Abstract
Sageretia thea (Osbeck) M.C.Johnst., an evergreen tender shrub of the Rhamnaceae, has been used as folk medicine and in traditional tea. To the best of our knowledge, this is the first study that investigates the free radical scavenging activity and cell cytotoxicity of S. thea branches. The ethyl acetate fraction and n-butanol fraction were identified to be rich in phenolic compounds exhibiting impressive antioxidant activity after stepwise partitioning of solvent fractions of the methanol extracts of S. thea branches (MB). Among the different human cancer cells tested, maximum cytotoxicity was found in MDA-MB-231 human breast cancer cells with MB, chloroform, ethyl acetate, n-butanol and water fraction. A significant (p<0.05) correlation between antioxidant activities and cytotoxicity exists in each fraction. These results suggest the branches of S. thea can be a valuable source of antioxidants, and they can serve as natural anticancer constituents in nutraceutical and pharmaceutical applications.