Studies on the host-mediated antitumor polysaccharides. Part XIV. Antitumor activity and some properties of water-insoluble hetero-glycans from "Himematsutake," the fruiting body of Agaricus blazei Murill.

Abstract

After extraction of a hot-water-soluble polysaccharide (FI) from the fruiting bodies of Himematsutake (Agaricus blazei Murill), water-insoluble polysaccharides were obtained by successive extraction with 1% ammonium oxalate solution (FII), 5% sodium hydroxide solution (Fill and FIV), 20% sodium hydroxide solution (FV), and 5% lithium chloride-dimethylacetamide solution (FVI) in that order. These water-insoluble fractions were further fractionated by ethanol precipitation, gel-filtration, etc. Polysaccharides, polysaccharide-protein complexes, and chitin substances thus obtained were assayed for their antitumor activities using the Sarcoma 180/mice i.p., p.o. method. The heteroglycan-protein complexes, FH-a, -b and -c, obtained from FII had weak antitomor activities. A remarkable antitumor activity was found in a glycoprotein, FIII-2-b, fractionated and purified from Fill. The polysaccharide portion of this polysaccharide-protein complex (polysaccharide, 50.2% and protein, 43.3% each on a weight basis) consisted of (1-*6)-β-D-glucan, and its protein portion was rich in Asx, Glx, Ala, Leu, and Pro. A high antitumor activity was found in a xyloglucan-protein complex, FIV-2-b, fractionated and purified from FIV. Antitumor activity was found also in a glucoxylan, FV-2-a, obtained from FV. No significant antitumor activity was found in a chitin substance, FVI.