A composition for improving skin immunity and skin barrier function, and a preparation method and application thereof

Abstract

The present application relates to a kind of compositions for improving skin immunity and skin barrier function and its preparation method and application, belong to cosmetic technical field.The composition for improving skin immunity and skin barrier function, including the weight ratio of 1-4:0.5 aspartic acid polysaccharide and aspartic acid active peptide;Wherein, the aspartic acid polysaccharide can promote fibroblast proliferation, macrophage secretion anti-inflammatory factor, can enhance the active defense ability of skin, and have significant antioxidant capacity;The aspartic acid active peptide has the effect of promoting human skin fibroblast activity, cell proliferation, resisting oxidative damage.The aspartic acid polysaccharide and aspartic acid active peptide are compounded according to specific amount ratio in the present application, can synergistically promote the secretion of barrier repair related protein (i.e.silk aggregate protein and shikin protein), effectively regulate skin immune homeostasis, improve skin defense and barrier repair capacity.

Description

Technical Field

[0001] This invention relates to the field of cosmetic technology, and in particular to a composition for improving skin immunity and skin barrier function, its preparation method, and its application. Background Technology

[0002] As the largest organ in the human body, the skin plays a crucial role in maintaining the homeostasis between the body and the external environment. It not only forms the first physical barrier against external pollutants, ultraviolet radiation, and microbial infections, but also possesses active immunomodulatory functions and interacts closely with the systemic immune system. Imbalances in the local immune state of the skin can induce various clinical skin manifestations and related diseases. The skin immune system comprises two core components: cellular immunity and humoral immunity. Cellular immunity is formed through the interaction of various immune cells distributed in the epidermis and dermis (such as Langerhans cells, T cells, and macrophages); humoral immunity is mainly mediated by immunologically active molecules such as antibodies, complement, and various cytokines. Both work closely together in the skin microenvironment to maintain skin immune homeostasis and defense functions. Further research indicates that various external physical, chemical, and biological factors (such as ultraviolet radiation, pollutants, pathogens, and allergens) can significantly impact the overall physiological state and pathological processes of the skin by regulating the response of the skin's immune system.

[0003] In current research on skin health, maintaining and actively regulating skin immune homeostasis has become a key issue. The skin is not only an important physical barrier but also an active interface for immune responses; its immune function directly affects barrier integrity, tissue homeostasis, and defense capabilities. Developing products with targeted immunomodulatory functions has significant research and clinical application value for enhancing skin defense, improving physiological conditions, and preventing related diseases. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a composition for improving skin immunity and skin barrier function, as well as its preparation method and application.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows: In a first aspect, the present invention provides a composition for improving skin immunity and skin barrier function, comprising asparagine polysaccharide and asparagine active peptide in a weight ratio of 1-4:0.5; The asparagine polysaccharide is obtained by using asparagus as raw material and undergoing enzymatic hydrolysis and electron beam irradiation treatment, resulting in an asparagine polysaccharide with a molecular weight of <3KDa. The aspartic active peptide may include, but is not limited to, short peptides with the following amino acid sequences: FF, FW, WFW, MPF, FFPF, FPF, WPF, WFL, LPF, FPL, LFP, FP, GFL, FLG, LGF, APLF.

[0006] The composition for improving skin immunity and skin barrier function provided by this invention includes asparagus polysaccharides prepared by optimizing enzyme types, enzymatic hydrolysis methods, electron beam irradiation parameters, and the molecular weight range of asparagus polysaccharides. Enzymatic extraction can separate and hydrolyze the polysaccharides in asparagus to obtain oligosaccharide fragments. Electron beam irradiation treatment can improve the functional properties and bioactivity of polysaccharides, but different irradiation doses have different effects on polysaccharides. This invention obtains asparagus polysaccharides with a specific molecular weight range after specific electron beam irradiation and screening. The obtained asparagus polysaccharides can promote fibroblast proliferation and macrophage secretion of anti-inflammatory factors, thereby improving the basic immune level of macrophages and enhancing the skin's active defense capability, while also having significant antioxidant capacity. The asparagus active peptides can enhance the vitality of human skin fibroblasts, promote cell proliferation, and resist oxidative damage. This invention combines the asparagus polysaccharides and asparagus active peptides in a specific ratio to synergistically promote the secretion of barrier repair-related proteins (i.e., filaggrin and acetolin), effectively regulating skin immune homeostasis and enhancing skin defense and barrier repair capabilities.

[0007] Furthermore, the preparation method of the asparagus polysaccharide includes the following steps: S1. Crush and sieve the dried asparagus to obtain asparagus powder, add pure water, adjust the pH of the system to 6.0-7.0, add cellulase and α-galactosidase, stir the reaction, filter, and obtain filter residue and first enzymatic hydrolysate; S2. Add pure water to the filter residue obtained in S1, adjust the pH of the system to 5.0-7.0, add papain, stir the reaction, filter, and obtain the second enzymatic hydrolysate; S3. Combine the first and second enzyme hydrolysates, inactivate the enzyme, concentrate, precipitate with ethanol, centrifuge to obtain the precipitate, dry, and pulverize into powder to obtain crude asparagus polysaccharide. S4. Dissolve crude asparagus polysaccharide in pure water, irradiate with an electron beam, separate the irradiated liquid by membrane separation, collect the permeate with a molecular weight cutoff of <3 kDa, freeze-dry to obtain asparagus polysaccharide.

[0008] Preferably, the amount of pure water added in steps S1 and S2 is 5-10 times the mass of the asparagus powder.

[0009] Preferably, in step S1, the amount of cellulase added is 1%-3% of the mass of asparagus powder, the amount of α-galactosidase added is 2%-4% of the mass of asparagus powder, and the stirring reaction is carried out at 45-50℃ and 300-500 r / min for 60-100 min. In step S2, the amount of pure water added is 5-10 times the mass of asparagus powder, the amount of papain added is 1%-5% of the mass of asparagus powder, and the stirring reaction is carried out at 55-60℃ and 300-500 r / min for 60-100 min.

[0010] Preferably, the filtration in steps S1 and S2 is performed using a 200-mesh filter cloth.

[0011] Preferably, the enzyme inactivation in step S3 is performed by maintaining the enzyme in a 90°C water bath for 8-10 minutes.

[0012] Preferably, the concentration in step S3 is vacuum concentration to 1 / 5-1 / 8 of the original volume; the ethanol precipitation is the addition of ethanol to the concentrate until the final ethanol concentration in the system reaches 80% v / v and then standing for 10-16 h; the centrifugation in step S3 is centrifugation at 8000-10000 r / min for 15-30 min.

[0013] Preferably, the drying in step S3 is drying at 50-60°C to a constant weight.

[0014] Preferably, the mass ratio of crude asparagus polysaccharide to pure water in step S4 is 1:3-8.

[0015] Preferably, the electron beam irradiation in step S4 is carried out at a temperature of 40-50°C, an irradiation dose of 60-80 kGy, and a time of 10-30 s.

[0016] Furthermore, the preparation method of the aspartic active peptide includes the following steps: (1) Crush the dried asparagus tuber to obtain asparagus powder, add pure water, stir and soak at 4-10℃ for 20-50 min, and treat with pulse ultrasound to obtain pretreated material; (2) Adjust the pH of the pretreated material to 7.2-8.5, add trypsin, carry out the first stirring reaction, filter with filter cloth to obtain filter residue and first peptide filtrate; take the filter residue, add pure water, adjust the pH to 6.2-7.5, add papain and neutral protease, carry out the second stirring reaction, filter with filter cloth to obtain second peptide filtrate; combine the two peptide filtrates, inactivate enzymes, filter by suction to obtain clear filtrate; (3) The clarified filtrate is concentrated, precipitated with ethanol, and centrifuged to obtain the supernatant. After removing the ethanol from the supernatant, the permeate with a molecular weight <5KDa is retained using an ultrafiltration membrane system and the permeate is collected. (4) The permeate is freeze-dried under vacuum to obtain aspartic active peptide.

[0017] Preferably, the amount of pure water added in step (1) is 5-10 times the mass of the asparagus powder, the stirring and soaking speed is 300-500 r / min, and the conditions for pulse ultrasonic treatment are: power 300W, frequency 20~40kHz, pulse mode is 3s working and 3s intermittent, and ultrasonic treatment time is 10-30min.

[0018] Preferably, in step (2), the amount of trypsin added is 1%-4% of the mass of asparagus powder, the temperature of the first stirring reaction is 45-55℃, the rotation speed is 300-500r / min, and the time is 60min, the amount of pure water added is 5-10 times the mass of asparagus powder, the amount of papain added is 1%-2% of the mass of asparagus powder, the amount of neutral protease added is 0.5%-1.5% of the mass of asparagus powder, and the temperature of the second stirring reaction is 45-55℃, the rotation speed is 300-500r / min, and the time is 60min.

[0019] Preferably, the filter cloth filtration in step (2) is filtration with a 100-mesh filter cloth, the enzyme inactivation is carried out by maintaining the filter cloth in a 90°C water bath for 8-10 minutes, and the vacuum filtration is carried out by using a Buchner funnel with a 0.45μm microporous filter membrane.

[0020] Preferably, the concentration in step (3) is vacuum concentration to 1 / 5-1 / 10 of the original volume.

[0021] Preferably, the ethanol precipitation in step (3) is carried out by slowly adding 95% v / v ethanol to the concentrate while stirring at a speed of 120-150 r / min until the final concentration of ethanol in the system reaches 85% v / v, and then letting it stand at 4°C for 10-16 h.

[0022] Preferably, the centrifugation in step (3) is centrifugation at 8000-9000 r / min for 20-30 min, and the removal of ethanol from the supernatant is vacuum concentration at room temperature.

[0023] Preferably, in step (3), an ultrafiltration membrane system is used to retain permeate with a molecular weight of <1 kDa.

[0024] In a second aspect, the present invention provides the use of the composition described in the first aspect in the preparation of products that improve skin immunity and skin barrier function.

[0025] Furthermore, the product in question is a cosmetic.

[0026] Thirdly, the present invention provides a cosmetic that improves skin immunity and skin barrier function, comprising the composition described in the first aspect.

[0027] Furthermore, the composition accounts for 0.1%-5% of the total mass of the cosmetic.

[0028] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention provides a composition for improving skin immunity and skin barrier function, comprising asparagine polysaccharide and asparagine active peptides in a weight ratio of 1-4:0.5. The asparagine polysaccharide is prepared by optimizing enzyme types, enzymatic hydrolysis methods, electron beam irradiation parameters, and the molecular weight range of the asparagine polysaccharide. It can promote fibroblast proliferation and macrophage secretion of anti-inflammatory factors, thereby improving the basic immune level of macrophages and enhancing the skin's active defense capability, while also exhibiting significant antioxidant capacity. The asparagine active peptides enhance the vitality of human skin fibroblasts, promote cell proliferation, and resist oxidative damage. This invention combines the asparagine polysaccharide and asparagine active peptides to obtain a composition. Within a specific dosage range, the asparagine polysaccharide and asparagine active peptides in the composition can synergistically enhance the secretion of barrier repair-related proteins (figrin and chrysophanin), effectively regulating skin immune homeostasis and improving skin defense and barrier repair capabilities. Detailed Implementation

[0029] To better illustrate the purpose, technical solution, and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments.

[0030] In the following embodiments: Cellulase: Purchased from Shanghai Yuanye Biotechnology Co., Ltd., product number: S10041, enzyme activity: 50U / mg; α-Galactosidase: Brand: Aladdin; Product No.: G304917-25g; Enzyme Activity: 2000U / g; Papain: Purchased from Beijing Innochem Technology Co., Ltd., product number: B99890, enzyme: 800U / mg; β-Galactosidase: Brand: Aladdin, Product No.: G128642-5KU, Enzyme Activity: 50 U / mg; The preparation method of aspartic active peptides includes the following steps: (1) The dried asparagus root is crushed to obtain asparagus powder, pure water is added, and the mixture is stirred and soaked at 4°C for 35 minutes. The mixture is then subjected to pulsed ultrasonic treatment to obtain pretreated material. (2) Adjust the pH of the pretreated material to 8.0, add trypsin, carry out the first stirring reaction, filter with filter cloth to obtain filter residue and the first peptide filtrate; take the filter residue, add pure water, adjust the pH to 6.5, add papain and neutral protease, carry out the second stirring reaction, filter with filter cloth to obtain the second peptide filtrate; combine the two peptide filtrates, inactivate the enzyme, filter by suction to obtain clear filtrate; (3) The clarified filtrate is concentrated, precipitated with ethanol, and centrifuged to obtain the supernatant. After removing the ethanol from the supernatant, the permeate with a molecular weight <1 kDa is retained using an ultrafiltration membrane system and the permeate is collected. (4) The permeate was freeze-dried under vacuum until constant weight to obtain aspartic active peptide; In step (1), the amount of pure water added is 8 times the mass of asparagus powder; the stirring and soaking speed is 400 r / min; the conditions for pulsed ultrasonic treatment are: power 300 W, frequency 30 kHz, pulse mode 3s working, 3s intermittent, and total ultrasonic treatment time 20 min; in step (2), the amount of trypsin added is 2.5% of the mass of asparagus powder; the temperature of the first stirring reaction is 50℃, the speed is 400 r / min, and the time is 60 min; the amount of pure water added is 8 times the mass of asparagus powder; the amount of papain added is 1.5% of the mass of asparagus powder; the amount of neutral protease added is 1% of the mass of asparagus powder; and the temperature of the second stirring reaction is... The temperature is 50℃, the rotation speed is 400r / min, and the time is 60min. The filter cloth filtration is performed using a 100-mesh filter cloth. The enzyme inactivation is performed by maintaining the solution in an 85℃ water bath for 9min. The vacuum filtration is performed using a Buchner funnel with a 0.45μm microporous membrane. In step (3), the concentration is performed by vacuum concentration at room temperature to 1 / 8 of the original volume. The ethanol precipitation is performed by slowly adding 95% v / v ethanol to the concentrate while stirring at a rotation speed of 130r / min until the final ethanol concentration in the system reaches 85% v / v, and then letting it stand at 4℃ for 12h. The centrifugation is performed by centrifugation at 8500r / min for 25min. The removal of ethanol from the supernatant is performed by vacuum concentration at room temperature.

[0031] The short peptides with high activity and high content in the aspartic active peptides may include, but are not limited to: FF, FW, WFW, MPF, FFPF, FPF, WPF, WFL, LPF, FPL, LFP, FP, GFL, FLG, LGF, and APLF.

[0032] Unless otherwise specified, all other materials and reagents used in the examples are commercially available.

[0033] Example 1 This embodiment provides an asparagine polysaccharide, the preparation method of which includes the following steps: S1. Pulverize the dried asparagus and pass it through a 100-mesh sieve to obtain asparagus powder. Add pure water to adjust the pH of the system to 6.5. Add cellulase and α-galactosidase, stir the reaction, filter, and obtain filter residue and first enzymatic hydrolysate. S2. Add pure water to the filter residue obtained in S1, adjust the pH of the system to 6.0, add papain, stir the reaction, filter, and obtain the second enzymatic hydrolysate; S3. Combine the first and second enzyme hydrolysates, inactivate the enzyme, concentrate, precipitate with ethanol, centrifuge to obtain the precipitate, dry, and pulverize into powder to obtain crude asparagus polysaccharide. S4. Dissolve crude asparagus polysaccharide in pure water, irradiate with an electron beam, separate the irradiated liquid by membrane separation, collect the permeate with a molecular weight cutoff of <3 kDa, freeze dry, and obtain asparagus polysaccharide 1. In step S1, the amount of pure water added is 8 times the mass of asparagus powder, the amount of cellulase added is 2% of the mass of asparagus powder, the amount of α-galactosidase added is 3% of the mass of asparagus powder, the stirring reaction is carried out at 48°C and 400 r / min for 80 min, and the filtration is carried out using a 200 mesh filter cloth. In step S2, the amount of pure water added is 8 times the mass of asparagus powder, the amount of papain added is 2.5% of the mass of asparagus powder, the stirring reaction is carried out at 58°C and 400 r / min for 80 min, and the filtration is carried out using a 200 mesh filter cloth. In step S3, enzyme inactivation is performed by maintaining the solution in a 90°C water bath for 9 minutes; concentration is performed by vacuum concentration to 1 / 6 of the original volume; ethanol precipitation is performed by adding anhydrous ethanol to the concentrate until the final ethanol concentration in the system reaches 80% v / v, and then allowing it to stand for 12 hours; centrifugation is performed by centrifugation at 9000 r / min for 20 minutes; and drying is performed by drying at 55°C to constant weight. In step S4, the mass ratio of crude asparagus polysaccharide to pure water is 1:5; the electron beam irradiation temperature is 45℃, the irradiation dose is 70kGy, and the time is 20s.

[0034] This embodiment also provides a composition comprising asparagine polysaccharide 1 and asparagine active peptide in a mass ratio of 2:0.5.

[0035] Example 2 This embodiment provides an asparagine polysaccharide, the preparation method of which includes the following steps: S1. Pulverize the dried asparagus and pass it through a 100-mesh sieve to obtain asparagus powder. Add pure water to adjust the pH of the system to 6.0. Add cellulase and α-galactosidase, stir the reaction, filter, and obtain filter residue and first enzymatic hydrolysate. S2. Add pure water to the filter residue obtained in S1, adjust the pH of the system to 5.0, add papain, stir the reaction, filter, and obtain the second enzymatic hydrolysate; S3. Combine the first and second enzyme hydrolysates, inactivate the enzyme, concentrate, precipitate with ethanol, centrifuge to obtain the precipitate, dry, and pulverize into powder to obtain crude asparagus polysaccharide. S4. Dissolve crude asparagus polysaccharide in pure water, irradiate with an electron beam, separate the irradiated liquid by membrane separation, collect the permeate with a molecular weight cutoff of <3 kDa, freeze dry, and obtain asparagus polysaccharide 2. In step S1, the amount of pure water added is 10 times the mass of asparagus powder, the amount of cellulase added is 3% of the mass of asparagus powder, the amount of α-galactosidase added is 2% of the mass of asparagus powder, the stirring reaction is carried out at 45°C and 300 r / min for 100 min, and the filtration is carried out using a 200 mesh filter cloth. In step S2, the amount of pure water added is 10 times the mass of asparagus powder, the amount of papain added is 5% of the mass of asparagus powder, the stirring reaction is carried out at 55°C and 300 r / min for 100 min, and the filtration is carried out using a 200 mesh filter cloth. In step S3, enzyme inactivation is performed by maintaining the solution in a 90°C water bath for 9 minutes; concentration is performed by vacuum concentration to 1 / 5 of the original volume; ethanol precipitation is performed by adding anhydrous ethanol to the concentrate until the final ethanol concentration in the system reaches 80% v / v, and then allowing it to stand for 12 hours; centrifugation is performed by centrifugation at 10000 r / min for 15 minutes; and drying is performed by drying at 60°C to constant weight. In step S4, the mass ratio of crude asparagus polysaccharide to pure water is 1:3; the electron beam irradiation temperature is 40℃, the irradiation dose is 60kGy, and the time is 30s.

[0036] This embodiment also provides a composition comprising asparagine polysaccharide 2 and asparagine active peptide in a mass ratio of 1:0.5.

[0037] Example 3 This embodiment provides an asparagine polysaccharide, the preparation method of which includes the following steps: S1. Pulverize the dried asparagus and pass it through a 100-mesh sieve to obtain asparagus powder. Add pure water to adjust the pH of the system to 7.0. Add cellulase and α-galactosidase, stir the reaction, filter, and obtain filter residue and first enzymatic hydrolysate. S2. Add pure water to the filter residue obtained in S1, adjust the pH of the system to 7.0, add papain, stir the reaction, filter, and obtain the second enzymatic hydrolysate; S3. Combine the first and second enzyme hydrolysates, inactivate the enzyme, concentrate, precipitate with ethanol, centrifuge to obtain the precipitate, dry, and pulverize into powder to obtain crude asparagus polysaccharide. S4. Dissolve crude asparagus polysaccharide in pure water, irradiate with an electron beam, separate the irradiated liquid by membrane separation, collect the permeate with a molecular weight cutoff of <3 kDa, freeze dry, and obtain asparagus polysaccharide 3. In step S1, the amount of pure water added is 5 times the mass of asparagus powder, the amount of cellulase added is 1% of the mass of asparagus powder, the amount of α-galactosidase added is 4% of the mass of asparagus powder, the stirring reaction is carried out at 50°C and 500 r / min for 60 min, and the filtration is carried out using a 200 mesh filter cloth. In step S2, the amount of pure water added is 5 times the mass of asparagus powder, the amount of papain added is 1% of the mass of asparagus powder, the stirring reaction is carried out at 60°C and 500 r / min for 60 min, and the filtration is carried out using a 200 mesh filter cloth. In step S3, enzyme inactivation is performed by maintaining the solution in a 90°C water bath for 9 minutes; concentration is performed by vacuum concentration to 1 / 8 of the original volume; ethanol precipitation is performed by adding anhydrous ethanol to the concentrate until the final ethanol concentration in the system reaches 80% v / v, and then allowing it to stand for 12 hours; centrifugation is performed by centrifugation at 8000 r / min for 30 minutes; and drying is performed by drying at 50°C to constant weight. In step S4, the mass ratio of crude asparagus polysaccharide to pure water is 1:8; the electron beam irradiation temperature is 50℃, the irradiation dose is 80kGy, and the time is 10s.

[0038] This embodiment also provides a composition comprising asparagine polysaccharide 3 and asparagine active peptide in a mass ratio of 4:0.5.

[0039] Comparative Example 1 This comparative example provides an asparagus polysaccharide. The preparation method of the asparagus polysaccharide differs from that of Example 1 in that the order of steps S1 and S2 is adjusted, specifically as follows: S1. Pulverize the dried asparagus and pass it through a 100-mesh sieve to obtain asparagus powder. Add pure water to adjust the pH of the system to 6.0. Add papain, stir the reaction, filter, and obtain filter residue and first enzymatic hydrolysate. S2. Add pure water to the filter residue obtained in S1, adjust the pH of the system to 6.5, add cellulase and α-galactosidase, stir the reaction, filter, and obtain the second enzymatic hydrolysate; In step S1, the amount of pure water added is 8 times the mass of asparagus powder, the amount of papain added is 2.5% of the mass of asparagus powder, the stirring reaction is carried out at 58℃ and 400 r / min for 80 min, and the filtration is carried out using a 200-mesh filter cloth; in step S2, the amount of pure water added is 8 times the mass of asparagus powder, the amount of cellulase added is 2% of the mass of asparagus powder, the amount of α-galactosidase added is 3% of the mass of asparagus powder, the stirring reaction is carried out at 48℃ and 400 r / min for 80 min, and the filtration is carried out using a 200-mesh filter cloth. The remaining steps and parameters are the same as in Example 1, and asparagine 1' is prepared.

[0040] This comparative example also provides a composition comprising asparagine polysaccharide 1' and asparagine active peptide in a mass ratio of 2:0.5.

[0041] Comparative Example 2 This comparative example provides an asparagus polysaccharide. The preparation method of the asparagus polysaccharide differs from that of Example 1 in that it does not use papain for enzymatic hydrolysis, but only cellulase and α-galactosidase are used for enzymatic hydrolysis. Specifically: S1. Pulverize the dried asparagus and pass it through a 100-mesh sieve to obtain asparagus powder. Add pure water to adjust the pH of the system to 6.5. Add cellulase and α-galactosidase, stir the reaction, filter, and obtain filter residue and enzymatic hydrolysate. S2. After inactivating the enzyme in the enzymatic hydrolysate, the solution is concentrated, precipitated with ethanol, and centrifuged to obtain the precipitate. The precipitate is then dried, pulverized into powder, and obtained asparagus crude polysaccharide. S3. Dissolve crude asparagus polysaccharide in pure water, irradiate with an electron beam, separate the irradiated liquid by membrane separation, collect the permeate with a molecular weight cutoff of <3 kDa, freeze dry, and obtain asparagus polysaccharide 1. In step S1, the amount of pure water added is 8 times the mass of asparagus powder, the amount of cellulase added is 3% of the mass of asparagus powder, the amount of α-galactosidase added is 4.5% of the mass of asparagus powder, the stirring reaction is carried out at 48°C and 400 r / min for 160 min, and the filtration is carried out using a 200 mesh filter cloth. The parameters in steps S2 and S3 are the same as in Example 1, and asparagine 2' is prepared.

[0042] This comparative example also provides a composition comprising asparagine 2' and asparagine active peptide in a mass ratio of 2:0.5.

[0043] Comparative Example 3 This comparative example provides an asparagus polysaccharide. The preparation method of the asparagus polysaccharide differs from that of Example 1 in that it does not use cellulase and α-galactosidase for enzymatic hydrolysis, but only papain is used for enzymatic hydrolysis. Specifically: S1. Pulverize the dried asparagus and pass it through a 100-mesh sieve to obtain asparagus powder. Add pure water to adjust the pH of the system to 6.0. Add papain, stir to react, filter, and obtain the enzymatic hydrolysate. S2. After inactivating the enzyme in the enzymatic hydrolysate, the solution is concentrated, precipitated with ethanol, and centrifuged to obtain the precipitate. The precipitate is then dried, pulverized into powder, and obtained asparagus crude polysaccharide. S3. Dissolve crude asparagus polysaccharide in pure water, irradiate with an electron beam, separate the irradiated liquid by membrane separation, collect the permeate with a molecular weight cutoff of <3 kDa, freeze dry, and obtain asparagus polysaccharide 1. In step S1, the amount of pure water added is 8 times the mass of asparagus powder, the amount of papain added is 7.5% of the mass of asparagus powder, the stirring reaction is carried out at 58°C and 400 r / min for 160 min, and the filtration is carried out using a 200 mesh filter cloth. The parameters in steps S2 and S3 are the same as in Example 1, and asparagine polysaccharide 3' is prepared.

[0044] This comparative example also provides a composition comprising asparagine polysaccharide 3' and asparagine active peptide in a mass ratio of 2:0.5.

[0045] Comparative Example 4 This comparative example provides an asparagus polysaccharide. The difference between the preparation method of the asparagus polysaccharide and that of Example 1 is that in step S1, an equal amount of β-galactosidase is used instead of α-galactosidase for enzymatic hydrolysis. The remaining steps and parameters were the same as in Example 1, and asparagine 4' was prepared.

[0046] This comparative example also provides a composition comprising asparagine polysaccharide 4' and asparagine active peptide in a mass ratio of 2:0.5.

[0047] Comparative Example 5 This comparative example provides an asparagus polysaccharide. The preparation method of the asparagus polysaccharide differs from that of Example 1 in that the electron beam irradiation temperature in step S4 is 45°C, the irradiation dose is 100 kGy, and the time is 20 s. The remaining steps and parameters were the same as in Example 1, and asparagine 5' was prepared.

[0048] This comparative example also provides a composition comprising asparagine 5' and asparagine active peptide in a mass ratio of 2:0.5.

[0049] Comparative Example 6 This comparative example provides an asparagus polysaccharide. The preparation method of the asparagus polysaccharide differs from that of Example 1 in that the electron beam irradiation temperature in step S4 is 45°C, the irradiation dose is 70 kGy, and the time is 40 s. The remaining steps and parameters were the same as in Example 1, and asparagine 6' was prepared.

[0050] This comparative example also provides a composition comprising asparagine polysaccharide 6' and asparagine active peptide in a mass ratio of 2:0.5.

[0051] Comparative Example 7 This comparative example provides an asparagus polysaccharide. The difference between the preparation method of the asparagus polysaccharide and that of Example 1 is that, in step S4, after membrane separation, the permeate with a molecular weight cutoff of <1 kDa is collected. The remaining steps and parameters were the same as in Example 1, and asparagine 7' was prepared.

[0052] This comparative example also provides a composition comprising asparagine polysaccharide 7' and asparagine active peptide in a mass ratio of 2:0.5.

[0053] Comparative Example 8 This comparative example provides an asparagus polysaccharide. The difference between the preparation method of the asparagus polysaccharide and that of Example 1 is that, in step S4, after membrane separation, the permeate with a molecular weight cutoff of <5 kDa is collected. The remaining steps and parameters were the same as in Example 1, and asparagine 8' was prepared.

[0054] This comparative example also provides a composition comprising asparagine polysaccharide 8' and asparagine active peptide in a mass ratio of 2:0.5.

[0055] Comparative Example 9 This comparative example provides a composition that differs from Example 1 in that the mass ratio of asparagine polysaccharide 1 to asparagine active peptide is 1:1.

[0056] Test Example 1 1. Effects of Asparagine Polysaccharide on the Viability of Human Foreskin Fibroblasts (HFF) Human foreskin fibroblasts (HFF) are core functional cells for dermal repair, and their proliferative capacity is directly related to wound healing efficiency. This test used asparagine polysaccharides prepared in Examples 1-3 and Comparative Examples 1-8 as test samples to determine their effect on the viability of human foreskin fibroblasts.

[0057] The cell line used was human foreskin fibroblasts (HFF) (Shanghai Cell Bank, Chinese Academy of Sciences). The testing conditions were: incubator temperature 37±1℃, humidity 90±5%, carbon dioxide 5±1%. Cells were cultured and treated according to groups, followed by testing. The testing methods are as follows: (1) Sample preparation: (a) The asparagine polysaccharide prepared in Example 1 was prepared into a stock solution of 50 mg / mL using PBS, and then diluted with serum-free DMEM medium (DME101500, Jetech) to prepare sample solutions with concentrations of 0.78 mg / mL, 1.56 mg / mL, 3.12 mg / mL, 6.25 mg / mL and 12.5 mg / mL, respectively. Three parallel tubes were set up for each sample. (b) The asparagine polysaccharides prepared in Examples 1-3 and Comparative Examples 1-8 were prepared into a stock solution of 50 mg / mL using PBS, and then diluted with serum-free DMEM medium (DME101500, Jetech) to a sample solution with a concentration of 3.12 mg / mL. Three parallel tubes were set up for each sample.

[0058] (2) The cell suspension was seeded into a 96-well cell culture plate at a density of 6000 cells / well, and 100 μL of LMEM medium was added to each well. The cells were cultured for 24 h. (3) Sample feeding: Discard the original culture medium, add 100 μL of serum-free DMEM culture medium (DME101500, Jete) to the control group, add 100 μL of sample solution to each sample group, and incubate for 24 h; (4) CCK-8 test: After culturing for 24 hours, the original culture medium was discarded, and 100 μL of culture medium containing CCK-8 (B34304, Selleckchem) (DMEM medium: CCK-8 = 10:1) was added to each well. The culture was continued at 37±1℃ for 1 hour. The absorbance value was measured at a wavelength of 450 nm.

[0059] Proliferation rate = (Sample group A - Control group A) / (Control group A - Blank group A) × 100%; Note: Blank A refers to the absorbance value of cell-free medium containing 100 μL of CCK-8, used to subtract the background effect of CCK-8. The higher the proliferation rate, the stronger the promoting effect of asparagine on HFF cell proliferation. The results are average values, as shown in Table 1.

[0060] 2. Determination of the anti-inflammatory ability of asparagus polysaccharides In this test case, the asparagine polysaccharides prepared in Examples 1-3 and Comparative Examples 1-8 were used as test samples. Their anti-inflammatory ability was evaluated by measuring their effect on anti-inflammatory factors in an LPS-induced macrophage inflammation model.

[0061] Experimental model: RAW264.7 macrophages.

[0062] Experimental model culture: RAW264.7 macrophages were seeded in T75 culture flasks under the following conditions: incubator temperature 37±1℃, humidity 90±5%, carbon dioxide 5±1%. Cells were cultured and treated according to groupings, followed by testing. The testing methods are as follows: (a) Sample preparation: The asparagine polysaccharides prepared in Examples 1-3 and Comparative Examples 1-8 were diluted with DMEM medium, and the final concentration was 3.12 mg / mL.

[0063] (b) Resuscitation of RAW264.7 cells: Cell suspensions were seeded into 96-well cell culture plates at a density of 2000 cells / well. 100 μL of DMEM medium containing 10% (v / v) fetal bovine serum (FBS) + 1% (v / v) penicillin / streptomycin was added to each well, and the cells were cultured for 24 h to resuscitate.

[0064] (c) Model establishment: Cells were divided into a model blank group and a sample group. Each group was pretreated with LPS-containing medium for 12 h to establish an inflammation model.

[0065] (d) Sample preparation: Discard the cell supernatant. Add 100 μL of DMEM medium to the blank control group and 100 μL of medium containing 3.12 mg / mL of the corresponding sample solution to the sample groups. Incubate for 2 h, collect cells from each group, discard the medium, and wash twice with PBS. Add 1 mL of TRIzol lysis buffer, scrape off cells, transfer to EP tubes, and store at -80℃ for later use. Each experiment was repeated 3 times.

[0066] (e) ELISA detection of levels: The level of IL-10 in RAW264.7 cells was detected using an interleukin-10 (IL-10) ELISA kit.

[0067] Calculate the promotion rate: Promotion rate = [(X sample group - X model blank group) / X model blank group)] × 100%; The higher the rate of promotion of anti-inflammatory factors, the stronger the anti-inflammatory ability of asparagus polysaccharide. The calculated results are averaged, as shown in Table 2.

[0068] Results analysis: The effects of the asparagine polysaccharide prepared in Example 1 on the proliferation of HFF cells at different concentrations are shown in Table 1. The proliferation rate of HFF cells by different concentrations of asparagine polysaccharide showed a normal distribution, and the asparagine polysaccharide at a concentration of 3.12 mg / mL had the best proliferation-promoting effect on HFF cells.

[0069] Table 1. Results of the proliferation-promoting effect of different concentrations of asparagine on HFF cells. Concentration (mg / mL) Proliferation rate (%) 0.78 4.2 1.56 56.1 3.12 60.9 6.25 43.4 12.5 50.0 As shown in Table 2, the proliferation rate and IL-10 promotion rate of Examples 1-3 indicate that the asparagus polysaccharide provided by this invention can improve cell viability, effectively promote HFF cell proliferation, and simultaneously promote the secretion of the anti-inflammatory factor IL-10 within macrophages, thereby improving the basic immune level of macrophages, enhancing the skin's active defense and anti-inflammatory capabilities, and repairing the skin barrier. Analysis of the data from Comparative Examples 1-8 and Example 1 shows that the activity of the asparagus polysaccharide prepared in Comparative Examples 1-8 is far less than that of the asparagus polysaccharide in Example 1. The differences between Comparative Examples 1-4 and Example 1 lie in the enzymatic hydrolysis sequence and the type of enzyme used during the preparation of the asparagus polysaccharide; the differences between Comparative Examples 5-6 and Example 1 lie in the electron beam irradiation parameters; and the differences between Comparative Examples 7-8 and Example 1 lie in the molecular weight cutoff. This indicates that the enzymatic hydrolysis sequence, the type of enzyme used, the electron beam irradiation parameters, and the molecular weight cutoff all significantly affect the performance of the asparagus polysaccharide during its preparation.

[0070] Table 2 Results of proliferation promotion rate and anti-inflammatory factor promotion rate Group Proliferation rate (%) IL-10 promotion rate (%) Example 1 60.9 46.3 Example 2 52.1 42.6 Example 3 54.4 45.1 Comparative Example 1 40.8 35.2 Comparative Example 2 35.6 31.5 Comparative Example 3 28.2 20.3 Comparative Example 4 30.5 25.1 Comparative Example 5 31.9 26.8 Comparative Example 6 38.4 34.0 Comparative Example 7 26.7 18.4 Comparative Example 8 37.2 32.9 Test Example 2 In this test example, the asparagine polysaccharides prepared in Examples 1-3 and Comparative Examples 1-8 were used as test samples, and their antioxidant capacity was evaluated by measuring the DPPH free radical scavenging rate.

[0071] Experimental methods: (1) Reagent preparation: Preparation of DPPH solution: Weigh 4 mg of DPPH powder, dissolve it in 60% v / v ethanol aqueous solution, and make up to 100 mL to prepare a DPPH solution with a concentration of 40 mg / L. Store in the dark. Sample solution preparation: Using the asparagine polysaccharides prepared in Examples 1-3 and Comparative Examples 1-8 as samples, dissolve the corresponding samples in 60% v / v ethanol aqueous solution and make up to volume to prepare a sample solution with a concentration of 5 mg / mL. (2) Experimental Groups: Blank control group (A0): 2 mL sample solution + 2 mL 60% v / v ethanol aqueous solution; Sample group (A1): 2 mL sample solution + 2 mL DPPH solution; Sample matrix group (A2): 2 mL DPPH solution + 2 mL 60% v / v ethanol aqueous solution; Reaction: After mixing the groups evenly, let them stand in the dark for 30 min, centrifuge at 5000 r / min for 10 min, take the supernatant, and measure the absorbance at a wavelength of 517 nm.

[0072] (3) Parallel experiments and replication: Three parallel tubes were set up for each sample, and the average value of the results was taken.

[0073] (4) Data calculation and result analysis DPPH radical scavenging rate formula: DPPH radical scavenging rate (%) = [1 − (A1 − A0) / A2] × 100%; A higher DPPH free radical scavenging rate indicates a better antioxidant effect.

[0074] The results are shown in Table 3. The free radical scavenging rates of the asparagus polysaccharides in Examples 1-3 reached 88.3%-91.6%, indicating that the asparagus polysaccharides provided by this invention have significant antioxidant effects. Comparing the results of Comparative Examples 1-8 with those of Example 1, it can be seen that the DPPH free radical scavenging rates of the asparagus polysaccharides in Comparative Examples 1-8 are much lower than those in Example 1. The difference between Comparative Examples 1-8 and Example 1 lies in the different enzymatic hydrolysis sequences, enzyme types, electron beam irradiation parameters, and molecular weight cutoffs during the preparation of asparagus polysaccharides. This indicates that the enzymatic hydrolysis sequence, enzyme types, electron beam irradiation parameters, and molecular weight cutoffs all have a significant impact on the antioxidant effect of asparagus polysaccharides during preparation.

[0075] Table 3 Free radical scavenging results Group DPPH free radical scavenging rate (%) Example 1 91.6 Example 2 86.1 Example 3 88.3 Comparative Example 1 78.2 Comparative Example 2 71.8 Comparative Example 3 63.5 Comparative Example 4 67.3 Comparative Example 5 68.7 Comparative Example 6 75.4 Comparative Example 7 60.2 Comparative Example 8 72.5 Test Example 3 This test example uses asparagine polysaccharide 1 and asparagine active peptide prepared in Example 1, as well as the compositions of Examples 1-3 and Comparative Examples 1-9 as test samples. The skin barrier repair function of the compositions was evaluated by measuring their effects on the content of filaggrin (FLG) and lobelin (LOR) in epidermal keratinocytes (HACAT). The specific experimental methods are as follows: (1) Inoculation of epidermal keratinocytes: Add 2 mL of cell suspension to each well of the cell culture plate, with a cell suspension density of 2 × 10⁻⁶. 5 Inoculation was performed at a density of 1 / mL, and the cells were incubated overnight in an incubator (37°C, 5% CO2) (6-well plate).

[0076] (2) When the cell density reaches 40%-60%, the asparagine polysaccharide 1, asparagine active peptide, and the combination of Examples 1-3 and Comparative Examples 1-9 are diluted to a concentration of 5 mg / mL by cell culture medium. Then, 2 mL is administered to each well. At the same time, cell culture medium without the combination is used as a blank control group and cultured overnight.

[0077] (3) Sample processing: When the cell density reaches 70%-80%, discard the culture medium, wash with sterile PBS solution, discard the PBS after washing, add 0.5 mL of 0.25% trypsin-EDTA to each well for digestion, wash and resuspend the cells after digestion, sonicate the cells, centrifuge at 10000 rpm for 8 min, collect the supernatant, store it in a -80℃ freezer, and use it for kit testing.

[0078] (4) ELISA detection: Perform the detection according to the instructions of the FLG and LOR ELISA detection kit, and calculate the increase rate of FLG and LOR content: FLG content increase rate (%) = (FLG content in sample group - FLG content in blank control group) / FLG content in blank control group × 100%; LOR content increase rate (%) = (LOR content in sample group - LOR content in blank control group) / LOR content in blank control group × 100%.

[0079] The test results are shown in Table 4. The compositions of Examples 1-3 significantly increased the content of FLG and LOR in epidermal keratinocytes, indicating that the combination of asparagus polysaccharide and asparagus active peptide can significantly promote the secretion of FLG and LOR proteins by epidermal keratinocytes, thereby improving the skin barrier repair ability. Comparing the data of Example 1, Asparagus Polysaccharide 1, and Comparative Example 9, it can be seen that the combination of asparagus polysaccharide and asparagus active peptide within a specific dosage range can synergistically improve the ability of the composition to promote the secretion of FLG and LOR proteins by epidermal keratinocytes. Comparing the data of Example 1 and Comparative Examples 1-8, it can be seen that the preparation method of asparagus polysaccharide has a significant impact on the efficacy of asparagus polysaccharide in the composition, thereby affecting the composition's effect on promoting skin barrier repair.

[0080] Table 4 Results of the increase rate of FLG and LOR content Group FLG content increase rate (%) LOR content increase rate (%) Example 1 63.5 54.4 Example 2 58.7 50.8 Example 3 61.2 52.6 Comparative Example 1 47.6 45.1 Comparative Example 2 40.3 39.4 Comparative Example 3 32.9 30.5 Comparative Example 4 35.8 34.8 Comparative Example 5 39.4 36.7 Comparative Example 6 46.1 42.9 Comparative Example 7 33.6 34.0 Comparative Example 8 42.7 40.2 Comparative Example 9 49.5 46.7 Asparagine 1 34.1 30.6 Aspartic active peptides 29.3 26.4 Application examples This application example provides a repair serum that improves skin immunity and repairs the skin barrier. The repair serum is prepared using the compositions of Examples 1-3, resulting in serums 1-3 respectively.

[0081] The repair essence comprises the following components by weight percentage: 3% of the composition of Examples 1-3, 0.2% carbomer, 8% trehalose, 2% lecithin, 1% potassium sorbate, 0.2% arginine, and the balance being deionized water.

[0082] The preparation method of the repair essence specifically includes the following steps: S1. Mix trehalose, carbomer and 1 / 2 volume of deionized water, and homogenize at 80°C to obtain an aqueous solution; S2. When the temperature of the aqueous solution in S1 drops to 60℃, add potassium sorbate and stir evenly. When the system temperature drops to 40℃, add lecithin, each component in the composition and the remaining deionized water, and mix evenly. Finally, add arginine to adjust the pH to obtain the essence.

[0083] Meanwhile, a blank serum was prepared: compared with serums 1-3, the only difference was that no composition was added to the serum in the blank application example, and an equal amount of deionized water was used instead of the composition. The preparation method was the same as that of serums 1-3.

[0084] Test Example 4 Thirty volunteers will be recruited, 15 men and 15 women, aged 20-50, to conduct a skin irritation test using a closed patch test method. Patches no larger than 50 mm² will be selected. 2 A qualified patch tester with a depth of approximately 1 mm was used. The sample was placed in the small chamber of the patch tester, with a volume of 0.020 mL. The patch tester (Finn Chambers patch tester, 8 mm pore size, 10 chambers / each) containing the sample (Repair Essence 1-3 provided in the application example, blank essence, and distilled water as a blank control group) was applied to the flexor side of the subject's forearm using hypoallergenic adhesive tape. One patch tester was applied to each volunteer's arm. The patch tester was gently pressed with the palm of the hand to ensure even application to the skin, and left for 24 hours. Skin reactions were observed according to the standards shown in Table 5 at 30 min (after the indentation disappeared), 24 h, and 48 h after removing the patch tester, and the results were recorded.

[0085] Table 5 Skin Reaction Grading Standards Rating levels Skin reaction 0 negative reaction 1 Suspicious reaction, only slight erythema 2 Weak positive reaction (erythema reaction): erythema, infiltration, edema, and papules may be present. 3 Strong positive reaction (herpes reaction): erythema, infiltration, edema, papules; the reaction may extend beyond the test area. 4 Extremely strong positive reaction (confluent herpes simplex reaction): obvious erythema, severe infiltration, edema, confluent herpes simplex; reaction extends beyond the test area. After testing, the repair serums 1-3 and the blank serum in the application examples all showed negative reactions after human patch testing, indicating that they are safe and non-irritating to human skin.

[0086] Test Example 5 Using the repair serums 1-3 and the blank serum provided in the application examples as test samples, a skin barrier repair efficacy test was conducted. The test content is as follows: Forty volunteers with reddened skin and severely damaged skin barrier were recruited and randomly divided into four groups of 10 each. Each group was randomly assigned a test sample (1-3 units of the provided repair serum or a blank serum). Participants applied equal amounts of the sample to their entire face twice daily, morning and evening. Data were collected before use (T0) and after 28 days (T28). After arrival, participants sat quietly for 30 minutes in an air-conditioned room at 21±1℃ and 50±10% humidity. The transepidermal water loss (TEWL) value and facial a* value of the test product were measured using a transepidermal water loss probe and a skin color test probe. The improvement rate of facial TEWL value and the improvement rate of facial a* value were calculated to evaluate the repair efficacy of the test product. The calculation formula is as follows: TEWL value improvement rate (%) = [(TEWL value T0 - TEWL value T28) / TEWL value T0] × 100%; a* value improvement rate (%) = [(a* value T0 - a* value T28) / a* value T0] × 100%.

[0087] According to the TEWL value improvement rate and a* value improvement rate data shown in Table 6, compared with the blank essence, the TEWL value improvement rate and a* value improvement rate of the essence 1-3 provided by the present invention are significantly improved, indicating that the skin redness of the subjects is effectively relieved and the skin barrier is repaired. This further illustrates that the essence 1-3 provided by the present invention can regulate skin immune homeostasis, enhance skin defense and barrier repair capabilities.

[0088] Table 6 Results of TEWL value improvement rate and a* value improvement rate Group TEWL value improvement rate (%) a* value improvement rate (%) Serum 1 33.2 26.8 Serum 2 29.8 21.4 Serum 3 30.5 23.6 Blank Essence 1.7 0.5 Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A composition for improving skin immunity and skin barrier function, characterized in that, Including weight ratios of 1-4: 0.5g of asparagine polysaccharide and asparagine bioactive peptides; The asparagine polysaccharide is obtained by using asparagus as raw material and undergoing enzymatic hydrolysis and electron beam irradiation treatment, resulting in an asparagine polysaccharide with a molecular weight of <3KDa. The aspartic active peptides include short peptides with the following amino acid sequences: FF, FW, WFW, MPF, FFPF, FPF, WPF, WFL, LPF, FPL, LFP, FP, GFL, FLG, LGF, and APLF.

2. The composition according to claim 1, characterized in that, The preparation method of the asparagine polysaccharide includes the following steps: S1. Pulverize and sieve the dried asparagus to obtain asparagus powder. Add pure water to adjust the pH of the system to 6.0-7.

0. Add cellulase and α-galactosidase, stir to react, filter to obtain filter residue and first enzymatic hydrolysate. S2. Add pure water to the filter residue obtained in S1, adjust the pH of the system to 5.0-7.0, add papain, stir the reaction, filter, and obtain the second enzymatic hydrolysate; S3. Combine the first and second enzyme hydrolysates, inactivate the enzyme, concentrate, precipitate with ethanol, centrifuge to obtain the precipitate, dry, and pulverize into powder to obtain crude asparagus polysaccharide. S4. Dissolve crude asparagus polysaccharide in pure water, irradiate with an electron beam, separate the irradiated liquid by membrane separation, collect the permeate with a molecular weight cutoff of <3 kDa, freeze-dry, and obtain asparagus polysaccharide.

3. The composition according to claim 2, characterized in that, In step S1, the amount of cellulase added is 1%-3% of the mass of asparagus powder, and the amount of α-galactosidase added is 2%-4% of the mass of asparagus powder. The stirring reaction is carried out at 45-50℃ and 300-500 r / min for 60-100 min. In step S2, the amount of papain added is 1%-5% of the mass of asparagus powder. The stirring reaction is carried out at 55-60℃ and 300-500 r / min for 60-100 min.

4. The composition according to claim 2, characterized in that, The concentration in step S3 is vacuum concentration to 1 / 5-1 / 8 of the original volume; the ethanol precipitation is the addition of ethanol to the concentrate until the final ethanol concentration in the system reaches 80% v / v, followed by standing for 10-16 hours; the centrifugation is centrifugation at 8000-10000 r / min for 15-30 minutes.

5. The composition according to claim 2, characterized in that, In step S4, the electron beam irradiation temperature is 40-50℃, the irradiation dose is 60-80kGy, and the time is 10-30s.

6. The composition according to claim 1, characterized in that, The preparation method of the aspartic active peptide includes the following steps: (1) Crush the dried asparagus tuber to obtain asparagus powder, add pure water, stir and soak at 4-10℃ for 20-50 min, and treat with pulse ultrasound to obtain pretreated material; (2) Adjust the pH of the pretreated material to 7.2-8.5, add trypsin, carry out the first stirring reaction, filter with filter cloth to obtain filter residue and first peptide filtrate; take the filter residue, add pure water, adjust the pH to 6.2-7.5, add papain and neutral protease, carry out the second stirring reaction, filter with filter cloth to obtain second peptide filtrate; combine the two peptide filtrates, inactivate enzymes, filter by suction to obtain clear filtrate; (3) The clarified filtrate is concentrated, precipitated with ethanol, and centrifuged to obtain the supernatant. After removing the ethanol from the supernatant, the permeate with a molecular weight <5KDa is retained using an ultrafiltration membrane system and the permeate is collected. (4) The permeate is freeze-dried under vacuum to obtain aspartic active peptide.

7. The composition according to claim 6, characterized in that, The conditions for pulsed ultrasound treatment in step (1) are: power 300W, frequency 20~40kHz, pulse mode 3s working, 3s intermittent, and ultrasound treatment time 10-30min; the amount of trypsin added in step (2) is 1%-4% of the mass of asparagus powder, the temperature of the first stirring reaction is 45-55℃, the rotation speed is 300-500r / min, and the time is 60min, the amount of papain added is 1%-2% of the mass of asparagus powder, the amount of neutral protease added is 0.5%-1.5% of the mass of asparagus powder, the temperature of the second stirring reaction is 45-55℃, the rotation speed is 300-500r / min, and the time is 60min; the ethanol precipitation in step (3) is to slowly add 95% v / v ethanol to the concentrate while stirring at a rotation speed of 120-150r / min until the final concentration of ethanol in the system reaches 85% v / v, and then let it stand at 4℃ for 10-16h.

8. The use of the composition according to any one of claims 1-7 in the preparation of products that improve skin immunity and skin barrier function, characterized in that, The product in question is a cosmetic product.

9. A cosmetic product that improves skin immunity and skin barrier function, characterized in that, The composition comprising any one of claims 1-7.

10. The cosmetic product as described in claim 9, characterized in that, The composition accounts for 0.1%-5% of the total mass of the cosmetic.