EA501

An antitumor polysaccharide, EA3 isolated from a Japanese edible mushroom, Flammulina velutipes (CURT. ex FR.) SING. is composed of D-glucose. Studies to determine its structure were performed by mean of partial acid hydrolysis, acetolysis and the chemical analysis of the complete hydrolysates of the fully methylated polysaccharide. Thus the chemical structure of EA3 was found to be that of a beta-(1 leads to 3)-glucan. Another antitumor polysaccharide (EA5) also isolated from F. velutipes was fractionated on a concanavalin A-Sepharose 4B column. The active antitumor component was further purified by column chromatography on Sephadex G-200. Among the polysaccharides isolated the highest molecular weight polysaccharide (EA501) showed the highest rate of antitumor activity. The component sugar of EA501 were found to be D-glucose 42.3%, D-galactose 17.3%, D-mannose 12.2%, D-xylose 6.7% and L-arabinose 14.7%.