Study on Saikosaponin A and D in a Chinese Traditional Medicine by LC/MS.

To study Saikosaponins in a Chinese traditional compound medicine by LC/MS. Saikosaponin A and D, which were the bioactive components of Bupleurum falcatum L., were not found in the medicine. And three isomeric compounds of Saikosaponin A and D were detected instead. Saikosaponin A and D were found have turned into two other isomers after treated by acid water, but keep unchanged when treated by neutral water. Two of the isomeric compounds which found in the Compound medicine were determined as Saikosaponin B1 and B2 . This work is helpful for quality control of the medicine and also is useful for supervising the procedures of manufacture.