Effect of Pseudoalteromonas sp. MEBiC 03485 on biomass production and sulfated polysaccharide biosynthesis in Porphyridium cruentum UTEX 161

The effect of co-cultivation of Porphyridium cruentum UTEX 161 with Pseudoalteromonas sp. MEBiC 03485 on P. cruentum growth and its sulfated polysaccharide (EPS) production were examined. The strain MEBiC 03485 had beneficial effects on P. cruentum growth, EPS production, and EPS quality. These effects were due to a compound secreted by the strain MEBiC 03485. Notably, secretory compound treatment also increased intracellular phycoerythrin and phycocyanin content by 89.4% and 161%, respectively. In addition, the biological activities of EPS extracted from MEBiC 03485 treatment tended to be higher than the control without treatment. Our results suggest a novel approach for potentially enhancing the growth of P. cruentum and its EPS production and quality by co-culturing with the symbiotic strain MEBiC 03485.