The processing of Panax notoginseng and the transformation of its saponin components

Notoginseng, the root of Panax notoginseng (Burk.) F. H. Chen (Araliaceae), a famous traditional Chinese medicine, has been used in both raw and processed forms due to their different therapeutic functions. In this study, HPLC analyses on saponin composition of processed notoginseng were conducted, which revealed that, during the steaming process, the five main saponin constituents (ginsenosides Rg1, Rb1, Rd, and Re, and notoginsenoside R1) in raw notoginseng decreased gradually and some other new saponins were formed. Among these, eight newly converted ginsenosides were identified as 20(S)-Rh1, 20(R)-Rh1, Rk3, Rh4, 20(S)-Rg3, 20(R)-Rg3, Rk1 and Rg5. Different processing methods, including steaming and baking, were studied, along with the correlative dynamic curves of the transformation of saponins. The results indicated that the moisture content and temperature were the determinant effecting factors in the preparing process, and water content was necessary and high temperature was helpful for saponin transformation.