Total phenolics, flavonoids content and antioxidant activities of some Eulophia species

Abstract

The aim of the study was to determine total phenolics, flavonoid contents and antioxidant activity in some Eulophia species (Orchidaceae). Rhizomes of Eulophia species viz. E. nuda, E. ochreata, E. herbacea, E. ramentacea, E. andamanensis and E. epidendrea were extracted with petroleum ether, methanol, acetone and Distilled water. The antioxidant capacity of the extracts was determined using the ferric reducing antioxidant potential assay, and the free radical-scavenging capacity was evaluated using 2,2-diphenyl-1-picrylhydrazyl radical-scavenging. Maximum amounts of total phenolics and antioxidant activity were observed in methanol extracts of all Eulophia species studied. Acetone proved to be best solvent for extraction of flavonoids in all Eulophia species. Among the species studied, E. nuda showed maximum yield of total phenolic contents, flavonoid contents, and antioxidant activity. The study also revealed that there is strong correlation in phenolics and antioxidant activity.