Study Of Polysaccharide From Spirulina Platensis (PSP)

Polysaccharide of Spriulina Platensis (PSP) is , a water-soluble polysacchride advavtageous to enhance immunological competence which have many specical physiological accommodation function and medical effects .In recent years, there is a great market demand for PSP. Utilization of mixotrophic culture and other biophysical method can enhance the growth rate and cell yield of Spirulina Platensis .It is become much more popular to how to obtain much more bioactive compositions such as phycobiliprotein and polysaccharide. This paper has made comparatively through exploraton on the optimal culture conditions and methods, sparation and purification of Polysaccharide of Spirulina Platensis (PSP), the physical and chemical properties of this polysaccharide and its antioxidation was also deterrmined.The main aspects and results are as follows:(1) The effects of temperature, pH, nitrogen concentration and Ca²⁺ on the celluar growth of S.platensis and the polysaccharide content were studied and discussed in order to enhance the specific growth rate, the cell yield of S. platensis and the content of PSP. Those results showed : the mixotrophic growth was better and obtained finally much more cell dry-weight, much more total content of protein and polysaccharide from S. platensis during the temperature of 30 ℃ 35 ℃. In mixtrophic culture , the effects of pH on the growth was not affected by the low concentration of glucose (1.0g/L), its suitable pH was the same as suitable pH of photoautophic growth. The deficent or supernumerary nitrogn was all advantageous to biosynthesis of PSP. The concentration of 2.0g/L NaNO₃ gives the highest specific growth rate , enhance of cell yield and the contents of PSP. Ca²⁺ have an obvious effect on the growth of S.platensis and the synthesis of PSP .water-soluble CaCl₂ of 0.04g/L is the suitable concentration for S.platensis to enhance the specific growth rate and the content of PSP.