Chemical composition and in vitro antioxidant potential of essential oil and rhizome extracts of Curcuma amada Roxb

The chemical composition of hydro-distilled essential oil from rhizomes of Curcuma amada was analysed. Nineteen compounds representing 77.31% of the total essential oil were identified by GC and GC-MS. Rhizomes were extracted by various solvents with different polarities using various antioxidant assay systems. The petroleum ether extract showed potent DPPH radical scavenging activities (IC50=18.98 +/- 0.05) and reducing power (A(700)=0.861 +/- 0.001). Ethyl acetate extract exhibited remarkable nitric oxide radical scavenging activity (IC (50)=5.97 +/- 0.09) higher than that of ascorbic acid (IC50=6.05 +/- 0.02). The essential oil showed promising superoxide radical scavenging activities (IC50=15.30 +/- 0.03g/ml) as compared with ascorbic acid (IC50=15.28 +/- 0.01). The results indicate that the oil and organic extracts from rhizomes of C. amada could serve as an important bioresource of antioxidants for food and pharmaceutical industries.