Objective To establish a HPLC method for the determination of gallic acid in Radix et Rhizoma Rhei and to study the changes of gallic acid content in Radix et Rhizoma Rhei during processing. Methods HPLC method was used to detect gallic acid content. Diamonsil C18(250 mm?4.6 mm,5?m) column was used,and the mobile phase was a mixed liquid of MeOH -0.01 %H3PO4(10∶90). The column temperature was set up at 30℃,the flow rate was 1 mL?min-1,and the detecting wave-length was 273 nm. Results There were obvious differences of gallic acid content between the crude herbal material and different kinds of processed products of Radix et Rhizoma Rhei. The content of gallic acid was decreased in Radix et Rhizoma Rhei prepared by wine,but was increased in Radix et Rhizoma Rhei prepared by steaming with wine and by stewing with wine,and in charred Radix et Rhizoma Rhei. Conclusion The different processing methods have certain effect on the content of gallic acid in Radix et Rhizoma Rhei.

Objective To determine the triterpenoid content in Loquat leaf by using HPLC method and to explore the feasibility of ursolic acid and oleanolic acid as the quantitative markers for determination of Loquat leaf and its preparations.Methods Two desugaring methods of Loquat leaf extracts were compared.The contents of ursolic acid and oleanolic acid in Loquat leaf as well as preparations were measured based on a system of HPLC,with a Dumas Diamonsil C18 column (250 mm×4.6 mm,5 μm) was used as analytical column.The mobile phase was consisted of acetonitrile-0.1% phosphoric acid (95∶5) with the flow rate of 0.5 mL·min-1.The column temperature was 30 ℃,the injection volume was 10 μL, the detective wavelength was 210 nm.Results Ursolic acid and oleanolic acid were measured in both Loquat leaf and its preparations,and their contents were fairy stable and comparable.Conclusion Ursolic acid and oleanolic acid can be served as quantitative markers for the determination of Loquat leaf and its preparations.