Antimalarial Assay, Isolation, and Characterization of Compounds Responsible for Antimalarial Activity in Daniellia oliveri (Rolfe) Hutch. and Dalziel (Caesalpiniaceae)

Abstract

Aim: The research aimed to investigate the antimalarial activity of the plant Daniellia oliveri (Rolfe) Hutch. & Dalziel (Caesalpiniaceae) bark methanol extract. Methodology: The bark dried, powdered bark of Daniellia oliveri was extracted with n-hexane followed by methanol. methanol extract of Daniellia oliveri was tested for antimalarial (curative test) by being tested against Plasmodium berghei in mice at doses of 100, 400, and 600 mg/kg. An acute toxicity study was carried out according to OECD 423 protocol, and phytochemical screening using standard protocols. HPLC-MS was also conducted using Agilent InfinityLab LC/MSD with Eclipse plus C18 5.0 µm 4.6 mm x 250 mm column and data were processed with Agilent Openlab Chemstation software. Results: Preliminary phytochemical screening of the extract revealed the presence of flavonoids, tannins, alkaloids, phenolics, and terpenoids. The methanol extract was found to be safe at doses up to 5000 mg/kg body weight (acute lethal dose, LD50) in mice. There was a significant difference in activity between the non-treated, standard, and extract dosage groups at (p<0.05). The HPLC-MS analysis showed the presence of 56 compounds. Daniella oliveri bark methanol extract has High activity against Plasmodium berghei, an 81.1% reduction in parasitemia at a dose of 600mg/kg body weight, and a Mean survival time of excess 5. Conclusion: Daniellia oliveri is a rich source of phytochemicals and a potential source of antimalarial agent(s).