Antioxidant activity of methanolic leaf extract of Etlingera fenzlii (Kurz) Skronick.& M.Sabu (Zingiberaceae) - The honey bee repellent endemic plant species of the Andaman Nicobar Islands

Abstract

Etlingera fenzlii (Kurz) Skronick.M they smeared their bodies with the leaf sap and also chewed leaves to spat on to the honey comb. The honey bees there upon flew away from the comb and did not string. It is documented that the volatile constituents of leaves have proved to be effective eco-friendly, possess varying degrees of insect and pest controlling properties. It is also an important folk medicine for malarial fever and gastrointestinal disorders. The present study was performed to investigate the antioxidant activity of methanolic extract of leaves of E. fenzlii . The antioxidant potential of leaf extract was evaluated with methods DPPH scavenging assay and reducing power assay. The extract showed antioxidant activity compared to the reference antioxidant ascorbic acid in a dose dependent manner. In DPPH scavenging assay the IC 50 value of the extract was found to be 42.50μg/ml while the IC 50 value of the reference standard ascorbic acid was 71.31μg/ml. Phenolic content of the leaf extract was also evaluated using Folin-Ciocalteu assay. Total phenolic content of the extract was found to be 53±8.86 µg GAE/mg. The results obtained in the present study indicate that leaves of E.fenzlii have potent antioxidant activity and/or free radical scavenging activity.