Isolation of the acetylcholinesterase inhibitor ungeremine from Nerine bowdenii by preparative HPLC coupled on-line to a flow assay system.
In an attempt to isolate the active compound while detecting acetylcholinesterase inhibitory activity, we applied a fluorometric flow assay system to an on-line coupled preparative HPLC. The MeOH extract of Nerine bowdenii showed a strong inhibitory peak in the on-line assay, and the active compound was isolated by CPC and HPLC. It was identified as ungeremine by analysis of its (1)H-NMR, 2D-NMR, and NOESY spectra. The assignment of the active N. bowdenii constituent was also confirmed by co-TLC, co-HPLC, and co-(1)H-NMR experiments using an authentic sample of synthetic ungeremine. The IC(50) value of ungeremine was 0.35 microM, showing stronger activity than galanthamine (2.2 microM).
Rhee
In Kyung
IK
Division of Pharmacognosy, Section Metabolomics, Institute of Biology, Leiden University, The Netherlands.
Appels
Natalie
N
Hofte
Bertil
B
Karabatak
Bahadir
B
Erkelens
Cornelis
C
Stark
Lucy M
LM
Flippin
Lee A
LA
Verpoorte
Robert
R
D047151:Amaryllidaceae Alkaloids / Q000737:chemistry / Q000302:isolation & purification*; D002800:Cholinesterase Inhibitors / Q000737:chemistry / Q000302:isolation & purification*; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D005470:Fluorometry; D007212:Indolizines / Q000737:chemistry / Q000302:isolation & purification*; D019668:Liliaceae / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D035281:Plant Tubers / Q000737:chemistry
D047151:Amaryllidaceae Alkaloids; D002800:Cholinesterase Inhibitors; D007212:Indolizines; C016175:ungeremine