In vitro and in vivo analysis of the anti-plasmodial activity of ethanol extract of Phyllanthus nivosus W. Bull leaf.

Antimalarial agents are necessary tools in the global malaria eradication agenda and plants used traditionally in the treatment of malaria are indispensable sources of antimalarial compounds. The aim of this study was to evaluate the antiplasmodial potential of Phyllanthus nivosus leaf. In vitro antiplasmodial assay was conducted using Plasmodium falciparum infected erythrocytes incubated at 37 °C in modified RPMI 1640 culture media. The inhibitory effect of the ethanol extract on plasmodium lactate dehydrogenase (pLDH) activity was determined as a measure of antiplasmodial activity. In vivo study was done using mice infected with chloroquine sensitive P. berghei (NK-65 strain). Parasitemia, packed cell volume (PCV), hemoglobin (Hb) and liver lipid peroxidation (MDA) levels were determined after a 4 day treatment. Chloroquine was used as standard drug for both assays. The extract reduced pLDH activity by 39.52, 42.07 and 43.87% at 12, 25 and 50 μg/mL respectively. 100 and 200 mg/kg body weight of extract and 10 mg/kg chloroquine suppressed parasitemia of infected mice by 82.76, 81.11 and 86.87% respectively. Furthermore, the extract significantly reduced (p < 0.05) the elevated MDA level and reversed PCV and Hb levels of infected mice to normal values. Phytochemical screening of the extract revealed the presence of alkaloids, tannins, flavonoids, cardiac glycosides, anthraquinones, steroids and terpenes. Gas chromatography-mass spectrometry (GC-MS) analysis showed the presence of ten compounds, the most abundant of which is Methyl linoleate (35.77%). This study demonstrated that P. nivosus leaf possesses antimalarial potential and contains bioactive compounds that could be beneficial in the development of new antimalarial agents.