377 Differential Human Antiplatelet Activity of Selected Allium Thiosulfinates

• Published in: HortScience Vol. 34; no. 3; p. 509
• Main Authors: Briggs, W.H, Xiao, H, Parkin, K.L, Goldman, I.L
• Format: Journal Article
• Language: English
• Published: 01.06.1999
• ISSN: 0018-5345; 2327-9834
• DOI: 10.21273/HORTSCI.34.3.509A

The acute syndromes associated with many human diseases of the cardiovascular system such as myocardial infarction, angina, and some forms of stroke are caused by thrombosis. Platelet aggregation plays a central role in thrombus formation. Dietary intake of inhibitors of aggregation may provide protection against these disorders, which effect millions of Americans. Previous research in our laboratory has shown that juice from onion ( Allium cepa ) inhibits platelet aggregation ex vivo. Various sulfur-containing compounds are largely responsible for the distinctive aromas, flavors, and platelet inhibitory actions of onion. Among these is the thiosulfinate (TS) family of compounds formed upon maceration of the vegetable. In this study, several pure Allium compounds were evaluated for antiplatelet activity. TSs were synthesized in model reaction mixtures containing the enzyme allinase and S-alk(en)yl-L-cysteine sulfoxides (ACSOs), their natural precursors, or purified from garlic juice. Antiplatelet activity of each compound was determined by dose response using whole blood from human donors. A minimum of 0.4 mM methyl methaneTS, a compound found in freshly cut onion and garlic ( Allium sativum ), was needed to significantly inhibit aggregation relative to a non-TS control. By contrast, a lower concentration (0.05 mM) of 2-propenyl 2-propeneTS (allicin) and propyl propraneTS, compounds found in garlic but not onion, was required. The garlic compound methyl 2-propeneTS significantly inhibited at 0.2 mM. These data imply a role of alk(en)yl groups in TS antiplatelet efficacy. Variability in ACSO-derived TS composition in cut onion tissue may explain differential antiplatelet activity of onion cultivars. Results from this investigation suggest that ACSO and TS composition profiles may be useful for evaluating the medicinal value of Alliums .