Cholinesterase Inhibitory Activities and In Silico Docking Studies of Blumeatin Isolated from Blumea balsamifera L. DC.

Cholinesterase inhibition provides symptomatic treatment for neurodegenerative diseases such as Alzheimer’s disease. Commercially available drugs on the market mostly target acetylcholinesterase. However, evidence suggests that selective inhibition of butyrylcholinesterase may lead to greater efficacy with fewer side effects and slower disease progression. The aim of this research was to isolate a butyrylcholinesterase-selective inhibitor from Blumea balsamifera L. DC. In vitro cholinesterase assays were used to evaluate the inhibitory activity and mechanism of action of blumeatin. Molecular docking studies were performed to support the BuChE- selectivity of blumeatin. Blumeatin inhibited BuChE in a concentration-dependent manner, with an IC50 of 136.3 ± 12.6 μM and a selectivity ratio of 1.395 for BuChE over AChE. Additionally, the Ki of blumeatin is 10 times lower in BuChE compared to AChE. Molecular docking studies confirmed the selectivity, as revealed by the tighter hydrogen bonding of blumeatin with the BuChE’s active site. Blumeatin acts as a competitive inhibitor and a noncompetitive inhibitor of BuChE and AChE, respectively. With these results, blumeatin could be a potential lead as a drug treatment for AD because of its butyrylcholinesterase selectivity.