title: Analysis of flavonol glycoside isomers from leaves of Maytenus ilicifolia by offline and online high performance liquid chromatography-electrospray mass spectrometry.
abstract: Flavonol glycosides present in leaves of Maytenus ilicifolia, were examined after fractionation on silica-gel column. Flavonol mono-, di-, tri-, and tetraglycosides, containing kaempferol, quercetin or myricetin were identified by offline electrospray mass spectrometry. Increasing the cone energy induced to adducts variation, from H(+) to Na(+). Protonated ions were characteristically fragmented by sequentially removing the monosaccharide residues, whereas in the sodiated ions, the aglycone was firstly removed. Online high performance liquid chromatography-mass spectrometry, with simple gradients of water, acetonitrile and acetic acid indicated the presence of several isomers, which were further identified by gas chromatography-mass spectrometry as containing galactose or glucose.
authors.affiliation: Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Paraná, CP 19046, CEP 81531-980, Curitiba-PR, Brazil.
authors.forename: Lauro M
authors.initials: LM
authors.lastname: de Souza
authors.forename: Thales R
authors.initials: TR
authors.lastname: Cipriani
authors.forename: Rodrigo V
authors.initials: RV
authors.lastname: Serrato
authors.forename: Denise E
authors.initials: DE
authors.lastname: da Costa
authors.forename: Marcello
authors.initials: M
authors.lastname: Iacomini
authors.forename: Philip A J
authors.initials: PA
authors.lastname: Gorin
authors.forename: Guilherme L
authors.initials: GL
authors.lastname: Sassaki