Planta Med 2007; 73 - P_218
DOI: 10.1055/s-2007-986999

Antimalarial properties of galloylated epicatechin derivatives: a first report

AR Sannella 1, J Anke 2, A Hensel 2, FF Vincieri 3, C Severini 1, G Maiori 1, AR Bilia 3
  • 1Department of Infectious, Parasitic and Immunomediated Diseases, Vector-Borne Diseases and International Health Section, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy
  • 2University of Münster, Institute of Pharmaceutical Biology and Phytochemistry, Hittorfstr. 56, D-48149Münster, Germany
  • 3Department of Pharmaceutical Sciences, University of Florence, Via U. Schiff 6, I-50019 Sesto Fiorentino, Florence, Italy

Malaria is one of the most important tropical diseases. According to the World Health Organization (WHO), between 300 and 660 million clinical cases of malaria occur every year and more than 1 million persons are killed by malaria annually [1]. Due to the increasing development of resistant strains of Plasmodium falciparum, the development of a new antimalarial substance with a new chemical skeleton, and probably having a novel mode of action, is a global health priority.

Plant natural products have always played a key role in the discovery of antimalarial agents and recently we reported on the antimalarial activity of a standardised extract of green tea as well as two of its main constituents. Epigallocatechin-3-O-gallate (IC50 ˜30µM for 3D7 strain) and epicatechin-3-O-gallate (IC50 ˜7µM for 3D7 strain), strongly inhibit Plasmodium falciparum growth in vitro [2]. Thus, in continuing the study on this class of constituents, five galloylated proanthocyanidin dimers and trimers isolated from Rumex acetosa L. [3] were tested. All the investigated substances showed antimalarial activity whereas galloylation generated an increased effect. Pronounced plasmodicidal effects against 3D7 parasite strains were measured for a di-galloylated (4β→6)-dimer (IC50 ˜25µM) and a mono-galloylated trimer with A-type linkage (IC50 ˜15µM).

Acknowledgements: The Ente Cassa di Risparmio di Firenze is gratefully acknowledged for generous financial support.

References: [1] Snow, R.W. et al. (2005) Nature 434: 214. [2] Sannella, A.R. et al. (2007) Biochem Biophys Res Commun 353: 177–181. [3] Anke, J. et al. (2006) 54rd Annual Congress of the Society for Medicinal Plant Research, Helsinki, P 039.