Antiplasmodial Activities of Parkia Biglobosa Leaves: In Vivo and In Vitro Studies

Abstract

The wide spread resistance of malaria parasites to conventional anti-malarials have stimulated the search for new drug entities especially those with new modes of action. The efficacy of the preparations of Parkia biglobosa leaves for the treatment of malaria have been widely acclaimed by the Hausa communities of northern Nigeria, thus the need to authenticate this claims as a critical step in the search for a new anti-malarial. The antiplasmodial activity of P. biglobosa was evaluated in vivo and in vitro against Plasmodium berghei berghei and clinical isolates of Plasmodium falciparum respectively. In the in vivo study, effects of graded doses of the extract were evaluated in mice infected with P. berghei berghei, while in the in vitro test the inhibitory effects of graded concentrations of the extract (3.125 to 100 μg/ml) on P. falciparum was evaluated. The oral median lethal dose (LD50) in mice and preliminary phytochemical screening were also evaluated. There was a dose dependent inhibition of parasitaemia in the in vivo antiplasmodial tests, with maximum effect at 600 mg/kg. The in vitro screening demonstrated a weak and concentration-dependent activity (56.23μg/ml > IC50 > 50μg/ml) of the extract against P. falciparum. The LD50 in mice was estimated to be greater than 5000 mg/kg and the phytochemical analysis revealed the presence of flavonoids, tannins, terpenes, saponins, cardiac glycosides, alkaloids and reducing sugars. The leaf extract of P. biglobosa contains biologically active principles that are relevant in the treatment of malaria, thus supporting further studies of its active components.