MOST-USDA Joint Research Center for Food Safety, School of Agriculture and Biology, State Key Lab of Microbial Metabolism, Shanghai Jiao Tong University, Shanghai 200240, China.
College of Agriculture Science, Zhengzhou University, Zhengzhou 450001, China.
Int J Biol Macromol. 2022 Jun 15;210:504-517. doi: 10.1016/j.ijbiomac.2022.04.203. Epub 2022 May 1.
This study aimed to investigate the chemical structure, physicochemical properties, antioxidant capacity, antibacterial ability and anti-biofilm formation activity of an exopolysaccharide (EPS) produced by Lactobacillus curvatus SJTUF 62116 from the fish Gymnocypris przewalskii. The purified EPS, denoted as EPS-1, was mainly composed of glucose and mannose at a relative molar ratio of 1:1.05 with molecular weight of 31.9 kDa. The chemical structure of EPS-1 was consisted of →2)-α-D-Manp-(1→, →4)-α-D-Manp-(1→, →3,6)-α-D-Manp-(1→, T-β-D-Glcp-(1→, →6)-β-D-Glcp-(1→, and →3)-β-D-Glcp-(1→ glycosidic bonds. A sheet-like structure of dried EPS-1 was determined by scanning electron microscope (SEM), whilst a peak-shaped structure of EPS-1 was observed by atomic force microscope (AFM). The degradation temperature of EPS-1 was determined as 300.21 °C using thermogravimetric analysis (TGA). Moreover, the antioxidant capacity of EPS-1 at a concentration of 5.0 mg/mL against DPPH and ABTS was 84.50% and 92.53%, respectively. Furthermore, EPS-1 exhibited acceptable bacteriostatic efficacy against S. Enteritidis, E. coli, and S.aureus with significant inhibition of S. Enteritidis biofilm formation.
本研究旨在探究从青海湖裸鲤中分离出的弯曲乳杆菌 SJTUF 62116 所产胞外多糖（EPS）的化学结构、理化性质、抗氧化能力、抑菌能力和抗生物膜形成活性。纯化后的 EPS 命名为 EPS-1，主要由葡萄糖和甘露糖组成，摩尔比为 1:1.05，分子量为 31.9 kDa。EPS-1 的化学结构由 →2)-α-D-Manp-(1→、→4)-α-D-Manp-(1→、→3,6)-α-D-Manp-(1→、T-β-D-Glcp-(1→、→6)-β-D-Glcp-(1→和 →3)-β-D-Glcp-(1→糖苷键组成。扫描电子显微镜（SEM）显示 EPS-1 为片状结构，原子力显微镜（AFM）显示 EPS-1 为峰状结构。热重分析（TGA）结果表明 EPS-1 的降解温度为 300.21°C。此外，浓度为 5.0 mg/mL 时，EPS-1 对 DPPH 和 ABTS 的抗氧化能力分别为 84.50%和 92.53%。同时，EPS-1 对肠炎沙门氏菌、大肠杆菌和金黄色葡萄球菌具有良好的抑菌效果，且能显著抑制肠炎沙门氏菌生物膜的形成。
