Abstract: Due to the serious resource waste and environmental pollution induced by wheat straw in China, wheat straw was used by Chaetomium globosum CGMCC 6882 to produce exopolysaccharide in present work. Meanwhile, the structure of the exopolysaccharide and its antioxidant activity were investigated. Results showed that monosaccharide composition of the polysaccharide produced by C. globosum CGMCC 6882 was rhamnose, glucosamine, galactose, glucose, xylose, fructose and glucuronic acid in a molar ratio of 21.46∶1.58∶1.11∶55.15∶36.37∶7.04∶7.34, and its molecular weight was 3.538×104 Da. Antioxidant assays in vitro revealed that the polysaccharide had strong scavenging effects on DPPH radical, hydroxyl radical, superoxide anions and ABTS radical in a dose-dependent manner. At the concentration of 5 mg/mL, the corresponding scavenging abilities of the polysaccharide were (83.08±2.58)%, (81.39±1.47)%, (79.38±2.03)% and (85.69±1.62)%, respectively. Results of cell antioxidant test showed that the activity of MDA decreased from (15.8±0.25) μmol/g to (7.5±0.31) μmol/g, which was negatively correlated with the concentration of polysaccharide. Furthermore, the activity levels of SOD, CAT and GSH-Px in H2O2 induced Caco-2 cells increased from (147.28±4.82), (11±1.15) and (18.08±1.96) U/mg to (238.89±3.91), (39.12±0.76) and (41.35±2.18) U/mg, and those were positively correlated with the concentration of polysaccharide. Overall, this work provides an important reference and theoretical basis for the efficient utilization of wheat straw.
王子朝,郭佳源,郜文硕,等. 球毛壳菌CGMCC 6882利用小麦秸秆发酵生产抗氧化多糖[J]. 食品与发酵工业, 2021, 47(10): 185-191.
WANG Zichao,GUO Jiayuan,GAO Wenshuo,et al. Production of an antioxidant polysaccharide from wheat straw by Chaetomium globosum CGMCC 6882[J]. Food and Fermentation Industries, 2021, 47(10): 185-191.
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