Carbon tetrachloride (CCl(4)) causes chronic hepatitis, featuring an increase in hepatic hydroxyproline, spleen weight and serum GPT levels and a decrease in plasma albumin levels. Crude extracts of fresh whole plants of Anoectochilus formosanus showed inhibition of chronic hepatitis induced by CCl(4) in mice. Bioactivity-guided fractionation and spectroscopic analysis revealed that kinsenoside was the most active compound. In an in vitro study, the LD(50) values for H(2)O(2)-induced cytotoxicity in BALB/c normal liver cells were significantly higher after kinsenoside pretreatment than after vehicle alone, further confirming that kinsenoside shows significant antihepatotoxic activity.