Potential antimalarial activity of Coccinia barteri leaf extract and solvent fractions against Plasmodium berghei infected mice

Coccinia barteri (Hook. F.) is traditional used in Southeast of Nigeria in management of fever. This study aimed to evaluate the antimalarial activities of hydro-methanol crude extract and solvent fractions of Coccinia barteri leaf.

Two animal models employed for the study were, 4-day suppressive and curative assays against chloroquine sensitive Plasmodium berghei NK65. Level of parasitaemia, mean survival time (MST), anal temperature and weight loss were measured to assess antimalarial efficacy of the extract/fractions. Chloroquine (10 mg kg^-1) was used as positive control. Chemo-profile of extract was evaluated using GC-MS, HPLC techniques and standard phytochemical analysis. Preliminary toxicity test was done using modified Lorke's method.

The crude extract (100-400 mg kg-¹) and solvent fractions (20-80 mg kg-¹) demonstrated antimalarial activity in both models compared to controls. Semi purified fractions of the extract produced stronger percentage chemosuppression and inhibition of parasite. The % inhibition of the fractions, hexane, chloroform, ethyl acetate and aqueous at 80 mg kg^-1 were 96.0 0, 95.29, 89.86 and 96.00% respectively on day 8 (D₈). While on D₁₄, 100% parasite clearance, indicating cure was obtained for hexane, chloroform and aqueous fraction treatment groups, no death occurred in these groups. Ethyl acetate fraction treated groups lived longer but were not fully protected. Some marker compounds were identified.

These results support the use of C. barteri as malaria remedy and potential source of antimalarial templates. Long acting parasitaemia reduction effect indicates its possible combination potential in poly-herbal combination therapy.