Antioxidant and hepatoprotective activity of ethanolic extract of leaves of Solidago microglossa containing polyphenolic compounds

The antioxidative and hepatoprotective potential of Solidago microglossa D.C. a widely used medicinal plant from Brazil was investigated. The leaf extract showed inhibition against thiobarbituric acid reactive species (TBARS) induced by different prooxidants (10 mu M FeSO4 and 5 mu M sodium nitroprusside SNP) in rat liver, brain and phospholipid homogenates from egg yolk. Moreover, the free radical scavenging activities of the extract was evaluated by the scavenging of 2,2-diphenyl-1-picrylhydrazyl (DPPH) (IC50, 3.8 +/- 0.5 mu g/ml) and hydroxyl radical on benzoic acid hydroxylation (IC50. 32.3 +/- 1.3 mu g/ml) and deoxyribose (IC50. 39.1 +/- 2.4 mu g/ml) assays. The ethanolic extract showed significant hepatoprotective activity against paracetamol (250 mg/kg) induced liver damage in mice in a dose dependent manner. The phenolic composition and their quantification by high performance liquid chromatography (HPLC) resulted in the identification of gallic acid and flavonoids: quercetrin (quercetin-3-O-rhamnoside), rutin (quercetin-3-O-rutinoside) and quercetin. (C) 2011 Elsevier Ltd. All rights reserved.