Antioxidant activity of extracts from Euryale ferox seed.

Euryale ferox has been widely used in traditional oriental medicine to treat a variety of illness. However, very little is known about the cellular actions by which this plant mediates its therapeutic effects. Various aspects of antioxidant activity were evaluated in total extracts and fractions derived from Euryale ferox. Total extracts (IC50 5.6 microg/ml) showed relatively high level radical scavenging activity toward 1, 1-diphenyl-2-picrylhydrazyl (DPPH) and also enhanced viability of Chinese hamster lung fibroblast (V79-4) cells under exposure to oxidative agents. Upon further fractionation, the highest levels of DPPH radical scavenging and lipid peroxidation inhibitory activities were found in the ethyl acetate and butanol fractions. The ethyl acetate fractions, the butanol fractions, and total extracts of Euryale ferox also dose-dependently enhanced the activities of superoxide dismutase, catalase and glutathione peroxidase in V79-4 cells. Of these three antioxidant enzymes, glutathione peroxidase activity was most strongly induced. Taken together, our findings show that Euryale ferox contains a significant antioxidant activity and that specific components in the ethyl acetate and butanol fractions may play an important role in mediating these antioxidant properties.