Study On Extraction Technology And Hypoglycemic Effect Of Polysaccharide From Selenium-enriched Green Tea

It is reported that tea polysaccharide has the effect of lowering blood glucose.It has been confirmed by more and more experiments that selenium is closely related to the occurrence and development of diabetes.Therefore,on the basis of above two viewpoints,there will be a potential application value to explore the relationship between Se-TPs and diabetes.Enshi,as the world capital of selenium,is rich in selenium-enriched plants such as tea,konjac.However,there are few study regarding the hypoglycemic effect of Se-TPs from Enshi.In our research,we investigate the extraction method and hypoglycemic effect of Se-TPs from Enshi selenium-enriched green tea.In the thesis,we find out the proper technology of selenium-enriched green tea to.Then we used type 1 and type 2 diabetic mice as research objects to investigate the action of Se-TPs by oral administration.The main results were as follows:(1)The extraction and identification of the Se-TPs from Enshi selenium-enriched green tea were achieved by the method of water extraction and alcohol precipitation,infrared spectrum,ultraviolet spectrum,and use anthrone-sulfuric acid determination,Lowry's method and fluorescence method to detect of chemical properties.It was exhibited that the Se-TPs was a kind of acidic glycoprotein by spectrophotometry.The polysaccharide content of Se-TPs was 75.7%;the protein content was 1.58%,and the selenium content was 0.78±0.10?g/g.Altogether,it was proved that the extracted polysaccharide was a kind of polysaccharide containing selenium.(2)The effects of Se-TPs on type 1 diabetic mice were investigated by qRT-PCR,glycogen kit,antioxidant detection kit and the pancreatic HE staining.It was indicated that oral administration of Se-TPs could decrease the blood glucose and serum lipid levels.Se-TPs also increase the serum levels of insulin and body weight.It was also suggested that Se-TPs could enhance activities of pancreatic SOD and GPx,reduce MDA to promote the pancreatic antioxidative capacity.Moreover,Se-TPs could promote the glycogen synthesis,decrease gluconeogenesis gene expression,and repair the damaged islet ? cells.(3)The effect of Se-TPs on type 2 diabetic mice was investigated by qRT-PCR,kit,antioxidant detection kit and the hepatic HE and oil red O stainings.Se-TPs could also decrease blood glucose and gluconeogenesis gene expression,and increase hepatic glycogen.Se-TPs reduced the fat content and enhance the activities of hepatic SOD and GPx,and reduce MDA of liver tissue.Se-TPs presented the ability to repair the damaged islet ? cells.Taken together,Se-TPs from green tea of Enshi could reduce the blood glucose of diabetic mice.Se-TPs could repair the damaged islet ? cells to enhance the insulin level,promote the hepatic glycogen synthesis and inhibit the gluconeogenesis,and promote the antioxidative capacity in diabetic mice for the blood glucose homostasis.