Marine algal extracts inhibit growth of the human pathogens P. falciparum, T. brucei and L. donovani
Marine macrophytes have been highlighted as resources containing a variety of biologically active compounds and particularly showing in vitro antiprotozoal activities1,2. As a part of a screening program to search new natural antiprotozoal products, we screened 20 seaweed species from the Normandy's coast belonging to Rhodophyta, Pheophyta and Chlorophyta against protozoa responsible for 4 major endemic parasitic diseases in vitro. Thus, brown, red and green seaweeds extracts were screened in vitro against P. falciparum, T. brucei, T. cruzi and L. donovani, respectively responsible of malaria, African trypanosomiasis, Chaga's disease and visceral leishmaniasis. No or weak activity was shown against T. cruzi and L. donovani. In contrast, more than half of the species tested showed good to strong activity against P. falciparum and T. brucei (0.5<IC50<5µg/ml). Interestingly, the active species are brown or red algae, all sharing phyllogenetic origins with P. falciparum. Green algae were inactive. Bio-guided fractionation of the most active extracts (IC50<5µg/ml) is under process.
Acknowledgements: Agence Universitaire de la Francophonie, S. Sritharan.
References: 1. Lin et al. 2010J. Nat. Prod 73:275–8.
2. Afolayan et al. 2009 Phytochemistry 70:597–600.