Rapid analysis of unsaturated acidic xylooligosaccharides from kraft pulps using capillary zone electrophoresis

✍ Scribed by Rydlund, Annika ;Dahlman, Olof

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 473 KB
• Volume: 20
• Category: Article
• ISSN: 0935-6304
• DOI: 10.1002/jhrc.1240200205

✦ Synopsis

Abstract

Several acidic xylooligosaccharides containing unsaturated “hexenuronic acid” units, i.e. 4‐deoxy‐L‐threo‐hex‐4‐enopyranosy‐lurinic acid (4‐ΔU) units, were separated as their alditol derivatives by capillary zone electrophoriesis in 438 mM borate buffer (pH 10.3) and were detected selectively at the μM level on‐column UV detection at 232 nm. These acidic oligosaccharides were obtained from birch and pine kraft pulps on enzymatic hydrolysis with endoxylanases and subsequent treatment with other Trichoderma reesei enzymes. Under the conditions empolyed, acidic 4‐ΔU‐containing xylooligosaccharides with a molecular size renging from trisaccharides up to nonasaccharides could be separated. Oligosaccharides with higher molecular mass were detected first. Two 4‐ΔU‐xylotetraose isomers, with the 4‐ΔU‐group linked to different xylose units in the iligosaccharide backbone, could be resolved from each other with a resolution of about 1. By using a disaccharide (4‐ΔU α‐(1 → 4) linked to N‐acetyl glucosamine) as a model compound the minimum detectable concentration was determined as 10 μM.