Anti-plasmodial Effect of C. limon and C. paradisi extracts on Plasmodium berghei-infected mice

Antiplasmodial effect of Citrus limon and Citrus paradisi extracts on Plasmodium berghei-infected mice was studied. Twenty five albino mice were randomized into five categories of G, L, GL, ACT (positive control) and NC which stand for grape, lemon, grape and lemon combined extracts, artemisinin combined therapy and negative control respectively. The NC group did not receive any intervention. Other treatments were administered orally for 12 days whereas administration of ACT lasted for 3 days. Blood was collected from the tail vein of the mice at a three day interval through venipuncture. Thick blood films were prepared and parasite densities were estimated using standard parasitological techniques. Results were analysed with ANOVA and Duncan multiple range tests. There was no significant difference (p>0.05) between parasite densities of the treatment groups and the negative control at baseline levels. However, as the treatment progressed from day 3 through day 9, there were significant reductions (p<0.05) in parasite densities among treatment groups when compared to the negative control. In this study, extracts of C. limon and C. paradisi in both single and combined strengths have been found to have antiplasmodial properties in mice. ACT possessed the highest antiplasmodial effect while C. limon as a single treatment ranked second in possession of antiplasmodial activity but exhibited increased RBC lysis. In combination, C. limoni and C. paradise extracts showed antiplasmodial activity that is slightly less than that exhibited by the lemon extract alone, but maintained normal RBC morphology whereas C. paradisi extract alone exhibited the lowest level of parasite clearance with atrophied red blood cells. Investigation of the effects of the extracts on liver, kidney and gastrointestinal tissues of mice is recommended before they could be prescribed as antimalaria for other animals and humans.