Abstract: The yield of active polysaccharides contained in Agaricus blazei, such as ?-glucan, can be improved, by decomposing and treating the mycelium or fruit body of Agaricus blazei or a liquid waste of the culture of the mycelium with an enzymatic agent principally comprising hemicellulase. By increasing the concentrations of the active polysaccharides, furthermore, the digestion and absorption of the biologically active substance of the present invention after the incorporation thereof into bodies is prominently elevated, so that the active substance can exert excellent immune activation effect on cancers and other adult diseases.

Abstract: The yield of active polysaccharides contained in Agaricus blazei, such as &bgr;-glucan, can be improved, by decomposing and treating the mycelium or fruit body of Agaricus blazei or a liquid waste of the culture of the mycelium with an enzymatic agent principally comprising hemicellulase.