1. Characterization and Antioxidant Activity of the Exopolysaccharide Produced by Bacillus amyloliquefaciens GSBa-1
- Author
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Xiao Na Hao, Yunyun Jiang, Jian Zhang, Zhennai Yang, Liu Li, Wen Zhao, and Xiao Zhao
- Subjects
0301 basic medicine ,chemistry.chemical_classification ,Molecular mass ,Bacillus amyloliquefaciens ,biology ,Chemistry ,DPPH ,General Medicine ,biology.organism_classification ,Applied Microbiology and Biotechnology ,Sepharose ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,Monosaccharide ,Hydroxyl radical ,Food science ,Ethanol precipitation ,Biotechnology ,Glucan - Abstract
The exopolysaccharide (EPS) produced by Bacillus amyloliquefaciens GSBa-1 was isolated and purified by ethanol precipitation, and DEAE-cellulose and Sepharose CL-6B chromatographies. The molecular mass of the purified EPS was determined to be 54 kDa. Monosaccharide analysis showed that the EPS was composed of predominantly glucose, and it was further confirmed by NMR spectroscopy to be α-glucan that consisted of a trisaccharide repeating unit with possible presence of two α-(1→3) and one α-(1→6) glucosidic linkages. Microstructural analysis showed that the EPS appeared as ellipsoid or globose with a smooth surface. The EPS had a degradation temperature at 240°C. Furthermore, the EPS had strong DPPH and hydroxyl radical scavenging activities, and moderate superoxidant anion scavenging and metal ion-chelating activities. This is the first characterization of a glucan produced by B. amyloliquefaciens with strong antioxidant activity. The results of this study suggest the potential of the EPS from B. amyloliquefaciens GSBa-1 to serve as a natural antioxidant for application in functional products.
- Published
- 2018