In vitro anthelmintic potential of Vernonia amygdalina and Secamone africana on gastrointestinal nematodes

In-vitro studies were conducted to determine the anthelmintic activity of ethanolic and water extracts of Vernonia amygdalina and Secamone africana used by agro-pastoralists in semi-arid land Uganda. The plant materials were collected from Nakasongola district and extracted using 70% ethanol and water. Efficacy and potency of crude extracts was determined using extracts’ serial dilutions ranging 4mg/ml to 64mg/ml parallel to serial dilutions of albendazole ranging: 6.25100mg/ml in three replicates. Ascaris suum model was used for the assays. Standard phytochemical methods were used for qualitative phytochemical analysis. The plants’ extracts caused a dose-dependent motility inhibition with highest concentration of both ethanolic and water extracts of V.amygdalina causing 90% inhibition compared with 100% inhibition caused by albendazole. The corresponding median effective doses of ethanolic, water and albendazole were 5.94mg/ml, 13.70mg/ml and 15.12mg/ml respectively and significantly differed (F(2, 53) =257.43, p=0.001). There was a significant difference in motility inhibition in all dose levels (F(5, 53) = 14.01, P = 0.001; R2 = 0.93). Similarly, the water and ethanolic extracts of S.africana caused a 93.3% and 80% motility inhibition with median effective doses of 40.08mg/ml and 25.41mg/ml respectively which also significantly differed (F(2, 53) =183.26, p= 0.001). There was also a highly significant difference in motility inhibition in all dose levels (F(5, 53) = 8.00, P = 0.001; R2 = 0.92). The phytochemical screening revealed presence of tannins, alkaloid, saponins, flavonoids, steroids glycosides, triterpenes, coumarin derivatives, anthocyanocides, anthracenocides, and reducing sugars. In conclusion, V.amygdalina and S.africana are potential sources for novel antihelmintics and the secondary metabolites present justify their ethno-veterinary use.