pH-zone-refining counter-current chromatography of lappaconitine from Aconitum sinomontanum Nakai I. Separation of prepurified extract

pH-Zone-refining counter-current chromatography was applied to the separati on of diterpenoid alkaloids from a crude sample from a crude prepurified sa mple containing lappaconitine at about 90% purity using a multilayer coil p lanet centrifuge. The experiment was performed with a two-phase solvent sys tem composed of methyl tert-butyl ether-tetrahydrofuran-distilled water (2: 2:3, v/v) where triethylamine (10 mM) was added to the upper organic statio nary phase as a retainer and hydrochloric acid (10 mM) to the aqueous mobil e phase as an eluter. The separation of 10.5 g of the sample yielded 9.0 g of lappaconitine at a high purity of over 99% as determined by HPLC. (C) 20 01 Elsevier Science B.V. rights reserved.