Coltsfoot Polysaccharide Extraction And Separation And Purification Of Research

The dried buds and flowers of Tussilago farfara placed in genus Tussilago, as traditional Chinese herbal medicine in official medical prescription or folkremedy and proved recipe, are mostly used in resisting acute and chronic inflammation of the trachea,pulmonary tuberculosis, and so on. Polysaccharides are widely applied in medical field with its function of antioxidation, antitumor, antivirus,antiulcer, antimutagenic, lipid decreasing, reducing blood sugar, etc.The thesis is aimed to develop herbal resources of Southern Shannxi through researching the dried buds and flowers of Tussilago farfara. This thesis has a systematic study focused on the polysaccharide extraction, purification process including removing protein and the decolorization process. The antioxidant activity of polysaccharide is tested with preliminary analysis its structure.(1) polysaccharide extractionA new technology of extracting polysaccharide from the dried buds and flowers of Tussilago farfara was studied. The raw materials were managed by pre-soaking-ultrasonic extraction and water extraction. Based on the single-factor tests, the optimum conditions were obtained through the Response Surface Analysis. The conditions were as follows:pre-soaking time 5h, ultrasonic extraction time 33 min, water extraction time 1.5h, temperature at 77℃, ratio of raw materials and solution at 1g:10mL. The extraction rate was 19.48%.(2) Process of removing proteinBy comparing the five methods of protein removal including by hydrochloric acid, trichloroacetic acid, Sevage method, trypsin-Sevage law and papain-Sevage, papain-Sevage method was choosed as the optimal method finally. The optimum conditions were substrate concentration 1% of papain, pH 7.0, temperature 60℃, hydrolysis time 2h, repeat 3 times with Sevags method. The amount of protein removed was 88.95% while polysaccharide remained 92.63% during the deproteinization process.(3) Process of decolorizationContrasting four decolorization methods such as hydrogen peroxide oxidation method, live carbon attaching method, reverse micelle solution method and macroporous rosin adsorption method, it was macroporous rosin adsorption process that had the most effect in decolorizing polysaccharide from the dried buds and flowers of Tussilago farfara. LS-206 resin was used to determine the optimum adsorption conditions for this method. The sample was 1.5 BV with the current velocity of 2 BV/h meanwhile the sample mass concentration was 6.0 mg/mL. The decolorazation rate was about 94.20%, and the protein removal was over 97.40% in all after disposal while polysaccharide retention rate was 73.03%.(4) Study the antioxidant activity of Tussilago farfara polysaccharidesThe results showed that Tussilago farfara polysaccharides had the cleaning capability of superoxide radical,hydroxy radical, nitroso and DPPH.Especially the nitroso and DPPH had satisfied scavenging effect and the ultrasonic polysaccharides was better than polysac charides by water extraction.The more purified, the better cleaning effect of the polysaccharides had.(5) Primary structural analysisThe ultrasonic polysaccharides was purified and analysised its first-order structure preliminarily. The moleculer weight of the it was 169800Dal by Gel Permeation Chromatography (GPC). The gas chromatography (GC) showed that it was composed of mannose and galactose with the molar ratio of 1.83:1.