Free radical scavenging activity of extracts prepared from fresh leaves of selected Chinese medicinal plants

The free radical scavenging activity of the 80% methanolic extracts from fresh leaves of 300 Chinese medical woody plants was assessed with the aid of the stable DPPH radical. Among the plants screened, 56 species had strong free radical scavenging capacities, with IC50 values lower than 0.5 mg leaves per milliliter. Analysis of the medical uses of these plants showed that most of them are employed for their effects on hemostasis, as antiinflammatory, antimicrobial or for treatment of dysentery. These uses may be directly linked to the content in tannins and flavonoids and consequently to their free radical scavenging activities. (C) 2003 Elsevier B.V. All rights reserved.