title: Determination of free isomeric oleanolic acid and ursolic acid in Pterocephalus hookeri by capillary zone electrophoresis.
abstract: A rapid capillary zone electophoresis (CZE) method for the quantification of two bioactive terpenes in Pterocephalus hookeri was developed. With beta-cyclodextrin as an additive, excellent resolution for these hydrophobic isomers can be obtained in less than 11 min. Linear calibration range for oleanolic acid was between 15.6 and 1000 microg/ml (r=0.9998), for ursolic acid between 31.2 and 1000 microg/ml (r=0.9992). The limits of detection for oleanolic acid and ursolic acid were 3.4 and 3.8 microg/ml, respectively. The contents of the free oleanolic acid and ursolic acid in P. hookeri were determined with recoveries ranging from 95.2 to 106.0%. The contents of oleanolic and ursolic acids were found to be 0.21 mg/g (RSD 5.49%) and 0.53 mg/g (RSD 3.37%), respectively. After hydrolysis by acid, these values were 1.12 mg/g (RSD 3.29%) and 0.43 mg/g (RSD 3.42%).
authors.affiliation: Key laboratory for Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Yang
authors.forename: Yuqin
authors.initials: Y
authors.lastname: Li
authors.forename: Xia
authors.initials: X
authors.lastname: Liu
authors.forename: Shengxiang
authors.initials: S
authors.lastname: Jiang
mesh_terms: D004365:Drugs, Chinese Herbal / Q000032:analysis*; D019075:Electrophoresis, Capillary / Q000295:instrumentation / Q000379:methods*; D015394:Molecular Structure; D009828:Oleanolic Acid / Q000032:analysis* / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D013237:Stereoisomerism; D013997:Time Factors; D014315:Triterpenes / Q000032:analysis* / Q000737:chemistry; D047392:beta-Cyclodextrins / Q000494:pharmacology; D000097245:Ursolic Acid
chemical_list: D004365:Drugs, Chinese Herbal; D009828:Oleanolic Acid; D014315:Triterpenes; D047392:beta-Cyclodextrins; D000097245:Ursolic Acid; C031215:betadex