ABSTRACT
Zea mays leaf extract and fractions were investigated for antimalarial activity against Plasmodium berghei using a rodent malaria model and in vitro activity against chloroquine-sensitive (Pf 3D7) and -resistant (Pf INDO) strains of P. falciparum using the SYBR green assay method. Median lethal dose (LD50) and cytotoxic activities against HeLa and HEKS cells were also carried out. The most active fraction was analyzed by gas chromatography-mass spectrometry (GCMS). The leaf extract (170–510 mg.kg–1, p.o.), with LD50 of 1,732.05 mg.kg–1, demonstrated antimalarial activity against P. berghei infection in suppressive, prophylactive, and curative tests. The crude extract and the fractions also exerted prominent activity against both chloroquine-sensitive (Pf 3D7) and -resistant (Pf INDO) strains of P. falciparum, with the ethyl acetate fraction exerting the highest activity with IC50 value of 32.31 ± 2.56 μg.mL–1 (Pf 3D7) and 13.60 ± 0.57 μg.mL–1 (Pf INDO). The crude leaf extract and fractions were not cytotoxic to the two cell lines tested, with IC50 of >100 μg.mL–1 against both HeLa and HEKS cell lines.
Acknowledgment
Dr. Jude Okokon is grateful to the International Centre for Genetic Engineering and Biotechnology (ICGEB) for financial support for a postdoctoral fellowship and ICGEB, Delhi, India, for providing research facilities.