WO2005067885A1

WO2005067885A1 - Skin whitening composition having synergic whitening effect

Info

Publication number: WO2005067885A1
Application number: PCT/KR2005/000146
Authority: WO
Inventors: Chang Hoon Park; Byung Young Kang; Han Kon Kim; Sang Hoon Han; Jae Sung Hwang
Original assignee: Amorepacific Corporation
Priority date: 2004-01-15
Filing date: 2005-01-14
Publication date: 2005-07-28
Also published as: KR101072133B1; JP2007517866A; KR20050075115A; CN1909885A; JP4660487B2; CN100459970C

Abstract

The present invention relates to a skin-whitening cosmetic composition, that prevents melanin hypersynthesis and promotes exhaustion of systhesized melanin from the skin. More particularily, the skin-whitening cosmetic composition of the prevent invention comprises licorice extract with red ginseng extract, white birch extract and papain, and thus has an excellent skin-whitening effect by improving that of the licorice extract, which is the whitening component.

Description

[DESCRIPTION] [Invention Title]

SKIN; WHITENING COMPOSITION HAVING SYNERGIC WHITENING EFFECT

[Technical Field]

The present invention relates to a skin-whitening cosmetic composition, that prevents melanin hypersynthesis and promotes exhaustion of synthesized melanin from the skin. More particularly, the skin-whitening cosmetic composition of the prevent invention comprises licorice extract with red ginseng extract, white birch extract and papain, and thus has an excellent skin-whitening effect by improving that of the licorice extract, which is the whitening component.

[Background Art] When human skin is exposed to UV light, melanin determining the color of the

human skin is synthesized and released, inducing hyperpigmentation such as melasma,

freckles and spots, which are unfavorable results with regard to beauty.

The process of the melanin synthesis is as follows: tyrosinase in cells acts on tyrosine

to form dopaquinone, and melanin is produced therefrom. Therefore, in order to prevent skin

darkness, an approach to inhibit a part of the process of the melanin synthesis in order to

reduce the melanin synthesis itself has been generally studied. Examples of such whitening

agents developed are kojic acid, arbutine, licorice extract, vitamin A and vitamin C.

However, melanin plays important roles, in addition to that of determining skin color, such as protecting a gene from UN light by forming a hat-like structure around a nucleus, and protecting protein in the cell by eliminating free radicals. As a result, it is possible to excessively inhibit the melanin synthesis itself, which thereby cannot accomplish its minimum required role in the skin. Therefore, methods for brightening a skin- tone by rapidly eliminating hypersynthesized melanin selectively are desirable.

[Disclosure] [Technical Problem] To resolve the problems, the present inventors have studied three aspects in order to

improve a skin whitening effect in connection with skin structure.

As a result, the present inventors found that the skin-whitening effect is promoted by

maximizing a skin turnover mechanism which uses ® papain in order to improve separation

of the outermost cell of the keratin layer; (D red ginseng extract in order to stimulate cell

growth; and (H) white birch extract in order to malce a rough skin soft, and thereby completed

the present invention.

Thus, an object of the invention is to provide a method for maximizing the skin

whitening effect of a whitening component. To attain this object of the present invention, a

cosmetic composition containing red ginseng extract, white birch extract and papain, is

provided.

Another object of the present invention is to provide a skin-whitening cosmetic composition that contains a licorice extract as a whitening agent with red ginseng extract, white birch extract and papain.

[Best Mode]

The present invention provides a skin-whitening cosmetic composition that contains

licorice extract, red ginseng extract, white birch extract and papain.

The composition according to the present invention promotes the skin-whitening

effect in consequence of inhibiting melanin hypersynthesis and promoting the exhaustion of

the hypersynthesized melanin. Further, the composition rapidly processes the skin turnover

cycle by promoting cell exfoliation, cell formation and skin softness. The present inventors found that a skin-whitening effect of the composition rises

unexpectedly when the composition contains a mixture of licorice extract, red ginseng extract,

white birch extract and papain, compared with those of the individual components when alone.

Namely, when the composition comprises the components by mixing, it may have a

maximized skin-whitening effect. The skin-whitening composition containing licorice

extract, red ginseng extract, white birch extract and papain is hereafter referred to as " Wliite

Energy Complex" .

Said licorice extract used in the present invention is the major component for

inhibiting melanin formation. The amount of licorice extract is preferably 0.001 ~2.0 wt% of

the total weight of the composition. If it is less than 0.001% by weight, the skin- whitening

effect cannot be obtained, and if it exceeds 2.0% by weight, it may induce skin irritation.

Papain mainly plays a role in promoting the skin cell exfoliation. The amount of

papain is preferably 0.01 —0.1 wt% of the total weight of the composition. If it is less than 0.01% by weight, the skin- whitening effect cannot be obtained, and if it exceeds 0.1% by

weight, it may induce skin irritation.

Red ginseng extract mainly plays a role in stimulating cell growth. It is preferably 6

year-old red ginseng extract from the aspects of cost and efficiency. The amount of red

ginseng extract is preferably 0.01 —5.0 wt%. If it is less than 0.01% by weight, the

skin- whitening effect cannot be obtained, and if it exceeds 5.0% by weight, the cost of the

product increases.

White birch extract contributes skin softness. The amount of white birch extract is

preferably 0.01 —5.0 wt% of the total weight of the composition. If it is less than 0.01% by

weight, the skin- whitening effect cannot be obtained, and if it exceeds 5.0% by weight, it may

induce skin irritation.

The effects of said components show a synergic effect, as well as the above described

effects, by the mixing thereof.

Besides, the present invention may use kojic acid, arbutine, vitamin A or vitamin C

instead of licorice extract as the major components of skin- hitening activity.

Hereinafter, the present invention is described in more detail.

Skin- whitening agents developed until the present date inhibit the activity of

tyrosinase, which plays the most important role in melanin synthesis, and thereby reduce the

quantity of melanin. However, such skin-whitening agents have a problem that their usage

amount is limited because of the side effect of inducing skin irritation. Therefore, the

composition of the present invention is produced to use the system for promoting skin turnover activity in order to promote the skin-whitening effect of presently developed

skin-whitening agents, thereby providing an excellent skin- whitening effect.

Skin is composed of the epidermis, which is a shallow layer, and the dermis, which is a deeper layer under the epidennis. Under the dermis is a distinct connective tissue layer(hypodermic tissue), known as "subcutaneous tissue". The epidermis is an outer layer of the skin composed of epithelial tissue, and consists of five layers. Specifically, from the inside the epidennis consists of a basal layer, a spinous layer, a granular layer, a clear layer and a homy layer; it forms a new cell in the bottom and then continuously thrusts up the new cell outwards to be gradually disjoined as a keratinized death cell. The cycle described above, in which a new cell synthesized in the bottom thrusts up an old cell to the outside of the body to be disjoined therefrom, is called "turnover". The composition of the present invention rapidly exhausts melanin formed in the epidermis to the outside of the body by promoting this turnover.

[Mode for Invention]

The present invention will be described in more detail by way of the following Examples, Comparative Examples and Experimental Examples. However, these examples are provided for the purpose of illustration only and should not be construed as limiting the scope of the invention, which will be apparent to one skilled in the art.

<Examples 1 and 2> Preparation of the skin-whitening composition (White Energy

Complex 1 and 2)

Licorice extract was purchased as "Polyol soluble licorice ext P-T(40)", containing more than 35% of glabridin, produced by Maruzen Pharmaceuticals Co. Ltd(Japan).

Red ginseng extract was prepared by following a process for enzymolysis of 6

year-old red ginseng .extract produced by Bioland (Korea).

« Process for Enzymolysis » lOg of red ginseng extract were dissolved in lOOm-C. of citrate buffer(pH 5.5), lg of

naringinase from Penicilliwn sp. was added, and then the mixture was stirred in a water bath

at 40 ^°C for 48hrs. When the substance had disappeared and periodically confiπned by thin

layer chromatography, the mixture was hydrothermally heated for 10 min. to terminate the

reaction, then extracted and concentrated three times by equal ether. Products were analyzed

using silica gel column chromatography(chloroform:methanol = 9:1) to obtain red ginseng

extract(10.5% yield).

White birch extract was purchased as "white birch extract" produced by Arch

Personal Care Products(U.S.A.).

Papain was purchased as "Refined papain powder" produced by CPC Wolfgang

Muhlbauer GmbH(Germany).

Licorice extract, red ginseng extract, white birch extract and papain were mixed in a

ratio of 5:5:10:0.3 to prepare 203 g of the skin- whitening composition 1 (White Energy

Complex 1: Example 1).

In addition, licorice extract, red ginseng extract, white birch extract and papain were

mixed in a ratio of 5:10:20:0.6 to prepare 356g of the skin-whitening composition 2(White

Energy Complex 2: Example 2). Experimental Example 1> Determination of the effect of inhibiting the melanin formation

HM3KO cells(Y. Funasaka, Department of Dermatology, Kobe University School of

Medicine, 5-1 Kusunoki-cho 7-chrome, Chuo-ku, Kobe 650, Japan), which are the human

melanoma cells, were placed in Minimum Essential Medium (MEM) containing 10% of

bovine embryo serum and cultured at 37 ^°C, 5% CO₂. Cultured cells were spread on the

bottoms of 75-well flasks with a cell number of 3x10⁵ per well, and left overnight so that the

cells were stuck on the wall. After this was confirmed each medium was changed to a new

one containing lOppm of the test samples. The test samples used are described in Table 1 below.

For the control group, a medium containing DMSO was used. To compare the effect of each component, it was accompanied by using the

components alone, i.e. as licorice extract, kojic acid, arbutine, vitamin A, vitamin C, red

ginseng extract, white birch extract and papain, and by using the mixtures formed through

mixing a number of these components cases in combinations.

In the above way, each medium was changed to a new one containing test samples once every 2 days, until enough cells were cultured to fill the flask. The culture fluid was then removed, washed with PBS, and dissolved in IN NaOH to measure optical density(OD) at 500nm, and the rate of inhibiting the melanin formation was calculated in the following Numerical Formula 1. The results are shown in Table 1.

[Numerical Formula 1 ]

Rate of inhibiting melanin formation(%) = {l-(OD of each test sample/OD of the control)}X100 [Table 1 ]

As can be seen in the result of Table 1, it was confirmed that said papain, red ginseng

extract and white birch extract, which composed the White Energy Complex, had a low rate

of inhibiting the melanin formation in the case of using separately, while having a higher

skin-whitening effect in the case of being used as a combination with one or two of the said

components together with licorice extract, and showed the highest of the skin-whitening

effects in the case of being used by mixing said three components. In addition, when kojic acid, arbutine, vitamin A and vitamin C, which are

well-known as skin-whitening agents, were used in combination with papain, red ginseng

extract and white birch extract, it was confirmed that the skin-whitening effect of the

composition increased.

Experimental Example 2> Skin-whitening effect on human skin An opaque tape having 6 holes of diameter 1.5cm was adhered to an upper-ann of

each of ten(lθ) healthy men, and a UN beam(UNB) having a strength 1.5 —2 times the

Minimal Erythema Dose of each subject was radiated to induce melanization of the skin. The

test samples were then applied, and after two(2) months the darkness of the skin was

determined using chiOmameter.

Test samples were prepared according to the compositions in Table 2, and the

Formulations of the Examples and the Comparative Formulations according to Table 2 were

applied 2 times a day(in the morning and the evening).

< Fonnulations 1 —5 and Comparative Formulations 1 — 4 >

The fonnulations are O/W lotion and the unit is wt%. The viscosities of the prepared

fonnulations were 7000-1 lOOOcp, which were measured the next day after each fomiulation

was put in an isothermal bath at 30 ^°C, and the pH(10% solution basis) was 6.5 — 7.5. « Preparation Method »

(1) Oily ingredient 1 was unifonnly mixed by heating at 70—75 ^°C .

(2) Aqueous ingredient 1 was dissolved and unifonnly mixed by heating at 70 — 5 ^°C.

(3) Said (2) of the aqueous mixture was stirred at 70 ~ 75 ^°C, adding said (1) of the oily mixture to prepare emulsion, then continuously adding the oily ingredient 2 and the aqueous ingredient 2, and cooling the resulting mixture to 28 ~ 30 ^°C .

[Table 2]

The effect was judged by use of the value "L" showing the lightness of the skin (The

value "L" of the Korean people with no sun-bum is usually 50-70). If there is any effect

caused by application of the test sample, the value L increases. The comparison was made

between the test samples by the value Δ L(the final value of L - the value of L before the

application of the test sample). The larger is the value Δ L, the greater is the skin- whitening

effect. The values Δ L are shown in Table 3 below.

[Table 3]

As the result of Table 3, it was confirmed that the value Δ L of Fonnulations 1 — 5,

which comprised licorice extract with at least two selected from the group consisting of

papain, white birch extract and red ginseng extract, were higher than those of Comparative

Fomiulation 1, which comprised only licorice extract, and Comparative Formulations 2—4,

which comprised licorice extract with white birch extract, papain and red ginseng extract

respectively. Especially, the value Δ L of Fonnulations 1 and 2, which comprised the White Energy Complex containing tliree components, were the highest, thus Formulations 1 and 2

showed relatively larger skin- whitening effects than the others.

In addition, it was confirmed that if the amount of the White Energy Complex

increased, than the Fonnulation relatively increased the skin-whitening effect.

As described above, it was confinned that the cosmetic composition of the oil-in-water emulsion prepared by using the White Energy Complex according to the prevent invention improved the skin-whitening effect.

Claims

[CLAIMS] [Claim 1 ]

A composition of skin-whitening supplement for improving the activity of a skin-whitening agent, comprising at least two components selected from the group consisting of red ginseng extract, white birch extract and papain. [Claim 2]

The composition according to Claim 1, wherein said skin- whitening agent is at least one selected from the group consisting of kojic acid, arbutine, licorice extract, vitamin A and vitamin C. [Claim 3]

A skin-whitening cosmetic composition comprising licorice extract as the

skin-whitening component, characterized in further comprising at least two components

selected from the group consisting of red ginseng extract, white birch extract and papain. [Claim 4] The composition according to Claim 3, wherein the amounts of said components are

licorice extract 0.001 —2.0 wt%, papain 0.01 —0.1 wt%, red ginseng extract 0.01 —5.0 wt%

and white birch extract 0.01 — 5.0 wt% of the total weight of the composition.