Abstract

Garlic (Allium sativum L.) is used as a traditional medicine throughout the world for the treatment of a variety of diseases. Dietary garlic has been recognized for its beneficial health effects. In particular, garlic consumption has been correlated with: (i) reduction of risk factors for cardiovascular diseases and cancer; (ii) stimulation of immune function; (iii) enhanced detoxification of foreign compounds; (iv) hepatoprotection; (v) antimicrobial effect, (vi) antioxidant effect, and most importantly, (vii) its hypoglycemic and anticoagulant properties. Due to these beneficial properties, garlic and its closely related genera, which includes Tulbaghia violacea, may be useful in the therapy of cardiovascular disease. Platelets were exposed to various extracts of T. violacea to determine their effects on platelet aggregation, adhesion and protein secretion in both in vitro and ex vivo models. It was noted that the organic bulb extract had a higher inhibition on platelet aggregation and adhesion than the positive control, aspirin. It reduced clotting times in the prothrombin time test (PT), but prolonged the clotting time in the activated partial thromboplastin time (APTT) assay in the ex vivo model displaying its antithrombotic ability. The bulb organic extract increased the D-dimer and fibrinogen-C concentrations in the in vitro model, but had no effect on the D-dimer concentrations and lowered the fibrinogen-C results in the ex vivomodel. This study has demonstrated that an organic extract of T. violacea has a beneficial effect similar to that of garlic on the cardiovascular system.

Key words: Anti-platelet, anticoagulation, antithrombic, fibrinogen-C, Tulbaghia violacea.