title: Simultaneous determination of three flavonoid aglycones in Elsholtzia blanda by adopting orthogonal test and high-performance liquid chromatography.
abstract: A new HCl hydrolysis/HPLC method, by adopting L9(34) orthogonal test to optimize hydrolysis condition, has been developed for simultaneous determination of three flavonoid aglycones in Elsholtzia blanda benth. The HCl concentration, methanol concentration, hydrolysis temperature, hydrolysis time are taking as four inspecting foctors, and the contents of luteolin, apigenin, and 5-hydroxy-6,7-dimethoxyflavone in hydrolytic solution are used as the evaluation indexes. Agilent Zorbax SB-C18 is used as analytical column. The mobile phase is a mixture of methanol-0.2% phosphoric acid (70:30, v/v), and UV detector is set at 350 nm. The flow rate is 1.0 mL/min, the temperature of column is maintained at 30 degrees C. The optimal hydrolysis conditions are 3.0M HCl, 70% methanol, 85 degrees C hydrolytic temperature and 3 h hydrolytic time. Standard curves are linear over the concentration range 8.54-85.4 microg/mL, 1.2-12 microg/mL, 9.2-92 microg/mL, and their average recoveries are 96.8%, 98.0%, and 100.5% for luteolin, apigenin, 5-hydroxy-6, 7-dimethoxyflavone, respectively. Thus, the optimum hydrolysis condition is relatively gentle, and the HPLC method is proved to be simple, accurate, and sensitive, so it will be able be applied to quality control of medicinal plant of Elsholtzia blanda.
authors.affiliation: College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310031, PR China.
authors.forename: Juan-Hua
authors.initials: JH
authors.lastname: Xu
authors.forename: Yi-Gang
authors.initials: YG
authors.lastname: Lai
authors.forename: Hui-Di
authors.initials: HD
authors.lastname: Jiang
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhao
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005419:Flavonoids / Q000032:analysis*; D019686:Lamiaceae / Q000737:chemistry*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D005419:Flavonoids