Extraction, Separation, Structure Analysis And Hypoglycemic Activity Of Polysaccharide From Camellia Seed Meal

Camellia seed meal is residue after pressing tea oil, containing 20%-30% of polysaccharides. Polysaccharide has various biological activities, such as anti-oxidation, enhancing immunity, lowering blood-glucose and anti-infection. So studying on extraction and exploitation of camellia seed polysaccharide has theoretical and practical significance. In this paper, camellia seed meal was used as raw materials, studying on traditional hot water extraction assisted enzymatic extraction of camellia seed polysaccharides, and also studying on the structural characteristics, the basic physical and chemical properties and hypoglycemic activity of the camellia seed polysaccharide. The main research results are as follows:Response surface methodology was used to determine the optimum enzymatic hydrolysis conditions. The results showed that the optimal conditions for the enzymatic hydrolysis were determined as below:temperature of 40?, reaction time 120min, enzyme dosage 2.0%; the orthogonal experiment was used to determine the optimum extraction conditions. The results showed that the optimal extraction conditions of polysaccharide were determined as below:extraction temperature 80?, solid-liquid ratio 1:20 (g/mL), extract 60min, under this condition, the camellia seed polysaccharide average yield of 18.48%.To make the polysaccharides further separated and purified. Raw polysaccharides was treated with Sevage method to remove the protein, with hydrogen peroxide to decolorize, with DEAE-52 cellulose column to purification, eluted with 0.4mol/L NaCl can get a homogeneous components polysaccharide named SCFP, its molecular weight 2.0121×107Da. Infrared spectroscopy showed SCFP had typical characteristic absorption peaks of polysaccharides, and there were no proteins or nucleic acids in polysaccharides through UV spectra analysis. SCFP after acetylation by GC analysis showed SCFP mainly composed of rhamnose, xylose and glucose in a molar ratio of 11.19:17.06:5.81.Studied the hypoglycemic effect of camellia seed polysaccharides on streptozotocin (STZ)-induced diabetic mice, fed a doses of 50,100 and 200mg/(kg·d) camellia seed polysaccharide,the positive control group was fed a dose of 10mg/(kg· d) of glibenclamide, the test lasted for 4 weeks. The results showed that the camellia seed polysaccharides after purification are effectively alleviate the symptoms of diabetes mice, significantly reduced blood sugar levels in diabetic mice in a dose-dependent manner, significantly reduced MDA levels of diabetic mice liver and kidney, while effectively improve GSH-PX, CAT and SOD activity of the diabetic mice liver and kidney, These results showed that hypoglycemic mechanism of camellia seed polysaccharide may by increasing the body's antioxidant enzyme activity, remove free group to release the free radical damage to the body to achieve.