Anti-platelet aggregation activity of stilbene derivatives from Rheum undulatum.

In continued studies on cultivated Korean rhubarb rhizomes (Rheum undulatum), three known stilbenes (desoxyrhapontigenin, rhapontigenin, piceatannol) have been screened for activity on blood platelet aggregation. Both rhapontigenin and desoxyrhapontigenin exhibited strong inhibition on the aggregation induced by arachidonic acid and collagen. However, piceatannol did not show inhibition. These inhibitory effects may partially contribute to anti-blood stagnancy activity of rhubarb.