Polysaccharides in fungi. XXXV. Anti diabetic activity of an acidic polysaccharide from the fruiting bodies of Tremella aurantia.

An acidic polysaccharide (TAP) was isolated from a hot-water extract of the fruiting bodies of Tremella aurantia. It showed remarkable hypoglycemic activity in normal mice and two diabetic mouse models, streptozotocin-induced diabetes and genetic diabetes, following intraperitoneal administration. Continuous oral administration of TAP solution (0.5g/l) for a long period was found to be also effective in hyperglycemia in glucose-loaded mice and no harmful physical effects were found. TAP had an [alpha]D -7 degrees in water, and its molecular weight was estimated to be about 1500000. TAP is composed of mannose, xylose, glucuronic acid and glucose (molar ratio, 4:2:1:0.3), and it contains 2.2% of O-acetyl groups.