In Vitro Antioxidant and Hepatoprotective Activity of Ethanolic Extract of Bacopa monnieri Linn. Aerial Parts

The ethanol extract of Bacopa monnieri Linn. (Schrophulariaceae) aerial parts (EBM) was investigated for any in vitro and in vivo antioxidant and hepatoprotective effects. EBM was prepared and estimation of total phenolics was carried out. Further, the antioxidant activity of EBM was studied using four in vitro models. The amount of total phenolics was estimated to be 47.7 (g of pyrocatechol equivalent per mg of extract. The reducing power of the extract was found to be concentration dependant. The antioxidant activity, nitric oxide scavenging activity and superoxide radical scavenging activity was also concentration dependant with IC 50 value being 238.22 g/ml, 29.17 g/ml and 22.92 g/ml respectively. The activities were found to be comparable with the reference drugs. Different groups of animals (Wistar albino rats) were administered with paracetamol (500 mg/kg, p.o., once in a day for 7 days). EBM at the dose of 300 mg/kg/day and silymarin 25 mg/kg/day were administered to the paracetamol treated rats for seven days. The effects of EBM and silymarin on serum transaminases (SGOT, SGPT), alkaline phosphatase (ALP), bilirubin (Direct and Total), cholesterol (HDL and Total) and total protein were measured in the paracetamol-induced hepatotoxic rats. Further, the effects of the extract on lipid peroxidation (LPO), glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) were estimated. EBM and silymarin produced significant (P < 0.05) hepatoprotective effect by decreasing the activity of serum enzymes, bilirubin, total cholesterol and in vivo lipid peroxidation and significantly (P < 0.05) increasing the levels of GSH, SOD, CAT and HDL cholesterol. EBM also showed antioxidant effects on FeCl 2 -ascorbate-induced lipid peroxidation in rat liver homogenate. From these results, it was suggested that EBM could protect the liver cells from paracetamol-induced liver damage perhaps, by its antioxidative effect on hepatocytes, hence eliminating the deleterious effects of toxic metabolites from paracetamol.