Whitening composition containing pH-sensitive oxyresveratrol hydrogel and application

Abstract

The invention relates to a whitening composition containing pH-sensitive oxidized resveratrol hydrogel and application. The whitening composition is a composition of oxidized resveratrol hydrogel, a hydrolyzed opuntia pear flower extract and a mexican agastache rugosus flower / leaf / stem extract in a weight ratio of 1: (0.6-0.7): (0.01-0.02). The oxidized resveratrol hydrogel is prepared from the following raw materials in percentage by weight: 1 to 3 percent of oxidized resveratrol, 1 to 3 percent of 3-o-ethyl ascorbic acid, 15 to 20 percent of butanediol, 0.1 to 0.5 percent of sodium alginate, 0.1 to 0.5 percent of carboxymethylcellulose, 0.3 to 0.8 percent of calcium chloride and the balance of water. The three components of the whitening skincare product have a remarkable synergistic effect in the whitening aspect, the skin color can be jointly improved from different mechanisms, and meanwhile, the mildness and the safety are considered.

Description

Technical Field

[0001] The invention relates to the technical field of skin care products, and in particular to a whitening composition containing pH-sensitive oxidized resveratrol hydrogel and application thereof. Background Art

[0002] The skin is composed of the epidermis, dermis and subcutaneous tissue, and its pH value is distributed in a gradient. The outermost layer of the epidermis is the stratum corneum, which is weakly acidic and helps maintain the natural barrier function of the skin, while the basal layer at the junction of the dermis and epidermis is close to neutral, providing a suitable environment for cell proliferation and differentiation. From the life cycle of melanin in the skin mentioned above, it can be seen that melanin is first produced in the nearly neutral basal layer, and then ascends to the weakly acidic stratum corneum as the cells mature, and finally falls off with the metabolism of the skin. This process not only reveals the physiological mechanism of melanin production, but also shows that when applying topical skin care products, the skin care products will be affected by different pH environments during the process of penetrating into the skin, thereby affecting their efficacy.

[0003] As a stilbene compound, oxidized resveratrol has attracted much attention for its ability to inhibit tyrosinase activity and melanin production. According to studies, its ability to inhibit tyrosinase is even 32 times that of kojic acid. It is a highly potential tyrosinase inhibitor with significant whitening effects. However, although oxidized resveratrol has shown great potential in the field of whitening, its stability issues limit its effectiveness in practical applications. Oxidized resveratrol is extremely susceptible to ultraviolet and visible light, and it will rapidly isomerize under light conditions, resulting in degradation and discoloration, and its whitening effect will drop sharply.

[0004] Many whitening products on the market contain traditional whitening ingredients such as vitamin C derivatives and arbutin, but these ingredients often face problems such as insufficient stability and easy oxidation and inactivation. In addition, some products may add excessive chemical ingredients in pursuit of instant whitening effects, which may not only irritate the skin, but also cause adverse reactions such as allergies. Therefore, how to improve the stability and safety of products while ensuring whitening effects has become an important topic in the current research and development of whitening products. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a whitening composition containing a pH-sensitive oxidized resveratrol hydrogel, a preparation method and an application thereof. The oxidized resveratrol is first encapsulated in the form of a hydrogel to improve its stability; the components of the whitening composition are rationally compounded to achieve a dual whitening effect of inhibiting melanin production in the basal layer of the skin and promoting melanin metabolism in the stratum corneum.

[0006] To achieve the above object, the technical solution adopted by the present invention is:

[0007] In a first aspect, the present invention provides a whitening composition containing a pH-sensitive oxidized resveratrol hydrogel, comprising the following components: oxidized resveratrol hydrogel, hydrolyzed prickly pear cactus flower extract and Mexican patchouli flower / leaf / stem extract; wherein the weight ratio of the oxidized resveratrol hydrogel, the hydrolyzed prickly pear cactus flower extract and the Mexican patchouli flower / leaf / stem extract is 1:(0.6-0.7):(0.01-0.02); the oxidized resveratrol hydrogel comprises the following raw materials in weight percentage: 1-3% oxidized resveratrol, 1-3% 3-o-ethyl ascorbic acid, 15-20% butanediol, 0.1-0.5% sodium alginate, 0.1-0.5% carboxymethyl cellulose and 0.3-0.8% calcium chloride, and the balance is water.

[0008] In the oxidized resveratrol hydrogel, sodium alginate and carboxymethyl cellulose are used as pH-sensitive materials because both contain a large number of carboxyl groups. Under acidic conditions, the carboxyl groups will not ionize, and the negative charge in the hydrogel network is less, and the electrostatic repulsion is weak, so the hydrogel structure is relatively tight and the contents are not easily released; in a near-neutral or weakly alkaline environment, the carboxyl groups will ionize into carboxyl groups, resulting in an increase in the negative charge in the hydrogel network, thereby generating electrostatic repulsion, causing the hydrogel network structure to expand, the gaps to increase, and the whitening ingredients to be released. Therefore, sodium alginate and carboxymethyl cellulose are used as pH-sensitive materials. They can respond to the pH changes in different layers of the skin and intelligently release oxidized resveratrol and 3-o-ethyl ascorbic acid. At the same time, butanediol provides a moisturizing effect, and calcium chloride helps to form a stable hydrogel network.

[0009] The present invention utilizes the above characteristics of pH-sensitive materials to encapsulate the easily inactivated oxidized resveratrol into a hydrogel, which can reduce the degradation effect of ultraviolet and visible light on it on the one hand, and avoid the influence of the acidity of the stratum corneum when the skin care product penetrates into the skin on the other hand, and only releases the contents to exert the whitening effect when the basal layer reaches a nearly neutral environment.

[0010] In addition, the present invention also rationally compounds the hydrogel with other skin care ingredients. The oxidized resveratrol hydrogel can inhibit the production of melanin in the basal layer of the skin; the hydrolyzed prickly pear cactus flower extract can enhance the activity of enzymes related to skin keratin exfoliation, thereby gently promoting keratin exfoliation, promoting the metabolism of melanin, and reducing the deposition of melanin in the epidermis, thereby improving the problems of uneven skin color and dullness; the Mexican patchouli flower / leaf / stem extract has a certain soothing effect, reduces post-inflammatory pigmentation, thereby indirectly improving skin color, and the composition can be used in skin care products for people with sensitive skin.

[0011] Preferably, the mass ratio of oxidized resveratrol to 3-o-ethyl ascorbic acid in the oxidized resveratrol hydrogel is 1:1.

[0012] Preferably, the manufacturer of the oxidized resveratrol is Naturalis Srl, and the product name is oxyresveratrol.

[0013] Preferably, the manufacturer of the hydrolyzed Opuntia cactus flower extract is Synsil of the United States, and the product name is: Cactus enzyme.

[0014] Preferably, the manufacturer of the Agastache rugosa flower / leaf / stem extract is Provital, and the product name is AGASCALM TM .

[0015] Specifically, the method for preparing the oxidized resveratrol hydrogel comprises the following steps:

[0016] (1) dissolving resveratrol oxide in butanediol to obtain a first solution; then dissolving 3-o-ethyl ascorbic acid, sodium alginate, and carboxymethyl cellulose in part of water, and mixing the mixture to obtain a second solution;

[0017] (3) mixing the first solution and the second solution to obtain an inner phase liquid; dissolving calcium chloride in the remaining water to obtain a receiving solution;

[0018] (4) using a droplet microfluidic chip to mix the internal phase liquid and the receiving liquid and form droplets containing microspheres through shearing, collecting the generated droplets, filtering, and adding water to the original amount to obtain the oxidized resveratrol hydrogel.

[0019] Preferably, in the step (4) of oxidizing the resveratrol hydrogel, the flow rate of the inner phase liquid is 0.1-0.3 mL / h, the flow rate of the receiving liquid is 0.2-0.4 mL / h, and the particle size of the microspheres is 100-260 nm.

[0020] In a second aspect, the present invention provides use of the whitening composition containing the pH-sensitive oxidized resveratrol hydrogel in the first aspect in the preparation of skin care products.

[0021] Preferably, the skin care product is at least one of lotion, emulsion, cream, mask, essence or spray, and the amount of the skin care composition added is 0.5-5% of the total weight of the skin care product. Since oxidized resveratrol has poor water solubility, it can be used in water-based or oil-in-water products after being encapsulated in the form of hydrogel.

[0022] In a third aspect, the present invention provides a whitening lotion comprising the following raw materials in weight percentage: 4%-6% of the whitening composition containing pH-sensitive oxidized resveratrol hydrogel in the first aspect, 0.25-0.35% of a thickener, 2-4% of an emollient, 0.5-2% of an emulsifier, 0.5-1.2% of a preservative, 0.5-2% of a stabilizer and 0.4-1% of an antioxidant, and the balance being deionized water.

[0023] Preferably, the thickener is xanthan gum and / or carbomer.

[0024] Preferably, the emollient is caprylic / capric triglyceride.

[0025] Preferably, the emulsifier is C14-22 alcohol / C12-20 alkyl glucoside.

[0026] Preferably, the stabilizer is arginine.

[0027] Preferably, the antioxidant is tocopherol acetate.

[0028] Preferably, the preservative is p-hydroxyacetophenone and / or hexylene glycol.

[0029] In a fourth aspect, the present invention provides a method for preparing the whitening lotion in the third aspect, comprising the following steps:

[0030] The emollient, emulsifier and antioxidant are mixed and heated to 75-85° C. to obtain the oil phase; the thickener, stabilizer and water are mixed and heated to 75-85° C. to obtain the water phase; the oil phase is added to the water phase and homogenized to obtain an emulsion; the whitening composition containing the pH-sensitive oxidized resveratrol hydrogel and the preservative are added after cooling to below 45° C. to obtain the whitening emulsion.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] (1) The oxidized resveratrol hydrogel in the whitening composition of the present invention inhibits melanin production from the basal layer, the hydrolyzed prickly pear cactus flower extract reduces melanin deposition by promoting keratin metabolism, and the Mexican patchouli flower / leaf / stem extract soothes the skin to make it suitable for people with sensitive skin. The three work synergistically to improve skin color from different mechanisms. This combination not only reduces melanin production, but also improves uneven skin color and dullness in multiple dimensions by promoting keratin metabolism and soothing the skin. Therefore, the three components of the whitening skin care product of the present invention have a significant synergistic effect in whitening, can improve skin color from different mechanisms, and take into account mildness and safety.

[0033] (2) In order to avoid the inactivation of oxidized resveratrol, the present invention encapsulates oxidized resveratrol in the form of a hydrogel. In the hydrogel of oxidized resveratrol, sodium alginate and carboxymethyl cellulose are pH-sensitive materials. The two materials respond to the pH changes of each layer of the skin and intelligently release the whitening components of oxidized resveratrol and 3-o-ethyl ascorbic acid. Butanediol moisturizes and calcium chloride helps stabilize the gel. The present invention uses pH-sensitive materials to encapsulate oxidized resveratrol, weaken photodegradation, avoid the acidic influence of the stratum corneum, and release it in the nearly neutral environment of the basal layer to exert a whitening effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a particle size distribution diagram of the hydrogel prepared using the method described in Example 1;

[0035] Figure 2 This is a particle size distribution diagram of the hydrogel prepared using the method described in Example 2;

[0036] Figure 3 The particle size distribution diagram of the hydrogel prepared using the method described in Example 3. DETAILED DESCRIPTION

[0037] In order to better illustrate the purpose, technical solutions and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments.

[0038] The sources of materials used in the following examples and comparative examples are as follows:

[0039] Oxylated resveratrol: The manufacturer is Naturalis Srl and the product name is oxyresveratrol.

[0040] Hydrolyzed Opuntia cactus flower extract: The manufacturer is Synsil, USA. The product name is: Cactus enzyme.

[0041] Agastache rugosa flower / leaf / stem extract: manufacturer is Provital, product name is: AGASCALM TM .

[0042] 3-o-Ethyl ascorbic acid: The manufacturer is Shanghai Jiakai Biotechnology Co., Ltd., and the product name is: GwhiteVCE.

[0043] Unless otherwise specified, other materials, reagents, etc. used in the examples and comparative examples can be obtained from commercial sources.

[0044] Example 1

[0045] A whitening composition containing pH-sensitive oxidized resveratrol hydrogel, comprising the following components: oxidized resveratrol hydrogel, hydrolyzed opuntia cactus flower extract and patchouli flower / leaf / stem extract; wherein the weight ratio of the oxidized resveratrol hydrogel, the hydrolyzed opuntia cactus flower extract and patchouli flower / leaf / stem extract is 1:0.67:0.01; and the total weight of the oxidized resveratrol hydrogel, the hydrolyzed opuntia cactus flower extract and patchouli flower / leaf / stem extract is 50 parts.

[0046] The oxidized resveratrol hydrogel comprises the following raw materials in percentage by weight: 2% oxidized resveratrol, 2% 3-o-ethyl ascorbic acid, 18% butanediol, 0.3% sodium alginate, 0.3% carboxymethyl cellulose and 0.5% calcium chloride, and the balance is water.

[0047] Specifically, the method for preparing the oxidized resveratrol hydrogel comprises the following steps:

[0048] (1) dissolving resveratrol oxide in butanediol to obtain a first solution; then dissolving 3-o-ethyl ascorbic acid, sodium alginate, and carboxymethyl cellulose in part of water, and mixing the mixture to obtain a second solution;

[0049] (3) mixing the first solution and the second solution to obtain an inner phase liquid; dissolving calcium chloride in the remaining water to obtain a receiving solution;

[0050] (4) Using a droplet microfluidic chip to mix the internal phase liquid and the receiving liquid and form droplets containing microspheres through shearing, collecting the generated droplets, filtering, and adding water to the original amount to obtain the oxidized resveratrol hydrogel. The flow rate of the internal phase liquid is 0.2 mL / h, the flow rate of the receiving liquid is 0.4 mL / h, and the particle size of the microspheres is 100-200 nm.

[0051] Example 2

[0052] A whitening composition containing pH-sensitive oxidized resveratrol hydrogel, comprising the following components: oxidized resveratrol hydrogel, hydrolyzed opuntia cactus flower extract and patchouli flower / leaf / stem extract; wherein the weight ratio of the oxidized resveratrol hydrogel, the hydrolyzed opuntia cactus flower extract and patchouli flower / leaf / stem extract is 1:0.6:0.01; and the total weight of the oxidized resveratrol hydrogel, the hydrolyzed opuntia cactus flower extract and patchouli flower / leaf / stem extract is 50 parts.

[0053] The oxidized resveratrol hydrogel comprises the following raw materials in percentage by weight: 1% oxidized resveratrol, 3% 3-o-ethyl ascorbic acid, 15% butanediol, 0.1% sodium alginate, 0.1% carboxymethyl cellulose and 0.3% calcium chloride, and the balance is water.

[0054] Specifically, the method for preparing the oxidized resveratrol hydrogel comprises the following steps:

[0055] (1) dissolving resveratrol oxide in butanediol to obtain a first solution; then dissolving 3-o-ethyl ascorbic acid, sodium alginate, and carboxymethyl cellulose in part of water, and mixing the mixture to obtain a second solution;

[0056] (3) mixing the first solution and the second solution to obtain an inner phase liquid; dissolving calcium chloride in the remaining water to obtain a receiving solution;

[0057] (4) Using a droplet microfluidic chip to mix the internal phase liquid and the receiving liquid and form droplets containing microspheres through shearing, collecting the generated droplets, filtering, and adding water to the original amount to obtain the oxidized resveratrol hydrogel. The flow rate of the internal phase liquid is 0.1 mL / h, and the flow rate of the receiving liquid is 0.3 mL / h, and the particle size of the microspheres is 150-260 nm.

[0058] Example 3

[0059] A whitening composition containing pH-sensitive oxidized resveratrol hydrogel, comprising the following components: oxidized resveratrol hydrogel, hydrolyzed opuntia cactus flower extract and patchouli flower / leaf / stem extract; wherein the weight ratio of the oxidized resveratrol hydrogel, the hydrolyzed opuntia cactus flower extract and patchouli flower / leaf / stem extract is 1:0.7:0.02; and the total weight of the oxidized resveratrol hydrogel, the hydrolyzed opuntia cactus flower extract and patchouli flower / leaf / stem extract is 50 parts.

[0060] The oxidized resveratrol hydrogel comprises the following raw materials in percentage by weight: 3% oxidized resveratrol, 1% 3-o-ethyl ascorbic acid, 20% butanediol, 0.5% sodium alginate, 0.5% carboxymethyl cellulose and 0.8% calcium chloride, and the balance is water.

[0061] Specifically, the method for preparing the oxidized resveratrol hydrogel comprises the following steps:

[0062] (1) dissolving resveratrol oxide in butanediol to obtain a first solution; then dissolving 3-o-ethyl ascorbic acid, sodium alginate, and carboxymethyl cellulose in part of water, and mixing the mixture to obtain a second solution;

[0063] (3) mixing the first solution and the second solution to obtain an inner phase liquid; dissolving calcium chloride in the remaining water to obtain a receiving solution;

[0064] (4) Using a droplet microfluidic chip to mix the internal phase liquid and the receiving liquid and form droplets containing microspheres through shearing, collecting the generated droplets, filtering, and adding water to the original amount to obtain the oxidized resveratrol hydrogel. The flow rate of the internal phase liquid is 0.1 mL / h, the flow rate of the receiving liquid is 0.4 mL / h, and the particle size of the microspheres is 110-220 nm.

[0065] Comparative Example 1

[0066] The difference between Comparative Example 1 and Example 1 is that the total mass of the whitening composition remains unchanged, no oxidized resveratrol hydrogel is added, and the missing amount is made up by using hydrolyzed prickly pear cactus flower extract and Mexican patchouli flower / leaf / stem extract in a weight ratio of 0.67:0.01.

[0067] Comparative Example 2

[0068] The difference between Comparative Example 2 and Example 1 is that the total mass of the whitening composition remains unchanged, no hydrolyzed Opuntia ficus-indica flower extract is added, and the missing amount is made up by using oxidized resveratrol hydrogel and Agastache rugosa flower / leaf / stem extract in a weight ratio of 1:0.01.

[0069] Comparative Example 3

[0070] The difference between Comparative Example 3 and Example 1 is that the total mass of the whitening composition remains unchanged, no Agastache rugosa flower / leaf / stem extract is added, and the missing amount is made up by using oxidized resveratrol hydrogel and hydrolyzed opuntia cactus flower extract in a weight ratio of 1:0.67.

[0071] Comparative Example 4

[0072] The difference between Comparative Example 4 and Example 1 is that the total weight of the whitening composition remains unchanged, and the weight ratio of oxidized resveratrol hydrogel, hydrolyzed opuntia cactus flower extract and Patchouli oleraceus flower / leaf / stem extract is 1:0.01:0.67.

[0073] Comparative Example 5

[0074] The difference between Comparative Example 5 and Example 1 is that the total weight of the whitening composition remains unchanged, and the weight ratio of oxidized resveratrol hydrogel, hydrolyzed opuntia cactus flower extract and Patchouli oleraceus flower / leaf / stem extract is 0.01:0.67:1.

[0075] Comparative Example 6

[0076] The difference between Comparative Example 6 and Example 1 is that the total weight of the whitening composition remains unchanged, and the weight ratio of oxidized resveratrol hydrogel, hydrolyzed opuntia cactus flower extract and Patchouli oleraceus flower / leaf / stem extract is 0.67:1:0.01.

[0077] Comparative Example 7

[0078] The difference between Comparative Example 7 and Example 1 is that: no oxidized resveratrol hydrogel is added, and an equal amount of oxidized resveratrol and 3-o-ethyl ascorbic acid are used instead.

[0079] Comparative Example 8

[0080] The difference between Comparative Example 8 and Example 1 is that 3-o-ethyl ascorbic acid is not added to the oxidized resveratrol hydrogel, and an equal amount of oxidized resveratrol is used instead.

[0081] Comparative Example 9

[0082] The difference between Comparative Example 9 and Example 1 is that the oxidized resveratrol in the oxidized resveratrol hydrogel is replaced by an equal amount of 3-o-ethyl ascorbic acid.

[0083] The preparation method of the whitening composition of Examples 1-3 and Comparative Examples 1-9 is as follows: the formulated resveratrol hydrogel, the hydrolyzed opuntia cactus flower extract and the mexican patchouli flower / leaf / stem extract are mixed at room temperature and stirred to obtain the whitening composition.

[0084] Test Example 1

[0085] 1. Encapsulation rate

[0086] Test sample: hydrogel prepared by the method described in Example 1;

[0087] Test method: Calculate based on oxidized resveratrol. Collect the filtrate obtained in the filtration step (4) of the oxidized resveratrol hydrogel preparation process of Example 1, and filter until the hydrogel no longer drips water. The oxidized resveratrol content in the test filtrate is a, and the total amount of oxidized resveratrol used is b. According to the formula: encapsulation rate = (ba) / b×100%, the encapsulation rate is obtained;

[0088] The content of oxidized resveratrol was determined by HPLC. The test method was as follows: prepare standard working solution: use methanol to prepare oxidized resveratrol standard into solutions with concentrations of 0.1μg / mL, 0.5μg / mL, 1μg / mL, 2μg / mL, 5μg / mL, and 10μg / mL; sample test method: weigh about 0.1g (accurate to 0.0001g) of sample in a 10ml colorimetric tube, dissolve with 5ml methanol, ultrasonically bath for 15min, vortex mix for 1min, dilute to scale with methanol, take 1ml of supernatant and filter through a 0.2μm filter membrane for standby use. The filtrate can be directly filtered using a 0.2μm filter membrane. The test conditions are: chromatographic column C18-150mm×3mm×2.7μm, column temperature 35℃, flow rate 0.8ml / min, DAD detector, detection wavelength 328nm, injection volume 5μL, and mobile phase as shown in Table 1.

[0089] Table 1 Mobile phase data

[0090]

[0091]

[0092] According to the following formula: Calculate, where X is the content of the component to be tested, %; C is the concentration of the component to be tested solution obtained according to the standard curve, μg / mL; V is the volume of the solution, mL; f is the dilution factor; m is the sample weight, g.

[0093] Test results: The encapsulation efficiency of the oxidized resveratrol hydrogel prepared in Example 1 was calculated to be 85.27%.

[0094] 2. Particle size test

[0095] Test sample: hydrogel prepared by the method described in Examples 1-3;

[0096] Test method: Place three groups of hydrogel samples under a microscope and take photos. The pictures must contain at least 100 particles. Use ImageJ software for analysis and calculate the average diameter, which is the hydrogel particle size.

[0097] Test results: Figure 1 As shown, the particle size of the hydrogel prepared by the method shown in Example 1 is between 100-200 nm, and the particle size range with the highest probability of appearing is 150-160 nm.

[0098] like Figure 2 As shown, the particle size of the hydrogel prepared by the method shown in Example 2 is between 110-260 nm, wherein the particle size range with the highest probability of appearing is 200-210 nm.

[0099] like Figure 3 As shown, the particle size of the hydrogel prepared by the method shown in Example 1 is between 110-220 nm, and the particle size range with the highest probability of appearing is 160-170 nm.

[0100] 3. Tyrosinase inhibition test

[0101] Test method: Set up positive control: dilute with PBS buffer to: 1mg / mL, 0.2mg / mL, 0.04mg / mL, 0.008mg / mL series concentration gradient to verify the test system;

[0102] Test sample treatment: Take equal amounts of the whitening compositions prepared in Examples 1-3 and Comparative Examples 1-9 as test samples, and dilute them appropriately with PBS solution;

[0103] Prepare A, B, C, and D test tubes for each test sample and prepare a blank control tube according to the following requirements. After preparation, add 0.5 mL of L-DOPA solution (wherein the mass percentage of L-DOPA is 5%) to each tube. Keep the test tubes and the blank control tube in a constant temperature of 37°C for 30 minutes, and measure their absorbance values ​​at 475 nm respectively. Repeat the experiment for each sample 3 times;

[0104] The requirements for the solutions in the A, B, C, and D test tubes are as follows: Tube A: 3 mL PBS buffer and 0.5 mL tyrosinase; Tube B: 3.5 mL PBS buffer; Tube C: 1 mL sample solution, 2 mL PBS buffer and 0.5 mL tyrosinase; Tube D: 1 mL sample solution and 2.5 mL PBS buffer;

[0105] Zero adjustment: PBS solution;

[0106] The tyrosinase inhibition rate of each group of samples was calculated according to the formula. The calculation formula of tyrosinase inhibition rate is:

[0107] Tyrosinase inhibition rate = 1-(CD) / (AB)×100%; wherein A is the absorbance value of tube A, B is the absorbance value of tube B, C is the absorbance value of tube C, and D is the absorbance value of tube D. See Table 1 for data.

[0108] Table 2 Tyrosinase inhibition rate of each group of samples

[0109] Group / Performance Tyrosinase inhibition rate / % Example 1 86.23 Example 2 80.22 Example 3 82.76 Comparative Example 1 40.19 Comparative Example 2 50.23 Comparative Example 3 47.56 Comparative Example 4 66.35 Comparative Example 5 64.22 Comparative Example 6 65.56 Comparative Example 7 60.23 Comparative Example 8 56.12 Comparative Example 9 52.33

[0110] It can be seen from Table 2 that, combined with the data of Example 1 and Comparative Examples 1-3, when the oxidized resveratrol hydrogel, the hydrolyzed opuntia cactus flower extract and the Patchouli oleraceus flower / leaf / stem extract are used in combination, the whitening performance is better. When any one of the oxidized resveratrol hydrogel, the hydrolyzed opuntia cactus flower extract and the Patchouli oleraceus flower / leaf / stem extract is missing, the whitening performance of the composition decreases.

[0111] Combining the data of Examples 1-3 and Comparative Examples 4-6, it can be seen that when the weight ratio of oxidized resveratrol hydrogel, hydrolyzed opuntia cactus flower extract and Patchouli oleraceus flower / leaf / stem extract is 1:(0.6-0.7):(0.01-0.02), the whitening performance of the composition reaches a better level.

[0112] Combining the data of Example 1 and Comparative Example 7, it can be seen that when oxidized resveratrol and 3-o-ethyl ascorbic acid are encapsulated in the form of a hydrogel, the tyrosinase inhibitory ability of the composition is improved.

[0113] Combining the data of Example 1 and Comparative Examples 8-9, it can be seen that when oxidized resveratrol and 3-o-ethyl ascorbic acid are used in combination, the whitening performance is better.

[0114] Application Example 1 and Comparative Application Examples 1-9

[0115] The whitening compositions of Example 1 and Comparative Examples 1-9 were added to the emulsion at a concentration of 5 wt %, respectively, to obtain the whitening emulsions of Application Example 1 and Comparative Application Examples 1-9. The formulas are shown in Table 3.

[0116] Table 3 Formulations of whitening lotions of Application Example 1 and Comparative Application Examples 1-9

[0117]

[0118] The preparation method of the whitening emulsion of Application Example 1 and Comparative Application Examples 1-9 comprises the following steps:

[0119] The emollient, emulsifier and antioxidant are mixed and heated to 80°C to obtain the oil phase; the thickener, stabilizer and water are mixed and heated to 80°C to obtain the water phase; the oil phase is added to the water phase and homogenized to obtain an emulsion; after cooling to 45°C, the whitening composition containing the pH-sensitive oxidized resveratrol hydrogel and the preservative are added to obtain the whitening emulsion.

[0120] Comparative Application Example 10

[0121] The emulsion of comparative application example 10 does not contain the whitening composition, but uses an equal amount of deionized water instead of the whitening composition. The preparation method is the same as that of application example 1.

[0122] Test Example 2

[0123] 1. Patch test

[0124] Test sample: Emulsion of Application Example 1

[0125] Test method: 10 subjects were selected, about 0.020g of the test substance was placed in a patch tester and applied to the flexor side of the subject's forearm. The test substance was removed after 24 hours, and the skin reaction was observed at 0.5, 24, and 48 hours after removal, and the results were recorded according to the skin reaction grading standards in the currently valid technical specifications.

[0126] Test results: The results of the human skin patch test showed that no adverse skin reactions were found in 10 people.

[0127] 2. Whitening effect test

[0128] Test samples: emulsions of application example 1 and comparative application examples 1-10

[0129] Test method: 60 subjects aged 18-45 years old with ITA° values ​​between 20-41 were screened and randomly divided into 12 groups, 5 people in each group. They used the lotions of Application Example 1 and Comparative Application Examples 1-10 for 28 consecutive days, once in the morning and evening, with a dosage of 1 mL each time. The subjects were required to undergo ITA° value tests before the test, after 14 days of use, and after 28 days of use. The specific steps were as follows: clean the face with a cleanser and dry it with a crumb-free absorbent tissue, then sit still for at least 30 minutes until the skin condition stabilizes, and use a color probe Colorimeter CL400 to measure the ITA° value. Analyze the improvement of each subject on days 14 and 28. The improvement is represented by the ITA° value improvement rate, which is calculated as follows: Improvement rate relative to ITA° value = |(X 使用后 -X 使用前 ) / X 使用前 ×100%|, the test results are shown in Table 4.

[0130] Table 4 Whitening and freckle removal test results of the skin care products of the embodiments and comparative examples

[0131]

[0132] As shown in Table 4, the whitening lotion prepared by using the whitening composition containing pH-sensitive oxidized resveratrol hydrogel of Example 1 has a significantly better whitening effect than Comparative Examples 1-3 containing only oxidized resveratrol hydrogel, hydrolyzed prickly pear cactus flower extract and Mexican Patchouli flower / leaf / stem extract, Comparative Examples 4-6 of whitening compositions with a specific mass ratio, Comparative Example 7 in which oxidized resveratrol and 3-o-ethyl ascorbic acid are directly added, and Comparative Examples 8-9 in which only oxidized resveratrol and 3-o-ethyl ascorbic acid are contained in the hydrogel. This is consistent with the result of Test Example 1. This also shows that the three components of the oxidized resveratrol hydrogel, hydrolyzed prickly pear cactus flower extract and Mexican Patchouli flower / leaf / stem extract of the present invention have a synergistic effect, and the emulsion added with this composition can improve the skin color from different mechanisms and achieve a whitening effect, while taking into account both mildness and safety.

[0133] It is worth noting that the whitening gap between the emulsions of Application Example 1 and Comparative Application Example 7 is significantly greater than the whitening gap between the compositions of Example 1 and Comparative Example 7 in Test Example 1. This is because sodium alginate and carboxymethyl cellulose are pH-sensitive materials in the hydrogel of oxidized resveratrol. The two materials respond to pH changes in each layer of the skin and intelligently release the whitening components of oxidized resveratrol and 3-o-ethyl ascorbic acid. Butanediol moisturizes and calcium chloride helps stabilize the gel. Therefore, the present invention uses pH-sensitive materials to encapsulate oxidized resveratrol, reduce photodegradation, avoid the acidic influence of the stratum corneum, and release it in a nearly neutral environment in the basal layer to exert a whitening effect.

[0134] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A whitening composition containing pH-sensitive oxidized resveratrol hydrogel, characterized in that: The invention comprises the following components: oxidized resveratrol hydrogel, hydrolyzed prickly pear cactus flower extract and Mexican patchouli flower / leaf / stem extract; wherein the weight ratio of the oxidized resveratrol hydrogel, the hydrolyzed prickly pear cactus flower extract and the Mexican patchouli flower / leaf / stem extract is 1:(0.6-0.7):(0.01-0.02); the oxidized resveratrol hydrogel comprises the following raw materials in weight percentage: 1-3% oxidized resveratrol, 1-3% 3-o-ethyl ascorbic acid, 15-20% butanediol, 0.1-0.5% sodium alginate, 0.1-0.5% carboxymethyl cellulose and 0.3-0.8% calcium chloride, and the balance is water.

2. The whitening composition containing pH-sensitive oxidized resveratrol hydrogel according to claim 1, characterized in that: The mass ratio of oxidized resveratrol to 3-o-ethyl ascorbic acid in the oxidized resveratrol hydrogel is 1:

1.

3. The whitening composition containing pH-sensitive oxidized resveratrol hydrogel according to claim 1, characterized in that: The components of the whitening composition are selected from at least one of the following (I)-(III): (I) The manufacturer of the oxidized resveratrol is Naturalis Srl, and the product name is oxyresveratrol; (II) The manufacturer of the hydrolyzed Opuntia cactus flower extract is Synsil of the United States, and the product name is: EEO Cactus Enzyme; (III) The manufacturer of the Agastache rugosa flower / leaf / stem extract is Provital, and the product name is AGASCALM TM。 4. The whitening composition containing pH-sensitive oxidized resveratrol hydrogel according to claim 1, characterized in that: The method for preparing the oxidized resveratrol hydrogel comprises the following steps: (1) dissolving resveratrol oxide in butanediol to obtain a first solution; then dissolving 3-o-ethyl ascorbic acid, sodium alginate, and carboxymethyl cellulose in part of water, and mixing the mixture to obtain a second solution; (3) mixing the first solution and the second solution to obtain an inner phase liquid; dissolving calcium chloride in the remaining water to obtain a receiving solution; (4) using a droplet microfluidic chip to mix the internal phase liquid and the receiving liquid and form droplets containing microspheres through shearing, collecting the generated droplets, filtering, and adding water to the original amount to obtain the oxidized resveratrol hydrogel.

5. The whitening composition containing pH-sensitive oxidized resveratrol hydrogel according to claim 4, characterized in that: In the step (4) of oxidizing the resveratrol hydrogel, the flow rate of the inner phase liquid is 0.1-0.3 mL / h, the flow rate of the receiving liquid is 0.2-0.4 mL / h, and the particle size of the microspheres is 100-260 nm.

6. Use of the whitening composition containing pH-sensitive oxidized resveratrol hydrogel according to any one of claims 1 to 5 in the preparation of skin care products.

7. Use of a whitening composition containing pH-sensitive oxidized resveratrol hydrogel according to claim 6 in the preparation of skin care products, characterized in that: The skin care product is at least one of lotion, emulsion, cream, mask, essence or spray, and the added amount of the skin care composition is 0.5-5% of the total weight of the skin care product.

8. A whitening lotion, characterized in that: The invention comprises the following raw materials in weight percentage: 4%-6% of the whitening composition containing pH-sensitive oxidized resveratrol hydrogel according to any one of claims 1 to 5, 0.25-0.35% of a thickener, 2-4% of an emollient, 0.5-2% of an emulsifier, 0.5-1.2% of a preservative, 0.5-2% of a stabilizer and 0.4-1% of an antioxidant, and the balance is deionized water.

9. The whitening emulsion according to claim 8, characterized in that The raw material is selected from at least one of (a) to (f): (a) the thickener is xanthan gum and / or carbomer; (b) the emollient is caprylic / capric triglyceride; (c) the emulsifier is C14-22 alcohol / C12-20 alkyl glucoside; (d) the stabilizer is arginine; (e) the antioxidant is tocopherol acetate; (f) The preservative is p-hydroxyacetophenone and / or hexylene glycol.

10. The method for preparing the whitening emulsion according to claim 8, characterized in that: The following steps are involved: The emollient, emulsifier and antioxidant are mixed and heated to 75-85° C. to obtain the oil phase; the thickener, stabilizer and water are mixed and heated to 75-85° C. to obtain the water phase; the oil phase is added to the water phase and homogenized to obtain an emulsion; the whitening composition containing the pH-sensitive oxidized resveratrol hydrogel and the preservative are added after cooling to below 45° C. to obtain the whitening emulsion.

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