In vivo Antiplasmodial Activity of Ethanolic Leaf Extract of Tithonia diversifolia (Hemsl.) A. Gray against Plasmodium berghei Nk65 in Infected Swiss Albino Mice

Antiplasmodial activity of the ethanolic leaf extract of Tithonia diversifolia was studied in Swiss albino mice infected with Plasmodium berghei (NK65). The study was carried out at the Department of Microbiology, Federal University of Technology, Akure, Nigeria between April and December, 2015. Qualitative phytochemical screening was carried out using standard procedure. Thirty experimental mice (average weight of 18-22 g) were divided into six groups (five mice per group). Groups 1, 2 and 3 were infected with P. berghei and treated with 0.2 ml of 200, 400 and 600 mg/kg body weight of T. diversifolia extract respectively. Group 4 (positive control) was infected with P. berghei and treated with 0.2 ml of 5 mg/kg body weight of chloroquine. Group 5 (negative control) was infected with P. berghei and treated with 0.2 ml of normal saline and group 6 (normal control) was not infected but administered with 0.2 ml of normal saline. Qualitative phytochemical screening revealed the presence of saponin, alkaloid, flavonoid, tannin and cardiac glycoside while quantitative screening revealed the presence of tannins (0.39 mg/100 g), flavonoids (0.87 mg/ 100 g), cardiac glycosides (1.19 mg / 100 g), alkaloids (1.23 mg / 100 g) and saponins (1.37 mg / 100 g). Suppressive test shows that leaf extract exerted significant (P<.05) dose-dependent reduction against the parasite. Chemo-suppression of 60.02%, 63.45% and 92.0% were respectively observed in mice treated with 0.2 ml of 200 mg/kg, 400 mg/kg and 600 mg/kg body weight dosage in groups 1, 2 and 3. Group 4 (positive control) and group 5 (negative control) had 100% and 0.0% chemo-suppression respectively. In conclusion, the ethanolic leaf extract of T. diversifolia at 600 mg/kg significantly suppressed the parasitaemia in the infected experimental mice.