BIOCHEMICAL STUDIES OF SOME PLANT EXTRACTS IN USE AS ANTI-MALARIALS IN WESTERN NIGERIA

Abstract

In order to investigate the antimalarial property of some local medicinal plants namely Asardirachta indica, Morlnda lucida, Alstonia boonei, Enantia ohlorantha and some mixtures of plants used especially in the Western State of Nigeria, experimental malaria, induced in Mice and chicks with Plasmodium berghei and Plasmodium gallinaceum respectively, was treated with the plant extracts prepared as used traditionally using as criteria of oure their effects on (a) the level of parasitemia in the treated animals compared with untreated controls, (b) the body temperature (c) serum total proteins (d) serum protein fractions (e) serum glucose level (f) serum total bilirubin (g) serum enzymes, glutomic pyruvate transaminase (GPT), leuoine amino poptidase (LAP) and alkaline phosphatase. The results of such experiments in mice showed that none of the six plant extracts tried had anti-malarial properties against rodent malaria. In chicks only the water extract of leaves of Morinda lucida at a high a concentration had some suppressive action against this avian malaria but the effect was insignificant compared with the effect of Chloroquine which was used as the standard drug.. In both mice and chicks the extracts had no beneficial effect on the values of some serum biochemical constituents that were studied. Results of an investigation of the extracts of the two most popular plants - Morinda lucida and Asadirachta indica on some hospitalised malaria patients showed no beneficial effect on the patients as evidenced by deteriorating clinical symptoms which improved after administration of chloroquine sulphate. When tried on normal animals, some of the plant extracts had some adverse effects on the animals. Prolonged use of some of them might be toxic to the liver. Since these drugs do not possess antimalarial properties comparable with any of the existing antimalarial drugs, and in view of their toxic effect on the liver, it is puzzling to note their wide spread use as curative agents in peasant communities in Nigeria.