title: Structural heterogeneity of wheat arabinoxylans revealed by Raman spectroscopy.
abstract: A set of arabinoxylan samples differing in their arabinose composition and various samples of arabino-xylo-oligosaccharide samples were analysed by Raman spectroscopy. Specific signatures for arabinose substitution were found in several spectral regions, that is, 400-600, 800-950 and 1030-1100 cm(-1). A linear relationship was observed between the peak ratio 855/895 cm(-1) of the second derivative spectra and the A/X ratio determined by chemical analysis. Moreover, spectral changes were observed in the 400-600 cm(-1) region assigned to the coupled vibrations mode in the skeleton: while the intensity of the band at 570 cm(-1) increased with the degree of substitution, that at 494 cm(-1) decreased. Similarly, a linear relationship was observed between the peak intensity ratio 570/494 cm(-1) calculated on the second derivative spectra and the composition data. Analysis of Raman spectra of arabino-xylo-oligosaccharides allowed to identify specific spectral features of disubstitution.
authors.affiliation: INRA-UMR Ingénierie des Agropolymères et Technologies Emergentes, INRA-ENSAM-UMII-CIRAD, 2 place Viala, F-34060 Montpellier, France. barron@ensam.inra.fr
authors.forename: Cécile
authors.initials: C
authors.lastname: Barron
authors.forename: Paul
authors.initials: P
authors.lastname: Robert
authors.forename: Fabienne
authors.initials: F
authors.lastname: Guillon
authors.forename: Luc
authors.initials: L
authors.lastname: Saulnier
authors.forename: Xavier
authors.initials: X
authors.lastname: Rouau
mesh_terms: D013059:Spectrum Analysis, Raman; D014908:Triticum; D014990:Xylans / Q000737:chemistry*
chemical_list: D014990:Xylans; C085118:arabinoxylan