Antiplasmodial activity and cytotoxicity of ethanol extract of Zea mays root

Abstract

<strong>Objective:</strong><em>Zea mays </em>root decoction that has been traditionally used for the treatment of malaria by various tribes in Nigeria, was evaluated for antimalarial potential against malaria parasites using <em>in vivo</em> and <em>in vitro</em> models.<br /> <strong>Materials and Methods:</strong> The root extract of <em>Zea mays </em>was investigated for antimalarial activity against <em>Plasmodium berghei </em>in mice using rodent malaria models; suppressive, prophylactic and curative tests and <em>in vitro</em> antiplasmodial activity against chloroquine-sensitive (Pf 3D7) and resistant (Pf INDO) strains of <em>Plasmodium falciparum</em> using SYBR green assay method. Median lethal dose and cytotoxic activity against HeLa and HEKS cells were assessed and phytochemical screening was also carried out using standard procedures.<br /> <strong>Results:</strong> The LD₅₀ value of root extract was found to be 474.34 mg/kg. The crude extract (45-135 mg/kg, p.o) showed significant (p<0.05-0.001) antimalarial activity against <em>P. berghei</em> infection in suppressive, prophylactic and curative tests with a prolonged survival time. The crude extract also showed moderate activity against both chloroquine-sensitive (Pf 3D7) and resistant (Pf INDO) strains of <em>P. falciparum</em> with an IC₅₀ value of 71.62±3.38 μg/ml (for Pf 3D7) and 63.76±4.12 μg/ml (for Pf INDO). The crude extract was not cytotoxic to the two cell lines tested with TC₅₀ of >100 μg/ml against both HeLa and HEKS cell lines.<br /> <strong>Conclusion: </strong>These results suggest that the root extract of <em>Zea mays </em>possesses antimalarial activity against both chloroquine-sensitive and resistant malaria and these data justify its use in ethnomedicine to treat malaria infections.