This is a 371 of PCT/JP99/05474, submitted Oct. 5, 1999.
1. Technical Field
The present invention relates to a skin preparation for external use and cosmetics which exhibit excellent effects of ameliorating roughening of the skin and retarding aging of the skin.
2. Background Art
Hitherto, application of soybean extract or soymilkxe2x80x94which is a specific type of soybean extractxe2x80x94to cosmetics has been known, and a number of reports have confirmed its whitening effect. Of such applications, example applications of a fermentation product of soymilk (hereinafter referred to as fermented soymilk) in the field of cosmetics include cosmetics making use of the action of a microorganism belonging to genus Rhizopus (Japanese Patent Application No. 1-102011) and those making use of the action of lactic acid bacteria (Japanese Patent Application No. 3-127713).
However, no published report has mentioned that fermented soymilk is effective in retarding wrinkle formation caused by aging or UV rays, or in ameliorating roughening of the skin.
Accordingly, an object of the present invention is to provide a skin preparation for external use which can ameliorate such conditions of roughening of the skin and formation of wrinkles.
In view of the foregoing, the present inventors have conducted extensive researches, and quite surprisingly, have found that when a fermentation product obtained by causing a microorganism belonging to genus Bifidobacterium to act on a soybean extract is subjected to extraction with an organic solvent, there can be obtained a fermented soybean extract which can ameliorate such conditions of roughening of the skin and formation of wrinkles, thus leading to completion of the invention.
Accordingly, the present invention provides a skin preparation for external use which contains a fermented soybean extract prepared by extracting with an organic solvent a fermentation product obtained by treating a soybean extract with one or more microorganisms selected from bifidobacteria.