Abstract

Leaf extracts from Chilean bean landraces were assessed for antiplatelet activity using different assays in vitro. Lyophilized MeOH:H2O 7:3 (v/v) and EtOH:H2O 7:3 (v/v) leaf extracts from the Chilean landraces Coscorron, Frutilla, Magnum, Sapito and Tortola were compared for platelet aggregation effect by turbidimetry and flow cytometry. The HPLC-DAD study allowed the identification of caffeoyl malic acid, derivatives of quercetin and kaempferol. The results showed that the EtOH:H2O 7:3 extracts have higher antiplatelet capacity, with better effects for the Frutilla and Sapito landraces (IC50 0.38 +/- 0.05 and 0.16 +/- 0.08 mg/mL, respectively). The Sapito extract inhibited P-selectin expression, CD63 secretion, and concentration-dependent GPIIb/IIIa activation. The activity was associated with the main phenolics content, including rutin, caffeoyl malic acid and kaempferol 3-Oglucoside. The findings add evidence for the potential of bean leaves as greens, affording naturally occurring compounds with health promoting properties, including inhibition of platelet aggregation in vitro.