Structure identification of feruloylated oligosaccharides from sugar-beet pulp by NMR spectroscopy

✍ Scribed by Ian J. Colquhoun; Marie-Christine Ralet; Jean-François Thibault; Craig B. Faulds; Gary Williamson

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 1013 KB
• Volume: 263
• Category: Article
• ISSN: 0008-6215
• DOI: 10.1016/0008-6215(94)00176-6

✦ Synopsis

1D NMR ('H and 13C) and 2D NMR spectroscopy have been used to determine the structure of feruloylated oligosaccharides obtained by enzymic degradation or mild acid hydrolysis of sugar-beet pulp. Feruloylated oligosaccharides derived from pectic neutral side-chains containing arabinose or galactose residues were identified. In the feruloylated arabinose oligosaccharides, feruloyl groups were linked to O-2 of L-Araf residues. The structure of the feruloylated arabinose disaccharide was identified as 0-[2-O-(trunsferuloyl)a-L-Ara f l-(1 -+ 5)-L-Araf and that of the feruIoylated arabinose trisaccharide as 0-cY-L-Araf-(1 4 3)-0-[2-0-(Pans-feruloyl)*-L-Arafl-(1 4 5)-L-Araf. The structure of the feruloylated galactose disaccharide was identified as 0-[6-0-(Puns-feruloyl)-@-b-GalpI-(1 + 4)-D-Galp.

From our results, we suggest that the feruloyl groups present in sugar-beet pulp are linked to the arabinofuranosyl residues of the main core of a-(1 + 5)-linked arabinan chains and to the galactopyranosyl residues of the main core of p-(1 -+ 4)-linked type I galactan chains.