Inhibitory Activity of Extracts from 16 Medicininal Plants against Platelet Aggregation Induced by Thrombin and Analysis of the Active Fraction from Moringa oleifera by GC-MS

PurposeTo evaluate 16 ethanol extracts of medicinal plants collected from Myanmar and several extracts of Moringa oleifera Lam. from China for inhibitory activities against platelet aggregation induced by thrombin and to analyze chemical constituents in the antiplatelet fraction of the extract from M. oleifera.

MethodThe in vitro bioassay for inhibitory activities of these extracts against rabbit platelet aggregation induced by thrombin was conducted and the chemical compositions were analyzed by gas chromatography-mass spectrometry (GC-MS).

ResultsThe ethanol extracts of 16 medicinal plants from Myanmar showed weak inhibitory activities against rabbit platelet aggregation induced by thrombin. At the extract’s final mass concentration of 1 500 μg/mL, the extracts of M. oleifera leaves (MMV201-1), Lepidium sativum L. seeds (MY46), Aconitum ferox Wall. ex Ser. Roots (MY53), and Centella asiatica (L.) Urb. whole plants (MY89) possessed inhibition rates of 27.0%±4.2%, 20.0%±12.7%, 20.4%±6.0%, and 20.5%±1.3%, respectively, while inhibition rates of other extracts were less than 20%. At the extract’s final mass concentration of 1 000 μg/mL, the CH₂Cl₂ fraction (PXS58-3-1) of the extract from M. oleifera leaves, collected from Dehong, Yunnan, possessed an antiplatelet aggregation activity with an inhibition ratio of 28.2%±17.8%. Ten compounds in the active fraction, PXS58-3-1, were detected by GC-MS. 2-Pyrrolidinone (44.58%), nicotinamide (23.05%), and palmitic acid (9.74%) were major constituents.

ConclusionThe antiplatelet activities of Lepidium sativum and Aconitum ferox are worthy to be further studied. The antiplatelet constituents of M. oleifera need to be clarified in the next research.