Antiplatelet Aggregation Potencies of some Allium spp. Grown in Indonesia

Several species and varieties of Allium spp. grown in Indonesia were screened for their in vitro antiplatelet aggregation activities. The extracts were also analyzed by GC for their volatile sulfur-containing compounds, and measured for their Volatile Reducing Substances (VRS) contents. Antiplatelet aggregation potencies of Allium spp. were varied among the species and varieties studied. Garlic extracts showed the greatest ability to inhibit platelet aggregation followed by extract of shallot, chive, yellow onion, and green onion. The 'Jawi' and 'local Padang' variety of garlic showed high activities with $IC_{50}$ values of 9.1 and $9.8\;{\mu}g/ml$, respectively. The local Kupang variety of shallot showed the highest antiplatelet activity among the shallot varieties evaluated, with an $IC_{50}$ value of $111\;{\mu}g/ml$. Antiplatelet aggregation activities of Allium extracts showed a positive correlation with the level of volatile compounds.