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Isolation and characterization of an antioxidant exopolysaccharide produced by Bacillus sp. S-1 from Sichuan Pickles
Xinyuan Hu1, Xin Pang1, Peng George Wang2
1The State Key Laboratory of Microbial Technology, School of Life Sciences, and National Glycoengineering Research Center, Shandong University, Jinan, Shandong, China.
Abstract:
It is urgent to explore food-grade EPSs from edible microorganism. In this study, a new type of exopolysaccharide (EPS) secreted by Bacillus sp. S-1 from Sichuan Pickles was isolated and fractioned on anion-exchange and gel-filtration chromatography. As indicated by monosaccharides components analysis, the major component BS-2 mainly consisted of galactose, glucose, and mannose with average molecular weight (Mw) of 1.765 × 104 Da. Moreover, the characterization of EPS was investigated by FT-IR and NMR Spectroscopy. In vitro antioxidant activity assay, it proved that the EPSs possessed potent quenching capacities on superoxide, hydroxyl, and DPPH radicals in a dose-dependent way. Furthermore, the major component BS-2 showed potent protection against oxidative injury by inhibiting H2O2-induced apoptosis in RAW264.7 cells. As suggested by the results, BS-2 might serve as a promising antioxidant agent to be applied in nutraceutical and pharmaceutical industries.
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