The inhibitory effects of methanol extracts of 20 herb species on human pla
telet aggregation were investigated. Allspice, basil, marjoram, tarragon an
d thyme strongly inhibited the platelet aggregation induced by collagen. Ba
sil, marjoram and tarragon strongly inhibited platelet aggregation induced
by ADP. An active compound, arbutin, was isolated from sweet marjoram as an
inhibitor of platelet aggregation induced by collagen; ADP, arachidonic ac
id (AA) and thrombin. (C) 1998 John Wiley & Sons, Ltd.