Abstract

The study investigated the activity of saponin from ethanolic extract of Erythrophleum suaveolens stem bark against freshwater snail, Lanistes lybicus. The crude saponin (4 g) was separated by silica gel using gradient elution with dichloromethane in methanol (100:0 to 0:100) followed by thin layer chromatography using precoated silica gel 60 F₂₅₄. Fractionated saponins(90:10, 80:20 and 70:30) were employed for snail toxicity using fresh water snails, L. lybicus.The biochemical changes were evaluated in haemolymph, muscle, intestine and hepatopancreas of fresh water snails exposed to sub-lethal dose of fractionated saponins. Elevation of activities of acid and alkaline phosphatase in the intestine and hepatopancreas, haemolymph and total protein level were observed. The activity of acetylcholinesterase was inhibited in the haemolymph, muscle, hepatopancreas and intestine of the snails. The activity of saponin was observed to be dose dependent as mortality increased with relative increase in the saponin concentrations. The study provides considerable scope in exploiting local indigenous plant resources for control of fresh water snails and monitor water pollution.

Key words: Erythrophleum suaveolens, saponin, molluscicidal activity, Lanistes lybicus,pollution, hepatopancreas