Antioxidant properties of extracts from juemingzi ( Cassia tora L.) evaluated in vitro

Methanol extract from juemingzi ( Cassia tora L.) was fractionated by liquid–liquid partition using ethyl acetate, n-butanol and water, respectively. The antioxidant activity of three different fractions was evaluated using different antioxidant tests, including inhibition of peroxidation of linoleic acid, reducing power, free-radical scavenging and ferrous ions chelating activity. In the above four assays, all the fractions showed antioxidant potential to varying degrees. Among these fractions, ethyl acetate fraction exhibited more antioxidant potency than other fractions. Furthermore, ethyl acetate fraction was found to be more effective in protecting LDL against oxidation in a concentration-dependent manner. The data suggest that juemingzi especially ethyl acetate-soluble fraction may have a preventive effect against atherosclerosis by inhibiting LDL oxidation.