Antiplasmodial activity of extracts from seven medicinal plants used in malaria treatment in Cameroon.
OBJECTIVE
In a search for new plant-derived biologically active compounds against malaria parasites, we have carried out an ethnopharmacological study to evaluate the susceptibility of cultured Plasmodium falciparum to extracts and fractions from seven Cameroonian medicinal plants used in malaria treatment. We have also explored the inhibition of the Plasmodium falciparum cysteine protease Falcipain-2.


METHODS
Plant materials were extracted by maceration in organic solvents, and subsequently partitioned or fractionated to afford test fractions. The susceptibility of erythrocytes and the W2 strain of Plasmodium falciparum to plant extracts was evaluated in culture. In addition, the ability of annonaceous extracts to inhibit recombinant cysteine protease Falcipain-2 was also assessed.


CONCLUSIONS
The extracts showed no toxicity against erythrocytes. The majority of plant extracts were highly active against Plasmodium falciparumin vitro, with IC(50) values lower than 5 microg/ml. Annonaceous extracts (acetogenin-rich fractions and interface precipitates) exhibited the highest potency. Some of these extracts exhibited modest inhibition of Falcipain-2.


CONCLUSIONS
These results support continued investigation of components of traditional medicines as potential new antimalarial agents.
Laboratory of Phytobiochemistry and Medicinal Plants Study, Faculty of Science, University of Yaoundé I, P.O. Box 812, Yaoundé, Cameroon. ffefe@yahoo.com
Fabrice Fekam
FF
Boyom
Eugénie Madiesse
EM
Kemgne
Roselyne
R
Tepongning
Vincent
V
Ngouana
Wilfred Fon
WF
Mbacham
Etienne
E
Tsamo
Paul Henri Amvam
PH
Zollo
Jiri
J
Gut
Philip J
PJ
Rosenthal
D000818:Animals; D029061:Annonaceae; D000962:Antimalarials / Q000494:pharmacology*; D002163:Cameroon; D003546:Cysteine Endopeptidases / Q000378:metabolism; D004912:Erythrocytes / Q000187:drug effects; D020834:Ethnopharmacology; D019665:Euphorbiaceae; D020128:Inhibitory Concentration 50; D019684:Magnoliopsida; D016778:Malaria, Falciparum / Q000188:drug therapy*; D016488:Medicine, African Traditional; D029586:Moraceae; D021261:Parasitic Sensitivity Tests; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology*; D010946:Plants, Medicinal; D010963:Plasmodium falciparum / Q000187:drug effects*
D000962:Antimalarials; D010936:Plant Extracts; D003546:Cysteine Endopeptidases; C416224:falcipain 2