The composition of the equilibrium between aldehydes and hemiacetals was evaluated by ionspray ionization tandem mass spectrometry. The methanolic extracts of virgin olive oil from Carolea and Coratina cultivars contain a complex mixture of hydroxytyrosol (3) and tyrosol (4) derivatives (5, 6) characterized by the presence of aldehyde moieties in equilibrium with their hydrated form (8) or with the corresponding methanol hemiacetals 9 and 10. The equilibrium was frozen by droplet evaporation, thus allowing the structure determination of each component. The formation of the decarboxylated species 11-14, reported previously, was not observed. Copyright (C) 2000 John Wiley and Sons, Ltd.
Virtual freezing of the hemiacetal-aldehyde equilibrium of the aglycones of oleuropein and ligstroside present in olive oils from Carolea and Coratina cultivars by ionspray ionization tandem mass spectrometry
De Nino A.;Perri E.;Procopio A.;Sindona G.
2000-01-01
Abstract
The composition of the equilibrium between aldehydes and hemiacetals was evaluated by ionspray ionization tandem mass spectrometry. The methanolic extracts of virgin olive oil from Carolea and Coratina cultivars contain a complex mixture of hydroxytyrosol (3) and tyrosol (4) derivatives (5, 6) characterized by the presence of aldehyde moieties in equilibrium with their hydrated form (8) or with the corresponding methanol hemiacetals 9 and 10. The equilibrium was frozen by droplet evaporation, thus allowing the structure determination of each component. The formation of the decarboxylated species 11-14, reported previously, was not observed. Copyright (C) 2000 John Wiley and Sons, Ltd.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
