ABSTRACT:
Adhatoda vasica and Terminalia chebula are the important medicinal plants widely used as a herbal medicine in south India. In the present study, the ethyl acetate extracts of two plants were screened for free radical scavenging activity in two different in vitro systems. DPPH radical scavenging activity and superoxide radical scavenging activity in KH2PO4-KOH/NBT/EDTA system. Total antioxidant activity was measured using ascorbic acid as a standard. Both the plants extracts exhibited wide range of DPPH free radical scavenging activities with increase of dosage concentration from 10 to 50 µl. T. chebula showed an increase of DPPH free radical scavenging activity from 15.5 to 84.3 % with the increase of plant extract dosage. Whereas, A. vasica showed an increase of DPPH free radical scavenging activity from 12.3 to 76.8 %. Also, superoxide scavenging activity of T. chebula was found to be higher (84.3%) compared to A. vasica (78.4%), which was obtained at 100 µg/ml concentration of plant extract. Further phytochemical analysis of plant extracts, confirms that antioxidant property of A. vasica and T. chebula was because of due to presence of phenols and flavonoids and more antioxidant property of T. chebula was due to presence of high phenolic (388 mg/g) and flavonoid content (27.11 mg/g) compared to A. vasica.