Kinetics and molecular docking of vasicine from Adhatoda vasica: An acetylcholinesterase inhibitor for Alzheimer's disease

• Four known alkaloids were isolated from Adhatoda vasica.
• Vasicine was the most potent AChE inhibitor among the tested compounds.
• Vasicine was found to be a reversible competitive inhibitor of AChE.
• Docking study revealed similarity of vasicine to tacrine in binding to AChE.

The alcoholic extract of Adhatoda vasica showed strong and reversible inhibition of the enzyme acetyl cholinesterase (AChE) with an IC50 = 294 μg/mL. Phytochemical study of the total alcoholic extract of A. vasica yielded four known compounds vasicine, vasicinone, vasicole and anisotine. Vasicine reversibly and competitively inhibited AChE with ki value 11.24 μM. On the other hand, rest of isolated alkaloids showed no/or weak inhibitory effect on AChE. Vasicine showed binding similarity to both galantamine and tacrine in the catalytic site. The obtained results support the multi-pharmacological properties of vasicine, which can be considered as a promising inhibitor for acetyl cholinesterase where it can be used directly or indirectly for the development of efficient anti-Alzheimer drug.