Identification of C-glycosyl flavones by high performance liquid chromatography electrospray ionization mass spectrometry and quantification of five main C-glycosyl flavones in Flickingeria fimbriata

Flickingeria fimbriata is commonly applied in China as a traditional Chinese medicine (TCM), however the quality control of it is incomplete. In this work, we aim to identify and quantify the structures of C -glycosyl flavones in F. fimbriata . High performance liquid chromatography-diode array detector (HPLC-DAD) and High performance liquid chromatography–electrospray ionization–multiple stage tandem mass spectrometry (HPLC–ESI–MS n ) methods were combined to identify C -glycosyl flavones and determine their contents. Twenty acylated C -glycosyl flavones and ten non-acylated C -glycosyl flavones were identified for the first time in F. fimbriata on systematic MS n analysis via HPLC–ESI–MS n . The aglycones of all of these compounds were apigenin or chrysoeriol and were acylated with p -coumaric, ferulic, 3,4-dimethoxycinnamic or 3,4,5-trimethoxycinnamic acids. Furthermore, the quantification result suggest that two C -glycosyl flavones (vicenin-I and vicenin-III) with relative high contents were revealed to be more strongly acylated in F. fimbriata . The method is sufficiently precise, accurate, and sensitive for the qualitative and quantitative analysis of C -glycosyl flavones, which is expected to establish a standard for quality control and identification in this plant.