Screening of Inhibiting-cholinesterase Active Fractions from Forsythia Suspensa Leaves

OBJECTIVE To screen the inhibiting-cholinesterase active fractions from Forsythia suspensa leaves.METHODS The crude extract of Forsythia suspensa leaves was prepared by heating reflux method,and then the macroporous resin with ethanol solution of different concentration gradient was used to prepare five kinds of separated parts.The main components in crude extract and separated parts were identified by HPLC.Ellman method was used to study the inhibitory effects on cholinesterase.RESULTS The inhibition effect of the crude extract from Forsythia suspensa leaves on acetylcholinesterase (AChE) was better than that of butyrylcholinesterase (BChE).The separated part in 20% ethanol showed the best ability to inhibit AChE activity.Phillyrin and phillygenin promoted the activity of AChE to a certain extent,while forsythoside E and forsythoside I inhibited the activity of AChE.CONCLUSION The inhibitory effects of separated parts of Forsythia suspensa leaves on cholinesterase was related to the different effects of its main components on AChE activity.