| 摘要 |
PROBLEM TO BE SOLVED: To obtain a physiologically active extract which exhibits various physiological effects, e.g. antimicrobial effect, antiviral effect, antitumor effect, and the like, on the mammals containing human beings, shows no toxicity and is useful for foods, cosmetics and medicines by extracting an ethyl acetate- soluble component from fresh Polygonum tinctorium. SOLUTION: This physiologically active extract is prepared by immersing fresh Polygonum tinctorium in an organic solvent (e.g. methanol, ethyl acetate, or the like) to extract an ethyl acetate-soluble component and collecting the component. It is favorable that the fresh Polygonum tinctorium is collected prior to fructification and a part or the whole of the fresh terrestrial part is washed with water, immersed in an organic solvent of a 1-100 fold amount in volume and extracted for 0.1-100 hr under warming. Although the extract obtained by the above method is usable even in the same form as in just after prepared, it is favorable to remove an insoluble content by means of filtration, fractionation, fractional precipitation, decantation and/or centrifugal separation, then distill off the organic solvent and purify by means of salting, out or the like, depending on the final use. |
