Acetylcholinesterase and butyrylcholinesterase inhibitory compounds from Corydalis cava Schweigg. & Kort

Abstract

In the course of screening plants used in Danish folk medicine as memory enhancers, a crude methanolic extract of tubers from Corydalis cava showed significant acetylcholinesterase inhibitory activity in a dose-dependent manner. Activity guided fractionation of the methanolic extract resulted in the isolation of three alkaloids, bulbocapnine (1), corydaline (2) and corydine (3) as active constituents. Bulbocapnine inhibited acetylcholinesterase as well as butyrylcholinesterase in a dose-dependent manner with IC(50) values of 40+/-2 microM and 83+/-3 microM, respectively. Corydaline inhibited acetylcholinesterase in a dose-dependent manner with an IC(50) value of 15+/-3 microM and corydine inhibited butyrylcholinesterase in a dose-dependent manner with an IC(50) value of 52+/-4 microM. Corydaline was considered inactive against butyrylcholinesterase and corydine against acetylcholinesterase, due to IC(50)>100 microM.