The powdered fruit bodies of shiitake (Lentinus edodes) showed antitumor activity when given orally to mice. The growth of tumors, both syngeneic and allogeneic, was inhibited by 57.9 to 78.6% in shiitake-fed mice. The degree of inhibition was proportional to the consumption of the experimental diet (L-feed) and was evident even when the administration was started from the 7th day after tumor implantation. The inhibition of tumor growth was mainly due to a glucan contained in the fruit bodies, but the lipid fracton also had inhibitory effects, although mild. Feeding of the fruit bodies to mice in the diet was found to augment both the ability of macrophages to phagocytose latex particles and the spreading activity of the macrophages.

No abstract