In the course of isolating preventive agents from sepsis based on the in vivo assay model from the EtOAc extract of the roots of Saururus chinensis, twelve lignans, sarisan (1), erythro-austrobailignan-6 (2), meso-dihydroguaiaretic acid (3), saucerneol B (4), manassantin B (5), manassantin A (6), rel-(8R,8'R)-dimethyl-(7S,7'R)-bis(3,4-methylenedioxyphenyl)tetrahydro-furan (7), (+)-saururinone (8), sauchinone (9), sauchinone B (10), nectandrin B (11) and machilin D (12), were isolated. Compounds 9 and 10, at a dose of 10 mg/kg, increased survival rates to 80% from 20% for the control experiment, and decreased the plasma levels of tumor necrosis factor-alpha (TNF-alpha) and alanine aminotransferase (ALT) activity in mice administered LPS/D-GalN.