Extraction, Isolation, Purification And Function Evaluation Of Polysacchrides From Pu Erh Tea

Pu'erh tea is a special black tea in China, it has a long history of drinking and exporting. As people improving the quality of life and desiring health, this tea is favored by more and more consumers.Tea polysaccharide is another important physiological active substances after tea polyphenols found. To better understand the composition of tea polysaccharide and physical activity for large-scale utilization in future. This article studied temperature, time, the ratio of solid to liquid, extraction times in processing by single factor and orthogonal tests, compared water extraction with ultrasonic extraction; separated tea polysaccharide by DEAE cellulose resin,studied their monosaccharide composition using liquid chromatography, anti-oxidation and studied reducing blood glucose.The results are as follows:1.This articles optimizes the process parameters of extracting tea poly sacc-haride. the optimal extraction parameters of water extraction was as follows: temperature was 90℃, time was 70min, the ratio of solid to liquid was 1:25, extracting one times, polysaccharide was 3.638%. the optimal extraction parameters of ultrasonic extraction was as follows:temperature was 70℃, time was 15 min, the ratio of solid-liquid was 1:20, extracting three times, polysaccharide was 3.824%.2.10 kinds of ion exchange resin and macroporous resin of tea polysaccharide decolorization were screened,the results showed that D101 resin was optimal for decolorization, the decolorization rate was 72.27%, the rate of protein removal was 71.38%, the rate of polysaccharide retention was 46.97%. the best adsorption conditions of decolorization was as follows:temperature was 50℃, resin was 11mL, pH was 4 and feed concentration was 3.8mg/mL.3. By studying the processing of separating and purifing tea polysaccharide, the results showed that:the concentration of 50% trichloroacetic acid to add volume to 2% of the sample liquid protein is better off. TPSⅠand TPSⅡwas got by divided by DEAE cellulose resin. After HPLC analysising, the mass ratio of hydrolysis products by TPSⅠwas rhamnose:glucose:sucrose:1.477:0.5923:0.3202; the mass ratio of hydrolysis products by TPSⅡwas rhamnose:glucose:sucrose:1.469:0.7414:0.3790.4. By studying the effect of tea polysaccharide hydroxyl radical and superoxide radical scavenging on the intestinal a-glucosidase, glucose metabolism in liver enzymes, and in vitro evaluation of antioxidant tea polysaccharide, reducing blood sugar. The results showed that tea polysaccharide has some effect on hydroxyl radicals and free radical scavenging, intestinal glucose a-glucosidase inhibition is weak, It can significantly enhance liver glucose kinase and several sugar kinase activity.