APRICOT GLYCOSIDICALLY BOUND VOLATILE COMPONENTS

Apricot glycosidically bound components separated from the heterosidic pool by silica gel chromatography, gel filtration, and preparative overpressured layer chromatography (OPLC) were studied by negative ion chemical ionization (NICI) and negative ion desorption chemical ionization (NI-DCI) mass spectrometry (MS) and tandem mass spectrometry (MS/MS). The low-energy collisionally activated (CAD) fragmentation patterns and the use of chromatographic retention data (OPLC and HPLC) have allowed the identification of linalyl, alpha-terpinyl, neryl, geranyl, and benzyl glucosides. The presence of linalyl arabinoglucoside was established by identification of the glucoside derivative obtained by partial enzymatic hydrolysis. The MS and MS/MS spectra agree with the presence of hexyl glucoside and 2-phenylethyl arabinoglucoside. In the presence of ND3 as reagent in mass spectrometry shifts of 3 mass units were indicative of the presence of linalool oxide glucosides (four isomers detected) and shifts of 4 mass units were characteristic of the four dienediol glucosides isolated. One dienediol arabinoglucoside was also tentatively identified using the same method. These results show that glucosides are the major glycosidically bound volatile compounds present in apricot.