An Evaluation of the Preventive Effect of the Methanol Extract of Thai Basil (Ocimum basilicum L.) on Ethanol-induced Hepatotoxicity in Rats

Abstract

Aim: The present study was investigated the preventive effect of methanol extract of Ocimum bacilicum (MOEB) on ethanol induced hepatotoxicity in rats. Study Design: Male Wistar rats weighing 200–250 g were divided into six groups of six rats each as follows: the normal control rats we read ministered with distilled water(NC), the ethanol control was administered with ethanol (5 g/kg)(EC), extract treated group given only the extract (120 mg/ kg body)(ET) and experimental groups EX1 to  EX3 were fed  with ethanol (5 g/kg) plus MOEB in graded doses of 80 mg, 120 mg and 160 mg/kg body for 30 days. Place and Duration of Study: This study was conducted at the Department of Biological Sciences (DBS) of University of Botswana between July 2009-June 2010. Methodology: At the end of the experiment, rats were sacrificed; blood and liver tissue were collected to conduct the bioassays.  From the blood collected, thiobarbituric acid-reactive substances (TBARS), reduced glutathione (GSH), catalase (CAT) and superoxide dismutase (SOD) were estimated together with the liver markers such as alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP). From the liver tissue collected, about 10 small pieces were fixed in 10% formalin for histological preparations and the rest was used for bioassays such as TBARS, GSH, CAT and SOD. Results: The results indicated that there were significant difference between the experimental rats (EX-groups) when compared with alcohol control (EC-group) in all the parameters checked and they were not significantly different from the normal control (NC-group). Again, the groups, treated with extracts only, did not show any negative effect, which clearly indicated that the extract had no toxic effects. A significant reduction in the levels of TBARS, ALT, and AST and a significant increase in the levels of GSH, CAT and SOD were noticed in EX groups when compared with the EC groups. Thus the results indicated a significant protection by these extracts against ethanol-induced hepatotoxicity (P ≤0.05). Conclusion: The present study showed that MEOB is a potent antioxidant agent in preventing and controlling the hepatotoxicity induced by ethanol and induce a protective effect by decreasing the oxidative stress and increasing the antioxidant status.