In Vitro Antiplasmodial Activity And Phytochemicals Screening Of Ethnomedicinal Plants Used To Treat Malaria Associated Symptoms

Abstract

Malaria is a major health concern in Sub Saharan Africa and there are few effective treatment options. Namibia has diverse flora with potent antimalarial phytochemicals and high ethnomedicinal plants uses. This study investigated the phytochemical and in vitro antiplasmodial activity of ten ethnomedicinal plants namely: Baikea plurijuga, Cyphostemma spp, Guibourtia coleosperma, Mundulea sericea, Neptunia oleracea, Diospyros mespiliformis, Acrotome inflata, Oxygonum dregeanum, Ziziphus mucronata and Vangueria infausta. Crude methanol extracts from the ten ethno medicinal plants were screened for major classes of antiplasmodial phytochemical compounds i.e., terpenoids, alkaloids, flavonoids, anthraquinones and coumarins using thin layer chromatography (TLC). Total alkaloids and phenolics content of the ten crude methanol plant extracts were quantified spectrophotometrically. Based on the outcomes of phytochemical screen test, M. sericea, D. mespiliformis and Cyphostemma spp were selected for in vitro antiplasmodial microscopy assay of the crude methanol and aqueous extracts. The assay was done at 1% parasitaemia and 2% hematocrit in 96 wells plates for 24 and 48 hours, against P. falciparum 3D7A (chloroquine sensitive and sulfadoxine resistant strain). Coartem was used as a positive control while 0.5% DMSO in RPMI 1640 medium was used as negative control. Furthermore, Cyphostemma spp (whole plant) and D. mespiliformis (leaf and root) were fractionated through Sephadex LH20 column eluted with methanol/DCM (1:1) and n- hexane/ethyl acetate (8:2) for the first and second round respectively. In vitro antiplasmodial assays and phytochemical screening of fractions were carried out at each round.