Identification by LC-ESI-MS of flavonoids responsible for the antioxidant properties of Mallotus species from Vietnam

Several Mallotus species (Euphorbiaceae) are used in Vietnam as edible plants or as traditional medicines for different indications, some related to the treatment of inflammatory diseases. This study investigated the antioxidant activities of 33 samples from 17 Vietnamese Mallotus species. We also evaluated potential cytotoxic activity against human cervix carcinoma HeLa and human lung fibroblast WI-38 cells. Our aim is to develop safe dietary supplements with a protective effect against various diseases caused by tissue damage and the acceleration of the aging process linked to reactive oxygen species. These tests allowed the identification of non-cytotoxic plant species exhibiting significant antiradical properties. These antioxidant properties may be explained by their polyphenol composition. The antioxidant activity of the most active Mallotus species was further analyzed with and without tannins removal. We also identified by LC-ESI-MS some flavonoids responsible for a part of this activity.