The browser you are using is not supported by this website. All versions of Internet Explorer are no longer supported, either by us or Microsoft (read more here: https://www.microsoft.com/en-us/microsoft-365/windows/end-of-ie-support).

Please use a modern browser to fully experience our website, such as the newest versions of Edge, Chrome, Firefox or Safari etc.

Characterization of acetylated 4-O-methylglucuronoxylan isolated from aspen employing 1H and 13C NMR spectroscopy

På svenska

Author

Summary, in English

Water-soluble hemicelluloses were extracted from milled aspen wood (Populus tremula) employing microwave oven treatment at 180oC for 10 min. The final pH of this extract was 3.5. From this extract oligo- and polysaccharides were isolated and subsequently fractionated by size-exclusion chromatography. The structures of the saccharides in three of the fractions obtained were determined by 1H and 13C NMR spectroscopy, using homonuclear and heteronuclear two-dimensional techniques. The polysaccharides present in the two fractions eluted first were O-acetyl-(4-O-methylglucurono)xylans. The average degree of acetylation of the xylose residues in these compounds was 0.6. The structural element ->4)[4-O-Me-α-d-GlcpA-(1->2)][3-O-Ac]-β-d-Xylp-(1-> could also be identified. On the average, these two xylans were composed of the following (1->4)-linked β-d-xylopyranosyl structural elements: unsubstituted (50 mol%), 2-O-acetylated (13 mol%), 3-O-acetylated (21 mol%), 2,3-di-O-acetylated (6 mol%) and [MeGlcA α-(1->2)][3-O-acetylated] (10 mol%). Most of the 4-O-methylglucuronyl and acetyl substituents in the isolated polysaccharides survived the microwave oven treatment. The third fraction, eluted last, contained acetylated xylo-oligosaccharides, with minor contamination by an acetylated mannan. In the case of these xylo-oligosaccharides, the average degree of acetylation was 0.3.

Publishing year

2000

Language

English

Pages

807-815

Publication/Series

Carbohydrate Research

Volume

329

Issue

4

Document type

Journal article

Publisher

Elsevier

Topic

  • Biological Sciences

Keywords

  • Aspen wood (Populus tremula)
  • Hemicellulose
  • Xylan
  • extraction
  • structure
  • O-Acetylation
  • fractionation
  • Microwave oven

Status

Published

ISBN/ISSN/Other

  • ISSN: 1873-426X