Two Novel Exopolysaccharides from Bacillus amyloliquefaciens C-1: Antioxidation and Effect on Oxidative Stress

• DOI: 10.1007/s00284-014-0717-2
• Publication Date: 2014-11-01T14:01:11Z
• Authors: Haixia Yang; Jianjun Deng; Yue Yuan; Daidi Fan; Yan Zhang; Ruijuan Zhang; Bei Han
• Keywords: 0303 health sciences; Superoxide Dismutase; Polysaccharides, Bacterial; Bacillus; Free Radical Scavengers; Hep G2 Cells; Hydrogen Peroxide; Antioxidants; Molecular Weight; Oxidative Stress; 03 medical and health sciences; Malondialdehyde; RNA, Ribosomal, 16S; Fermentation; Humans; Reactive Oxygen Species; Oxidation-Reduction; Phylogeny

Two odorless, water-soluble exopolysaccharide (EPS) fractions, EPS-1 and EPS-2, were isolated from a newly isolated Bacillus amyloliquefaciens strain C-1 and purified by ion exchange and gel chromatography. The purified EPS-1 contained glucose/mannose/galactose/arabinose in a relative proportion of 15:4:2:1, and possessed a molecular weight of 79.6 kDa, while EPS-2 contained only glucose and mannose in a 3:1 ratio, with the molecular weights of 19.8 kDa. The antioxidant activity results showed that EPS-1 exhibited strong reducing power, superoxide radicals (O(2-)·), and hydroxyl free radicals (OH·) scavenging activities. For the H2O2-induced injury in HepG2 cells, EPS-1 significantly decreased the formation of reactive oxygen species, intracellular malondialdehyde levels, and restored intracellular superoxide dismutase activity. For EPS-2, there had no detectable antioxidant activities. And all these results collectively showed that as a natural antioxidant, only EPS-1 produced by C-1 had considerable potential to be used as medical compounds or functional additives.