JPH07121855B2 - Melanin production inhibitor - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a skin melanin production inhibitor.

[0002]

BACKGROUND OF THE INVENTION Although there are many unclear points regarding the mechanism of skin pigmentation, such as spots and freckles, it is generally caused by abnormal melanin metabolism due to skin exposure to ultraviolet rays and abnormal hormone secretion. It is considered that the melanin produced by the increased production of melanin in the epidermis deposits on the skin.

Conventionally, various substances have been applied to reduce or prevent the deposition of melanin on the skin. One of them is hydroquinone, which has a strong bleaching action, but this has a problem in terms of safety such that the bleaching action on the skin is too strong and permanent dye escape may occur.

Kojic acid and arbutin, which have been developed and applied as melanin production inhibitors in recent years, have a problem that they are required to be continuously used for a long period of time because they are highly safe but their effects are moderate. There is a demand for safer and more effective melanin production inhibitors.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a safer and faster-acting novel melanin production inhibitor.

[0006]

That is, the present invention provides formula (I):

[0007]

[Chemical 2]

There is provided a melanin production inhibitor containing aminobenzoic acid represented by: Aminobenzoic acid represented by the formula (I) is a kind of amino acid and has extremely high safety. For example, p-aminobenzoic acid is one of the constituents of folic acid and is known as a growth factor for many microorganisms. o-Aminobenzoic acid, also called anthranilic acid or vitamin L ₁ , has a lactating effect on mammals.

It has long been known that aminobenzoic acid derivatives have an ultraviolet absorbing action (for example, JP-A-2-
157219 and JP-A-60-174710),
Utilizing this action, the stimulus caused by exposure to ultraviolet rays is alleviated, and erythema and pigmentation of the skin are suppressed.

The present inventors have determined that aminobenzoic acid has an effect of suppressing the production of melanin in addition to the above-mentioned action. Aminobenzoic acid inhibits the activity of tyrosinase, which plays a crucial role in melanin production, and is considered to suppress melanin production mainly by this action. However, the involvement of peroxidase, dopachrome tautomerase, etc. in addition to tyrosinase in the production of melanin is known, and the melanin production inhibitor of the present invention may have some function other than the inhibition of tyrosinase activity. There is also.

The melanin production inhibitor of the present invention contains aminobenzoic acid represented by the formula (I). Aminobenzoic acid may have any structure of ortho, meta and para. The amount of aminobenzoic acid added to the melanin production inhibitor varies depending on the dosage form and is not particularly limited. Usually 0.0001 to 30% by weight, preferably 0.0001 to
Add 10% by weight. Aminobenzoic acid is 0.00001
If it is less than wt%, the melanin production inhibitory effect cannot be sufficiently obtained. When the amount of aminobenzoic acid added exceeds 30% by weight, the solubility is reduced and no further increase in the effect of suppressing melanin production is observed, which is not preferable.

The melanin production inhibitor of the present invention is useful as a skin whitening agent which prevents pigmentation of the skin, prevents stains and freckles, and at the same time whitens the skin. When the melanin production inhibitor of the present invention is applied to the skin, aminobenzoic acid, which is an active ingredient, acts on the melanogenic cells of the skin to reduce the production of melanin, and thus the pigmentation is improved and the skin is whitened. .

The melanin production inhibitor of the present invention may be in any dosage form as long as it can be applied externally. Specific examples include creams, emulsions, lotions, ointments and the like. Further, compounding ingredients other than aminobenzoic acid, cosmetics, quasi-drugs, various components usually used in pharmaceuticals, for example, solvents such as alcohol, solubilizers, humectants, fragrances, colorants, preservatives,
Viscosity modifiers and the like may be appropriately blended as necessary.

[0014]

Example 1 The melanin production inhibitory action and safety of aminobenzoic acid, which is an active ingredient of the melanin production inhibitor of the present invention, were tested.

Suppression of Melanin Production of Cultured Pigment Cells 62500 B-16 mouse melanoma cells, Dulbecco's modified Eagle medium (containing 10% fetal bovine serum, penicillin 100 μg / ml, streptomycin 100 μg / ml)
It was dispersed in 5 ml and seeded in a culture flask (25 cm ² ). After culturing for 1 day in a carbon dioxide incubator set at 37 ° C and 5% CO ₂ , each aminobenzoic acid of ortho, meta and para is adjusted to a concentration of 0, 0.01, 0.1, 1, 10 mM. To 37 ° C. and 5% CO ₂ incubator for 3 days.

The cultured cells were detached and dispersed by trypsin treatment, and the number of cells was counted. After centrifuging these cells, 1 ml of Solen-350 (made by Packard) was added to lyse the cells. Toluene was further added so that the total amount was 2 ml, and the absorbance at 405 nm was measured.
The amount of melanin was calculated. As a comparative example, the same test was performed for arbutin and kojic acid, which are general melanin production inhibitors. The melanin production inhibition rate was calculated from the obtained melanin amount by the following formula. The results are shown in Table 1.

[0017]

[Equation 1]

[0018]

[Table 1]

Aminobenzoic acid inhibited melanin production without affecting the proliferation of cultured pigment cells.
Both arbutin and kojic acid had low inhibition rates of melanin production, while high concentrations affected cell proliferation.

Tyrosinase activity inhibition test 1: Preparation of tyrosinase crude enzyme solution B-16 mouse melanoma cells were treated with Dulbecco's modified Eagle medium (10% fetal bovine serum and penicillin (100 μm).
g / l), streptomycin (100 μg / l) included) 15
37 using a culture flask (75 cm ² ) containing ml
Cultivation was carried out under the conditions of ° C and 5% CO ² . The cells grown by culturing for 2-3 days were treated with trypsin for 3 minutes to be suspended, and centrifuged (450 xg, 3 minutes) to collect the cells.
The obtained cells were washed 3 times with a 10 mM phosphate buffered saline solution (pH 6.8), and the number of cells was counted.

10 million cells were suspended in 10 ml of 0.1M phosphate buffer (pH 6.8) containing 0.1% surfactant (Triton X-100: manufactured by Nacalai Tesque, Inc.), and this was iced. The sonication for 15 seconds was repeated 3 times while cooling. The supernatant was collected by centrifugation and used as a crude tyrosinase enzyme solution.

2: Effect of aminobenzoic acid on the activity of tyrosinase The activity of tyrosinase was determined by the method of Fujinuma et al. (JP-A-60-56).
(See No. 912), and the tyrosinase activity using L-dopa as a substrate was measured. That is, 0.5 ml of a crude tyrosinase enzyme solution and a 0.1 mM 50 mM phosphate buffer solution (pH 6.8; hereinafter referred to as a buffer solution) of aminobenzoic acid to be tested 0.1
Mix ml and add 0.9 ml of buffer to 37 ℃
And warmed for 3 minutes. An additional 0.5 ml of a 0.067% buffer solution of L-DOPA was added thereto, and the mixture was kept at 37 ° C.
The change in absorbance at 75 nm with time was examined. The tyrosinase activity was calculated from the obtained initial rate of change in absorbance, and the inhibition rate was calculated from the following formula. The results are shown in Table 2.

[0023]

[Equation 2]

[0024]

[Table 2]

From this example, it was shown that aminobenzoic acid has a tyrosinase inhibitory action. However, although the meta form shows a strong melanin production inhibitory effect as obtained in Example 1, the inhibitory effect on tyrosinase activity is not so strong even at a high concentration. It is suggested that it has some other effect.

Safety Test of Aminobenzoic Acid by Patch Test Skin Sensitization Test (Patch Test) 10% physiological saline solutions of ortho, meta and para aminobenzoic acids were prepared. The test subjects are 20 men and 20 women aged 20 to 60 years, for a total of 40 people. A closed patch test was performed by applying a fin chamber filter paper, in which the sample and the control solution (saline solution) were immersed in the chamber part of the fin chamber, to the upper arm flexion of the subject.

The application time was 24 hours, and after 24 hours, the fin chamber was removed, and 30 minutes, 24 hours, and 48 hours later, three determinations were made. The criteria for judgment are as follows:

-: No reaction ±: Slight erythema +: Clear erythema ++: Erythema and tumor or papule ++: Blisters are observed. The results are shown in Table 3.

[0029]

[Table 3]

Aminobenzoic acid, which is an active ingredient of the melanin production inhibitor of the present invention, has a very low possibility of inducing irritation reaction and allergic reaction, and is highly safe.

Examples of the composition of the melanin production inhibitor of the present invention are shown below. These do not limit the invention. %
Indicates% by weight.

[0032]

Example 2

[0033]

Example 3

[0034]

Example 4

[0035]

Example 5

[0036]

Example 6

[0037]

EFFECT OF THE INVENTION Aminobenzoic acid, which is an active ingredient of the melanin production inhibitor of the present invention, has melanin production inhibitory activity and is highly safe. Therefore, the melanin production inhibitor of the present invention is effective for whitening skin. Very useful as an agent.

Continuation of front page (51) Int.Cl. ⁶ Identification number Internal reference number FI Technical indication location A61K 31/195 ADS (72) Inventor Toyokazu Nishino 14-5 Shimokita-cho, Neyagawa-shi, Osaka Kurashiki Spinning Co., Ltd. (72) Inventor Yo Hirota, 220 Kusanagi, Shimizu City, Shizuoka Prefecture 43 (56) Reference JP-A-5-117136 (JP, A)

Claims (1)

[Claims] 1. Formula (I): A melanin production inhibitor containing aminobenzoic acid.