Molecular properties and antioxidant activities of polysaccharides isolated from alkaline extract of wild Armillaria ostoyae mushrooms

Ka Chai Siu, Lijian Xu, Xia Chen, Jianyong Wu

Research output: Journal article publicationJournal articleAcademic researchpeer-review

47 Citations (Scopus)

Abstract

This study aims to discover novel and bioactive polysaccharides (PS) from wild Armillaria ostoyae, a honey mushroom species. Two PS designated AkPS1V-1 (66.6 kDa) and AkPS1V-2 (15.3 kDa) were isolated and fractionated by anion ion exchange (IEC) and size exclusion chromatography (SEC) from the alkaline extract of A. ostoyae mushrooms. AkPS1V-1 was a glucan composed of solely glucose residues and AkPS1V-2 a heteropolysaccharide composed of glucose and galactose at 6:1 molar ratio. AkPS1V-2 exhibited higher antioxidant activities than AkPS1V-1 based on reducing power, radical scavenging and metal chelating assays. The structure of AkPS1V-2 was further analyzed and elucidated as a branched galactoglucan with a backbone composed of (1→6)-β-d-glucopyranosyl, (1→3)-β-d-glucopyranosyl, (1→3)-α-d-galactopyranosyl and (1→3,6)-β-d-glucopyranosyl residues at 3:1:1:1 ratio, and side chain of (1→3)-β-d-glucopyranosyl residue. This is the first report on a pure PS structure and its antioxidant activities from this mushroom species.
Original languageEnglish
Pages (from-to)739-746
Number of pages8
JournalCarbohydrate Polymers
Volume137
DOIs
Publication statusPublished - 10 Feb 2016

Keywords

  • Antioxidant activity
  • Armillaria ostoyae
  • Extraction
  • Fractionation
  • Polysaccharides
  • Structure

ASJC Scopus subject areas

  • Organic Chemistry
  • Polymers and Plastics
  • Materials Chemistry

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