Rapid Profiling of Steviol Glycosides from Stevia rebaudiana using UHPLC/Tandem Mass Spectrometry in a Hybrid Linear Ion Trap Mass Analyzer

摘要

A sensitive and reproducible LC-MS/MS method for quantifying Steviol, Isosteviol and seven other Steviol glycosides in Stevia leaf extracts was developed with analysis times of 8 min/sample with limits of detection of <1 ng/ml for Steviol, 6 ng/ml for Isosteviol and below 15 ng/ml for all Steviol glycosides. These findings represented ways for improvement of LC separation of Steviol glycoside isomers using reversed phase chromatography. Selective ion fragmentation via tandem mass spectrometry which both can improve sensitivity that yields lower limits of detection and quantification. This method improves large scale profiling of Steviol glycosides. Base-line separation of isomers via fine gradient adjustments and column right selection plus minimal in-source fragmentation via optimization of source parameters can lead to discovery of new Steviol glycoside isomers.