Comparative screening of plant essential oils: phenylpropanoid moiety as basic core for antiplatelet activity.

Essential oils extracted from different plants (Anthemis nobilis L., Artemisia dracunculus L., Cannabis sativa L., Cupressus sempervirens L., Cymbopogon citratus (DC.) Stapf., Curcuma longa L., Foeniculum vulgare L., Hypericum perforatum L., Hyssopus officinalis L., Mentha spicata L., Monarda didyma L., Ocimum basilicum L., Ocotea quixos Kosterm., Origanum vulgare L., Pinus nigra J.F. Arnold, Pinus silvestris L., Piper crassinervium Kunth., Rosmarinus officinalis L., Salvia officinalis L., Salvia sclarea L., Santolina chamaecyparissus L., Thymus vulgaris L., Zingiber officinaie L.) were screened in guinea pig and rat plasma in order to assess antiplatelet activity and inhibition of clot retraction. The oils were chemically analysed and a relationship between components and ability to affect hemostasis was evidenced. O. quixos, F. vulgaris, and A. dracunculus showed the highest antiplatelet activity against ADP, Arachidonic Acid and the Thromboxane A2 agonist U46619 (IC50, 4-132 microg ml(-1)), and a good ability to destabilize clot retraction (IC50, 19-180 microg ml(-1)). For these oils a significant correlation between antiplatelet potency and phenylpropanoids content (54-86%) was evidenced thus suggesting a key role for this moiety in the prevention of clot formation. These findings provide the rationale to take in account the antiplatelet activity in the pharmacological screening of natural products containing phenylpropanoids.