Water-soluble ginger root extract

Abstract

Provided are a water-soluble ginger root extract which is a water extract or a hydrous alcohol extract of a ginger root and is substantially free of gingerols; and a hair growth inhibitor and a preparation for external use each containing the extract. The water-soluble ginger root extract of the present invention causes less skin irritation because of being substantially free of gingerols, and has excellent body-hair growth inhibiting effects, so that it is useful as a hair grown inhibitor and a preparation for external use, each having a high degree of safety.

What is claimed is:  
     
         1 . A water-soluble ginger root extract which is a water extract or a hydrous alcohol extract of a ginger root and is substantially free of gingerols.  
     
     
         2 . A water-soluble ginger root extract of  claim 1  obtained by (a) extracting the ginger root with water or a hydrous alcohol and then (b) subjecting the water-soluble extract solution to treatment with an adsorbent or liquid-liquid fractionation in a low-polarity solvent.  
     
     
         3 . A water-soluble ginger root of  claim 1  or  2 , wherein the concentration of 6-gingerol is 0.5 ppm or less.  
     
     
         4 . A hair growth inhibitor comprising a water-soluble ginger root extract of  claim 1  or  2 .  
     
     
         5 . A preparation for external use, which comprises a water-soluble ginger root extract of  claim 1  or  2 .