Acetylcholinesterase-inhibitory activity of Iranian plants: Combined HPLC/bioassay-guided fractionation, molecular networking and docking strategies for the dereplication of active compounds.

In order to search for discovery of acetylcholinesterase (AChE) inhibitors, as a therapeutic strategy for treatment of the Alzheimer's disease, twenty-five Iranian plants have been evaluated by an in vitro enzymatic Ellman method and molecular docking study. Each plant was successively extracted by n-hexane, ethyl acetate and methanol to obtain a total of 75 extracts. The inhibiting effect of extracts was measured by a colorimetric assay in 96-well microplates. The n-hexane extract of Prangos ferulacea showed the highest AChE inhibitory activity with 75.6% inhibition at a concentration of 50 μg/mL. The chemical composition of this extract was investigated in detail based on a combination of HPLC/bioassay-guided fractionation and molecular networking techniques. The results led to the identification of seventeen compounds, one of them was a fatty acid derivative, two compounds had flavonoid structure and others were furanocoumarin type compounds. In vitro analysis showed that the subfraction F10f was the most potent inhibitor against the activity of AChE with an IC50 value of 25.2 μg/mL and good docking scores of its constituents confirming its high activity.