Enzyme inhibition by molluscicidal agents of Bauhinia variegata and Mimusops elengi in the nervous tissue of Lymnaea acuminata

Objective: To evaluate the effect of enzymatic activity in the nervous tissue of snail Lymnaea acuminata (L. acuminata) by Bauhinia variegata (B. variegata) and Mimusops elengi (M. elengi) and their active molluscicidal components quercetin and saponin. Methods: Treatment of sublethal concentration (40% and 80% of 96-h LC50) in vivo of column-purified fraction of B. variegata leaf and M. elengi bark and their molluscicidal agents quercetin and saponin inhibit the acetylcholinesterase (AChE), acid and alkaline phosphatase (ACP and ALP) activities in the nervous tissue of L. acuminata. Results: AChE activity was more inhibited than ACP and ALP in snail exposed to column- purified fraction of M. elengi bark and saponin. Among all the treatments the highest inhibition in AChE activity (27.77% ) was noted in snail L. acuminata exposed to 80% of 96-h LC50 of saponin at 96-h exposure period. Conclusions: It can be concluded from the present study that inhibition of AChE, ACP and ALP by B. variegata leaf (quercetin) and M. elengi bark (saponin) in snail L. acuminata could be the cause of snail mortality.