Studies On Extracting Technology And Biological Activity Of Polysaccharide From Nature Spirulina Platensis Growing In Inner Mongolia

After the spirulina platensis was degreased by 95% alcohol crude polysaccharide was isolated from the spirulina platensis growing in eerduosi lakes of Inner Mongolia, alcohol precipitation and removal of protein with different methods was studied. As a result, a simple and easy way obtaining the high ratio of crude polysauharide product was found; the parameters of extracting technology were follows : the ratio of solid to water was 1:9; the extractive temperature was 80℃ ; the extractive time was 6h; the extractive time was 2 times, the extractive water was concentrated by 20% and the precipitation by 4 times alcohol was optimum; protein removal by pronose and sevage was economical. The crude polysaccharide was further purified by column chromatography on DEAE-52 and sephardex G-200, two polysaccharide fractions has been achieved. The two polysaccharide fractions were examined by electrophoresis paper and gel chromatography; the results showed that two fractions were a homoyenous substance. By ultraviolet scanning (200nm-800nm) showed neither theabsorption wave of protein (280nm) nor the absorption wave of nucleic acid (260nm) in polysaccharide of spirulina platensis water solution. In addition, Sephadex G-200 gel chromatography showed the average molecular weight of two fractions was 45300D and 25900D. the further results of studies have been showed that fraction Ⅰcould remarkably antagonize thymatrophy and splenatrophy that were caused by cyclophamide, and enhance the endurance of rats to adversity. It also found that fraction Ⅰhad more inhibitory effect on the growth of gram positive staphylowuns aureus than gram-negative Esch.coli.