Insights into the viscoelastic peculiarities of cyanobacterial extracellular polymeric substance (EPS)

Extracellular polymeric substances (EPSs) can be defined as renewable, high molecular weight polymeric materials produced by bacteria and microorganisms. EPSs are composed of primarily polysaccharides, proteins with minor amounts of nucleic acids, lipids, and humic substances. Cyanobacterial EPSs have a significant physiological effect on bloom formation and stress tolerance in adverse conditions. Therefore, cyanobacterial EPS has an important factor for aquatic life, environment and human life. For these reasons, determining the structure and structure-property relationships of cyanobacterial EPS is important for understanding its behavior and performance. In this study, the identification of the structure-property relationships, thermal and viscoelastic properties of cyanobacterial EPS, X-ray diffraction analysis, differential thermal analysis and dynamic mechanical analysis (DMA) have been performed. Viscoelastic properties of the polymeric materials have been interpreted by certain DMA parameters at a fixed frequency depending on the temperature to understand the performance of cyanobacterial EPS. Because of viscoelastic behavior and termal stability, EPSs present great ecological importance as well as market potential for industrial applications