Quantification and separation of protopanaxatriol and protopanaxadiol type saponins from Panax notoginseng with macroporous resins

Abstract

20( S)-protopanaxatriol saponins (PTS) and 20( S)-protopanaxadiol saponins (PDS) are known as two groups of major ingredients in the root of Panax notoginseng and possess various pharmacological effects. In the present study, a simple method for preparative separation of PTS and PDS from P. notoginseng with macroporous resins was established. The adsorption characteristics of PTS and PDS on four types of macroporous resins, including D-101, DA-201, DM-301 and DS-401, have been compared. Among them, DS-401 resin showed the best separation behaviors. The equilibrium absorption data of PTS and PDS on DS-401 resin at 25 oC was fitted to the Freundlich isotherm. Dynamic adsorption and desorption tests have been performed in glass column packed with DS-401 resin for optimizing the process parameters. Due to different adsorption force to resin, the PTS and PDS were successfully separated with 30% and 80% (v/v) aqueous ethanol solutions, respectively. Based on the conditions optimized above, large-scale preparation of PTS and PDS from P. notoginseng was also carried out. The contents of PTS and PDS were increased from 22.5% and 16.4% in the PLE extract of the root of P. notoginseng to 88.2% and 92.6% in the final products with the recoveries of 80.2% and 82.3%, respectively.