LARGE-SCALE SEPARATION OF STRYCHNINE AND BRUCINE FROM STRYCHNOS NUX-VOMICA L. BY pH-ZONE-REFINING COUNTER-CURRENT CHROMATOGRAPHY

Abstract

Preparative separation of strychnine and brucine from a crude extract of Strychnos nuxvomica L. has been successfully performed for the first time using pH-zone- refining counter-current chromatography. The experiment was performed with a two-phase solvent system composed of n-hexane–ethyl acetate–i-propanol–water (1: 3: 1.5: 4.5, v/v) where triethylamine (10 mM) was added to the upper stationary phase as a retainer and hydrochloric acid (5 mM) was added to the mobile phase as an eluter. From 1.5 g of the crude extract, 176 mg strychnine, and 480 mg brucine were obtained in a single run. The purities of these compounds were 95.1% and 97.0%, respectively, as determined by HPLC. The structures of the isolated compounds were confirmed by electron ionization-mass spectrometer (EI-MS) and ¹H NMR.

Keywords:

• brucine
• pH-zone-refining counter-current chromatography
• preparative chromatography
• strychnos nux-vomica L
• strychnine

ACKNOWLEDGMENT

Financial supports from the Natural Science Foundation of China (20872083), the Key Science and Technology Program of Shandong Province (2010GSF10287), the Key Science and Technology Program of Jinan (201004010), and the Basic Research Program of Institute of Chinese Material Medical, CACMS (ZZ20090107) are gratefully acknowledged.