Whitening composition and essence containing same

Abstract

The invention relates to a whitening composition and essence containing the same. The whitening composition comprises the following components in percentage by mass: 1-2% of glabridin, 20-30% of an emulsifier, 35-45% of a solubilizer and the balance of water, the essence containing the whitening composition comprises the following components in percentage by mass: 1-5% of the whitening composition, 0.1-0.5% of sodium alginate, 1-10% of a humectant, 1-5% of a penetration enhancer, 0.1-1% of a skin conditioner, 0.4-1% of a preservative and the balance of water. By adding the emulsifier and the solubilizer, the problems of poor water solubility and poor stability of glabridin are solved, meanwhile, the effect of glabridin is reserved, and an essence product prepared from the whitening composition has good antioxidant and whitening effects and still has the whitening effect under the extremely low addition amount.

Description

Technical Field

[0001] The invention belongs to the technical field of skin care functional products, and particularly relates to a whitening composition and an essence containing the composition. Background Art

[0002] With the increasing demand for anti-freckle and whitening cosmetics, more and more active ingredients are added to skin care products as whitening raw materials, but there are problems such as poor solubility and high irritation.

[0003] Glabridin is a flavonoid extracted from licorice or Glycyrrhiza glabra. It can scavenge free radicals and inhibit tyrosinase activity. It is often used in whitening skin care products and is known as "whitening gold". Glabridin is insoluble in water and has poor high-temperature stability, which limits its application in some water-based products. Currently, there are some water-soluble glabridin complexes on the market, most of which are encapsulated by hydroxypropyl cyclodextrin, which solves the problem of poor water solubility of glabridin. However, after encapsulation, the whitening effect of glabridin is weakened. Therefore, increasing the solubility and stability of glabridin is of great significance to broadening the application range of glabridin.

[0004] Sodium alginate is a commonly used medical dressing with high hygroscopicity. It can provide a moist healing environment for wounds and is conducive to the regeneration of skin tissue. Sodium alginate has a high molecular weight and a rigid structure. Even at low concentrations, its aqueous solution has a very high apparent viscosity. It is often used as a moisturizer and thickener in skin care products, but little research has been done on its whitening effect. Summary of the invention

[0005] The purpose of the present invention is to provide a whitening composition and an essence containing the composition, which not only solves the problem of poor water solubility of glabridin, but also retains the efficacy of glabridin and has good whitening efficacy.

[0006] The technical solution adopted by the present invention to solve the above problems is: a whitening composition, comprising the following components in percentage by mass: 1-2% of glabridin, 20-30% of emulsifier, 35-45% of solubilizer, and the balance of water.

[0007] Preferably, the emulsifier is polysorbate-20 or polysorbate-80; polysorbate-20 and polysorbate-80 are a type of non-ionic emulsifiers, which contain more hydrophilic groups and can evenly disperse glabridin in an aqueous solution to fully exert its efficacy.

[0008] Preferably, the solubilizer is a compound of PEG-40 hydrogenated castor oil and diol in a mass ratio of 5-10:25-35. The solubilizer is used together with the emulsifier to increase the stability of the system. The addition of the solubilizer avoids the turbidity of the aqueous solution after emulsification with a single emulsifier when heated. Among them, the compatibilizer uses a compound of diol and castor oil to avoid the drawbacks of using castor oil alone, such as excessive irritation and low-temperature turbidity of the product due to high freezing point.

[0009] Preferably, the diol is at least one of butanediol, propylene glycol and dipropylene glycol.

[0010] A method for preparing a whitening composition comprises the following steps:

[0011] (1) Weigh the materials according to the mass percentage of the raw materials;

[0012] (2) Add glabridin to the emulsifier, heat and stir at low temperature, slowly add water, and then add a solubilizer until a transparent and uniform solution is obtained, and cool to room temperature to obtain a glabridin whitening composition.

[0013] An essence containing the whitening composition comprises the following components in percentage by weight: 1-5% of the whitening composition, 0.1-0.5% of sodium alginate, 1-10% of a moisturizer, 1-5% of a penetration enhancer, 0.1-1% of a skin conditioner, 0.4-1% of a preservative, and the remainder being water.

[0014] Preferably, the moisturizing agent is a mixture of high molecular weight sodium hyaluronate and polyols. The hydroxyl groups of the polyols absorb moisture in the environment, combined with the water-locking function of hyaluronic acid, to provide a good moisturizing effect for the skin.

[0015] More preferably, the molecular weight of the sodium hyaluronate is 1700~1750K Da.

[0016] Preferably, the penetration enhancer is dimethyl isosorbide, which can dissolve free fat in the skin, thereby penetrating the skin membrane, promoting the penetration of whitening active ingredients into the epidermis, and giving full play to the efficacy of the whitening composition.

[0017] Preferably, the skin conditioner is at least one of Portulaca oleracea extract or Centella asiatica extract, which can relieve skin irritation, inhibit inflammatory mediators, and avoid darkening caused by melanin synthesis mediated by inflammatory cytokines.

[0018] Among them, sodium alginate is used as a thickener and whitening agent, and has certain thickening and whitening effects.

[0019] Compared with the prior art, the advantages of the present invention are:

[0020] The present invention prepares water-insoluble glabridin into a water-soluble whitening composition, and solves the problems of poor solubility and poor stability by adding an emulsifier and a solubilizer. The essence product prepared by using the whitening composition has good antioxidant and whitening effects, and still has the whitening effect at an extremely low addition amount. DETAILED DESCRIPTION

[0021] The present invention is further described in detail below with reference to the embodiments.

[0022] Example 1

[0023] The materials were weighed according to the mass percentage of the raw materials in Table 1, and glabridin was added to polysorbate-20. The mixture was heated and stirred at low temperature (45°C), and water was slowly added. Then, PEG-40 hydrogenated castor oil and dipropylene glycol were added until a transparent and uniform solution was obtained. The mixture was cooled to room temperature to obtain a glabridin whitening composition.

[0024] Table 1 Raw materials of the whitening composition of the embodiment

[0025] Serial number Raw material name Ratio% (w / w) 1 Glabridin 1 2 Polysorbate 20 20 3 PEG-40 Hydrogenated Castor Oil 8 4 Dipropylene glycol 30 5 water 41

[0026] Comparative Example 1

[0027] The only difference from Example 1 is that only 38% PEG-40 hydrogenated castor oil is added, and no dipropylene glycol is added.

[0028] After the whitening compositions obtained in Example 1 and Comparative Example 1 were placed at 4° C. for 24 hours, it was observed that Example 1 was still a liquid with strong fluidity, while Comparative Example 1 had solidified into a viscous liquid with very low fluidity, and heating was required to increase its fluidity in actual application, indicating that Example 1 was more suitable for application in actual product formulations.

[0029] Comparative Example 2

[0030] The only difference from Example 1 is that only 38% of dipropylene glycol is added, and no hydrogenated castor oil is added.

[0031] After the whitening compositions of Example 1 and Comparative Example 2 were diluted 1000 times with purified water, granular insoluble matter precipitated in Comparative Example 2, while Example 1 remained transparent and clear, indicating that Example 1 is more suitable for application in actual product formulations to avoid the precipitation of effective ingredients and affecting product stability.

[0032] Example 2

[0033] The glabridin whitening composition was prepared according to the mass percentage of the raw materials in Table 1.

[0034] An essence comprising the above whitening composition, comprising the following components in the following mass percentages:

[0035] 200 mesh sodium alginate 0.3%

[0036] 1700~1750K Da Sodium Hyaluronate 0.05%

[0037] Dipropylene glycol 7%

[0038] Isosorbide dimethyl ether 5%

[0039] Purslane extract 0.3%

[0040] Whitening composition 1%

[0041] Preservative (p-hydroxyacetophenone) 0.5%

[0042] Water Remaining

[0043] A method for preparing an essence comprising the above whitening composition is as follows:

[0044] Weigh the materials according to the above mass percentages, add water, sodium alginate and sodium hyaluronate into a stirring pot, and stir homogenously at a constant temperature of 70°C for 20 minutes to make them swell completely; then add dipropylene glycol and dimethyl isosorbide, and stir for 10 minutes; turn on the cooling and reduce the temperature to 45°C, add purslane extract, whitening composition and preservatives, and stir for 15 minutes to make them evenly dispersed; cool to room temperature, degas and filter to obtain the whitening essence.

[0045] Example 3

[0046] The materials were weighed according to the mass percentages of the raw materials in Table 2, glabridin was added to polysorbate-20, heated and stirred at low temperature (45°C), water was slowly added, and then PEG-40 hydrogenated castor oil and dipropylene glycol were added until a transparent and uniform solution was obtained, and the solution was cooled to room temperature to obtain a glabridin whitening composition.

[0047] Table 2 Raw materials of the whitening composition of the embodiment

[0048] Serial number Raw material name Ratio% (w / w) 1 Glabridin 1.1 2 Polysorbate 20 22 3 PEG-40 Hydrogenated Castor Oil 10 4 Butanediol 30 5 water 36.9

[0049] An essence comprising the above whitening composition, comprising the following components in the following mass percentages:

[0050] 200 mesh sodium alginate 0.3%

[0051] 1700~1750K Da Sodium Hyaluronate 0.05%

[0052] Dipropylene glycol 7%

[0053] Isosorbide dimethyl ether 5%

[0054] Purslane extract 0.3%

[0055] Whitening composition 1%

[0056] Preservative (phenoxyethanol) 0.8%

[0057] Water Remaining

[0058] A method for preparing an essence comprising the above whitening composition is as follows:

[0059] Weigh the materials according to the above mass percentages, add water, sodium alginate and sodium hyaluronate into a stirring pot, and stir homogenously at a constant temperature of 70°C for 20 minutes to make them swell completely; then add dipropylene glycol and dimethyl isosorbide, and stir for 10 minutes; turn on the cooling and reduce the temperature to 45°C, add purslane extract, whitening composition and preservatives, and stir for 15 minutes to make them evenly dispersed; cool to room temperature, degas and filter to obtain the whitening essence.

[0060] Example 4

[0061] The materials were weighed according to the mass percentages of the raw materials in Table 3, glabridin was added to polysorbate-20, heated and stirred at low temperature (45°C), water was slowly added, and then PEG-40 hydrogenated castor oil and dipropylene glycol were added until a transparent and uniform solution was obtained, and the solution was cooled to room temperature to obtain a glabridin whitening composition.

[0062] Table 3 Raw materials of the whitening composition of the embodiment

[0063] Serial number Raw material name Ratio% (w / w) 1 Glabridin 1.2 2 Polysorbate 20 25 3 PEG-40 Hydrogenated Castor Oil 10 4 Dipropylene glycol 35 5 water 28.8

[0064] An essence comprising the above whitening composition, comprising the following components in the following mass percentages:

[0065] 200 mesh sodium alginate 0.3%

[0066] 1700~1750K Da Sodium Hyaluronate 0.05%

[0067] Dipropylene glycol 7%

[0068] Isosorbide dimethyl ether 5%

[0069] Purslane extract 0.3%

[0070] Whitening composition 1%

[0071] Preservative (raspberry ketone) 0.4%

[0072] Water Remaining

[0073] A method for preparing an essence comprising the above whitening composition is as follows:

[0074] Weigh the materials according to the above mass percentages, add water, sodium alginate and sodium hyaluronate into a stirring pot, and stir homogenously at a constant temperature of 70°C for 20 minutes to make them swell completely; then add dipropylene glycol and dimethyl isosorbide, and stir for 10 minutes; start cooling and reduce the temperature to about 45°C, add purslane extract, whitening composition and preservatives, and stir for 10-15 minutes to make them evenly dispersed; cool to room temperature, degas and filter to obtain whitening essence.

[0075] The whitening composition of Example 2-4 was tested for tyrosinase inhibition rate, as follows:

[0076] Referring to the Shanghai Daily Chemical Industry Association group standard T / SHRH 015-2018, the inhibitory effect of the glabridin whitening composition on tyrosinase activity was evaluated.

[0077] The whitening composition was diluted with sodium hydrogen phosphate-citric acid buffer to a multi-level concentration sample, and the encapsulated glabridin was used as a reference. Referring to Table 4, a 10mL test tube was used to set up the sample tube (T), sample background (T0), enzyme reaction tube (C) and solvent background (C0). Three parallel tubes were required for each sample tube (T) of each tested concentration, and three parallel tubes were required for the enzyme reaction tube (C). 1mL of sample solution of the same concentration was added to the sample tube (T) and sample background (T0), and 1mL of sodium hydrogen phosphate-citric acid buffer was added to the enzyme reaction tube (C) and solvent background (C0). 0.5mL of tyrosinase solution was added to the sample tube (T) and enzyme reaction tube (C), and the sample background (T0) and solvent background (C0) were replaced with 0.5mL of sodium hydrogen phosphate-citric acid buffer. The sample and tyrosinase were fully mixed and incubated in a 37°C water bath for 10 minutes. 2 mL of L-DOPA solution was added to each tube in turn, and the reaction time of each tube was controlled to be 5 minutes. The reaction solution of each tube was immediately transferred to a cuvette, and the absorbance value was measured at 475 nm.

[0078] Table 4 Sample addition requirements

[0079] T-sample tube <![CDATA[T0 - Sample background]]> C-enzyme reaction tube <![CDATA[C0 - Solvent background]]> Sample solution (ml) 1 1 Disodium hydrogen phosphate-citrate buffer (ml) 0.5 1 1.5 Tyrosinase solution (ml) 0.5 0.5 Levodopa solution (ml) 2 2 2 2 Parallel times 3 / Sample 1 / sample 3 / Experimental 1 / Experiment

[0080] Calculate the tyrosinase inhibition rate:

[0081] Inhibition rate (%) = (1- )×100%

[0082] Where: T—absorbance of sample tube, i.e. absorbance of solution after sample reacts with tyrosinase;

[0083] T0—sample background absorbance;

[0084] C—the average value of the absorbance of the enzyme reaction tube three times, that is, the absorbance of the reaction of tyrosinase and DOPA when no sample is added;

[0085] C0—Solvent background absorbance.

[0086] The tyrosinase inhibition rate results of the whitening composition are shown in the following table:

[0087] Whitening composition concentration % (w / w) 0.0005 0.005 0.05 0.5 5 Example 2 Tyrosinase inhibition rate % 46.47 49.46 86.08 92.97 94.04 Example 3 Tyrosinase inhibition rate % 47.80 49.75 89.94 95.71 96.78 Example 4 Tyrosinase inhibition rate % 48.70 49.78 92.29 97.39 98.19

[0088] The results of tyrosinase inhibition rate of encapsulated glabridin are shown in the following table:

[0089] Concentration of encapsulated glabridin % (w / w) 0.001 0.01 0.1 1 5 Tyrosinase inhibition rate% 30.54 44.90 69.28 75.92 74.30

[0090] From the data in the table, it can be seen that the whitening composition prepared in Examples 2 to 4 can achieve an inhibition rate of more than 90% on tyrosinase at an addition amount of 0.5% (5 mg / ml); in Example 1, at an addition amount of 0.0005% (5 μg / ml), the content of glabridin is 5 μg / ml, and the inhibition rate on tyrosinase can reach more than 45%. However, when the encapsulated glabridin is added at 1% and 5%, the inhibition rate on tyrosinase is only about 75%, indicating that when the content is ≥1%, its inhibition rate on tyrosinase no longer increases with the increase in concentration. At the same concentration, the whitening composition prepared by the emulsification method is better than the encapsulated glabridin, and the composition has a good tyrosinase inhibition effect. At extremely low content, it can still inhibit the activity of tyrosinase, and during the dilution process, the composition dilution can still remain clear without precipitation of insoluble matter.

[0091] The essence in Example 2-4 was tested for PTIO free radical scavenging rate, as follows:

[0092] The whitening essence is appropriately diluted with water to serve as the sample solution to be tested.

[0093] Take 800μL of "PTIO test solution" and add a small amount of sample solution to it. When adding the sample, add a small amount first and then gradually add more. Mix while adding and observe the fading of the solution. If it does not fade immediately, observe it again after 2 hours in a 37℃ water bath. When the color of the solution basically fades, record the amount of sample added. This amount of sample added is the maximum amount of the sample. Based on this maximum amount, set 5 amounts forward to form an arithmetic progression.

[0094] Use a pipette to take 800 μL of "PTIO test solution" and add it to the cuvette, add x μL of sample solution, and then add (200-x) μL of water to mix, place in a 37°C water bath (or oven) for 30 minutes, and measure the A557nm value.

[0095] The sample addition table is shown in Table 5:

[0096] Table 5

[0097] Sample solution water PTIO test fluid Total volume 0 μL 200 μL 800 μL 1000μL 40 μL 160 μL 800 μL 1000μL 80 μL 120 μL 800 μL 1000μL 120 μL 80 μL 800 μL 1000μL 160 μL 40 μL 800 μL 1000μL 200μL 0 μL 800 μL 1000μL

[0098] PTIO • Calculation of clearance rate (inhibition rate):

[0099]

[0100] (A0 is the value without adding sample; A is the value after adding sample).

[0101] The essences in Examples 1-3 were tested for DPPH free radical scavenging rate, as follows:

[0102] Referring to the national standard GB / T39100-2020, the scavenging rate of whitening essence on DPPH free radicals was evaluated.

[0103] Take 3 test tubes, numbered 1, 2, and 3, and add reagents to each test tube according to the combination in the table.

[0104] Solution name No. 1 (As) No. 2 (Ac) No. 3 (Ab) DPPH solution 3ml - 3ml Sample solution 1ml 1ml - water - - 1ml Anhydrous ethanol solution - 3ml -

[0105] Test tube No. 1 was used as the test group (As), test tube No. 2 was used as the control group (Ac), and test tube No. 3 was used as the blank group (Ab). After being fully mixed, the mixture was reacted at room temperature in the dark for 30 minutes, and the absorbance was measured by an ultraviolet spectrophotometer at a wavelength of 517 nm (sample solvent was adjusted to zero for calibration).

[0106] DPPH free radical scavenging rate calculation:

[0107] P = (1 - )×100%

[0108] Where:

[0109] P: Clearance

[0110] As: absorbance of the mixture of the test solution and DPPH solution

[0111] Ac: absorbance of the mixture of the test solution and anhydrous ethanol solution

[0112] Ab: absorbance of the mixture of DPPH solution and sample solvent solution

[0113] The results of free radical scavenging rate of whitening essence PTIO are as follows:

[0114] Sample concentration (mg / ml) 2 4 6 8 10 20 30 40 50 Example 2 PTIO·Free Radical Scavenging Rate % 8.47 11.17 13.55 15.50 15.93 19.52 22.24 25.30 26.36 Example 3 PTIO·Free Radical Scavenging Rate % 9.49 11.81 13.75 15.68 16.19 20.05 23.44 25.39 28.57 Example 4 PTIO·Free Radical Scavenging Rate % 9.74 12.19 14.00 16.14 16.24 20.62 23.61 25.78 28.67

[0115] The results of the DPPH free radical scavenging rate of the whitening essence are as follows:

[0116] Sample concentration (mg / ml) 6 7 8 9 10 Example 2 DPPH·Free Radical Scavenging Rate % 45.24 49.57 52.1 55.76 58.42 Example 3DPPH·Free Radical Scavenging Rate% 45.36 50.37 53.47 56.54 59.88 Example 4 DPPH·Free Radical Scavenging Rate % 47.46 51.00 54.90 57.84 60.97

[0117] From the free radical scavenging rate results, it can be seen that the whitening essence has a certain scavenging effect on ROS and RNS. In addition to the whitening effect, it also has a certain anti-aging effect.

[0118] In addition to the above embodiments, the present invention also includes other implementation modes. Any technical solutions formed by equivalent transformation or equivalent replacement should fall within the protection scope of the claims of the present invention.

Claims

1. A whitening composition, characterized in that: The invention comprises the following components in the following mass percentages: 1-2% of glabridin, 20-30% of emulsifier, 35-45% of solubilizer and the balance of water.

2. The whitening composition according to claim 1, characterized in that: The emulsifier is polysorbate-20 or polysorbate-80.

3. The whitening composition according to claim 1, characterized in that: The solubilizer is a compound of PEG-40 hydrogenated castor oil and diol in a mass ratio of 5-10:25-35.

4. The whitening composition according to claim 3, characterized in that: The diol is at least one of butanediol, propylene glycol and dipropylene glycol.

5. A method for preparing the whitening composition according to any one of claims 1 to 4, characterized in that: The following steps are involved: (1) Weigh the materials according to the mass percentage of the raw materials; (2) Add glabridin to the emulsifier, heat and stir at low temperature, slowly add water, and then add a solubilizer until a transparent and uniform solution is obtained, and cool to room temperature to obtain a glabridin whitening composition.

6. An essence comprising the whitening composition according to any one of claims 1 to 4, characterized in that: The invention comprises the following components in percentage by weight: 1-5% of a whitening composition, 0.1-0.5% of sodium alginate, 1-10% of a moisturizing agent, 1-5% of a penetration enhancer, 0.1-1% of a skin conditioning agent, 0.4-1% of a preservative, and the balance of water.

7. The essence according to claim 6, characterized in that: The moisturizing agent is a mixture of high molecular weight sodium hyaluronate and polyols.

8. The essence according to claim 7, characterized in that: The molecular weight of the sodium hyaluronate is 1700-1750 KDa.

9. The essence according to claim 6, characterized in that: The penetration enhancer is dimethyl isosorbide.

10. The essence according to claim 6, characterized in that: The skin conditioning agent is at least one of a purslane extract or a Centella asiatica extract.

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