title: Large-scale separation of alkaloids from Corydalis decumbens by pH-zone-refining counter-current chromatography.
abstract: pH-zone-refining counter-current chromatography was successfully applied to the separation of alkaloids from a crude extract of Corydalis decumbens (Thunb.) Pers. using a multilayer coil planet centrifuge (CPC). The experiment was performed with a two-phase solvent system composed of methyl tert-butyl ether (MtBE)-acetonitrile-water (2:2:3, v/v) where triethylamine (5-10 mM) was added to the upper organic stationary phase as a retainer and hydrochloric acid (5-10 mM) to the aqueous mobile phase as an eluter. From 3.1 g of the crude extract, 495 mg protopine, 626 mg tetrahydropalmatine and 423 mg bicuculline were obtained each with a purity of over 93% as determined by high performance liquid chromatography. The structures of the isolated compounds were identified by electron ionization mass spectrometry (EI-MS), high-performance liquid chromatography (HPLC)-electrospray ionisation-mass spectrometry (ESI-MS) and 1H NMR.
authors.affiliation: Shandong Analysis and Test Center, Shandong Academy of Sciences, 19 Keyuan Street, Jinan, Shandong 250014, China. wangx@keylab.net
authors.forename: Xiao
authors.initials: X
authors.lastname: Wang
authors.forename: Yanling
authors.initials: Y
authors.lastname: Geng
authors.forename: Fuwei
authors.initials: F
authors.lastname: Li
authors.forename: Xingang
authors.initials: X
authors.lastname: Shi
authors.forename: Jianhua
authors.initials: J
authors.lastname: Liu
mesh_terms: D000097:Acetonitriles; D000470:Alkaloids / Q000302:isolation & purification*; D053119:Benzophenanthridines; D001600:Berberine Alkaloids / Q000302:isolation & purification; D001640:Bicuculline / Q000302:isolation & purification; D002851:Chromatography, High Pressure Liquid; D031311:Corydalis / Q000737:chemistry*; D003377:Countercurrent Distribution / Q000379:methods*; D005021:Ethylamines; D006851:Hydrochloric Acid; D006863:Hydrogen-Ion Concentration; D008738:Methyl Ethers; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D000097:Acetonitriles; D000470:Alkaloids; D053119:Benzophenanthridines; D001600:Berberine Alkaloids; D005021:Ethylamines; D008738:Methyl Ethers; C043243:methyl tert-butyl ether; C014215:tetrahydropalmatine; D006851:Hydrochloric Acid; C009093:protopine; C016162:triethylamine; D001640:Bicuculline; C032159:acetonitrile