Herbal extract, rich with natural compounds, has been used for medicinal purpose such as treating neurological disorders such as cognitive defection for a long period of time, often without significant adverse effects. We compared AChE and BuChE – inhibition effect of total extracts and fractions of Huperzia serrata (Thunb.) Trevis. with alcaloid-rich extract. Our samples were subjected under supersonic extraction with ethanol 50o as solvent and fractionally extracted with n-hexane, EtOAc and n-butanol, respectively; alcaloid-rich extract was collected simutaneously. Ellman’s method was used to assay AChE and BuChE inhibition activity. Results: Alcaloid-rich extraction proved to be the superior AChE inhibiting agent, its activity nearly 6 fold of the most active Huperzia serrata extraction with IC50 value of 7.93 (5.43-10.98) µg/ml. While the fractions as well as the total extract did not provide any BuChE inhibition activity, alcaloid-rich extract showed weak ability (IC50 at 76.67 (64.78 – 91.84) µg/ml). Overall, the superior enzyme inhibition effect of alcaloid-rich extract might open a new approach in preventing and treating neurological disorders such as alzheimer’s.
 Keywords
 Huperzia serrata (Thunb.) Trevis, alcaloid, Acetylcholinesrerase inhibitors (AChE); butyrylcholinesterase (BuChE), Alzheimer.
 References
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