title: Preparative separation of alkaloids from Nelumbo nucifera leaves by conventional and pH-zone-refining counter-current chromatography.
abstract: Two modes of high-speed counter-current chromatography (HSCCC) were successfully applied to the separation of alkaloids from crude extract of Nelumbo nucifera leaves. The conventional HSCCC separations were performed with a two-phase solvent system composed of tetrachloromethane-CHCl3-methanol-0.1 M HCl at a volume ratio of 1:3:3:2 (v/v/v/v), and 120 mg crude extract could be successfully separated. pH-Zone-refining CCC was performed with a two-phase solvent system composed of petroleum ether (60-90 degrees C)-ethyl acetate-methanol-water (5:5:2:8, v/v/v/v) where triethylamine (10 mM) was added to the upper organic stationary phase as a retainer and hydrochloric acid (5 mM) to the aqueous mobile phase as an eluent. From 4.0 g of the crude extract, 120 mg N-nornuciferine, 1020 mg nuciferine and 96 mg roemerine were obtained in a single run each with a purity of over 98% as determined by HPLC. The structures of the isolated compounds were identified by ESI-MS, 1H NMR and 13C NMR.
authors.affiliation: College of Food Science and Engineering, Shandong Agricultural University, 61 Daizong Street, Taian, Shandong 271018, China.
authors.forename: Zhenjia
authors.initials: Z
authors.lastname: Zheng
authors.forename: Minglin
authors.initials: M
authors.lastname: Wang
authors.forename: Daijie
authors.initials: D
authors.lastname: Wang
authors.forename: Wenjuan
authors.initials: W
authors.lastname: Duan
authors.forename: Xiao
authors.initials: X
authors.lastname: Wang
authors.forename: Chengchao
authors.initials: C
authors.lastname: Zheng
mesh_terms: D000470:Alkaloids / Q000737:chemistry / Q000302:isolation & purification*; D001060:Aporphines / Q000737:chemistry / Q000302:isolation & purification; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D003377:Countercurrent Distribution / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D031653:Nelumbo / Q000737:chemistry*; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods; D018515:Plant Leaves / Q000737:chemistry*
chemical_list: D000470:Alkaloids; D001060:Aporphines; C030169:roemerine; C008692:nuciferine