Identification and Semiquantitation of Monoterpene Glycosides in Ripening Muscat of Alexandria Grapes

This Application Note presents the workflow and software used to study monoterpene glycosides in Muscat of Alexandria grapes at different stages of ripening. An Agilent 1290 Infinity LC with an Agilent 6530 Accurate-Mass Q-TOF LC/MS was used to identify and semiquantitate the abundance of 18 different monoterpene glycosides found in the grapes. The process starts with the creation of a Personal Compound Database Library (PCDL) and the search for potential compounds with untargeted single mass spectrometry. Second, is the generation of fragmentation spectra through auto MS/MS. From the fragments, the correlation and identification of structures are done using Agilent Molecular Structure Correlator (MSC). The process finishes with an update of the PCDL with the found retention times and the creation of an Agilent MassHunter quantitative analysis method that will auto-integrate chromatograms for semiquantitation. This process allows for the identification and semiquantitation of nonvolatile molecules in the absence of chemical standards and without derivatization. Identification and Semiquantitation of Monoterpene Glycosides in Ripening Muscat of Alexandria Grapes