Simultaneous separation, identification and activity evaluation of three butyrylcholinesterase inhibitors from Plumula nelumbinis using on-line HPLC-UV coupled with ESI-IT-TOF-MS and BChE biochemical detection

► On-line HPLC-ESI-MS-BChEBCD method was firstly established. ► Enable simultaneously separating, identifying, evaluating activity of BChE inhibitor. ► Liensinine, isoliensinine, and neferine are new-found BChE inhibitors. ► BChE activity of 1 g Plumula nelumbinis is equal to that of 127.88 μmol tacrine. ► Norisoliensinine and 6-hydroxynorisoliensinine were proposed as two new compounds.