Antioxidant and hepatoprotective activity of a lichen Usnea ghattensis in vitro.

Antioxidative and hepatoprotective activity of a cultured lichen Usnea ghattensis has been studied. The methanolic extract of cultured lichen U. ghattensis showed good antioxidant activity by preventing lipid peroxidation by 67% and 86% in Trolox-equivalent antioxidant capacity at 20 microg/ml. It also showed superoxide, 1,1-diphenyl-2-picrylhydrazyl, nitric oxide, and hydroxyl radical-scavenging activity, 89%, 89.6%, 94.8%, and 89.6%, respectively, and found levels higher then that known for the synthetic antioxidants butylated hydroxytoluene, butylated hydroxyanisol, and quercetin at 20 microg/ml concentration. The cultured lichen extract also showed hepatoprotection against ethanol-induced toxicity in the mice liver slice culture model by a significant decrease in the antioxidant enzymes, glutathione peroxidase, catalase, and superoxide dismutase, along with a decrease in lipid peroxidation and lactate dehydrogenase release.