The leaves of Croton joufra have been used as a traditional medicine in Assam (Northeast India) to treat the intestinal helminthic infections. The aim of this study was to establish the in vitro and in vivo anthelmintic efficacy of the leaf extract of this plant on Hymenolepis diminuta, a zoonotic tapeworm. The plant extract was also screened for its chemical constituents. The in vitro anthelmintic efficacy of the plant was evaluated by physical motility test on adult cestodes, following their exposure to 10, 20, 30 mg/ml concentrations of the crude leaf extract, while the in vivo effect was determined based on the eggs per gram (EPG) counts and worm recovery rates, using an experimentally induced model of H. diminuta infections in Wistar rats. The in vitro study results showed a dose-dependent effect on the parasite and the highest concentration of the extract (30 mg/ml) caused mortality of the worms in 1.53 ± 0.12 h as compared to 3.46 ± 0.10 h shown by 1 mg/ml concentration of the reference drug, praziquantel (PZQ). The in vivo results showed that a single 800 mg/kg dose of the extract, given for 3 days, was highly efficacious against adult parasites as it reduced the EPG count and worm burdens of rats by 94.74 and 75 %, respectively. The extract also showed almost similar degree of effects against the larval stage of the parasite. As ascertained by the qualitative screening tests, the leaf extract of C. joufra contains terpenoids, tannins, alkaloids, flavonoids, glycosides and reducing sugar. The overall findings of this study suggest that C. joufra leaf extract possesses significant anthelmintic efficacy and support its traditional anthelmintic claims.
Keywords: Anthelmintic; Anticestodal; Croton joufra; Hymenolepis diminuta; Intestinal helminths; Pharmacology; Soil-transmitted helminths.