太湖蓝藻藻蓝蛋白的提取及纯化

为利用太湖打捞蓝藻的蛋白质资源,采用冻融破壁、絮凝、盐析、透析、双水相萃取等方法制备荧光试剂级藻蓝蛋白。研究结果表明,以水为介质冻融2次破壁,将冻融藻浆中蓝藻干物质调节为0.95%,用浓度为7.5g/L的聚合氯化铝絮凝初分离,所得藻蓝蛋白纯度(A6 20/A280)为0.31;采用20%、50%饱和度的硫酸铵两步盐析可将其纯度(A620/A280)提高至2.29;盐析后藻蓝蛋白经100 000的透析袋透析,再以140 g/L的聚乙二醇(分子量2 000)和140 g/L的磷酸钾盐萃取纯化,最终纯度(A620/A280)高达4.60,达到荧光试剂级要求。

Extraction and purification of phycocyanin from blue algae in Lake Taihu

To utilize the protein resources in blue algae in Lake Taihu,an approach,which included repeated freeze-thaw cycles,flocculation,ammonium sulfate salting-out,and aqueous two-phase extraction was developed to obtain high purity phycocyanin.By freezing and thawing blue algae two times in water,the concentration of algae dry matter was adjusted to 0.95%.After flocculation by 7.5 g/L polymeric aluminum chloride,the phycocyanin with the purity(A620/A280) of 0.31 was isolated.The purity was improved to 2.29 through two-step salting-out with ammonium sulfate.Following the salting-out,the phycocyanin was dialyzed in a dialysis bag with molecular weight cut off of 100 000,and was then extracted with 140 g/L polyethylene glycol 2000 and 140 g/L potassium phosphate salt.Those steps led to a higher purity of phycocyanin,(A620/A280) being 4.60,which met the standard of fluorescent reagent grade.