1997 Volume 20 Issue 7 Pages 776-780
Two lignans, asarinin (6) and xanthoxylol (7), were isolated from the radix of Asiasarum heterotropoides var. mandshuricum, which consist of a kampo prescription, Shouseiryu-to, as inhibitors of Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA). These lignans also exhibited remarkable inhibitory effects on a two-stage carcinogenesis test of mouse skin and pulmonary tumors. Furthermore, it was confirmed that these hydrophobic lignans dissolved in the water decoction of Shouseiryu-to, and these lignans might be among the active consituents of this kampo prescription in terms of its anti-tumor-promoting activity.