A highly effective and stable whitening composition containing glabridin and pterostilbene and its application

Abstract

The present invention belongs to the field of cosmetic technology, and more particularly to a highly efficient and stable whitening composition and application containing glabridin and pterostilbene. The whitening composition includes the following components in parts by weight: 0.01-0.1 parts of glabridin, 0.01-0.1 parts of pterostilbene, 0.05-0.2 parts of stearyl glycyrrhetinate and 0.05-0.2 parts of tetrahydromethylpyrimidine carboxylic acid. The present invention prepares a stable and efficient synergistic whitening composition by scientifically matching the above four components, and the four components cooperate with each other to synergistically enhance the antioxidant free radical scavenging ability of the composition and the inhibitory effect of tyrosinase activity, thereby achieving a good whitening effect, and the whitening composition has safety, stability and mildness, ensuring a wide range of applicable populations, and bringing a more comprehensive and effective skin care experience to users.

Description

Technical Field

[0001] The invention belongs to the technical field of cosmetics, and in particular relates to a highly effective and stable whitening composition containing glabridin and pterostilbene and an application thereof. Background Art

[0002] With the continuous development and progress of society, people's quality of life has gradually improved, and skin care products have increasingly entered thousands of households. Among them, the demand for skin care products with whitening function has become increasingly prominent.

[0003] Melanin is the culprit that affects whitening. It is synthesized in melanocytes, and the production process requires several basic substances: tyrosine, tyrosinase, oxygen, and DOPA. Tyrosine is the main raw material for melanin production, and tyrosinase plays a key role in promoting the conversion of tyrosine into melanin, while oxygen is essential in the oxidation process of DOPA. The production of melanin in the skin involves a series of complex physiological and biochemical processes, including the migration, division and maturation of melanocytes, the transport of melanin particles, and the final excretion of melanin, which forms the skin problems we see, such as spots and uneven skin color.

[0004] As the whitening cosmetics market continues to grow, consumers are increasingly demanding safe and effective whitening products. However, a single ingredient often fails to achieve the desired whitening effect, and may be insufficient in stability and safety. Therefore, it is particularly important to develop a composite whitening technology that can synergistically enhance the effect. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide a highly efficient and stable whitening composition containing glycyrrhizin and pterostilbene and its application, so as to achieve efficient inhibition of tyrosinase and protect melanocytes from oxidative stress, thereby achieving a rapid and lasting whitening effect, while ensuring the mildness and stability of the product.

[0006] To achieve the above objectives, the technical solutions adopted by the present invention include:

[0007] In a first aspect, the present invention provides a whitening composition, comprising the following components in parts by weight: 0.01-0.1 parts of glabridin, 0.01-0.1 parts of pterostilbene, 0.05-0.2 parts of stearyl glycyrrhetinate and 0.05-0.2 parts of ectoine.

[0008] Glabridin is a flavonoid extracted from licorice plants. It has not been widely used for a long time due to its high cost, low extraction rate, and easy discoloration under light. However, the latest research shows that glabridin has a significant whitening effect, has a strong inhibitory ability on tyrosinase, can show a good whitening effect at low concentrations, and is not easy to cause pigment rebound.

[0009] Pterostilbene is a trans-diphenylethylene compound naturally present in plants such as rosewood and rosewood, also known as rosewood bark extract. It is a powerful natural antioxidant, mainly manifested in reducing oxidative stress and reactive oxygen species (ROS), inhibiting the production of ROS, such as hydrogen peroxide and superoxide anions; it can fight against a variety of free radicals, such as DPPH, ABTS, hydroxyl, superoxide, etc.; in addition, pterostilbene has a strong ability to inhibit tyrosinase and melanin, and is light-stable and not easy to change color. When combined with glycyrrhizin, it can not only significantly reduce the cost of glycyrrhizin, but also has a synergistic and efficient whitening effect, and can help stabilize the discoloration and yellowing problem of glycyrrhizin.

[0010] As an auxiliary ingredient, stearyl glycyrrhetinate is a derivative of glycyrrhetinic acid. It has good transdermal absorption and anti-inflammatory capabilities. It also has the effects of whitening, strengthening the skin barrier, improving inflammatory pigmentation, and assisting in sun protection. Its addition to skin care products can enhance the moisturizing and whitening effects of the product while reducing irritation to the skin.

[0011] As an innovative whitening factor, tetrahydromethylpyrimidine carboxylic acid can protect the number of epidermal melanocytes in human skin irradiated by ultraviolet rays, thereby reducing cellular immunosuppression caused by ultraviolet rays. In addition, it can prevent photoaging by protecting epidermal melanocytes from damage caused by ultraviolet rays, inhibit the release of cellular inflammatory factors, enhance the vitality of fibroblasts, promote fibroblast proliferation, promote epidermal renewal, and help the shedding of melanin and skin regeneration.

[0012] Through experimental exploration, it was found that the present invention scientifically compounded four components to prepare a whitening composition. The four components cooperated with each other and influenced each other, synergistically enhancing the high-efficiency inhibitory effect of the composition on tyrosinase, and effectively hindering the oxidative stress of melanocytes, enhancing the skin barrier, improving inflammatory pigmentation, promoting cell proliferation and epidermal renewal, achieving a rapid and lasting whitening effect, while ensuring the mildness and stability of the product.

[0013] In addition, the inventors explored the dosage of each component and found that when the dosage of the four components is too small or the total dosage of the four is too small, the synergistic effect is not obvious, and when the dosage of the four components is too large or the total dosage of the four is too large, antagonism may occur, which will also lead to the effect of inhibiting tyrosinase activity and the decrease of antioxidant effect, indicating that the above four components have a more ideal synergistic effect when they are within the specified range of the present invention.

[0014] Preferably, the whitening composition comprises the following components in parts by weight: 0.02-0.08 parts of glabridin, 0.02-0.08 parts of pterostilbene, 0.05-0.16 parts of stearyl glycyrrhetinate and 0.1-0.2 parts of ectoine.

[0015] Preferably, the whitening composition comprises the following components in parts by weight: 0.05 parts of glabridin, 0.05 parts of pterostilbene, 0.1 parts of stearyl glycyrrhetinate and 0.2 parts of ectoine.

[0016] It has been found through experiments that when the four components of the present invention are combined in the optimal dosage ratio defined above, the obtained whitening composition has the best tyrosinase inhibition effect and the best DPPH clearance effect, thereby achieving a rapid and excellent whitening effect.

[0017] In a second aspect, the present invention provides use of the whitening composition in the preparation of whitening cosmetics.

[0018] In a third aspect, the present invention provides a whitening cosmetic comprising the whitening composition.

[0019] Preferably, the cosmetics include at least one of an aqueous solution, an essence, an emulsion, a facial cream, an eye cream, and a facial mask.

[0020] In a fourth aspect, the present invention provides a whitening essence, comprising the whitening composition, wherein the mass percentage of the whitening composition in the whitening essence is 0.12-0.6%.

[0021] Preferably, the whitening essence also includes 1-5% moisturizer, 0.03-0.05% chelating agent, 0.5-0.8% thickener, 0.2-5% emulsifier, 0.3-0.6% preservative, 3-5% polyol solvent and the balance water.

[0022] Preferably, the moisturizing agent comprises at least one of glycerin, polyglycerin, diglycerin, methylpropanediol, dipropylene glycol, betaine, trehalose, xylitol, sodium hyaluronate, hydrolyzed hyaluronic acid, and acetylated sodium hyaluronate β-glucan;

[0023] The chelating agent includes disodium EDTA and / or tetrasodium EDTA;

[0024] The thickener comprises at least one of carbomer, xanthan gum, polyacrylate crosspolymer-6, acrylic acid (ester) / C10-30 alkyl acrylate crosspolymer, ammonium acryloyldimethyltaurate / VP copolymer, sodium acrylic acid (ester) copolymer, lecithin, cetearyl alcohol and stearyl alcohol;

[0025] The emulsifier includes at least one of hydrogenated lecithin, sodium stearoyl glutamate, cetearyl glucoside, arachidyl glucoside, PEG-100 stearate and glyceryl stearate;

[0026] The preservative includes at least one of methylparaben, sodium benzoate, chlorphenesin, phenoxyethanol, potassium sorbate, p-hydroxyacetophenone and caprylhydroxamic acid;

[0027] The polyol solvent includes at least one of butanediol, 1,2-hexanediol, and 1,3-propylene glycol.

[0028] In a fifth aspect, the present invention provides a method for preparing the whitening essence, comprising the following steps:

[0029] (1) Mix water, moisturizer, chelating agent, thickener and emulsifier, stir and heat to 80-85° C., stir evenly to obtain material A;

[0030] (2) mixing glabridin, pterostilbene, stearyl glycyrrhetinate and a polyol solvent uniformly, and then heating the mixture to 45-60° C. until it is completely transparent to obtain material B;

[0031] (3) mixing the preservative and the polyol solvent evenly, and then heating the mixture to 45-60° C. until it becomes completely transparent, thereby obtaining material D;

[0032] (4) Add material B to material A, homogenize evenly, then cool to 45-50° C., add ectoine and material D, and stir evenly to obtain the whitening essence.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] (1) The present invention prepares a stable and efficient synergistic whitening composition by scientifically combining four components: glycyrrhizin, pterostilbene, stearyl glycyrrhetinate and tetrahydromethylpyrimidine carboxylic acid. The four components cooperate with each other to synergistically enhance the antioxidant free radical scavenging ability of the composition and the inhibitory effect of tyrosinase activity, thereby effectively reducing melanin deposition on the surface and deep layers of the skin, improving spots and uneven skin color, and also enhancing the skin's antioxidant ability and self-repair ability, reducing skin damage caused by ultraviolet rays;

[0035] (2) The whitening complex is safe, stable and mild, ensuring that it is applicable to a wide range of people and brings users a more comprehensive and effective skin care experience. It not only meets the market demand for efficient and safe whitening products, but also provides a new technical solution for the cosmetics industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 The facial comparison pictures of a user before and after using the whitening essence prepared in Example 5 for one month. DETAILED DESCRIPTION

[0037] 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. It should be understood by those skilled in the art that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0038] Unless otherwise specified, all raw materials involved in the following examples and comparative examples are commercially available general materials.

[0039] Examples 1-5

[0040] Table 1: Formula of the whitening essence described in Examples 1-5 (mass percentage %)

[0041]

[0042] Comparative Examples 1-8

[0043] Table 2: Formula of the whitening essence described in Comparative Examples 1-8 (mass percentage %)

[0044]

[0045]

[0046] Comparative Example 9

[0047] This comparative example provides a whitening essence, which is different from the whitening essence described in Example 5 in that pterostilbene is replaced with resveratrol in this comparative example, and other components and contents remain unchanged.

[0048] Comparative Example 10

[0049] This comparative example provides a whitening essence, which is different from the whitening essence described in Example 5 in that: in this comparative example, stearyl glycyrrhetinate is replaced by dipotassium glycyrrhizinate, and other components and contents remain unchanged.

[0050] The preparation method of the whitening essence described in Examples 1-5 and Comparative Examples 1-10 comprises the following steps:

[0051] (1) Mix water, moisturizer, chelating agent, thickener and emulsifier, stir and heat to 80-85° C., stir evenly to obtain material A;

[0052] (2) mixing glabridin, pterostilbene, stearyl glycyrrhetinate and a polyol solvent uniformly, and then heating the mixture to 45-60° C. until it is completely transparent to obtain material B;

[0053] (3) mixing the preservative and the polyol solvent evenly, and then heating the mixture to 45-60° C. until it becomes completely transparent, thereby obtaining material D;

[0054] (4) Add material B to material A, homogenize evenly, then cool to 45-50° C., add ectoine and material D, and stir evenly to obtain the whitening essence.

[0055] Effect example

[0056] 1. Antioxidant test

[0057] The whitening essences prepared in Examples 1-5 and Comparative Examples 1-10 were used as samples, and the in vitro antioxidant efficacy of the samples was evaluated by a DPPH free radical scavenging experiment. The specific method is as follows.

[0058] DPPH free radical scavenging rate calculation formula: scavenging rate (%) = [1-(Ai-Aj)Ac] × 100

[0059] Free radical scavenging experiment: Take 2mL of 0.2mM DPPH as the working solution as an example, where Ac is the absorbance value of 2mL 95% ethanol plus 2mL DPPH working solution; Ai is 2mL of the sample to be tested, add 2mL DPPH, mix well, react at room temperature in the dark for 30min, and measure the absorbance value at a wavelength of 517nm; Aj is the control, and the value is the absorbance value measured by adding 2mL of the solution of the test sample with the corresponding concentration to 2mL of anhydrous ethanol. In the experiment, each absorbance was measured separately, and the scavenging rate of the test sample on DPPH free radicals can be calculated by the above formula. The specific DPPH free radical scavenging rate results of the samples are shown in Table 3.

[0060] Table 3

[0061]

[0062] As can be seen from Table 3, the whitening composition of the present invention has a good DPPH free radical scavenging effect, thereby effectively reducing the oxidative stress of melanocytes, improving pigmentation, and achieving a stable and lasting whitening effect; when any one or more of the four components of glabridin, pterostilbene, stearyl glycyrrhetinate and tetrahydromethylpyrimidine carboxylic acid described in the present invention are lacking in Comparative Examples 1 and Comparative Examples 4-8, the DPPH free radical scavenging effect of the prepared whitening essence is significantly reduced, and when pterostilbene and stearyl glycyrrhetinate are replaced by other conventional components in Comparative Examples 9-10, the DPPH free radical scavenging effect of the prepared whitening essence is also reduced, indicating that there is an ideal synergistic effect between the above four components used in the present invention, and the cooperation between the four can significantly enhance the scavenging effect of DPPH free radicals, so that the product achieves good whitening and antioxidant effects, and the four components are indispensable.

[0063] 2. Tyrosinase inhibition test

[0064] The whitening essences prepared in Examples 1-5 and Comparative Examples 1-10 were used as samples, and the tyrosinase inhibition rate of each whitening essence sample of the present invention was determined by referring to the test method described in T / GDCA006-2021 Guangdong Cosmetics Association Group Standard "Test Method for Tyrosinase Activity Inhibition of Cosmetic Raw Materials (In Vitro Method)". The results are shown in Table 4.

[0065] Table 4

[0066]

[0067] As shown in Table 5, the whitening composition prepared by the technical solution of the present invention has a good effect of inhibiting tyrosinase activity, thereby effectively reducing the production of melanin and achieving an ideal whitening effect. In particular, the whitening composition prepared by the optimal dosage ratio defined in the present invention in Example 5 can make the tyrosinase inhibition rate of the essence product reach 94.6%, and the enzyme activity inhibition effect is significant. When any one or more of the four specific components described in the present invention are missing in Comparative Examples 1 and Comparative Examples 4-10, the tyrosinase inhibition rate of the prepared whitening essence is significantly reduced, and when the dosage ratio of the four components described in Comparative Examples 2-3 exceeds the range defined in the present invention, the tyrosinase inhibition rate of the prepared whitening essence is also weakened, indicating that when the dosage of the four components described in the present invention is too low in the whitening product, the synergistic whitening effect is not obvious, and when the dosage ratio of the four components is too high, antagonism may occur between the components, resulting in a reduction in the effect of inhibiting tyrosinase activity, affecting the stable and lasting whitening effect of the product.

[0068] 3. Stability test

[0069] The whitening essence prepared in Examples 1-5 and Comparative Examples 1-10 were used as samples, and were placed under high temperature (50°C) (equipment model: electric constant temperature incubator DHP-9272) and light for one month (equipment model: light source metal integrated light box HP60-5) to observe the heat resistance and light stability of the samples under the above test conditions. The specific results are shown in Table 5.

[0070] Table 5

[0071]

[0072] 4. Security Testing

[0073] The whitening essence prepared in Examples 1-5 and Comparative Examples 1-10 was used as a sample, and the samples were tested for safety according to the human skin patch test method in the "Cosmetic Safety Technical Specifications 2015 Edition". 30 testers who met the subject selection criteria were selected, and the samples of each embodiment and comparative example were applied to the back of the subjects according to the human skin patch test method, and the skin reactions were observed and the observation results were recorded according to the skin reaction grading standard of the skin occlusion patch test. Table 6 shows the grading standard of adverse skin reactions, and Table 7 shows the specific skin reaction results.

[0074] Table 6

[0075]

[0076] Table 7

[0077] Sample source Test Results Sample source Test Results Example 1 No stimulation Comparative Example 4 No stimulation Example 2 No stimulation Comparative Example 5 1 case of grade 1 reaction Example 3 No stimulation Comparative Example 6 1 case of grade 1 reaction Example 4 No stimulation Comparative Example 7 2 cases of grade 1 reactions Example 5 No stimulation Comparative Example 8 No stimulation Comparative Example 1 No stimulation Comparative Example 9 3 cases of grade 1 reactions Comparative Example 2 No stimulation Comparative Example 10 1 case of grade 1 reaction Comparative Example 3 No stimulation

[0078] As can be seen from Tables 6-7, the whitening composition of the present invention is safe, stable, mild, and has no adverse irritation reaction. However, due to the lack or replacement of pterostilbene in Comparative Examples 4 and 9, the active ingredient of glabridin in the product is oxidized and discolored, causing the product to oxidize and turn yellow or even reduce its activity under light or high temperature conditions, thereby affecting the user experience; in Comparative Examples 5-7, when stearyl glycyrrhetinate or tetrahydromethylpyrimidine carboxylic acid is lacking, and in Comparative Examples 9-10, when pterostilbene and stearyl glycyrrhetinate are replaced by other components, the obtained essence product exhibits a certain irritation, indicating that when pterostilbene, stearyl glycyrrhetinate and tetrahydromethylpyrimidine carboxylic acid are compounded with glabridin in the present invention, they can synergistically enhance the whitening effect of glabridin, so that the product has better whitening efficacy, thereby reducing production costs. At the same time, the three components can also effectively maintain the long-term stability of the product, and effectively alleviate or reduce the irritation of the product, so that the prepared whitening product is safe, stable and mild, thereby bringing users a more comprehensive and effective whitening skin care experience.

[0079] Figure 1 This is a comparison of the faces of the subjects before and after using the whitening essence prepared in Example 5 for one month. The sample was used on the cheeks of the subjects once in the morning and evening after cleansing the face, with a dosage of 1-2 ml, with a thin layer applied on the cheeks. After continuous use for one month, the problems of facial oxidation yellowing and uneven skin color of the subjects were effectively improved, and the whitening and brightening effects were obvious.

[0080] Finally, it should be noted that the above embodiments are intended 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 may 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, characterized in that: The whitening composition comprises the following components in parts by weight: 0.02-0.08 parts of glabridin, 0.02-0.08 parts of pterostilbene, 0.05-0.16 parts of stearyl glycyrrhetinate and 0.1-0.2 parts of ectoine.

2. The whitening composition according to claim 1, characterized in that The whitening composition comprises the following components in parts by weight: 0.05 parts of glabridin, 0.05 parts of pterostilbene, 0.1 parts of stearyl glycyrrhetinate and 0.2 parts of ectoine.

3. Use of the whitening composition as claimed in claim 1 or 2 in the preparation of whitening cosmetics.

4. A whitening cosmetic, characterized in that: The whitening cosmetic comprises the whitening composition according to claim 1 or 2.

5. The whitening cosmetic according to claim 4, characterized in that: The cosmetics include at least one of an aqueous solution, an essence, an emulsion, a facial cream, an eye cream, and a facial mask.

6. A whitening essence, characterized in that: The whitening essence comprises the whitening composition according to claim 1 or 2, and the mass percentage of the whitening composition in the whitening essence is 0.12-0.6%.

7. The whitening essence according to claim 6, characterized in that: The whitening essence also comprises 1-5% of moisturizing agent, 0.03-0.05% of chelating agent, 0.5-0.8% of thickening agent, 0.2-5% of emulsifier, 0.3-0.6% of preservative, 3-5% of polyol solvent and the balance of water.

8. The whitening essence according to claim 7, characterized in that The moisturizing agent includes at least one of glycerin, polyglycerin, diglycerin, methylpropanediol, dipropylene glycol, betaine, trehalose, xylitol, sodium hyaluronate, hydrolyzed hyaluronic acid, and acetylated sodium hyaluronate β-glucan; The chelating agent includes disodium EDTA and / or tetrasodium EDTA; The thickener comprises at least one of carbomer, xanthan gum, polyacrylate crosspolymer-6, acrylic acid (ester) / C10-30 alkyl acrylate crosspolymer, ammonium acryloyldimethyltaurate / VP copolymer, sodium acrylic acid (ester) copolymer, lecithin, cetearyl alcohol and stearyl alcohol; The emulsifier includes at least one of hydrogenated lecithin, sodium stearoyl glutamate, cetearyl glucoside, arachidyl glucoside, PEG-100 stearate and glyceryl stearate; The preservative includes at least one of methylparaben, sodium benzoate, chlorphenesin, phenoxyethanol, potassium sorbate, p-hydroxyacetophenone and caprylhydroxamic acid; The polyol solvent includes at least one of butanediol, 1,2-hexanediol, and 1,3-propylene glycol.

9. The method for preparing the whitening essence according to any one of claims 6 to 8, characterized in that: The following steps are involved: (1) Mix water, moisturizer, chelating agent, thickener and emulsifier, stir and heat to 80-85° C., stir evenly to obtain material A; (2) mixing glabridin, pterostilbene, stearyl glycyrrhetinate and a polyol solvent uniformly, and then heating the mixture to 45-60° C. until it is completely transparent to obtain material B; (3) mixing the preservative and the polyol solvent evenly, and then heating the mixture to 45-60° C. until it becomes completely transparent, thereby obtaining material D; (4) Add material B to material A, homogenize evenly, then cool to 45-50° C., add ectoine and material D, and stir evenly to obtain the whitening essence.

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