ANTHELMINTIC EFFICACY OF FLEMINGIA-VESTITA (FABACEAE) - GENISTEIN-INDUCED ALTERATIONS IN THE ESTERASE-ACTIVITY IN THE CESTODE, RAILLIETINA-ECHINOBOTHRIDA

To ascertain the anthelmintic efficacy of Flemingia vestita tan indige nous leguminous plant of Meghalaya, having putative anthelmintic usage ), its crude root-tuber peel extract and active chemical principle, ge nistein, were tested in vitro with reference to esterase activity in t he fowl tapeworm, Raillietina echinobothrida. With the localization of non-specific esterases(NSE) and cholinesterase (ChE), the organizatio n of the cholinergic components of the nervous system in tote could be visualized in the cestode. The specific ChE in the parasite is acetyl cholinesterase (AChE). Both NSE and ChE were found in close associatio n with the central and peripheral nervous components, besides being pr esent in the tegument and muscular parts of the terminal male genitali a. The whole tissue homogenate of the parasite also showed a high AChE activity. After exposure to the crude peel extract (50 mg/ml of the i ncubation medium) and to genistein (0.5 mg/ml), a pronounced decline i n the visible stain intensity in the cholinergic components of the ner vous system and in the tegument was noticeable, indicating extremely r educed activity of NSE and ChE in these sites. The total AChE activity was also reduced to 49.07% and 56.77%, following treatment with the p eel extract and genistein, respectively. The reference drug, praziquan tel (0.01 mg/ml) also caused reduction in the enzyme activity, somewha t at par with the genistein treatment. Genistein appears to have a tra nstegumental mode of action. Alteration in the AChE activity points to wards acetylcholine, an inhibitory neurotransmitter in cestodes, as th e potential: target of action.