The Effects for Extracellular Polymeric Sustances of Cladophora glomerata under Different Culture pH and Salinities

Abstract

The extracellular polymeric sustances (EPS) of algae have been studied as high-value natural resources for a number of application. Cladophora glomerata is the most abundant algae in freshwater throughout the world. This study discovered that under algal favoured pH environment, changing culture salinity can induce C. glomerata to secrete massive amount of EPS. Under pH 7.0 and pH 8.0, the total EPS increased from 3.10 mg g-1 fresh algae to 6.47 mg g-1 fresh algae, the protein to polysaccharide ratio (P/S) decreased from 0.31 to 0.21 with the increase in the salinity from 0 ‰ to 30.0‰. For pH 5.0, 6.0 and pH 9.0, 10.0 culture conditions, the total EPS between1.17 mg g-1 fresh algae to 4.32 mg g-1 fresh algae, the P/S ratio between 0.24 to 0.29 with the increase in the salinity from 0 ‰ to 30.0‰. Therefore, the total EPS and P/S ratio are influenced by culture salinity and pH obviously.