Study on influence of processing methods on chemical constituents in Radix Paeoniae Alba

Objective: The influence of processing methods on chemical constituents in Radix Paeoniae Alba was observed. Method: A HPLC method was used for analyzing the changes of eight major constituents, namely gallic acid, paeoniflorin sulfonate, catechin, paeoniflorin sulfonate, albiflorin, paeoniflorin, benzoic acid, pentagalloylglucose and benzoylpaeoniflorin, with the three processing procedures of decorticating, boiling and fumigating by burning of sulphur. Analysis was performed using a Zorbax SB-C_ 18 column (4.6 mm×250 mm,5 μm) with the mixture of acetonitrile (A) and 0.015% phosphoric acid solution as mobile phase in gradient mode. The detection wavelength was set at 230 nm and the column temperature was at 30 ℃. Result: Except for gallic acid and pentagalloylglucose, the other constituents decreased during procedure of decorticating and boiling. Fumigating by burning of sulphur would produce a new compound, paeoniflorin sulfonate, which was a byproduct from the reaction of paeoniflorin with SO_2. Conclusion:The significant changes were produced in chemical constituents of Radix Paeoniae Alba during three processing procedures . Therefore, the processing of Radix Paeoniae Alba should be strictly controlled and standardized.