Abstract:  Culturing Porphyridium spp. with optimized culture medium and simple photobioreactor was investigated. Apractical technical process on direct separation of Polysaccharide of Porphyridium(PSP) from broth was established, and PSPwas primarily analyzed. The results showed that the biomass of cultured Porphyridium reached 2.1g dry weight per litre, yieldof primary PSP 0.378g/L and efficiency of ion exchange about 78%. PSP was basically composed of xylose, glucose and galactose,with a mass ratio 13.68:7.83:5.23 respectively. The result by IR analysis indicates that PSP has its characteristic absorption peak,and its hexose is of pyranoid form while PSP is sulfated polysaccharide, and its content of –SO3- is about 4%.

Key words: Porphyridium spp. PSP, cultivation, separation of sulfated polysaccharides