Study On Oat Bran Polysaccharide Separation, Purification And Hyooglycemic Effect

Oats is a kind of cereal crops with comprehensive nutritional value,which contains a large amount of nutrients needed by human beings.Oat bran is usually used for feeding animals or just as wastes thrown away by people in their daily life.Undoubtedly,this results in the waste of resources.The test intends to use the technology of ultrasonic assisted extraction to improve the oat bran polysaccharide yield.Through elevant animal experiments,it analyzes the hypoglycemic effect of oat bran polysaccharide,and when oat bran polysaccharide is added to the milk powder for middle aged and elderly people,oat bran can be effectively utilized.The result of the experiment shows that the optimum conditions of extraction of oat bran by ultrasonic is that:the solid-liquid ratio is 1:20;extraction time is 120min; extraction temperature is 66℃;pH is 9;ultrasonic power is 500 W and ultrasonic time is 20min.After purifying oat bran polysaccharide by DEAE-52 and SephadexG-100, determining its purity by the latter,and then analyzing the primary structure of the purified polysaccharide of oat bran by UV spectroscopy (UV),Infrared spectroscopy (IR),gas chromatography (GC) and scanning electron microscopy (SEM),it reaches a conclusion that the purified polysaccharide of oat bran may not contain protein and nucleic acid, but it surely contains β- glycosidic linkage. β- glycosidic linkage consists of ribose,rhamnose, arabinose,mannose,glucose,galactose,whose molar ration of each monosaccharide is 0.21: 1:11.24:0.82:0.29:77.79.These unshaped polysaccharide is scattered in flake-like or clastic form and has a relatively smooth surface.Through the study of stability of oat bran by differential scanning calorimetry(DSC),it turns out that the structure of polysaccharides will change if the temperature is between 200℃ and 240℃.In addition,the test for vitro antioxidant of oat proves that the enhancement of total reducing power of oat bran polysaccharide can improve the clearance of superoxide anion radical (O2-·) and DPPH.However, it does not have a great influence on clearance of the hydroxyl radical (·OH).Through the research on hypoglycemic effect of oat bran polysaccharide,it can be seen that oat bran polysaccharide can alleviate the symptoms of "polydipsia, polyuria, and more food and weight loss" for the mice who suffer from diabetes. And it can also greatly improve glucose tolerance in diabetic mice as well as normal mice and effectively enhance superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) activity and decrease malondialdehyde (MDA) content inside the body.Meanwhile, the index of spleen, kidney, pancreas all increase.As oat bran polysaccharide only contributes to lowering blood glucose of diabetic mice and makes no significant effect on normal mice’s weight,water intake,food intake,blood glucose level,and glucose tolerance,this indicates that oat bran polysaccharide has no effect on normal mice.When three percent of oat bran polysaccharide is added to the milk powder for the middle-aged and elderly people,there isn’t obvious difference of such powder on the acidity and protein content. Besides, the sensory property is also better than that of powder without oat bran polysaccharide.