[go: up one dir, main page]

Distribution and structural variation of arabinoxylans in common wheat mill streams

J Agric Food Chem. 1999 Jan;47(1):271-5. doi: 10.1021/jf9805294.

Abstract

In 19 wheat-milling fractions total pentosan content, calculated as 0.88 x (% L-arabinose + % D-xylose), varied between 1.44 and 30.66% on dry matter (dm). It increased with ash content once the latter exceeded 0.6% (dm basis). Water-extractable arabinoxylans were recovered by saturating water extracts to 65% ethanol. Their contents in the milling fractions varied between 0.35 and 1.38%, and above 0.6% ash content also increased with this parameter. Their L-arabinose-to-D-xylose ratios ranged between 0.65 and 0.39, with the lowest values found for the fractions with highest ash content, indicating that the ash-rich tissues contain more arabinoxylans that are less branched. (1)H NMR spectroscopy revealed that the decrease in L-arabinose-to-D-xylose ratio was accompanied by an increase in unsubstituted xylose residues and a decrease in disubstituted xylose residues, while the contents of monosubstituted xyloses were virtually constant.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Industry
  • Triticum
  • Xylans / chemistry*

Substances

  • Xylans