Characterization of Extracellular Polymeric Substance (EPS) from Cladophora Glomerata under Different Culture Salinities

Abstract

 Abstract—Cladophora glomerata is the most abundant algae in freshwater throughout the world. This study discovered that changing culture salinity can induce C. glomerata to produce massive amounts of EPS. Comparing the contents and characteristic functional groups of the EPS under different culture salinity conditions. The contents of protein (2.15-2.71 mg g -1 ) and polysaccharide (6.94-12.64 mg g -1 ) variable increased with increased culture salinity; the ratios if protein to polysaccharide decreased with the increased culture salinity. The FTIR spectra analysis suggested that protein (1640-1680 cm -1 ) and polysaccharide (1120-1170 cm -1 ) were the major components in EPS. Therefore, the range of contents in EPS and the ratios of protein to polysaccharide are influenced by culture salinity This study compared the content and characteristic functional groups of the EPS from the C. glomerata under different culture salinity. The results showed that (1) Thickness of mucilage layer increase with the increase of EPS level. (2) Polysaccharide concentration changed from 6.94 to 12.64 mg g -1 , and the protein concentration changed from 2.15 to -2.71mg g -1 during the whole tests. (3) Content of protein under all different salinities were found to be lower than polysaccharide. (4) The ratios of protein to polysaccharide decresaed with increased culture salinity. (5) The FTIR spectra analysis suggested that protein (1640-1680 cm -1 ) and polysaccharide (1120-1170 cm -1 ) were the major components in EPS. (6) The yield of EPS and fraction EPS contents of algae can controlled by different culture salinity.