In vitro and in vivo anthelmintic study of Sesbania sesban var. bicolor, a traditionally used medicinal plant of Santhal tribe in Assam, India.

The leaf decoction of Sesbania sesban var. bicolor is used traditionally by Santhal tribe of Assam, India, for the treatment of intestinal helminthic infections. This study was conducted to evaluate the in vitro and in vivo anthelmintic efficacy of methanolic extract of S. sesban var. bicolor leaves using Hymenolepis diminuta-rat (cestode) and Syphacia obvelata-mice (nematode) as test parasites and models. Praziquantel (PZQ) and albendazole (ABZ) were used as reference drugs. At the highest concentration of 30 mg/ml of the plant extract, H. diminuta and S. obvelata showed mortality at 0.81 ± 0.01 h and 15.17 ± 0.05 h, respectively. The in vivo results substantiated the in vitro findings, and the extract showed a better cestocidal efficacy in a dose-dependent manner, whereby treatment of rats with 400 mg/kg of the plant extract caused 65.10% reduction in eggs per gram (EPG) of faeces and 56% reduction in worm counts. S. obvelata-infected mice treated at the same dose showed 34.32% and 47.08% reduction in EPG and worm counts at necropsy, respectively. The methanolic extract was subjected to bioassay-guided fractionation using different solvents and the ethyl acetate fraction proved to be the most active. This active fraction was subjected to column chromatography using varying concentrations of hexane:ethyl acetate. Maximum efficacy was observed in 7:3 hexane:ethyl acetate, where H. diminuta and S. obvelata showed mortality at 3.56 ± 0.12 h and 9.21 ± 0.02 h, respectively. This indicates that the isolated fraction contained the active component responsible for its anthelmintic activity, which substantiates the medicinal usage in traditional practice. © Indian Society for Parasitology 2020.