title: Determination of breviflavone A and B in Epimedium herbs with liquid chromatography-tandem mass spectrometry.
abstract: Two new types of minor flavonoids, breviflavone A and B, have been recently isolated and identified from Epimedium brevicornu in our previous research. Breviflavone B is a novel flavonoid with potent and specific estrogen receptor (ER) bioactivity. Its positional isomer, breviflavone A, is not ER active. Therefore, it is important to determine the two minor components, breviflavone A and B, in Epimedium herbs. In this report, a robust method for measurement of the two breviflavones in Epimedium ethanolic extracts has been developed by using liquid chromatography tandem mass spectrometry via selected-reaction monitoring (m/z 437-->m/z 367 for breviflavone A and m/z 437-->m/z 351 for breviflavone B) under negative electrospray ionization mode. This method has been successfully used to determine the two breviflavones in ethanolic herbal extracts of five major Epimedium species (E. brevicornu, E. koreanum, E. pubescens, E. sagittatum, and E. wushanese) from various sources. The contents of the two breviflavones range from 0.0181 to 0.1791% for breviflavone A and 0.0026 to 0.0252% for breviflavone B in the dried ethanolic extracts of those Epimedium herbal samples.
authors.affiliation: Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Republic of Singapore.
authors.forename: Xin
authors.initials: X
authors.lastname: Hong
authors.forename: Xiaochong
authors.initials: X
authors.lastname: Wang
authors.forename: E L
authors.initials: EL
authors.lastname: Yong
authors.forename: Yinhan
authors.initials: Y
authors.lastname: Gong
mesh_terms: D002851:Chromatography, High Pressure Liquid; D034181:Epimedium / Q000737:chemistry*; D005419:Flavonoids / Q000032:analysis*; D018515:Plant Leaves / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet; D053719:Tandem Mass Spectrometry
chemical_list: D005419:Flavonoids; C542074:breviflavone A