The aqueous extract of T. chebula protected the antioxidant enzymes from reactive oxygen species (ROS) produced by gamma radiation in the rat liver microsomes and mitochondria 5. The ethanolic extract of the fruits of T. chebula decreased the level of lipid peroxidase in albino rats 46. Both treatment and pretreatment of the cultured rat primary hepatocytes with T. chebula aqueous fruit extract (500 or 1000 mg/kg body weight for 5 days) significantly reversed the t-BHP-induced cell cytotoxicity and lactate dehydrogenase leakage. In addition, T. chebula extract exhibited in vitro ferric-reducing antioxidant activity and 2,2-diphenyl-1-picryhydrazyl free radical-scavenging activities. Histopathologic examination of the rat livers showed that T. chebula extract reduced the incidence of liver lesions including hepatocyte swelling and neutrophilic infiltration, and repaired necrosis induced by t-BHP 47. Further, a hepatoprotective compound, isolated from the ethanolic extract of the fruits of T. chebula, was identified as a mixture of chebulic acid and its minor isomer, neochebulic acid that also reduced the tert-butyl hydroperoxide (t-BHP)-induced cell cytotoxicity in isolated rat hepatocyte experiment 48. An aglycone isolated from the fruits of T. chebula, triethylchebulate, significantly inhibited FeSO4 /Cys-induced microsomes lipid peroxidation and protected both H2O2- -induced RBCs hemolysis and RBCs auto-hemolysis in a dose-dependent manner. Furthermore, triethylchebulate demonstrated potent DPPH free-radical scavenging ability and moderately suppressed azide-induced mitochondria ROS formation. The results demonstrated that triethylchebulate was a strong antioxidant and free-radical scavenger, which might contribute to the anti-oxidative ability of T. chebula