Study On Extraction Of Selenium-Protein Polysaccharide From Qinba Selenium-Mushroom

Selenium-protein polysaccharide from Qinba selenium-mushroom has good health function. For example, selenium-protein polysaccharide can greatly increase body's immunity, induce the apoptosis of tumor cells and inhibit the activity of telomerase. It can advance the generation of hematopoietic stem cells and progenitor cells in mice to improve their hematopoietic function. It is a good antioxidant and has excellent ability of lead excretion. We used Qinba selenium-mushroom as experimental material for the first time to study the optimal extraction process of selenium-protein polysaccharide.Firstly, the extraction of polysaccharides from Qinba selenium-mushroom with water followed by precipitation with ethanol was investigated in this paper, and the anthrone-sulphuric acid method was used to determine the content of polysaccharides. In hot water extraction process, the influences of extraction temperature, extraction time, the ratio of material to solvent and extraction times on polysaccharide purity and polysaccharide yield were investigated to get the optimal extraction conditions. Under the optimal extraction conditions, the polysaccharide purity was 54.53%, and the polysaccharide yield was 10.16%. In ethanol precipitation process, the influence of concentration,addition of ethanol,pH of solution and content of NaCl on the precipitation ratio of polysaccharides were also studied to obtain the optimal precipitation conditions. Under the optimal precipitation conditions, the polysaccharide purity improved to 79.79% and the polysaccharide yield improved to 12.14%.Secondly, the optimal conditions of removing protein from polysaccharides by the Sevag method were studied by orthogonal experiments. The influences of the volume ratio of chloroform to normal butanol, the volume ratio of sample to chloroform–normal butanol and the time of oscillation on the deproteinization rate and loss rate of polysaccharides were investigated. The content of protein in polysaccharides from Qinba selenium-mushroom was 3.4%. After the treatment of Sevag method, lots of polysaccharides were lost, and the polysaccharides purity decreased. Therefore Sevag method was not applicable to deproteinization process from Qinba selenium-mushroom polysaccharides. Finally, the extraction process of selenium-protein was studied in the paper in order to reduce the loss of selenium. The influence of concentration of extractants, extraction temperature, extraction time and the ratio of material to solvent on the content and extraction rate of selenium were investigated to get the optimal conditions. Under the optimal extraction conditions, the extraction rate of selenium improved to 21.92%...