Structures of enzymically derived oligosaccharides from sorghum glucuronoarabinoxylan

Carbohydr Res. 1998 Jan;306(1-2):265-74. doi: 10.1016/s0008-6215(97)10064-7.


Oligosaccharides derived from alkali-extracted sorghum glucuronoarabinoxylan by digestion with a combination of (1-->4)-beta-D-arabinoxylan arabinofuranohydrolase (AXH) and endo-(1-->4)-beta-D-xylanase (Xyl I), both from Aspergillus awamori, were purified by size-exclusion chromatography followed by preparative high-performance anion-exchange chromatography. Structural studies including monosaccharide analysis, methylation analysis, 1H NMR spectroscopy, and mass spectrometry were carried out, resulting in the characterisation of four novel oligosaccharides, namely, alpha-D-GlcpA-(1-->2)-beta-D-Xyl p-(1-->4)-beta-D-Xyl p-(1-->4) -beta-D-Xyl p, alpha-D-GlcpA-(1-->2)-beta-D-Xyl p-(1-->4) [alpha-L-Araf-(1-->3)]-beta-D-Xyl p-(1-->4)-beta-D-Xyl p, alpha-D-GlcpA-(1-->2)-beta-D- Xyl p-(1-->4)-beta-D-Xyl p-(1-->4)[alpha-L-Araf-(1-->2)-alpha)-alpha- L-Araf-(1-->3)]-beta-D-Xyl p-(1-->4)-beta-D-Xyl p, and alpha-D-GlcpA-(1-->2) -beta-D-Xyl p-(1-->4)[alpha-L-Araf-(1-->3] beta-D-Xyl p-(1-->4)[alpha-L-Araf-(1-->2)-alpha-L-Araf-(1-->3)] -beta-D-Xyl p-(1-->4)-beta-D-Xyl p. The various oligosaccharides identified provide additional insight into the structure of sorghum glucuronoarabinoxylan. Furthermore, novel data were generated with respect to the substrate specificity of AXH and Xyl I towards glucuronoarabinoxylans in general.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aspergillus / enzymology
  • Carbohydrate Sequence
  • Edible Grain / chemistry*
  • Endo-1,4-beta Xylanases
  • Fungal Proteins / metabolism
  • Glycoside Hydrolases / metabolism*
  • Magnetic Resonance Spectroscopy
  • Methylation
  • Molecular Sequence Data
  • Oligosaccharides / chemistry*
  • Oligosaccharides / isolation & purification
  • Spectrometry, Mass, Fast Atom Bombardment
  • Substrate Specificity
  • Xylans / chemistry*
  • Xylans / isolation & purification
  • Xylosidases / metabolism*


  • Fungal Proteins
  • Oligosaccharides
  • Xylans
  • glucuronoarabinoxylan
  • Glycoside Hydrolases
  • Xylosidases
  • alpha-N-arabinofuranosidase
  • Endo-1,4-beta Xylanases