Characterization of C-glycosyl flavones O-glycosylated by liquid chromatography–tandem mass spectrometry

• Published in: Journal of Chromatography A Vol. 1161; no. 1; pp. 214 - 223
• Main Authors: Ferreres, F., Gil-Izquierdo, A., Andrade, P.B., Valentão, P., Tomás-Barberán, F.A.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 17-08-2007; Elsevier
• Subjects: Agronomy. Soil science and plant productions; Avena sativa; Beta vulgaris; Biological and medical sciences; Briza media; Chemical constitution; chemical structure; Chromatography, Liquid - methods; Economic plant physiology; flavones; Flavones - chemistry; Fundamental and applied biological sciences. Psychology; General pharmacology; Glycosylation; Gypsophila paniculata; liquid chromatography; Mass spectrometry; Medical sciences; O-Glycosyl- C-glycosyl flavones; Passiflora incarnata; Pharmacognosy. Homeopathy. Health food; Pharmacology. Drug treatments; plant extracts; Rumex induratus; Spectrometry, Mass, Electrospray Ionization - methods; Tandem Mass Spectrometry - methods; Triticum aestivum; ultraviolet radiation diode array detection; Avena sativa; Briza media; Passiflora incarnata; O-Glycosyl- C-glycosyl flavones; Gypsophila paniculata; Beta vulgaris; Mass spectrometry; Triticum aestivum; Rumex induratus; Monocotyledones; Chemical analysis; Oat; Passifloraceae; HPLC chromatography; Flavonoid; Cereal crop; Disaccharide; Electrospray; Medicinal plant; Gramineae; Dicotyledones; Angiospermae; Diode array; Qualitative analysis; Glycoside; O-Glycosyl-C-glycosyl flavones; C-Glycoside; Trisaccharide; Aldose; Polygonaceae; Coupled method; Pharmacognosy; Rumex; Chenopodiaceae; Ultraviolet detector; Mass spectrometry MS/MS; Plant origin; Flavone derivatives; Cereal; Herbaceous plant; Spermatophyta; Structural analysis
• ISSN: 0021-9673
• DOI: 10.1016/j.chroma.2007.05.103

Fifty three
O-glycosyl-
C-glycosyl flavones with
O-glycosylation on phenolic hydroxyl or on the
C-glycosyl residue or combination of both forms have been studied by liquid chromatography-UV diode array detection-electrospray ionisation mass spectrometry ion trap in the negative mode. The study of the relative abundance of the main ions from the MS preferential fragmentation on
–MS2 and/or
–MS3 events allows the differentiation of the position of the
O-glycosylation, either on phenolic hydroxyl or on the sugar moiety of
C-glycosylation. In addition, it is possible to discriminate between
O-glycosylation at 2″ and at 6″ positions. The occurrence of an abundant ion
Y
0
−
([(
M
−
H
)
-132/-146/-162]
−, mono-
O-pentosyl/rhamnosyl/hexosyl-
C-glycosyl derivatives) after
–MS2 fragmentation characterizes the
O-glycosylation on phenolic hydroxyls. The preferential fragmentation leading to a relevant
Z
1
−
(
[Y
1
-18]
−) fragment is characteristic of 2″-
O-glycosyl-
C-glycosyl derivatives. The 6″-
O-glycosyl-
C-glycosyl derivatives are characterized by
0,2
X
0
−
, which is generated by a global loss of the sugar moiety from the
O-glycosylation at 6″ and the glycosidic fraction that involves the carbons 6″-3″ of the
C-glycosyl residue (
[(
M
−
H
)
-162-120]
−
, in the case of 6″-
O-hexosyl-
C-hexosyl derivatives). Regarding the combined
O-glycosylated compounds (both on phenolic hydroxyl and on sugar moiety at
C-glycosylation), the main fragmentation on
–MS2 events produces a
Y
0
−
characterizing the
O-glycosylation on the phenolic hydroxyl, and the –
MS3[(
M
−
H
)
→
Y
0
]
− fragmentation of the
O-glycosylation on the
C-glycosyl residue.