Flavonol glucoside profile of southern Italian red onion (Allium cepa L.).
High-performance liquid chromatography-diode array detector (HPLC-DAD) coupled with electron spray mass spectrometry (ESI-MS-MS) was used to determine the flavonol profile in southern Italian red onions (Allium cepa L.). This on-line technique allowed the identification of seven flavonols in southern Italian red onion, quercetin 4'-glucoside and quercetin 3,4'-diglucoside being the most abundant components. Five minor flavonols have been recognized, offering a characteristic profile of such compounds in red onions under study. Quercetin 3-glucoside, quercetin 7,4'-diglucoside, quercetin 3,7,4'-triglucoside, and isorhamnetin 4'-glucoside have been previously reported as minor flavonoid components in Allium cepa, while isorhamnetin 3,4'-diglucoside was previously found in Allium ascalonicum. Traces of isorhamnetin 3-glucoside and free quercetin were also detected.
Bonaccorsi
Paola
P
Dipartimento di Chimica Organica e Biologica, Università di Messina, Salita Sperone 31, 98166 S. Agata di Messina, Italy. paolab@isengard.unime.it
Caristi
Corrado
C
Gargiulli
Claudia
C
Leuzzi
Ugo
U
D002851:Chromatography, High Pressure Liquid / Q000379:methods; D044948:Flavonols / Q000032:analysis*; D005960:Glucosides / Q000032:analysis*; D019697:Onions / Q000737:chemistry*; D011794:Quercetin / Q000032:analysis / Q000031:analogs & derivatives; D021241:Spectrometry, Mass, Electrospray Ionization
D044948:Flavonols; D005960:Glucosides; C047368:3-methylquercetin; D011794:Quercetin