Antioxidant and hepatoprotective effects of dried flower extracts of hibiscus sabdariffa l. on rats treated with carbon tetrachloride.

The hypolipidemic, antioxidative and hepatoprotective activities of 200 and 300mg/kg body weight ethanolic extract of dried flower of Hibiscus sabdariffa L. (HSE) were assessed in rats treated with 0.25ml/kg body weight (intraperitoneally) of carbon tetrachloride (CCl4). Hepatic malondialdehyde (MDA), serum lipid profile, serum vitamins A, C and β- carotene, alanine transaminase (ALT), aspartate transaminase (AST) and alkaline phosphatase (ALP) activities were measured. The oral administration of the extracts showed a significant (P<0.05) dose-dependent decrease in the CCl4- induced MDA formation in liver. Also HSE pretreatment, showed a significant increase in HDL-C concentration and decrease in the levels of total cholesterol, LDL-C and TG as compared to control. The levels of vitamins A, C, and β- carotene were shown to be significantly (P<0.05) decreased and increased respectively in CCl4 and HSE treated groups when compared with the control. The increase in the levels of these vitamins might not be unconnected with the antioxidant properties possessed by the extract. The extract also displayed a strong hepatoprotective effect as it significantly reduced CCl4- induced hepatotoxicity in rats, as judged from the serum activities of ALT, AST, and ALP. These results suggest that the ethanolic extract of dried flower of Hibiscus sabdariffa L. possesses antioxidant, hepatoprotective and hypolipidemic effects on CCl4-induced oxidative stress in rats.