METHOD FOR PRODUCING POLYGONUM TINCTORIUM EXTRACT& xA;

摘要

An object of the present invention is to provide a tryptanthrin-containing indigo-plant leaf extract particularly suitable for application to the skin. The present invention provides a method for producing a tryptanthrin-containing indigo-plant leaf extract, the method comprising filtering a mixture of a concentrated ethanol extract of indigo-plant leaves and a polyhydric alcohol, and collecting the filtrate. The present invention further provides an indigo-plant leaf extract produced by this method.