JPH092967A - Tyrosinase activity inhibitor and cosmetics containing the same - Google Patents

Abstract

(57) [Summary] [Purpose] A tyrosinase activity inhibitor that achieves effective utilization of prune kernels and has an excellent skin whitening effect, and a feeling of use,
It is intended to provide a cosmetic containing a tyrosinase activity inhibitor, which has good stability and is safe to handle. [Structure] Tyrosinase activity inhibitor obtained by using prune kernel and an extract extracted by means of an extraction solvent as an active ingredient, and tyrosinase activity inhibition obtained by using water, ethanol or a mixture of water and ethanol as an extraction solvent Cosmetics containing an agent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tyrosinase activity inhibitor involved in melanin production and a cosmetic containing the same.

[0002]

The darkening phenomenon of skin due to spots, freckles, sunburn, etc. is due to the synthesis of melanin in melanocytes present in the basal cell layer of the epidermis. It has been confirmed that melanin is formed through cytoplasmic granules in melanocytes, tyrosine is oxidized by tyrosinase in melanosomes, and intermediates such as dopa, dopaquinone, and then 5,6-dihydroxyindole.

Therefore, it has been attempted to suppress the production of melanin by using a substance that inhibits the activity of tyrosinase to prevent the darkening phenomenon of the skin due to spots, freckles, sunburn, etc., and ascorbic acid and hydrogen peroxide have hitherto been used. , Glutathione, colloidal sulfur, hydroquinone and other substances have been incorporated into cosmetics.

[0004]

However, ascorbic acids are easily oxidized and unstable, and hydrogen peroxide is insufficient in storage stability and handling safety. In addition, glutathione and colloidal sulfur have a drawback that they cause a peculiar offensive odor and precipitation, and hydroquinone is not always satisfactory because it has problems with skin safety such as skin irritation and allergenicity.

Therefore, the fruits of prune (Prunus domestica LINN .., which are called Japanese plum or European plum) in the family Rosaceae, Prunus domestica LINN. In addition to being widely used as a dietary supplement, the water-extracted extract of dried fruits is widely known as a dietary supplement, but we have conducted diligent research focusing on the fact that effective use of prunes has not been reported yet. As a result, they found that pruned kernels had a particularly high tyrosinase inhibitory activity, and completed the present invention.

The object of the present invention is to solve the above-mentioned problems, to have an excellent skin whitening effect, and to have storage stability,
It is intended to provide a tyrosinase activity inhibitor obtained from prune kernel which is safe for handling and for living body and skin, and a cosmetic containing the same.

[0007]

According to the present invention, a tyrosinase activity inhibitor containing an extract extracted from prune kernels using an extraction solvent as an active ingredient and a crushed product of prune kernels are immersed in an extraction solvent for extraction. A tyrosinase activity inhibitor containing an extract as an active ingredient, a cosmetic containing these tyrosinase activity inhibitors, wherein water, hot water or a hydrophilic organic solvent or a mixture thereof is used as the extraction solvent, and prune It is a cosmetic containing milk extracted from nin as an active ingredient.

The prune kernels used in the present invention may be those obtained from raw fruits or those obtained from dried fruits.

The extraction means is not limited to the above, but is not particularly limited as long as it is a solvent capable of effectively extracting the active ingredient, but lower aliphatic alcohols such as ethanol and acetone are preferable. When used in cosmetics, water, ethanol or a mixture of water and ethanol is most preferable from the viewpoint of handling and safety to the living body and the skin.

The extract is obtained by crushing pruned kernels in an extraction solvent, stirring and extracting at room temperature (15 to 25 ° C.) for several days, and then filtering or centrifuging to remove solids. The obtained extract can be blended into cosmetics as it is, but depending on the method of use, a powder obtained by freeze-drying the extract may be blended, or the milk extracted by squeezing the prune kernels can be used as it is. You may use.

The cosmetic of the present invention is produced by a conventional method. In addition to the compound of the tyrosinase activity inhibitor, the components used in ordinary cosmetics, for example, oils, surfactants, Buffer, water, lower alcohol,
Beauty ingredients such as polyhydric alcohol, powder, moisturizer, thickener,
Dyes, fragrances, antioxidants, ultraviolet absorbers, chelating agents and the like can be added within a range that does not impair the tyrosinase inhibitory activity effect.

The above cosmetics are not limited to general skin cosmetics, but include quasi drugs and medicated cosmetics, and their dosage forms are cream, emulsion, lotion, face wash, Foundation, pack, powder, etc. are optional depending on the purpose.

[0013]

EXAMPLES The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to the following examples.

Example 1: Extraction of a water / ethanol mixture of pruned kernels 12.5 g of ground prune kernels 40 g of 50 (W / W)% ethanol
Was added for 3 days at room temperature (15 to 25 ° C) with stirring to extract, and then the solid matter was removed by centrifugation to obtain an extract (evaporation residue
2.52W / V%).

[Inhibition of tyrosinase activity] The skin whitening effect of the extract obtained in Example 1 was evaluated by the following evaluation method using the activity of inhibiting the activity of an enzyme involved in melanin production, that is, tyrosinase as an index.

[Preparation of sample and reagent] Sample solution: Prune kernel extract is diluted to an arbitrary concentration with 50 (W / W)% ethanol. Enzyme solution: Mushroom-derived tyrosinase (manufactured by Sigma) is diluted to 2500 units / ml with purified water. Substrate solution: L-tyrosine (manufactured by Wako Pure Chemical Industries, Ltd.) 15
Dissolve mg in purified water to a total volume of 100 ml. Buffer: 1 / 15M phosphate buffer (pH 6.8) 0.4999g monopotassium phosphate and 0.5214g dipotassium phosphate
Is dissolved in 100 ml of purified water to pH 6.8.

[Measurement of tyrosinase activity inhibition] In a test tube, 1 ml of the above sample solution, 1 ml of substrate solution and 1 m of buffer solution were placed.
l, and pre-incubate at 37 ° C for 5 minutes, add 0.1 ml of enzyme solution, incubate for 20 minutes to react, and immediately set the absorbance at 475 nm measured with a spectrophotometer to A. As a control, instead of the sample solution
Add 1 ml of 50 (W / W)% ethanol and perform the same operation, and call this absorbance B. As a blank, 0.1 ml of purified water is added instead of the enzyme solution, the same operation is performed, and this absorbance is designated as C.

From these values, the tyrosinase activity inhibition rate (%) was calculated by the following formula.

## EQU1 ## Inhibition rate (%) = [[B− (A−C)] / B] ×
100

FIG. 1 shows the concentration dependence of the tyrosinase activity inhibitory effect of the sample. The concentration (IC ₅₀ , mg / ml) at which the tyrosinase activity was inhibited by 50% was determined from this, and Table 1
It was shown to.

[0020]

[Table 1] As is clear from Table 1, the product of the present invention was found to inhibit tyrosinase activity at a lower concentration than L-ascorbic acid.

[Melanin production inhibitory effect] The melanin production inhibitory effect of the extract obtained in Example 1 by the action of tyrosinase was evaluated by the following evaluation methods.

[Preparation of Samples and Reagents] Sample Solution: Prune kernel extract is diluted to an arbitrary concentration with 50 (W / W)% ethanol. Enzyme solution: Mushroom-derived tyrosinase (manufactured by Sigma) is diluted to 156 units / ml with purified water. Substrate solution: L-tyrosine (manufactured by Wako Pure Chemical Industries, Ltd.) 50
Dissolve mg in purified water to a total volume of 50 ml. Copper sulfate solution: 1 g of copper sulfate (manufactured by Wako Pure Chemical Industries, Ltd.) is dissolved in purified water to make 100 ml. Buffer: 1 / 15M phosphate buffer (pH 6.8) 0.4999 g monopotassium phosphate and 0.5214 dipotassium phosphate
g Dissolve in 100 ml of purified water and adjust to pH 6.8.

[Measuring Method of Melanin Production Inhibitory Action] 2 ml of the sample solution, 0.5 ml of the substrate solution and 2 ml of the buffer solution are put in a test tube, 0.05 ml of a copper sulfate solution is further added, and the mixture is shaken vigorously and left for 10 minutes. Then 0.5 ml of enzyme solution
Is added and incubated for 1 hour, and the absorbance at 640 nm measured by a spectrophotometer is designated as A. As a control,
2% of 50 (W / W)% ethanol was added instead of the sample solution, and the same operation was performed, and this absorbance was designated as B. As a blank, 0.5 ml of purified water was added instead of the enzyme solution, the same operation was performed, and this absorbance was designated as C.

From these values, the melanin production rate (%) when the production amount of melanin in the control was 100% was calculated by the following formula, and the melanin production inhibitory effect of the sample solution was observed.

[Equation 2] Melanin production rate (%) = [(AC) / (B-
C)] × 100

FIG. 2 shows the concentration dependence of the melanin production inhibitory effect of the sample.
The concentration (IC ₅₀ , mg / ml) at which the concentration was suppressed to 50% was determined and is shown in Table 2.

[0026]

[Table 2] As is clear from Table 2, it was found that the product of the present invention suppressed the production of melanin at a lower concentration than L-ascorbic acid.

[Whitening Practical Test] A comparison between the cosmetic cream of the present invention shown in Example 3 below and the same amount of purified water as in Example 3 instead of the prune kernel extract (Example 1). The cosmetic cream of the example was subjected to a use test to evaluate its whitening effect.

[Evaluation method] During the summer from 2:00 pm to 3:00 pm, for 3 days (1 hour a day for a total of 3 hours), the subjects 10
For the skin on the forearm flexor side of a subject exposed to sunlight, the cosmetic cream of Example 3 was compared to the skin on the left side of the forearm flexor on the day exposed to the sunlight, and the skin on the right side was compared. The example cosmetic cream was applied once a day once in the morning and continuously for 12 weeks, and the effect of improving the pigmentation due to sunburn was evaluated by visual observation. Table 3 shows the results.

[0029]

[Table 3]

As is clear from Table 3, it was confirmed that the cream of Example 3 containing the prune kernel extract was obviously effective as compared with the comparative example. In addition, during the test period, it was confirmed that there was no unfavorable phenomenon to the skin such as irritation or rash at the sample application site and it was safe for the skin.

Example 2: Preparation method of lotion A lotion having the following composition was prepared by the method described below. [Composition] (% by weight) (1) Glycerin 5.0 (2) 1,3 Butylene glycol 4.0 (3) Oleyl alcohol 0.1 (4) Polyoxyethylene sorbitan monolaurate (20 EO) 1. 5 (5) Polyoxyethylene lauryl ether (20 EO) 0.5 (6) Ethanol 10.0 (7) Prune kernel extract (Example 1) 1.0 (8) Fragrance 0.1 (9) Protective Suitable amount of preservative (10) Residual amount of purified water

[Preparation Method] a. (1), (2) and (9) are added to (10) and dissolved at room temperature to give A. b. On the other hand, (3) to (6) and (8) are added and dissolved at room temperature to give B. c. Further, B is added to A to solubilize, (7) is added and filtered to obtain a product.

Example 3: Method for producing cosmetic cream [composition] (% by weight) (1) Stearic acid 14.0 (2) Vaseline 2.0 (3) Self-emulsifying glyceryl monostearate 2.5 (4) ) Polyoxyethylene sorbitan monostearate (20 EO) 1.5 (5) Prune kernel extract (Example 1) 1.0 (6) Flavor 0.1 (7) Preservative proper amount (8) 1,3 Butylene glycol 10.0 (9) Carboxyvinyl polymer 0.2 (10) Sodium hydroxide 0.06 (11) Purified water Residual amount

[Preparation Method] a. (7) to (11) are mixed and dissolved and heated to 70 ° C., and this is designated as C. b. Mix (1) to (4) and heat to 70 ° C., and call this D. c. Add D to C, stir, and homogenize with a homomixer, cool to 50 ℃ with stirring, add (5) and (6) to this, and cool to 30 ℃ with further stirring. .

Example 4: Manufacturing method of cosmetic emulsion [composition] (% by weight) (1) Prune milk juice 80.0 (2) Quince extract 16.0 (3) Preservative proper amount (4) Purified water residue amount

[Preparation method] About 5 times the amount of purified water was added to the prune kernels, and the mixture was crushed with a juicer and filtered, or the prune kernels were directly or crushed and then pressed (1). Make milk. To this, add (2) and stir evenly, then add (3) and (4) and mix.

The cosmetics produced according to Examples 2, 3 and 4 of the present invention showed good stability even in an accelerated test at 40 ° C. for 2 months after the production, and caused problems such as separation of components and discoloration. Did not happen.

Although Example 4 does not have the composition of prune kernel extract (Example 1) as in Examples 2 and 3, it suppresses the production of melanin by the action of tyrosinase in the components of prune kernel, Since it is clear that it contains a component that inhibits tyrosinase activity, which has an excellent skin-whitening effect, the use of milk obtained from pruned kernels suppresses the production of melanin, and a tyrosinase-activity inhibitory effect that exhibits a skin-whitening effect. Is obtained.

[0039]

INDUSTRIAL APPLICABILITY According to the present invention, prune kernel can be effectively used, and melanin production due to the action of tyrosinase is significantly suppressed as compared with L-ascorbic acid, and an excellent skin whitening effect is exhibited. It is possible to provide a cosmetic containing a tyrosinase activity inhibitor which is excellent in tyrosinase activity inhibition, good in feeling of use and stability, and safe in handling.

[Brief description of drawings]

FIG. 1 is a graph showing the concentration dependence of tyrosinase activity inhibition of L-ascorbic acid in the prune kernel extract according to Example 1 of the present invention and a control product.

FIG. 2 is a graph showing the concentration dependence of the melanin production inhibitory effect of L-ascorbic acid of the prune kernel extract and the control product according to Example 1 of the present invention.

Claims (6)

[Claims] 1. A tyrosinase activity inhibitor containing as an active ingredient an extract extracted from prune kernels using an extraction solvent. 2. A tyrosinase activity inhibitor containing the extract obtained by immersing a crushed product of prune kernels in an extraction solvent as an active ingredient. 3. The tyrosinase activity inhibitor according to claim 1, wherein the extraction solvent is hot water, water, a hydrophilic organic solvent, or a mixture thereof. 4. A cosmetic comprising the tyrosinase activity inhibitor according to claim 1, 2, or 3. 5. A cosmetic containing milk extracted from prune kernels as an active ingredient. 6. A means for extracting milk from pruned kernels,
The cosmetic according to claim 5, which comprises either filtering a mixture of crushed prune kernel and purified water or pressing the prune kernel directly or after crushing.