Application of high performance liquid chromatography to the analysis of crude drugs: Separatory determination of saponins of Bupleuri radix.

Abstract

The optimal conditions for conversion of saikosaponins-a (1) and -d (3), the pharmacologically active major saponins of roots of Bupleurum falcatum, into diene-saponins (saikosaponins-b₁ (4) and -b₂ (6)) was investigated. By means of high performance liquid chromatography (HPLC) on an octadecylsilylated silica gel column, complete separation and highly sensitive quantitative analysis of these diene-saponins, which exhibit characteristic ultraviolet maxima, were possible, offering a rapid and selective procedure for the determination of 1 and 3 in commercial samples of Bupleuri radix. Some of the crude drugs on the Japanese market were evaluated by this procedure and it was found that the HPLC pattern of "Chiku-Saiko" imported from Korea was different from those of other crude drugs and cultivated B. falcatum, but similar to that of roots of B. longeradiatum, supporting the morphological comparison of Konoshima et al.