Abstract
Anthelmintic resistance to commonly used chemotherapeutic drugs is on the increase and alternatives are been explored, and medicinal plants have shown promised as probable alternatives to orthodox drugs. This study was conducted to investigate the in-vitro anthelminthic effects of crude ethanolic and aqueous extracts of Vernonia amygdalina leaf on earthworms (Pheritima posthuma). The leaves were collected from the University of Maiduguri campus, air dried, ground into powder using pestle and mortar and extracted. Four graded concentrations (1.25, 2.5, 5.0 and 10.0 mg/mL) of the crude extract for each solvent were prepared and evaluated for the in-vitro anthelmintic effects. The number of dead and alive earth worms were counted and recorded after 60 minutes and repeated after 120 minutes. The results indicated that there was an increasing mortality with increasing concentration of the ethanolic extract with regards to percentage dead in number of earthworms exposed for 60 minutes with 15% at 1.25mg/mL and 95% at 10mg/mL with a mean±SD of 0.75±0.5 and 4.75±0.5 respectively(p<0.05). After 120 minutes post immersion, the mortality pattern fn the earthworms followed a similar trend with 35% at 1.25mg/mL and 100% at 10mg/mL with a mean±SD of 1.75±0.5 and 5.0±00 respectively (p<0.05). Similarly, the use of the aqueous extract exhibited similar trend. Anthelmintic activity was higher in the exposed earthworms after 120 minutes compared with 60 minutes post immersion across the different treatment groups and both extract concentrations of 10 mg/mL had a 100% death similar to the positive control (Albendazole, 40 mg/mL). In conclusion, anthelmintic activity of the ethanolic and aqueous fractions of V. amygdalina leaf was best observed after 120 minutes of exposure, with increasing activity as the concentration increases with peak action at 10.0 mg/mL