SEPARATION AND PURIFICATION OF TRITERPENE SAPONINS FROM ROOTS OF RADIX PHYTOLACCAE BY HIGH-SPEED COUNTERCURRENT CHROMATOGRAPHY COUPLED WITH EVAPORATIVE LIGHT SCATTERING DETECTION

Abstract

Coupled with evaporative light scattering detection, high-speed countercurrent chromatography was successfully applied for the first time for separation and purification of four triterpene saponins including esculentosides A, B, C, and D from the roots of Radix phytolaccae. The separation was performed with an optimized two-phase solvent system composed of chloroform-methanol-water (4:4:2,v/v), using the lower phase as the mobile phase at a flow rate of 1.5 mL/min. From 150 mg of crude extract, 46.3 mg of esculentoside A, 21.8 mg of esculentoside B, 7.3 mg of esculentoside C, and 13.6 mg of esculentoside D were obtained at purities of 96.7%, 99.2%, 96.5%, and 97.8%, respectively, as determined by HPLC analysis. The structures of the four triterpene saponins were identified by ESI-MS,¹H NMR and ¹³C NMR.

Keywords:

• high-speed countercurrent chromatography
• Radix phytolaccae
• triterpene saponins

ACKNOWLEDGMENTS

The authors thank Ying Liu, Xi Xu, and Wancui Fan of the Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, Northwest University, Xi'an, China for their assistance in ESI-MS experiments.