Purification, Sulfation And Antioxidant Activity Of Polysaccharides From Cirsium Setosum

Cirsium setosum is a kind of new edible and medical potherb inrecent years.It contains rich biological active components and exhi-bits diverse bioactivities so that it is exactly important to extractand purify its active components. Polysaccharides are widely distr-ibuted in the world,mainly obtained from plants, animals, microorga-nisms and so on.By previous pharmacological studies,they have be-en reported as an immune modulator to play a wide range of functi-onal roles in antitumor,anti-virus,anti-infective,anti-oxidation andthe regulation for blood glucose and lipids.On the basis of their lowtoxicity, more and more concerns have recently been paid to thecorrelative research with bioactive polysaccharides in the modernmedicine and food industry field.However, there are few reports ab-out the polysaccharides from Cirsium setosum. Based on the medi-cal value and edible value of the traditional Chinese herbal medicineCirsium setosum as the experimental materials, which studied onextraction, isolation, purification, the method of sulfation and antio- xidat activity of polysaccharides from Cirsium setosum. The main r-esults were as follows：1. The experiment adapt the Soxhlet extraction to remove oilfrom Cirsium setosum powder, then used the meathod of heatingand ultrasonic to extract polysaccharide compound. And its conte-nt is determined by the anthrone-sulfuric acid method.The oil remo-ving rate of the polysaccharides from Cirsium setosum was7.925%,the yield of the polysaccharidees was6.43%.Using other methods,such as the Sevag Method and the Method of Trichloroacetic Acid,to remove protein, in order to get the pure polysaccharides.The rateof removing protein was70.52%and73.01%,while the rate of losingpolysaccharides was16.29%and29.74%.By contrast, the Sevag M-ethod was the better choice to remove protein. Three kinds of poly-saccharide,named as CSPS-Ⅰ,CSPS-Ⅱ,CS-PS-Ⅲ, are precipitated bythe55%,75%and95%ethanol, and the extraction yields of polysa-ccharides were5.75%,7.01%and8.67%.2. The experiment used four kinds of macroporous resins, suchas D101, D4020, AB-8and X-5, to select the best candidate, whichusing the dynamic and static adsorption experiment to adsorb anddesorb polysaccharides. The results of experiments reveald that A-B-8was optimum macroporous resin for purificating Cirsium setos-um polysaccharide. And the dynamic experiment is better than sta- tic. Based on those experiments, the optimum technology conditi-ons were as follows: sample concentration was2mg/mL, samplevolume was20mL, flow velocity was2.0mL/min and pH value ofeluent was7.3. The experiment applied the method of sulfation to chemical-ly modified for CSPS-Ⅰp,CSPS-Ⅱp,CSPS-Ⅲp, and substitution degr-ee is0.47,0.43,0.54, respectively.The antioxidant activities of poly-saccharides of sulfation was studied and compared with polysacch-arides without modification,the results of antioxidative experimentsreveald that the polysaccharides from Cirsium setosum had some fun-ctions of scavenging free radicals.And it presented dose-effect relat-ionship. One aspect, the best antioxidant activity of eliminate hydr-oxyl radical and nitrite ion was obtained by sulfated polysaccharide-es, followed by pure polysaccharides, and the antioxidant activity ofeliminate hydroxyl radical and nitrite ion of crud polysaccharideswas the weakest.And the antioxidant activity of eliminate superox-ide anion was obtained by crud polysaccharides, pure polysacchari-des and sulfated polysaccharides were almost the same, relatively,the antioxidant activity of eliminate superoxide anion by pure polys-accharides was higer than by crud polysaccharides. Another aspe-ct, the antioxidant activity of75%fraction was better than55%,andthe95%fraction was the best.