0032] Figure 10 shows the effect of the four peptides in Example 9 on the migration rate of HaCaT cells. Detailed Implementation

[0033] The present application will be further described below with reference to specific embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the present application.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of this application.

[0035] In a first aspect, in some embodiments, a tilapia skin peptide with anti-aging activity is provided, said tilapia skin peptide being isolated and identified from tilapia skin enzyme products, said tilapia skin peptide being IL, FGP or LPGL.

[0036] In some embodiments, the preparation method of the tilapia skin enzymatic hydrolysate in the above-mentioned tilapia skin peptide is as follows:

[0037] Take an appropriate amount of frozen tilapia skin, thaw it with water, then soak it in 5-10% NaOH to remove impurities. Rinse it several times with clean water until the pH of the washing water is neutral. Add 0.05-2% alkaline protease and enzymatically hydrolyze for 2-8 hours. Then, inactivate the enzyme in a boiling water bath. Take the enzymatic hydrolysate and pass it through a 200-mesh silk cloth to remove impurities. Filter to remove suspended impurities, then centrifuge at 4°C, take the supernatant, and freeze-dry it to obtain the tilapia skin enzymatic hydrolysate.

[0038] In a second aspect, in some embodiments, a method for preparing the tilapia skin peptide described in the first aspect is provided, wherein the tilapia skin peptide is obtained by enzymatic hydrolysis and separation from tilapia skin.

[0039] In a third aspect, in some embodiments, a method for preparing the tilapia skin peptide described in the first aspect is provided, wherein the tilapia skin peptide is prepared by solid-phase synthesis.

[0040] In a fourth aspect, some embodiments provide the use of the tilapia skin peptides described in the first aspect above in the preparation of anti-aging related products.

[0041] In some embodiments, the product used in the above-described applications is an oral or topical product.

[0042] In some embodiments, in the above-described uses, the product is a pharmaceutical, functional food, health product, beverage, nutritional supplement, or cosmetic.

[0043] In some embodiments, for the purposes described above, the product is an oral solution, tablet, pill, liquid suspension, injection, granule, powder, capsule, beverage, energy bar, chewing gum, or candy.

[0044] In some embodiments, in the above-described uses, the product is a toner, lotion, serum, cream, or mask.

[0045] In some embodiments, in the above-described uses, the product has a protective effect against UV-induced cell damage, possesses antioxidant activity, repairs damaged cells, protects the skin barrier, and delays skin aging.

[0046] Compared with the prior art, this application has the following advantages:

[0047] (1) Through screening of tilapia skin enzymatic hydrolysate, the applicant has for the first time obtained three peptides that simultaneously protect cell activity, inhibit oxidative damage, protect the skin barrier, enhance collagen synthesis, inhibit collagen degradation, and repair skin damage without significant side effects.

[0048] (2) The innovation of this application is mainly reflected in the functions of the three substances IL, FGP and LGPL in anti-oxidation, repair, promoting collagen synthesis and inhibiting collagen degradation. It comprehensively emphasizes the protective effect of the three peptides against oxidative damage to cells, the prevention of collagen loss and the improvement of the ability to repair damage, and thus emphasizes the role of the above three peptides in inhibiting skin aging.

[0049] (3) The composition of this application can be used to prepare various products related to anti-skin aging and has broad application prospects.

[0050] Where specific techniques or conditions are not specified in the examples, they shall be performed in accordance with the techniques or conditions described in the literature in this field, or in accordance with the product instructions. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased through legitimate channels.

[0051] Unless otherwise specified, the experimental methods used in the following embodiments are conventional methods. Unless otherwise specified, the experimental materials used in the following embodiments are commercially available products.

[0052] Example 1: Preparation process of tilapia skin peptides

[0053] Take an appropriate amount of frozen tilapia skin, thaw it with water at a ratio of 1:3 (w / v), then soak it in 7% NaOH to remove impurities, rinse it several times with clean water until the pH of the washing water is neutral, add 0.1% alkaline protease, and enzymatically hydrolyze for 5 hours. Then, inactivate the enzyme in a boiling water bath for 15 minutes. Take the enzymatic hydrolysate and pass it through a 200-mesh silk cloth to remove impurities. Filter to remove suspended impurities, then centrifuge at 8000 r / min and 4℃ for 15 minutes. Take the supernatant and freeze-dry it to obtain the tilapia skin enzymatic hydrolysate.

[0054] Example 2: Identification of polypeptide sequences

[0055] Sample pretreatment: The sample is desalted and then subjected to mass spectrometry detection.

[0056] Chromatographic separation: Mobile phase A was deionized water containing 0.1% formic acid, and mobile phase B was an aqueous solution of acetonitrile containing 0.1% formic acid (acetonitrile content 84%). The column (0.15 mm x 150 mm, RP-C18, Column Technology Inc.) was first equilibrated with 95% solution A. The sample was loaded into Zorbax 300SB-C18 peptide traps (Agilent Technologies, Wilmington, DE) via an autosampler, and then separated by liquid chromatography. The relevant elution conditions are shown in Table 1.

[0057] Table 1: LC-MS / MS elution conditions

[0058] Mass spectrometry identification: The enzymatic hydrolysis products were separated by capillary high-performance liquid chromatography and then analyzed by mass spectrometry using a Q Exactive mass spectrometer (Thermo Fisher). Analysis time: 60 min. Detection mode: positive ion. The mass-charge ratio of the peptide and peptide fragments was determined by the following method: 10 fragment spectra were acquired after each full scan (MS2scan).

[0059] Database search: The raw mass spectrometry test file was searched for in the corresponding database using MaxQuant 1.5.5.1 software, and finally the protein identification and quantitative analysis results were obtained.

[0060] The peptide sequences of the enzymatic hydrolysate of tilapia skin were identified by mass spectrometry, and the peptide sequences with relatively high content were selected for chemical synthesis. Figure 1 shows the total ion chromatogram of the enzymatic hydrolysate of tilapia skin. Among them, IL, FGP, and LPGL showed high reliability and large peak areas. At the same time, the online screening tools https: / / www.innovagen.com / proteomics-tools and https: / / webs.iiitd.edu.in / raghava / toxinpred / showed that these three peptides have high solubility, are non-toxic, and have good stability. Therefore, the three peptides IL, FGP, and LPGL will be further studied.

[0061] Example 3: Synthesis of peptides GPH, IL, FGP, and LPGL by solid-phase synthesis

[0062] The resin was swollen, washed, and dried to remove the Fmoc protecting group. The amino acids constituting the peptide were weighed and reacted in a shaker at 30°C for 1 hour to perform a condensation reaction. This process of removal-protection-condensation was repeated until all amino acids were linked. The target peptide was separated from impurities by high-performance liquid chromatography (HPLC) to obtain a pure peptide (>95%), which was then lyophilized into a powder. Figure 2 shows the molecular structures of four peptides: GPH (control peptide), IL, FGP, and LPGL.

[0063] Example 4: Effects of peptides on the survival rate of UV-damaged MSF and HACAT cells

[0064] Adenosine triphosphate (ATP) is a constant substance within cells, and the amount of endogenous ATP can reflect cell activity. Cell viability was quantitatively detected using ATP. HACAT cells were purchased from Zhejiang Meisen Cell Technology Co., Ltd., while MSF cells were obtained by removing the head, tail, and limbs of C57BL / 6J P0 suckling mice, leaving the trunk, and surgically cutting the mice from the neck along the rump to collect skin tissue. The skin tissue was then digested with skin tissue digestion solution to isolate mouse skin fibroblasts.

[0065] MSF cells and HACAT cells were respectively loaded with 7×10 3 / hole, 1×10 4 Cells were seeded at the specified density in 96-well plates and DMEM medium was added. Six replicates were set up for each group. The control group was not seeded and the same volume of medium was added. After 24 hours of culture, the model control and sample groups were incubated using UV microscopy for 70 minutes. The old medium was then discarded. Fresh medium was added to the control and model wells, and the sample wells were incubated with medium containing the sample. After another 18 hours of culture, the old medium was discarded, and 100 μL of ATP was added to each well. The plates were lysed at 37°C for 1 hour. The supernatant was transferred to a microplate, and the RLU value was measured using a chemiluminescence analyzer.

[0066] The results are shown in Figure 3. Compared with the control group, the survival rates of HACAT and MSF cells in the UV-induced group were significantly reduced, but increased significantly after drug administration. Specifically, the cell survival rates in the LGPL, FPG, and IL groups were all higher than those in the GPH group. This indicates that the selected peptides help protect cells, and their cell-protective ability is higher than that of the GPH group.

[0067] Example 5: Effects of peptides on the antioxidant activity of UV-damaged cells

[0068] 1. MDA content determination

[0069] Add 100 μL of RIPA lysis buffer to the cell sample, incubate at 4℃ for 30 min, centrifuge at 10000 rpm for 10 min, collect the supernatant, quantify, and adjust the density to 2 mg / mL. MDA standard curve: Prepare a 2 mM MDA standard. Dissolve 10 μL of the 2 mM MDA standard in 200 μL (ddH2O); add 600 μL of TBA + standard or 200 μL of sample, incubate at 95℃ for 60 min, then incubate on ice for 10 min; transfer 200 μL to 96 wells, measure the OD value at 532 nm using a full-wavelength microplate reader, and calculate the MDA content.

[0070] The results, shown in Figure 4, indicate that UV irradiation significantly increased MDA levels in both MSF and HACAT cells. After intervention with LGPL, FPG, IL, and GPH, MDA levels in MSF cells decreased, and the MDA levels in the LGPL, FPG, and IL groups were all lower than those in the GPH group. Furthermore, LGPL, FPG, IL, and GPH also inhibited MDA levels in HACAT cells. The anti-lipid peroxidation effects of the four peptides, from strongest to weakest, were LGPL, IL, FPG, and GPH. In conclusion, LGPL, FPG, and IL exhibit significant anti-lipid peroxidation effects in both HACAT and MSF cells, and their effects are all superior to those of GPH.

[0071] 2. ROS content determination

[0072] MSF cells and HACAT cells were respectively loaded with 10 × 10 4 / hole and 15×10 4 Cells were seeded at a density of 1 / 2 well in 6-well plates and DMEM medium was added. Six replicates were set up for each group. The control group was not seeded and the same volume of medium was added. After 24 h of culture, the model control and sample groups were subjected to UV-induced cell modeling for 70 min. The old medium was then discarded. Fresh medium was added to the control and model wells, while the sample group was replaced with medium containing the sample. After another 18 h of culture, the old medium was discarded. DCFH-DA was diluted 1:1000 with serum-free culture medium to a final concentration of 10 μmol / L. The cell culture medium was removed, and the cells were washed once with PBS. 1 mL of diluted DCFH-DA was added to each well, and the cells were incubated at 37°C for 20 min. The cells were washed three times with serum-free medium to remove any uninoculated DCFH-DA and reduce fluorescence background. Finally, the 6-well plates were photographed under a fluorescence microscope.

[0073] As shown in Figure 5, the ROS levels in both MSF and HACAT cells increased after UV irradiation compared to the control group. After intervention with LGPL, IL, FGP, and GPH, the ROS levels in MSF cells decreased. However, LGPL, IL, and FGP showed more significant inhibitory effects on cellular oxidative stress compared to GPH. Furthermore, after intervention with LGPL, IL, FGP, and GPH, the ROS levels in HACAT cells, from lowest to highest, were LGPL, IL, FGP, and GPH. These results indicate that LGPL, IL, and FGP can effectively inhibit UV-induced cellular oxidative stress, reduce intracellular ROS release, and alleviate UVB-induced cellular aging and degeneration.

[0074] Example 6: The protective effect of three peptides on the skin barrier

[0075] This embodiment uses Western blotting to detect the expression of Loricrin, Involucrin, Filagrin, and Aquaporin-3 in HACAT cells. Cells were treated with GPH, IL, FGP, and LGPL for 24 h, respectively, followed by digestion, centrifugation, and cell collection. Total protein concentration was extracted from each group using RIPA protein lysis buffer. 20 mg of total protein from each group was loaded for SDS-PAGE gel electrophoresis. After 2 h, the sample was transferred to a PVDF membrane, blocked with 5% BSA for 1 h, and then incubated with primary antibodies against Loricrin, Involucrin, Filagrin, and Aquaporin-3 overnight at 4°C. After primary antibody recovery, the cells were washed three times with TBST and incubated with rabbit anti / mouse anti-IgG secondary antibody for 1 h at room temperature. After incubation, the cells were washed three times with TBST and detected using fluorescence imaging. The relative expression levels of each target protein were analyzed using ImageJ software.

[0076] As shown in Figure 6, compared with the control group, the expression levels of four proteins—Loricrin, Involucrin, Filaggrin, and Aquaporin-3—were increased after intervention with GPH, IL, FGP, and LGPL. The protein expression levels of Loricrin, Filaggrin, and Aquaporin-3 were all higher after intervention with IL, FGP, and LGPL than after GPH. These results indicate that all four peptides—GPH, IL, FGP, and LGPL—can increase the expression levels of moisturizing proteins in the skin barrier, with IL, FGP, and LGPL showing the best effects. This suggests that IL, FGP, and LGPL can effectively protect the skin barrier and maintain skin's radiance and hydration.

[0077] Example 7: Effects of peptides on collagen protein synthesis

[0078] 1. Determination of type I collagen expression

[0079] Based on an established MSF cell oxidative damage model, the effects of GPH, IL, FGP, and LGPL on CO-1 expression in UV-induced MSF cells were investigated by Western blotting. After 70 min of UV induction, MSF cells in each group were treated with GPH, IL, FGP, and LGPL for 24 h, respectively. Cells were then digested, centrifuged, and collected. Proteins were extracted from cells using RIPA lysis and analyzed by Western blotting using fluorescence imaging. The relative expression levels of each target protein were analyzed using ImageJ software.

[0080] The results are shown in Figure 7. Compared with the control group, the content of type I collagen in the model group cells irradiated by UV was significantly reduced. After intervention with GPH, IL, FGP, and LGPL, the expression level of type I collagen in the cells increased, with LGPL showing the most significant effect, followed by IL, GPH, and FGP. The results indicate that the three peptides IL, FGP, and LGPL screened in this study have collagen synthesis efficacy comparable to the positive control GPH.

[0081] 2. Determination of collagenase inhibition rate

[0082] Collagenase, a type of protease in molecular biology, breaks down collagen. Collagen determines the properties of connective tissue, maintaining the skin's resilience and firmness. High collagen content in the skin results in plump and firm skin, while a lack of collagen leads to loose and inelastic skin.

[0083] Collagenase was dissolved in 0.1M Tris-HCl buffer (pH 7.5). To measure collagenase inhibitory activity, 150 μL of collagenase and 250 μL of 0.1M Tris-HCl buffer (pH 7.5) containing the substrate collagenase were added, followed by the addition of 100 μL of sample containing 4 mM CaCl2. The mixture was incubated in the dark at 25°C for 20 min. Finally, 0.5 mL of 6% citric acid was added to terminate the reaction, and 1.5 mL of ethyl acetate was added to separate the reaction mixture. The absorbance of the supernatant was measured at 320 nm using a UV spectrophotometer. The collagenase inhibitory activity was determined as follows:

[0084] Among them, samples OD Values ​​and sample blanks OD The values ​​represent the optical density of the sample in the presence and absence of the blank, respectively. OD The value represents the optical density when collagenase is absent.

[0085] The results are shown in Figure 8. The IC50 values ​​of GPH, IL, FGP, and LGPL for inhibiting collagenase activity are also shown. 50The values ​​were 3.42, 3.27, 2.70, and 3.11, respectively, indicating that all four peptides have a certain inhibitory effect on collagenase activity, reducing the degradation of collagen in skin fibroblasts. Furthermore, compared to GPH, IL, FGP, and LGPL have higher inhibition rates of collagenase activity. Therefore, IL, FGP, and LGPL can more effectively maintain skin resilience and firmness, and delay skin aging.

[0086] Example 8: Effects of peptides on collagen degradation

[0087] Based on an established MSF cell oxidative damage model, this study investigated the effects of GPH, IL, FGP, and LGPL on the expression of MMP1, MMP2, and MMP9 in UV-induced MSF cells using Western blotting. After 70 min of UV induction, MSF cells in each group were treated with GPH, IL, FGP, and LGPL for 24 h, respectively. Cells were then digested, centrifuged, and collected. Proteins were extracted from cells using RIPA lysis and analyzed by Western blotting using fluorescence imaging. The relative expression levels of each target protein were analyzed using ImageJ software.

[0088] The results showed that the expression level of MMP in the UV-induced group was significantly increased compared with the control group, indicating that the model was successfully established. All four peptides in the experimental group significantly inhibited the expression of MMP1, MMP2, and MMP9 proteins, and IL, FGP, and LGPL all showed higher inhibitory effects on MMP than GPH, with LGPL exhibiting the strongest inhibitory effect on MMP (Figure 9).

[0089] Example 9: Effects of peptides on fibroblast repair activity

[0090] Experimental groups: blank group (HaCaT cells without irradiation + serum-free culture medium), model group (HaCaT cells UV irradiated + serum-free culture medium), experimental group (HaCaT cells UV irradiated + 20 μM sample solution prepared with serum-free culture medium).

[0091] First, draw three evenly spaced horizontal lines on the bottom of the 6-well plate using a marker. Then, inoculate HACAT into the 6-well plate (6 × 10⁻⁶). 5 Cells / well, 2 mL culture medium / well. When the cell coverage reaches 90%-100%, replace the serum-free culture medium according to the experimental group and treat for 3 hours. Use a sterile pipette tip to make straight lines of similar thickness on the bottom of the 6-well plate. Wash with PBS 3 times to remove suspended cells, and then replace with new serum-free culture medium according to the experimental group. Photograph the cell migration status in the same field of view at 0, 6, 12, 24, 36 and 48 hours, and calculate the scratch area using ImageJ software.

[0092] In the cell scratch assay, as shown in Figure 10, compared with the control group, cells showed a significant migration trend after intervention with IL, FGP, LGPL, and GPH. The cell migration rates in the IL, FGP, and LGPL groups were all higher than those in the GPH group, with a significant difference between the IL and LGPL groups. These results confirm that IL, FGP, and LGPL have the effects of promoting cell proliferation, increasing cell migration rate, and repairing cell damage.

[0093] In summary, the following conclusions can be drawn from the experiments: (1) This application found that IL, FGP, and LGPL can improve cell survival rate and have a protective effect on cells; (2) This application found that IL, FGP, and LGPL can inhibit intracellular lipid oxidation and oxidative stress, thereby protecting cells from oxidative damage; (3) This application found that IL, FGP, and LGPL can significantly increase the expression of intracellular barrier moisturizing and hydrating proteins, protect the skin barrier, and lock in skin moisture; (4) This application found that IL, FGP, and LGPL have a significant inhibitory effect on the increase in expression of MMP1, MMP2, and MMP9 proteins in UV-induced MSF cells, and the effect is stronger than that of GPH; (5) This application found that IL, FGP, and LGPL can significantly inhibit the decrease in collagen content caused by UV; (6) This application found that IL, FGP, and LGPL can promote cell proliferation and increase cell migration rate, thereby playing a role in repairing skin damage.

[0094] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. Tilapia skin peptide with anti-aging activity, wherein the tilapia skin peptide is isolated and identified from tilapia skin enzyme products, and the tilapia skin peptide is IL, FGP or LPGL.

2. The Tilapia skin peptide according to claim 1, wherein, The preparation method of the tilapia skin enzymatic hydrolysate is as follows: Take an appropriate amount of frozen tilapia skin, thaw it with water, then soak it in 5%-10% NaOH to remove impurities. Rinse it several times with clean water until the pH of the washing water is neutral. Add 0.05%-2% alkaline protease and enzymatically hydrolyze for 2-8 hours. Then, inactivate the enzyme in a boiling water bath. Take the enzymatic hydrolysate and pass it through a 200-mesh silk cloth to remove impurities. Filter to remove suspended impurities, then centrifuge at 4°C, take the supernatant, and freeze-dry it to obtain the tilapia skin enzymatic hydrolysate.

3. The method for preparing tilapia skin peptide according to claim 1 or claim 2, wherein the tilapia skin peptide is obtained by enzymatic hydrolysis and separation from tilapia skin.

4. The method for preparing tilapia skin peptide according to claim 1 or claim 2, wherein the tilapia skin peptide is prepared by solid-phase synthesis.

5. Use of the tilapia skin peptide according to claim 1 or claim 2 in the preparation of anti-aging related products.

6. Use according to claim 5, wherein, The product is an oral or topical product.

7. Use according to claim 6, wherein, The products mentioned are pharmaceuticals, functional foods, health products, beverages, nutritional supplements, or cosmetics.

8. Use according to claim 7, wherein, The products are oral solutions, tablets, pills, liquid suspensions, injections, granules, powders, capsules, beverages, energy bars, chewing gum, or candy.

9. Use according to claim 7, wherein, The products mentioned are toners, lotions, serums, creams, or masks.

10. Use according to claim 5, wherein, The product has a protective effect against UV-induced cell damage, possesses antioxidant activity, repairs damaged cells, protects the skin barrier, and delays skin aging.

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