JP2007210976A - Tyrosinase activity inhibitor and bleaching cosmetic containing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a safe natural product-originated tyrosinase activity inhibitor which can effectively inhibit the activity of tyrosinase to inhibit the production of melanin of a skin original pigment, and can thus prevent pigmentation, melasma and freckle, and to provide a bleaching cosmetic containing the same. <P>SOLUTION: This tyrosinase activity inhibitor is characterized by containing a water-soluble solvent extract of sweet potato skins, especially a water extract. This bleaching cosmetic is characterized by containing the water-soluble solvent extract (as dried solid content) in an amount of 0.001 to 5 wt.% based on the bleaching cosmetic as the tyrosinase activity inhibitor. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to a tyrosinase activity inhibitor that suppresses the production of melanin in the skin, and a whitening cosmetic that uses this to prevent or prevent pigmentation and stains and freckles after sunburn.

  Pigmentation and spots / sobacus after sunburn generally occur as a result of activation of pigment cells (melanocytes) in the skin due to stimulation by ultraviolet exposure to the skin, hormonal abnormalities or genetic factors, and increased melanin production It is considered a thing. In general, melanin is converted from tyrosine to dopa, from dopa to dopaquinone by the action of the enzyme tyrosinase biosynthesized in pigment cells, and further formed through intermediates such as 5,6-dihydroxyindophenol. ing. Conventionally, the use of a substance that inhibits the activity of tyrosinase to suppress melanin production or a substance that reduces the produced melanin has been studied, and various whitening cosmetics using the same have been proposed. For example, a method using ascorbic acid and a derivative thereof (for example, refer to Patent Documents 1 and 2), a method using arbutin (for example, refer to Patent Document 3), a method using kojic acid and a derivative thereof (for example, refer to Patent Document 4), glutathione Examples thereof include a method to be used (for example, see Patent Document 5), hydroquinone and derivatives thereof (for example, see Patent Document 3), and a whitening cosmetic compounded by combining these (for example, see Patent Documents 7 to 8). However, ascorbic acid and its derivatives are easily oxidized in an aqueous system, are unstable and cause discoloration, and are not preferable because the whitening effect and the product appearance are deteriorated. In addition, it has been pointed out that hydroquinone and its derivatives have problems in use in these whitening cosmetics from the viewpoint of safety such as skin irritation and the possibility of causing an allergic reaction. As a method for improving these, methods for suppressing the production of melanin using ingredients derived from natural products have been studied, but the effect of inhibiting the production of melanin is weak and has not yet been fully effective. No satisfactory product has been obtained.

JP-A 56-120612 JP-A-62-262610 JP-A-5-139950 Japanese Patent Application Laid-Open No. 5-22184 JP-A-8-139946 Japanese Patent Application Laid-Open No. 5-22184 JP-A-8-078364 JP-A-8-103984

  The present invention relates to a safe natural product-derived tyrosinase activity inhibitor capable of suppressing the production of melanin, which is an inherent pigment of skin by effectively suppressing the activity of tyrosinase, and preventing pigmentation, spots and freckles. An object of the present invention is to provide a whitening cosmetic material containing the above.

  As a result of intensive investigations on natural products having a tyrosinase activity inhibitory action and a melanin production inhibitory action that can be used in cosmetics, the present inventors have found that the skin of sweet potato genus plants and extracts thereof have a tyrosinase activity inhibitory action. It has been found that there is an effect of reducing the amount of melanin produced, and the present invention has been completed.

  That is, invention of Claim 1 is a tyrosinase activity inhibitor characterized by including the water-soluble solvent extract of a sweet potato hull.

  The invention of claim 2 is the tyrosinase activity inhibitor according to claim 1, wherein the water-soluble solvent extract of the sweet potato hull extracts the sweet potato at a temperature in the range of 20 ° C. lower than the boiling point of the water-soluble solvent to a boiling point. It is characterized by being obtained.

  Invention of Claim 3 is a tyrosinase activity inhibitor of Claim 1 or 2, Water-soluble solvent is water, C1-C4 water-soluble monohydric alcohol, C1-C6 water-soluble polyhydric alcohol 1 or 2 selected from condensation polymers of water-soluble polyhydric alcohols having 1 to 4 carbon atoms, water-soluble ketones, water-soluble carboxylic acids and carbonates, water-soluble cyclic ethers, pyrrolidone and water-soluble derivatives thereof, and pyridine It is characterized by using more than seeds.

  The invention of claim 4 is the tyrosinase activity inhibitor according to claim 1 or 2, characterized in that the water-soluble solvent is water.

  A fifth aspect of the invention is a whitening cosmetic comprising the tyrosinase activity inhibitor according to any one of the first to fourth aspects.

  Invention of Claim 6 is cosmetics for whitening of Claim 5, and contains 0.001 weight%-5weight% of the water-soluble solvent extract of sweet potato husk as dry solid content with respect to whitening cosmetics whole quantity. It is characterized by.

  The whitening cosmetic composition containing the tyrosinase activity inhibitor containing the solvent extract of the natural sweet potato hull of the present invention can suppress the formation of melanin, which is the original pigment of the skin, and prevent pigmentation and spots and freckles. it can.

  The present invention is a tyrosinase activity inhibitor containing a solvent extract of sweet potato husk and a whitening cosmetic containing the same.

  The sweet potato according to the present invention is a sweet potato belonging to the genus sweet potato (lpomoea). For example, for sweet potatoes, high-grade No. 14, yellow varieties such as Naruto Kintoki, Tamayutaka, Koganesengan, elegant summer, etc .; There are purple varieties such as purple and Ayamurasaki, Kintoki, and red gazebo, and one or more of these can be used.

  The sweet potato portion used in the present invention is a rhizome part of a sweet potato that is a plant (so-called “sweet potato”) and an outer peripheral part of the rhizome part (hereinafter referred to as “sweet potato hull”). The effect of the present invention cannot be sufficiently obtained with a solvent extract other than the rhizome skin. The sweet potato skin may be a small piece, a crushed one, or a dry powder.

  The water-soluble solvent extract of the sweet potato hull of the present invention (hereinafter referred to as “sweet potato extract”) is obtained by extracting sweet potato with a water-soluble solvent under normal pressure or pressure, and further at room temperature or under heating. The obtained solvent extract, diluted solution thereof, concentrated solution thereof, and dried product thereof. Moreover, you may use extraction tools, such as a Soxhlet extractor, in the case of solvent extraction.

  The extraction method of the sweet potato extract in the present invention includes a method of extracting the sweet potato skin by immersing it in a water-soluble solvent at room temperature, a method of extracting the sweet potato skin by immersing it in a heated water-soluble solvent, and a water solution heated under pressure. There is a method of immersing and extracting sweet potato husks in an organic solvent. Among them, a method of immersing and extracting the sweet potato skin in a heated water-soluble solvent is preferable. When the sweet potato skin is immersed and extracted with a heated water-soluble solvent, the heating temperature is a temperature in the range of 20 ° C. lower than the boiling point of the water-soluble solvent to the boiling point, preferably 10 than the boiling point of the water-soluble solvent. The temperature is in the range of low temperature to boiling point. The time required for extraction of sweet potato husks with a water-soluble solvent may be appropriately determined depending on the type of sweet potato, the portion of the sweet potato hull used, the type of water-soluble solvent used, the extraction temperature, the purpose and the degree of extraction of the sweet potato hull. However, 1 to 10 hours is a standard.

  The solvent used in the present invention is a water-soluble solvent for extracting a tyrosinase activity inhibitory substance present in the sweet potato skin, and is water, a C1-C4 water-soluble monohydric alcohol, a C1-C6 water-soluble solvent. 1 type selected from polyhydric alcohols, condensation polymers of water-soluble polyhydric alcohols having 1 to 4 carbon atoms, water-soluble ketones, water-soluble carboxylic acids and carbonates, water-soluble cyclic ethers, pyrrolidone and water-soluble derivatives thereof, and pyridine Alternatively, two or more kinds are used in combination. Specifically, as water, ion-exchanged water, pure water, distilled water; C1-C4 water-soluble monohydric alcohols as methanol, ethanol, propanol, isopropyl alcohol, butanol; C1-C6 water-soluble Examples of the polyhydric alcohol include ethylene glycol, propylene glycol, butylene glycol, glycerin, pentaerythritol, and sorbitol; examples of the condensation polymer of the water-soluble polyhydric alcohol having 1 to 4 carbon atoms include diethylene glycol, triethylene glycol, polyethylene glycol, and propylene. Glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, diglycerin, triglycerin, polyglycerin, ethylene glycol-propylene glycol condensate; As the water-soluble carboxylic acid ester and carbonate ester, methyl acetate, ethyl acetate, γ-butyrolactone, ethylene carbonate, propylene carbonate; as the water-soluble cyclic ether, tetrahydrofuran, dioxane; pyrrolidone and its water-soluble derivatives N-pyrrolidone, N-methylpyrrolidone and N-vinylpyrrolidone. Among these, water, methanol, ethanol, acetone, and tetrahydrofuran are preferable, and water and ethanol are more preferable.

  Specifically, the case where hot water extraction of the sweet potato skin is described as an example. After the sweet potato skin is minced finely and lightly blotted with paper, 10 g of the sweet potato skin and 50 g of purified water are put into a 1000 mL Erlenmeyer flask and boiled. It puts in a water bath, hold | maintains for 1 hour, stirring gently with a stirrer, After cooling, a sweet potato hull is filtered by a filter paper, The hot water extract of a sweet potato hull is obtained. The time for extracting the sweet potato skin with hot water may be appropriately determined in consideration of the target amount of the extract, and is usually 1 hour to 3 hours. In addition, when extracting the sweet potato skin with a water-soluble organic solvent such as ethanol, chop the sweet potato skin finely, lightly blot the water with paper, and then put 10 g of the sweet potato skin and 50 g of ethanol in a 500 mL Erlenmeyer flask at room temperature. Hold for 1 to 3 hours with stirring at room temperature, cool and filter the sweet potato skin with filter paper to obtain a water-soluble organic solvent extract of the sweet potato skin. In the method in which sweet potato skin is immersed in a water-soluble solvent and extracted by pressurizing and heating, the degree of pressurization and the pressurization time are not particularly limited, and can be appropriately determined in consideration of the target extract amount. Usually, a pressurization time of 20 minutes to 1 hour under a pressure of 1.1 atm to 10 atm is a standard.

  The obtained water-soluble organic solvent extract of sweet potato husk may be used as it is or diluted with water, but it is usually concentrated and prepared as a solid or paste or freeze-dried powder. Used. Alternatively, the sweet potato extract obtained as a solid, paste, or powder can be redissolved in water and used as a sweet potato extract aqueous solution. In addition, since the water-soluble organic solvent extract of sweet potato contains various impurities, it is preferable to remove these using means such as filtration. Further, if necessary, it may be used after performing a treatment such as deodorization and decolorization by a known method.

  In general, abnormal production of melanin is suppressed by suppressing tyrosinase activity. The measuring method of the tyrosinase activity inhibitory effect is not specifically limited, The method generally used can be used. For example, mouse B16 melanoma cells (for example, RIKEN, RCB1283) are used after culturing, and after adding a sweet potato peel extract and stirring well, the mixture is incubated at 37 ° C. in the dark for 3 hours, and the supernatant is taken at 405 nm absorbance. There is a method of measuring and measuring the change in absorbance. When sweet potato extract is added to suppress tyrosinase activity, the 405 nm absorbance of the supernatant of the mouse B16 melanoma cell culture becomes low.

  The sweet potato husk extract suppresses the activity of tyrosinase, suppresses the production of dopaquinone by oxidation of L-dopa (3,4-dihydroxyphenylalanine), promotes the production of dopachrome and indolequinone, and further suppresses the production of melanin. Have an effect. The tyrosinase activity inhibitor of the present invention is a tyrosinase activity inhibitor containing a sweet potato peel extract, and may be used in combination with other conventionally used substances having an inhibitory action on tyrosinase activity.

  The whitening cosmetic of the present invention (hereinafter referred to as “whitening cosmetic”) is a whitening cosmetic containing a tyrosinase activity inhibitor containing the above-mentioned sweet potato extract having a tyrosinase activity inhibitory action, and is applied to the skin. By doing so, it is a cosmetic that can suppress the formation of melanin, which is the original pigment of the skin, and can prevent pigmentation and spots and freckles. Specific examples of whitening cosmetics include whitening emulsion, whitening lotion, whitening gel lotion, whitening foundation, whitening cream, whitening pack and the like.

  The form of the whitening cosmetic when the tyrosinase activity inhibitor is blended is not particularly limited, and may be blended in any form such as an aqueous solution, an emulsified solution, a paste, a gel, a solid, or a powder. Can do. The amount of the tyrosinase activity inhibitor containing the sweet potato extract in the whitening cosmetic is determined in consideration of the target tyrosinase activity inhibitory action, and is not uniformly determined. The dry solid content of the sweet potato extract is 0.001 to 5% by weight, preferably 0.01 to 1% by weight, more preferably 0.05 to 0.5% by weight, based on the total amount of the cosmetic for cosmetics.

  The whitening cosmetic preparation is not particularly limited, and can be prepared in the same manner as general cosmetics. The preparation of a whitening emulsion mainly comprising an oily agent as an emulsified component, a polysaccharide acting as an emulsifier, and water will be described as an example. A polysaccharide that acts as an emulsifier [e.g., "Arcasilan" (manufactured by Hakuto Co., Ltd.)] is dispersed in water at room temperature using a disperser, to which sweet potato extract, glycerin, 1,3-butylene glycol and 1, 2-Pentanediol and the like are mixed to prepare an aqueous dispersion containing an emulsifier as a uniform. A uniform emulsified component is prepared by warming and stirring an oily agent of an emulsified component of a whitening emulsion such as squalane, olive oil, oil-soluble natural vitamin, stearyl alcohol and the like. The aqueous dispersion containing the emulsifier is heated to a predetermined temperature, and the emulsified component is gradually added and emulsified while stirring at 8000 rpm with a homogenizer (or homomixer). Further, the emulsion is matured by stirring and then cooled by stirring to obtain the whitening emulsion of the present invention. In addition, a whitening lotion (skin lotion) consisting only of an aqueous phase component simply adds a tyrosinase activity inhibitor to the aqueous phase as it is and dissolves it.

The whitening cosmetic composition of the present invention includes useful ingredients used in preparations such as drugs, quasi-drugs, and cosmetics within the range that does not impair the effects of the present invention, such as purified water, hot spring water, and deep water. , Moisturizer, astringent, whitening agent, anti-inflammatory (anti-inflammatory) agent, skin (cell) activator, antibacterial agent, transdermal absorption enhancer, refresher, antioxidant, antiseptic, chelating agent, anti-fading agent A buffering agent and the like can be arbitrarily selected and blended.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

[Tyrosinase activity inhibitor of the present invention]
・ Tyrosinase activity inhibitor (A-1)
“Ayamurasaki” was peeled off, 10 g of sun-dried skin was immersed in 50 g of hot water (pure water) at 90 ° C. for 1 hour, allowed to cool, and then filtered through No. 2 filter paper. The filtrate was concentrated with an evaporator and dried to obtain about 20 mg (as a solid content) of a sweet potato hull extract (“Ayamurasaki” hull extract). This was designated as a tyrosinase activity inhibitor (A-1).
・ Tyrosinase activity inhibitor (A-2)
About 20 mg (as a solid content) of “red bean” hull extract was obtained using “red bean” hull in the same manner as the tyrosinase activity inhibitor (A-1). This was designated as tyrosinase activity inhibitor (A-2).
・ Tyrosinase activity inhibitor (A-3)
About 20 mg (as solid content) of “Kinki” hull extract (A-3) was obtained using “Kinki” hull in the same manner as the tyrosinase activity inhibitor (A-1). This was designated as a tyrosinase activity inhibitor (A-3).
・ Tyrosinase activity inhibitor (A-4)
About 20 mg (as solid content) of “red satsuma” hull extract was obtained using “red satsuma” hull in the same manner as the tyrosinase activity inhibitor (A-1). This was designated as tyrosinase activity inhibitor (A-4).
・ Tyrosinase activity inhibitor (A-5)
The portion after peeling the skin of “Kinki” was dried and extracted with hot water in the same manner as the sweet potato shell extract (A-1). As) got. This was designated as a tyrosinase activity inhibitor (A-5).

[Comparative Tyrosinase Activity Inhibitor]
Tyrosinase activity inhibitor (B-1): L-ascorbic acid phosphate Na (manufactured by Showa Denko KK)
Tyrosinase activity inhibitor (B-2): L-ascorbic acid (manufactured by Takeda Pharmaceutical Company Limited)
・ Tyrosinase activity inhibitor (B-3): Grabrizine (manufactured by Maruzen Pharmaceutical Co., Ltd.)
-Tyrosinase activity inhibitor (B-4): Astaxanthin (reagent, manufactured by Sigma)

(Other ingredients)
C-1: 1,3-butylene glycol (reagent, Kanto Chemical Co., Inc.)
C-2: Glycerin (reagent, Kanto Chemical Co., Inc.)
C-3: Paraoxybenzoic acid ester (reagent, Kanto Chemical)

[Tyrosinase activity inhibition test 1]
Inhibition of tyrosinase activity of sweet potato skin extract using mouse B16 melanoma cells (RIKEN, RCB1283) cultured in a conventional method (37 ° C., 5 wt% CO ₂ ) using DMEM medium containing 10 wt% fetal bovine serum (FBS) A test was conducted. In the tyrosinase activity inhibition test, the tyrosinase activity inhibitor (A-1) containing the sweet potato husk extract was dissolved in water and used as an aqueous solution of tyrosinase activity inhibitor (A-1) having a solid content of sweet potato husk extract of 400 ppm.

Cells grown to almost the entire bottom of the culture flask are released by normal trypsinization, washed with phosphate buffered saline (PBS), suspended in PBS to 5 × 10 ⁶ cells / mL, and the cells A suspension was obtained. Cell suspension 0.2 mL (1 × 10 ⁶ cells) 0.33% wt-Triton X-100 aqueous solution 0.2 mL, 0.1 wt% L-DOPA aqueous solution 0.2 mL and 400 ppm concentration tyrosinase activity inhibition After sequentially adding 0.2 mL of the aqueous solution of the agent (A-1) and stirring sufficiently, a test solution was prepared, followed by incubation at 37 ° C. in the dark for 3 hours. Next, the mixture was homogenized by ultrasonic treatment (centrifuged if necessary), and the supernatant was taken and the absorbance at 405 nm was measured. The tyrosinase activity inhibitory action is calculated as the tyrosinase activity inhibition rate (%) by the following formula, and the higher this value, the more preferable.
Tyrosinase activity inhibition rate (%) = [(β−α) / β] × 100
α: Absorbance when tyrosinase activity inhibitor is added β: Absorbance when tyrosinase activity inhibitor is not added In addition, the melanin production inhibitory action is calculated from the melanin amount in the supernatant from a calibration curve using a melanin standard product. The production inhibition rate (%) was evaluated. Higher values are preferable.
Melanin production inhibition rate (%) = (γ / ε) × 100
γ: melanin amount when tyrosinase activity inhibitor is added ε: melanin amount when no tyrosinase activity inhibitor is added If the tyrosinase activity inhibitor (A-1) of the sweet potato peel extract has a melanin production inhibitory activity, the absorbance at 405 nm is The tyrosinase activity inhibition rate (%) and the melanin production inhibition rate (%) are increased. The addition amount of the tyrosinase activity inhibitor (A-1) was changed, and the absorbance at 405 nm was measured for each. Similarly, tyrosinase activity inhibitory action and melanin production inhibitory action were evaluated using tyrosinase activity inhibitors (A-2) to (A-5) instead of tyrosinase activity inhibitor (A-1). The results are shown in Tables 1 to 3. In the table, “ppm of active ingredient vs. total amount” indicates the ratio of the active ingredient of the tyrosinase activity inhibitor to the amount of the test solution (corresponding to “total amount”). In the tyrosinase activity inhibitor containing the sweet potato peel extract, The ratio with respect to the amount of test liquid solid content (equivalent to “total amount”) of the skin extract is shown.

本発明のサツマイモ外皮抽出物は、表２で示されるようにヒトメラノサイト細胞のチロシナーゼ活性を抑制することが認められ、表３ではサツマイモ外皮抽出物は、ヒトメラノサイト細胞のメラニン生成を減少させることが認められた。

As shown in Table 2, the sweet potato husk extract of the present invention was found to suppress the tyrosinase activity of human melanocyte cells, and in Table 3, the sweet potato husk extract can reduce melanin production of human melanocyte cells. Admitted.

[Erythema suppression and pigmentation suppression test]
Erythema Suppression Test Colored guinea pigs (10 per group) were shaved at the four backs and washed well with warm water, and the four were divided into two, one for the test group and the other for the control group. 0.2 ml of the whitening composition for external preparation prepared with the composition shown in Table 4 was applied to each of two locations in the test area, and irradiated with ultraviolet rays under anesthesia 24 hours later. For ultraviolet irradiation, three FL20S / BLB lamps and three FL20S / E30 lamps manufactured by Toshiba Corporation were used at the same time, and irradiation was performed with an ultraviolet ray amount of 4.8 × 10 ⁶ erg / cm ² . Immediately after the ultraviolet irradiation, 0.2 ml of the whitening composition was applied again to the portion where the whitening composition was previously applied. Further, 0.2 ml of the composition for whitening was applied 12 hours and 24 hours after UV irradiation. After 24 hours of irradiation, the degree of erythema in the shaved portion of the guinea pig was visually evaluated, and after 7 days, the degree of pigmentation was visually evaluated, and each guinea pig was scored to determine the average value of each group. Evaluation of the degree of erythema and pigmentation was as follows. The results are shown in Table 4.

(Evaluation criteria for erythema suppression effect)
<Evaluation><Content and Evaluation>
6 points: No erythema is observed.
4 points: Very slight erythema is observed.
2 points: Erythema is observed, but the boundary with the non-irradiated site is unclear.
0 point: Erythema is observed, and the boundary with the non-irradiated site is clear.

(Evaluation criteria for pigmentation inhibitory effect)
<Evaluation><Contents>
6 points: No pigmentation is observed.
4 points: Very little pigmentation is observed.
2 points: Pigmentation is observed, but the boundary with the non-irradiated site is unclear.
0 point: Pigmentation is observed, and the boundary with the non-irradiated site is clear.

本発明のサツマイモ外皮抽出物を添加した美白用外用剤組成物は、各種美白剤単独に比較して、紫外線による紅斑や色素沈着を効果的に抑制することが示された。

It was shown that the whitening external preparation composition to which the sweet potato peel extract of the present invention is added effectively suppresses erythema and pigmentation due to ultraviolet rays as compared with various whitening agents alone.

[Evaluation of skin external preparation for whitening]
According to the following prescription, cosmetics, milky lotions, creams 1 to 4 and packs were prepared and continuously used for 40 months for 40 people, “Test 1: Improvement of dullness, spots and freckles”, “ Tests were conducted on “Test 2: Improvement of makeup paste” and “Test 3: Improvement of rough skin”. The usage of cosmetics was not restricted, and was the same as that of normal cosmetics. The results of use were tabulated by self-report. The evaluation criteria for each test were as follows.
・ Evaluation criteria for “Test 1: Improvement of dullness, spots and freckles” ○: The number of respondents who improved dullness, spots and freckles was 21 or more out of 40.
×: The number of respondents who improved dullness, blotches and freckles was 20 or less out of 40.
・ Evaluation criteria for “Test 2: Improvement of makeup paste” ○: 21 or more respondents out of 40 responded that makeup paste was improved.
X: The number of respondents is less than 20 out of 40 when makeup paste is improved.
Evaluation criteria for “Test 3: Improvement of rough skin” ○: The number of respondents who improved rough skin was 21 or more out of 40.
X: The number of respondents who improved rough skin was 20 or less out of 40.
The results are shown in Table 10.

(Example 13: Lotion 1)
The composition of the skin lotion 1 is shown in Table 5.

１．区分ｂの多糖類（アルカシーラン）を室温にて予めディスパーザを用いて水に前分散させた（分散液１）。
２．区分ａの各成分を計量し、均一混合溶解した（分散液２）。
３．分散液２に分散液１を加えた後、１０分間攪拌を行って化粧水１（実施例５）を得た。

1. The polysaccharide of category b (alkathylan) was predispersed in water at room temperature using a disperser (dispersion 1).
2. Each component of section a was weighed and uniformly mixed and dissolved (dispersion 2).
3. After adding Dispersion 1 to Dispersion 2, the mixture was stirred for 10 minutes to obtain skin lotion 1 (Example 5).

(Example 14: Lotion 2)
A lotion 2 (Example 14) was obtained by replacing the sweet potato peel extract (A-1) of component a in Example 13 with the same amount of the sweet potato peel extract (A-2).

(Example 15: lotion 3)
A lotion 3 (Example 15) was obtained by replacing the sweet potato peel extract (A-1) of component a in Example 13 with the same amount of the sweet potato peel extract (A-3).

(Example 16: Lotion 4)
A lotion 4 (Example 16) was obtained by replacing the sweet potato peel extract (A-1) of component a in Example 13 with the same amount of the sweet potato peel extract (A-4).

(Comparative Example 9: Lotion 5)
A lotion 5 (Comparative Example 9) was obtained by substituting the same amount of purified water for the sweet potato peel extract (A-1) of component a in Example 13.

(Example 17: Latex 1)
The composition of emulsion 1 is shown in Table 6.

１，区分ｃの多糖類（アルカシーラン）を室温にて予めディスパーザを用いて水に前分散させた（分散液１）。
２．区分ａの各成分を計量し、均一混合加温溶解した（分散液２）。
３．区分ｂの各成分を計量し、７０℃に加温し溶解した（分散液３）。
４．７０℃に加温したまま、分散液１に分散液２を加え、ホモジナイザー（あるいはホモミキサー）で８０００ｒｐｍに攪拌しながら、分散液３を徐々に添加した。
５．添加後１０分間攪拌を行い、室温まで冷却して乳液１（実施例１７）を得た。

The polysaccharide of category 1, c (alkathylan) was predispersed in water in advance using a disperser at room temperature (dispersion 1).
2. Each component of section a was weighed, uniformly mixed and dissolved by heating (dispersion 2).
3. Each component of section b was weighed and heated to 70 ° C. to dissolve (dispersion 3).
While being heated to 4.70 ° C., dispersion 2 was added to dispersion 1, and dispersion 3 was gradually added while stirring at 8000 rpm with a homogenizer (or homomixer).
5). After the addition, the mixture was stirred for 10 minutes and cooled to room temperature to obtain an emulsion 1 (Example 17).

(Comparative Example 10: Emulsion 2)
An emulsion 2 (Comparative Example 10) was obtained by replacing with the sweet potato skin extract (A-2) of component a in Example 17 with the same amount of purified water.

(Example 18: Cream 1)
The composition of Cream 1 is shown in Table 7.

１．区分ｂの多糖類（アルカシーラン）を室温にて予めディスパーザを用いて水に前分散させた（分散液１）。
２．区分ａの各成分と分散液１を均一に混合、加温溶解した（分散液２）。
３．区分ｃの各成分を計量して加温溶解した（分散液３）。
４．分散液２をホモジナイザー（あるいはホモミキサー）で８０００ｒｐｍに攪拌しながら、分散液３を徐々に添加した。
５．添加後１０分間攪拌を行った（分散液４）。
６．区分ｄのハイビスワコー１０４、１０５を予めティスパーザを用いて水に分散させた（分散液５）。
７．区分ｅの各成分を均一に分散させた（分散液６）。
８．分散液５に分散液６を加えて、均一混合した（分散液７）。
９．分散液４に分散液７を加えて中和後、室温まで冷却し、クリーム１（実施例１８）を得た。

1. The polysaccharide of category b (alkathylan) was predispersed in water at room temperature using a disperser (dispersion 1).
2. Each component of section a and dispersion 1 were uniformly mixed and dissolved by heating (dispersion 2).
3. Each component of section c was weighed and dissolved by heating (dispersion 3).
4). While the dispersion 2 was stirred at 8000 rpm with a homogenizer (or homomixer), the dispersion 3 was gradually added.
5). Stirring was performed for 10 minutes after the addition (dispersion 4).
6). Hibiswako 104 and 105 of section d were previously dispersed in water using a tissparzer (dispersion 5).
7). Each component of section e was uniformly dispersed (dispersion 6).
8). Dispersion 6 was added to dispersion 5 and mixed uniformly (dispersion 7).
9. Dispersion 7 was added to dispersion 4, neutralized, and then cooled to room temperature to obtain cream 1 (Example 18).

(Comparative Example 11: Cream 2)
Instead of the sweet potato extract skin (A-2) of component 18 in Example 18, the same amount of purified water was used to prepare Cream 2 (Comparative Example 11).

(Example 19: Pack 1)
The composition of pack 1 is shown in Table 8.

１．区分ｃの多糖類（アルカシーラン）を室温にて予めディスパーザを用いて水に前分散させた（分散液１）。
２．区分ａの各成分を計量し、均一混合加温溶解した（分散液２）。
３．分散液１をホモジナイザー（あるいはホモミキサー）で８０００ｒｐｍに攪拌しながら、分散液２を徐々に添加した。
４．添加後１０分間攪拌を行った後、室温まで冷却し、区分ｂを添加、更に１０分間攪拌を行ってパック１（実施例１９）を得た。

1. The polysaccharide of category c (Alcacilan) was predispersed in water at room temperature using a disperser (dispersion 1).
2. Each component of section a was weighed, uniformly mixed and dissolved by heating (dispersion 2).
3. While the dispersion 1 was stirred at 8000 rpm with a homogenizer (or homomixer), the dispersion 2 was gradually added.
4). After the addition, the mixture was stirred for 10 minutes, and then cooled to room temperature, added with section b, and further stirred for 10 minutes to obtain pack 1 (Example 19).

(Comparative Example 12: Pack 2)
A pack 2 (Comparative Example 12) was obtained by replacing with the sweet potato peel extract (A-2) of component b of Example 19 with the same amount of purified water.

(Example 20: Liquid foundation 1)
The composition of Liquid Foundation 1 is shown in Table 9.

１．区分cのメチルセルロースを室温にて予めディスパーザを用いて水に前分散させた（分散液１）。
２．区分ａの各成分を計量し、均一混合加温溶解した（分散液２）。
３．区分ｂの各成分を計量し、加温溶解した（分散液３）。
４．分散液１に分散液２を加温下にて加え、ホモジナイザー（あるいはホモミキサー）で８０００ｒｐｍに攪拌しながら、分散液３を徐々に添加した。
５．添加後１０分間攪拌を行い、室温まで冷却してリキッドファンデーション１（実施例２０）を得た。

1. The methyl cellulose of section c was predispersed in water at room temperature using a disperser (dispersion 1).
2. Each component of section a was weighed, uniformly mixed and dissolved by heating (dispersion 2).
3. Each component of section b was weighed and dissolved by heating (dispersion 3).
4). Dispersion 2 was added to dispersion 1 under heating, and dispersion 3 was gradually added while stirring at 8000 rpm with a homogenizer (or homomixer).
5). After the addition, the mixture was stirred for 10 minutes and cooled to room temperature to obtain Liquid Foundation 1 (Example 20).

(Comparative Example 13: Liquid Foundation 2)
A liquid foundation 2 (Comparative Example 13) was obtained by substituting the same amount of purified water for the sweet potato peel extract (A-2) of component a in Example 12.

本発明の美白用化粧料である化粧水１〜４、乳液１、クリーム１、パック１、リキッドファンデーション１は、本発明のサツマイモ外皮抽出物を含まない美白用化粧料の化粧水５、乳液２、クリーム２、パック２、リキッドファンデーション２に比較して、くすみ、しみ、そばかすの改善効果、「化粧ののり」の改善、肌荒れの改善が得られることが分かる。

Skin lotion 1 to 4, skin lotion 1, cream 1, pack 1 and liquid foundation 1 which are the skin whitening cosmetics of the present invention are skin whitening cosmetic skin lotion 5 and milk 2 that do not contain the sweet potato skin extract of the present invention. Compared with Cream 2, Pack 2 and Liquid Foundation 2, it can be seen that the effect of improving dullness, blotting and freckles, the improvement of “cosmetic paste”, and the improvement of rough skin can be obtained.

Claims (6)

  A tyrosinase activity inhibitor comprising a water-soluble solvent extract of sweet potato hulls.   The tyrosinase activity inhibitor according to claim 1, wherein the water-soluble solvent extract of sweet potato hulls is obtained by extracting sweet potato at a temperature in the range of 20 ° C lower than the boiling point of the water-soluble solvent to a boiling point.   The water-soluble solvent is water, a C1-C4 water-soluble monohydric alcohol, a C1-C6 water-soluble polyhydric alcohol, a C1-C4 water-soluble polyhydric alcohol condensation polymer, a water-soluble ketone. The tyrosinase activity inhibitor of Claim 1 or 2 using 1 type, or 2 or more types chosen from water-soluble carboxylic acid and carbonate ester, water-soluble cyclic ether, pyrrolidone and its water-soluble derivative, and a pyridine.   The tyrosinase activity inhibitor according to claim 1 or 2, wherein the water-soluble solvent is water.   A whitening cosmetic comprising the tyrosinase activity inhibitor according to any one of claims 1 to 4. The whitening cosmetic composition according to claim 5, comprising a water-soluble solvent extract of sweet potato skin as a dry solid content in an amount of 0.001% to 5% by weight based on the total amount of the whitening cosmetic composition.