Inhibitory effect of corynoline isolated from the aerial parts of Corydalis incisa on the acetylcholinesterase

In the course of screening Korean natural products for acetylcholinesterase (AChE) inhibitory activity, it was found that a methanolic extract of the aerial parts of Corydalis incisa (Papaveraceae) showed significant inhibitory effects on AChE. Corynoline isolated from this plant inhibited AChE activity in a dose-dependent manner, and the IC50 value of corynoline was 30.6 muM. The AChE inhibitory activity of corynoline was reversible and noncompetitive.