Analysis of Limonoid Glucosides from Citrus by Electrospray Ionization Liquid Chromatography−Mass Spectrometry

Abstract
An electrospray ionization liquid chromatography−mass spectrometry (ESI-LC-MS) method for the detection and quantitation of limonoid glucosides has been developed. Negative ions [M − H+]- characteristic of six limonoid glucosides can be detected and quantified from selected ion monitoring chromatograms using carminic acid as an internal standard. The described method has been applied to the analysis of limonoid glucoside content in various liquid and solid Citrus spp. samples as well as complex mixtures of partially purified limonoid glucosides. Rapid and sensitive qualitative screening of samples for limonoid glucosides can also be accomplished with slight modifications of the method. Keywords: Limonoid glucoside; limonin 17β-d-glucopyranoside; electrospray ionization; liquid chromatography−mass spectrometry; Citrus