Production and characterization of extracellular carbohydrate polymer from Cyanothece sp. CCY 0110

► The marine cyanobacterium Cyanothece sp. CCY 0110 is an efficient RPS producer. ► Amount of carbohydrates released is mainly related to the number of cells (growth). ► Light is a key factor with high light intensities enhancing RPS production. ► RPS: Nine residues (two uronic acids), sulfate groups, peptides, thermostable, amorphous. ► Potential for biotechnological applications.