Analysis of saponins in extract of Panax ginseng and Panax quinquofolium by liquid chromatography-electrospray ionization mass spectrometry

A Liquid chromatography-electrospray ionizaiton mass spectrometry ( LC-ESI-MS) method was developed for the identification and differentiation of ginsenosides in crude extracts from Panax ginseng and Panax quinquofolium L. The [ M - H] - ions of ginsenosides were observed in the negative mode, from which the molecular weights were obtained. The collision induced dissociation (CID) data of the [ M - H] - ions provide detailed structural information of the ginsenosides. By performing CID experiments for the peaks 3 ( ginsenoside Rf) and 8 ( Pseudoginsenoside F11), these two ginsenosides had different CID behavior, and therefore the assignment of the structure for these two isomers was straightforward. The experimental results indicate that P. ginseng and P. quinquofolium can be differentiated rapidly and easily by the LC-ESI-MS experiment.