Determination of Acetylcholinesterase Inhibitory Activity
using Microplate Assay
AChE activity was measured using a modified 96-well
microplate assay [11] based on Ellman’s method [21]. The
enzyme hydrolyses the substrate acetylthiocholine resulting in the
product thiocholine which reacts with Ellman’s reagent (DTNB) to
produce 2-nitrobenzoate-5-mercaptothiocholine and 5-thio-2-nitrobenzoate
which can be detected at 412 nm. 50 mM Tris–HCl
pH 8.0 was used as a buffer throughout the experiment unless
otherwise stated. AChE used in the assay was from electric eel
(type VI-S lyophilized powder, 518 U/mg solid, 844 U/mg