Comparative studies on antioxidant properties of catharanthus rosea and catharanthus alba

Abstract

Free radicals are fundamentals to any biochemical process and represent an essential part of aerobic life and metabolism and play a dual role in our body as both deleterious and beneficial species. In low/moderate concentrations, free radicals are involved in normal physiological functions but excess production of these species or decrease in antioxidant level leads to oxidative stress. The adverse effects of oxidative stress on human health have become a serious issue. Majority of the diseases/disorders are mainly linked to oxidative stress generated due to free radicals. The plant sources are rich of antioxidants, phyto-constituents which are capable to terminate free radical reactions and prevent our body from oxidative damage. Current research is therefore directed towards finding naturally occurring antioxidant of plant origin. In Indian system of medicine Catharanthus roseus is used in Ayurvedic medicines for number of ailments. The present study deals with comparative evaluation of antioxidant potential of ethanolic extracts of the roots of the two varieties of Catharanthus roseus L. namely 'rosea'(pink flowers) and 'alba'(white flowers) using different systems of assay, e.g. Hydroxyl radical-scavenging activity, superoxide radical-scavenging activity, DPPH radical- scavenging activity and nitric oxide radical inhibition method. The results revealed that the ethanolic extracts of the roots of Periwinkle varieties extracts exhibited satisfactory scavenging effect in all the radical scavenging assays in a concentration dependent manner; however Catharanthus rosea had more antioxidant activity than Catharanthus alba.