Screening for acetylcholinesterase inhibitors from Amaryllidaceae using silica gel thin-layer chromatography in combination with bioactivity staining

• Published in: Journal of Chromatography A Vol. 915; no. 1; pp. 217 - 223
• Main Authors: Rhee, In Kyung, van de Meent, Michiel, Ingkaninan, Kornkanok, Verpoorte, Robert
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 27.04.2001; Elsevier
• Subjects: Acetylcholinesterase - drug effects; Analytical, structural and metabolic biochemistry; Biological and medical sciences; Cholinesterase Inhibitors - analysis; Cholinesterase Inhibitors - isolation & purification; Cholinesterase Inhibitors - pharmacology; Chromatography, Thin Layer - methods; Dithiobis-(nitrobenzoic acid); Enzyme inhibitors; Enzymes and enzyme inhibitors; Fundamental and applied biological sciences. Psychology; General pharmacology; Hydrolases; Magnoliopsida - chemistry; Medical sciences; Pharmacognosy. Homeopathy. Health food; Pharmacology. Drug treatments; Sensitivity and Specificity; Silica Gel; Silicon Dioxide; Enzyme inhibitors; Dithiobis-(nitrobenzoic acid); Amaryllidaceae; Bioactivity staining; Monocotyledones; Chemical analysis; Microtiter plate; Esterases; Acetylcholinesterase; Solvent extraction; Screening test; Medicinal plant; Separation method; Sample preparation; Angiospermae; Qualitative analysis; Anticholinesterase agent; Enzyme; Pharmacognosy; Enzyme inhibitor; Biological activity; Carboxylic ester hydrolases; Thin layer chromatography; Ultraviolet detector; Bulb; Plant origin; Hydrolases; Isolation; Spermatophyta
• ISSN: 0021-9673
• DOI: 10.1016/S0021-9673(01)00624-0

Thin-layer chromatography (TLC) was used to screen for acetylcholinesterase inhibitors from Amaryllidaceae extracts. The TLC plate was developed and then stained using Ellman’s reagent, 5,5′-dithiobis-(2-nitrobenzoic acid), to detect acetylcholinesterase activity. The advantages of this TLC assay method were that we could dereplicate the known inhibitor galanthamine, widely occurring in Amaryllidaceae, at an early stage of the isolation procedure. Moreover, there is no disturbance from sample dissolving solvents as in the microplate assay, and it is a very simple method. The detection limits were 10–200 ng for several known acetylcholinesterase inhibitors tested, and it is thus more sensitive than UV or Dragendorff’s reagent detection. Also the minimal detectable amount for an acetylcholinesterase inhibitor tested was much less than that needed for the microplate assay. We screened 15 Amaryllidaceae extracts using this TLC method, and chose candidates for acetylcholinesterase inhibitor isolation.