Solubilization of Saponins of Bupleuri Radix with Ginseng Saponins: Cooperative Effect of Dammarane Saponins

Abstract

It has been found that the water solubilities of saikosaponins, the active principles of Bupleuri radix, are greatly increased in the presence of ginsenoside-Ro, the glucuronide bisdesmoside of oleanolic acid of Ginseng. No solubilizing effect was observed with the neutral dammarane Saponins of Ginseng. However, the solubilizing effect of ginsenoside-Ro was significantly potentiated in the presence of the dammarane saponins of 20 ( S)-protopanaxadiol. The relationship between the solubilizing effect and the structure of ginsenoside-Ro was also investigated, elucidating the important role of the glucuronide moiety.