Preliminary studies on the antiplasmodial potential of aqueous and methanol extracts of eucalyptus camadulensis leaf

ObjectiveThe rising problem of resistance to the classical drugs like chloroquine and the problem of recrudescence of malaria after treatment with artemisinin suggest the need for new antimalaria agents. This project was designed to explore the antiplasmodial potential of Eucalyptus camaldulensis leaf extracts.MethodsThe antiplasmodial potential of the methanol and aqueous extracts of Eucalyptus camadulensis (leaf) were evaluated in a mouse model of malaria. Swiss albino mice were intraperitoneally infected with plasmodium berghei (NK65), a rodent malaria parasite. The level of parasitemia, life span, variation in weight and percentage packed cell volume (% PCV) of infected and treated mice were used to assess the efficacy of extracts. Treatment with the extracts at dose levels of 100, 200 and 400mg/kg body weight commenced 72 hours post infection for the test groups, while a standard antimalarial drug, Artesunate, at a dose of 50mg/kg body weight was administered on the positive control group. The negative control group was left untreated.ResultsAnimals treated with the methanol extract showed a significant decrease in parasitaemia (p < 0.05), and survived for 29 days compared with those treated with the aqueous extract which survived for 19 days with a higher level of parasitemia. However, the control group treated with Artesunate showed a significantly lower parasitaemia (p < 0.05) and survived for 34 days when compared with the groups treated with methanol and aqueous extracts. The level of parasitemia, decrease in weight and %PCV in all the treated groups was significantly lower (P < 0.05) compared with the infected but untreated group (negative control) which survived for only 7 days.ConclusionsThe methanol extract of the leaves of E. camadulensis has an antimalarial potential that could be exploited for the benefit of mankind.