Song Jia, Jia Yu-Xiang, Su Yan, Zhang Xiao-Yu, Tu Lin-Na, Nie Zhi-Qiang, Zheng Yu, Wang Min
State Key Laboratory of Food Nutrition and Safety; Key Laboratory of Industrial Fermentation Microbiology; Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control; College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, China.
Key Laboratory of Chemical Biology and Molecular Engineering, Ministry of Education, Institute of Biotechnology, Shanxi University, Taiyuan 030006, China.
Polymers (Basel). 2020 Feb 5;12(2):348. doi: 10.3390/polym12020348.
Scleroglucan is widely used in the food and chemical industries because of its good rheological property, stability, and emulsification activity. To investigate the influence of different carbon sources on the properties and synthesis of exopolysaccharides (EPS), the three EPSs (GEPS, glucose was used as the carbon source; LEPS, lactose was used as the carbon source; and SEPS, sucrose was used as the carbon source) were determined, respectively. It was found that the yield and viscosity of exopolysaccharides were different. When sucrose and glucose were used as the carbon sources, the viscosity and yield of EPS were both higher than lactose. The scanning electron microscopy (SEM) images showed that the three EPSs had different morphologies, but the monosaccharide analysis showed that they were all composed of glucose units. Fourier transform infrared spectroscopy (FT-IR) proved that there were no additional substituents for the three EPSs. Furthermore, the high performance liquid chromatography (HPLC) results showed that SEPS and LEPS had two fractions. Through the analysis of proteomics data, there were few differences in the metabolic pathways between GEPS and SEPS, but a significant difference between LEPS and SEPS. Our study provides a theoretical basis and reference for understanding the biosynthesis of exopolysaccharides and the development of different types of EPS products.
硬葡聚糖因其良好的流变学性质、稳定性和乳化活性而被广泛应用于食品和化学工业。为了研究不同碳源对胞外多糖（EPS）性质和合成的影响，分别测定了三种EPS（GEPS，以葡萄糖为碳源；LEPS，以乳糖为碳源；SEPS，以蔗糖为碳源）。结果发现，胞外多糖的产量和粘度各不相同。当以蔗糖和葡萄糖为碳源时，EPS的粘度和产量均高于乳糖。扫描电子显微镜（SEM）图像显示，三种EPS具有不同的形态，但单糖分析表明它们均由葡萄糖单元组成。傅里叶变换红外光谱（FT-IR）证明，三种EPS均没有额外的取代基。此外，高效液相色谱（HPLC）结果表明，SEPS和LEPS有两个组分。通过蛋白质组学数据分析，GEPS和SEPS之间的代谢途径差异不大，但LEPS和SEPS之间存在显著差异。我们的研究为理解胞外多糖的生物合成以及不同类型EPS产品的开发提供了理论依据和参考。
