Antiplasmodial procyanidins derivatives from Chinese Hawthorn

The methanolic extract of the leaves of Chinese Hawthorn was investigated for its activity against chloroquine-sensitive strains of Plasmodium falciparum using the method of parasite lactate dehydrogenase assay. Four oligomeric procyanidins, such as epicatechin-(4β→8)-epicatechin-(4β→8)-epicatechin (1), epicatechin-(4β→8)-epicatechin-(4β→6)-epicatechin (2), epicatechin-(4β→6)-epicatechin-(4β→8)-epicatechin (3), and epicatechin-(4β→8)-epicatechin-(4β→8)-epicatechin-(4β→8)-epicatechin-(4β→8) (4), were isolated and evaluated for in vitro antiplasmodial activity, as well as for their cytotoxic potential on SK-OV-3 cancer cell lines. Three procyanidins showed notable growth inhibitory activity against chloroquine-sensitive strains of P. falciparum with IC(50) values of 2.7 μM (SI values of >55.5). The compounds showed no significant cytotoxicity (IC(50) > 150 μM) toward the SK-OV-3 cancer cell line. This is the first report on the antiplasmodial activity of these oligomeric procyanidins from Chinese Hawthorn.