Antioxidant properties of different fractions of tubers from Pueraria tuberosa Linn

Pueraria tuberosa Linn. (PT), Leguminosae, is a perennial climber, growing throughout tropical parts of India. In the Ayurvedic system of medicine, it is used as a drug of choice to manage pain, inflammation and other related diseases. The antioxidant potency of P. tuberosa was investigated for the first time. Total antioxidant capacity was determined using an ABTS∗+ assay. Lipid peroxidation was assessed in terms of thiobarbituric acid-reactive substances by using egg-yolk homogenates as lipid-rich media. Superoxide radical-scavenging was measured using riboflavin-light-nitro blue tetrazolium (NBT) assay. Hydroxyl radical trapping potential was determined by evaluating hydroxyl radical induced deoxyribose degradation using thiobarbituric acid method. In order to assess the metal chelation property, hydroxyl radical induced deoxyribose degradation was evaluated in the absence of ethylenediaminetetraacetic acid. Both hexane and methanol fractions inhibited lipid peroxidation and also chelated the iron, showing potent antioxidant property.