Quantitative Assay of Ursolic Acid and Oleanolic Acid in Siweixiaofu Ethanol-Extracts

Objective:To establish a method for determination of the contents of Ursolic Acid and Oleanolic Acid in Siweixiaofu ethanol-reflux extraction.Methods:Medicinal materials of Siweixiaofu Prescription were double extracted with 0,10,20,40,60,80%ethanol solution(500mL,300mL)respectively.The determination of ethanol-extracts were carried out by RP-HPLC with a Hanbang Lichrospher C18 column at 20℃ and detected at 215nm,using 0.1% phosphoric acid together with acetonitrile(25:75) as the mobile phase(pH7.5) at a flow rate of 1.0 mL·min-1.Results:The calibration curves of Oleanolic Acid and Ursolic Acid had excellent linearity between the range of 1.54～308.00μg·mL-1 and 6.54～1308.00μg·mL-1 respectively.Their average recoveries were 99.63%～111.54%.The extraction rates of Ursolic Acid and Oleanolic Acid were directly proportional to the ethanol concentration.Conclusion:The method is sensitive,convenient and accurate,and is suitable for the simultaneous determination of Ursolic Acid and Oleanolic Acid in Siweixiaofu Prescription.