Determination of six saikosaponins in Bupleurum chinense DC. samples collected from different producing areas at different harvest time with different processing methods

An HPLC method was established for the simultaneous determination of saikosaponin a, b₂, c, d, e, f of Bupleurum chinense DC. in order to study the content difference of saikosaponins in different producing areas, different harvest time and different processed products of Bupleurum chinense DC. The Agela Venusil MP C₁₈ (4.6 mm×250 mm, 5 μm) column was used with a gradient elution of acetonitrile-water at the wavelength of 210 and 254 nm with the flow rate of 1.0 mL·min^-1 and the column temperature at 30℃. Based on the content of six kinds of saikosaponins, the differences of saikosaponins in four producing areas, eight harvest periods and 11 processing methods of Bupleurum chinense DC. were systematically studied. The results showed that the content of saikosaponins in Bupleurum chinense DC. was higher in May and August of Liaoning, Shaanxi and Gansu, but only in August from Shanxi in the four producing areas. The content of saikosaponins in 11 processed products was as follows:raw product > bran-stir-fried product > stir-fried product > wine-moistened product > turtle blood-stir-fried product > bran-wine-stir-fried product > wine-stir-fried product > vinegar-moistened product > turtle blood-wine-stir-fried product > vinegar-stir-fried product > honey-stir-fried product > honeymoistened product.