Study On Extraction And Purification Of Tremella Polysaccharide And Its Protective Effect On Ulcerative Colitis In Mice

Ulcerative colitis is a global chronic inflammatory disease,which is usually accompanied by oxidative stress injury with the development of inflammation.Therapeutic drugs have different side effects on different patients,which is not conducive to the health of the body.Studies have shown that Tremella polysaccharides,as a natural active substance,have no adverse effects on the human body,and have biological functions such as anti-inflammatory,antioxidant,anti-tumor and anti-aging.However,at present,studies on deproteinization methods suitable for Tremella polysaccharides are relatively There are few studies on the effects of Tremella polysaccharides on ulcerative colitis.It is not clear whether the Tremella polysaccharides have a protective effect on ulcerative colitis.In this study,Tremella polysaccharides?TPS?were extracted from Tremella polysaccharides by water extraction and alcohol precipitation,followed by Sevage,Ca Cl₂,Ca Cl₂-enzyme complex,Na Cl,enzyme and trichloride Acetic acid?TCA?method for deproteinization,and optimize the process conditions of Ca Cl₂-enzyme complex deproteinization process that has been screened to obtain a Tremella polysaccharide with high sugar content,low protein content and good antioxidant activity.The obtained Tremella polysaccharides were eluted and separated by DEAE-52 ion exchange column.By pre-administering Tremella polysaccharides to mice and constructing an ulcerative colitis model,we further explored whether the Tremella polysaccharides have protective effects on ulcerative colitis.the result shows:1.The water extraction and alcohol precipitation method can effectively extract the Tremella fuciformis crude polysaccharide from the Tremella fuciformis fruit body,and the sugar content reaches 76.5%.Six common deproteinization methods can remove the protein in Tremella fuciformis.After deproteinization,the protein content of Tremella polysaccharide varies from 5.9%to 2.28%.Among them,the Ca Cl₂-enzyme compound method has the best deproteinization effect,and the protein content is only 2.28%.Tremella polysaccharide obtained by Ca Cl₂-enzyme complex deproteinization had the highest uronic acid content of17.37%.At the same time,it has good hydroxyl radicals,DPPH scavenging ability,and ABTS scavenging ability is superior to TCA method,enzymatic method and Sevage method three deproteinization methods,reducing ability is better than TCA method,enzymatic method and Na Cl method.2.The optimal deproteinization process conditions obtained by optimizing the Ca Cl₂-enzyme complex deproteinization process conditions through single factor and orthogonal experiments are:adjust the p H to 8.0,heat to 85?,add 3%Ca Cl₂,cool and centrifuge to remove Clear,adjust the p H to 6.0,add 2%enzyme,enzymolysis at 50?for 2.5h,kill the enzyme by boiling water for 10 min,cool down and centrifuge to take the supernatant.After deproteinization under these conditions,the soluble sugar content of the crude polysaccharide increased from 76.5%to 80.4%,the protein content decreased from2.28%to 1.26%,a decrease of 44.7%,and the uronic acid content was 18.59%.3.Na Cl was used as the eluent to separate and purify the Tremella polysaccharides obtained by Ca Cl₂-enzymatic deproteinization through a DEAE-52 ion exchange column.The concentration of 0.5 mol/L eluent was good for polysaccharides.And DPPH have the highest clearance rate,and the hydroxyl radical scavenging ability and reducing ability are better.4.The molecular weight and monosaccharide composition of the purified Tremella fuciformis polysaccharide were determined,and the structure was characterized.The molecular weight of Tremella polysaccharide obtained by Ca Cl₂-enzyme complex deproteinization is 5.17×10⁴Da,which is mainly composed of mannose,glucose and a small amount of galactose,glucuronic acid,xylose and arabinose.The microstructure shows that the Tremella polysaccharides are in the form of filaments and flakes,intertwined and complicatedly connected.There are three polysaccharide characteristic peaks in the infrared spectrum,and they have uronic acid and pyranoside structures.5.Using 3%DSS to induce ulcerative colitis in male Balb/c mice,an animal model of ulcerative colitis was established.On the 6th day,there was a significant loss of blood in the stool and weight,and the modeling was successful.The results showed that Tremella fuciformis polysaccharide can significantly relieve the weight loss of mice with colitis and reduce the degree of blood in the stool of mice.It can effectively improve the clinical symptoms of colitis,in which the length of the colon is increased by 13.85%compared with the model group,and the spleen index is 11.95%lower than the model group.In summary,different deproteinization methods have a greater impact on Tremella polysaccharides.The deproteinization method suitable for Tremella polysaccharides is Ca Cl₂-enzyme compound method.Tremella polysaccharides can reduce ulcerative colitis by increasing the length of the colon and alleviating splenomegaly Clinical symptoms,protect mice with ulcerative colitis.