Antimalarial activities and toxicities of three plants used as traditional remedies for malaria in the Democratic Republic of Congo: Croton mubango, Nauclea and Pyrenacantha staudtii

• Published in: Annals of tropical medicine and parasitology 2005-06, Vol.99 (4), p.345-357
• Main Authors: Mesia, G K, Tona, G L, Penge, O, Lusakibanza, M, Nanga, T M, Cimanga, R K, Apers, S, Van Miert, S, Totte, J, Pieters, L, Vlietinck, A J
• Format: Article
• Language: English
• Subjects: Croton; Croton mubango; Plasmodium falciparum; Pyrenacantha staudtii
• ISSN: 0003-4983

The antimalarial activities of crude extracts and 17 fractions from the partition of 80%-methanolic extracts of three plants (the stem bark of Croton mubango, the stem bark of Nauclea pobeguinii and the leaves of Pyrenacantha staudtii) used as antimalarial remedies in the Democratic Republic of Congo were studied both in vitro (against Plasmodium falciparum) and in mice infected with PI. berghei berghei. The toxic effects of dried aqueous extracts of the plants were also investigated, in uninfected mice. The most active crude extracts in vitro, with median inhibitory concentrations (IC sub(50)) of 80% chemosuppression of the parasitaemias by day 4. The aqueous extracts of C. mubango and N. probeguinii produced a slightly lower but still significant inhibition of parasitaemia (60%-80%) whereas that of Py. staudtii only suppressed the day-4 parasitaemias by 37%. The dried aqueous extract of the stem bark of C. mubango showed some signs of toxicity in mice, with median lethal doses (LD sub(50)) of 350 mg/kg in the female mice and 900 mg/kg in the male. The extract significantly increased the serum concentrations of glutamate-oxaloacetate transaminase (GOT) and glutamate-pyruvate transaminase (GPT) in mice of both sexes, but had no effect on the blood levels of creatinine or urea. No significant toxic effect was observed for the dried aqueous extracts of N. pobeguinii and Py. staudtii (LD sub(50) >5 g/kg). Neither of these extracts affected the serum.