Anticoagulant effect of polyphenols-rich extracts from black chokeberry and grape seeds

Blood coagulation consists of a series of zymogens that can be converted by limited proteolysis to active enzymes leading to the generation of thrombin. Fresh plasma and human thrombin was incubated with extracts from berries of Aronia melanocarpa or seeds of Vitis vinifera (0.5; 5; 50 mu g/ml). The in vitro experiments showed that both extracts prolonged clotting time and decreased the maximal velocity of fibrin polymerization in human plasma. Moreover thrombin incubation with both extracts results in the inhibition of amidolytic activity of this enzyme. It gives hopes for development of diet supplements, which may be preventing thrombosis in pathological states. (C) 2011 Elsevier B.V. All rights reserved.