title: Determining acetylcholinesterase inhibitory activity in plant extracts using a fluorimetric flow assay.
abstract: A fluorometric assay for acetylcholinesterase inhibitory activity was developed in a flow system using the fluorogenic substrate 7-acetoxy-1-methyl quinolinium iodide which is hydrolysed to the highly fluorescent 7-hydroxy-1-methyl quinolinium iodide. The detection limit of galanthamine is 0.5 microM, which is about 20 times more sensitive than in the colorimetric flow assay. In the presence of 30% methanol or of 5% acetonitrile, about 70% of the enzyme activity could still be detected. Various plant extracts have been screened using the described system including bulbs of Galanthus nivalis, Eucharis amazonica (E. x grandiflora), Crinum powelli and Nerine bowdenii (all members of the Amaryllidaceae), which showed strong AchE inhibitory activity.
authors.affiliation: Division of Pharmacognosy, Leiden/Amsterdam Centre for Drug Research, Gorlaeus Laboratories, Leiden University, PO Box 9502, 2300 RA Leiden, The Netherlands.
authors.forename: In Kyung
authors.initials: IK
authors.lastname: Rhee
authors.forename: Natalie
authors.initials: N
authors.lastname: Appels
authors.forename: Teus
authors.initials: T
authors.lastname: Luijendijk
authors.forename: Hubertus
authors.initials: H
authors.lastname: Irth
authors.forename: Robert
authors.initials: R
authors.lastname: Verpoorte
mesh_terms: D000110:Acetylcholinesterase / Q000378:metabolism*; D002800:Cholinesterase Inhibitors / Q000032:analysis*; D005470:Fluorometry / Q000295:instrumentation / Q000379:methods*; D019684:Magnoliopsida / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry*; D018514:Plant Structures / Q000737:chemistry; D012680:Sensitivity and Specificity
chemical_list: D002800:Cholinesterase Inhibitors; D010936:Plant Extracts; D000110:Acetylcholinesterase