Structural characteristics and antioxidant activities of different families of 4-acetamido-TEMPO-oxidised curdlan

Jing Kun Yan, Hai Le Ma, Pan Fu Cai, He Nan Zhang, Qi Zhang, Nan Zi Hu, Xiao Bo Feng, Jianyong Wu

Research output: Journal article publicationJournal articleAcademic researchpeer-review

35 Citations (Scopus)

Abstract

Regioselective oxidation was applied to commercial curdlan for the preparation of its water-soluble derivatives with improved antioxidant activities, using a 4-acetamido-2, 2, 6, 6-tetramethylpiperidine-1-oxyl radical/NaClO/NaClO2system at pH 4.8 and 40 °C. The structural features, molecular properties, and chain conformations of the oxidised curdlans were determined using Fourier transform (FT) infrared and FT Raman spectroscopy, carbon nuclear magnetic resonance, X-ray diffraction, and size-exclusion chromatography with multi-angle laser-light scattering analyses. The C6 primary hydroxyls of curdlan were successfully oxidised into carboxylate groups with less depolymerization, and no aldehyde groups were formed during oxidation. The crystalline region of curdlan was destroyed after oxidation. The oxidised curdlans formed random coils in aqueous solution, and the chain became more flexible and expanded with increasing carboxylate contents from 2.07 mmol/g to 4.87 mmol/g. The high polyglucuronic acid derivative (Cur-24) showed the best antioxidant activity in TEAC and FRAP assays, thus it could be explored as novel potential antioxidants for dietary and therapeutic applications.
Original languageEnglish
Pages (from-to)530-535
Number of pages6
JournalFood Chemistry
Volume143
DOIs
Publication statusPublished - 1 Jan 2014

Keywords

  • 4-Acetamido-TEMPO
  • Antioxidation
  • Chain conformation
  • Curdlan
  • Oxidation

ASJC Scopus subject areas

  • Analytical Chemistry
  • Food Science

Cite this