Separation of Flavanone-7-O-glycoside Diastereomers and Analysis in Citrus Juices by Multidimensional Liquid Chromatography Coupled with Mass Spectrometry

Publisher Website
Google Scholar
Abstract
The major flavanone-7-O-glycoside constituents in citrus fruit juices (naringin, hesperidin, neohesperidin, narirutin, and eriocitrin) were separated as diastereomers by multidimensional liquid chromatography. The method consisted of coupling two HPLC columns: a reversed-phase (RP18) column was used for the separation of flavanone glycosides, which were, then, individually switched into a carboxymethylated β-cyclodextrin (β-CD)-based column and resolved as the corresponding stereoisomers. The method was used for the full analysis of flavanone glycosides in fresh hand-squeezed and commercial fruit juices by combining the quantitative estimation with the diastereomeric analysis. Quantitative data were in general consistent with previously reported data in this field. CC-LC isomer analysis was carried out by coupling the β-CD column with a mass spectrometer operated with negative ion electrospray ionization (ESI-MS). The results showed that hesperidin was present in orange juices almost exclusively as the 2S isomer, whereas narirutin had mainly the 2R configuration. In grapefruit juices (2S)-naringin prevailed with the respect to the 2R isomer, whereas the opposite was true for narirutin. Lemon juices contained eriocitrin stereoisomers in equal amount (50% each), but hesperidin was almost exclusively found as the 2S isomer. Significant differences of the diastereomeric ratios were observed between freshly squeezed juices and juices from commercial sources. Keywords: Flavanone-7-O-glycosides; diastereomer separation; multidimensional liquid chromatography; ESI-MS detection; citrus fruit juices

This publication has 21 references indexed in Scilit: