Extraction Of Radix Isatidis Polysaccharides And Its Effects On Immunosuppressive Mice

Radix isatidis polysaccharide(RIP) is a kind of bioactive polysaccharide,which is extracted from RadixIsatidis(RI),and whose content is about12%.RIP has biological functions of strong immune regulationactivity, free radical scavenging activity and antibacterial and antivirus activity. But at present，inpharmaceutical produce process related to RI, its residues are often regarded as waste dregs, while in whichthere still are a lot of polysaccharide of not being used effectively, resulting in a waste of resources. Thisstudy is intended to extract RIP from the waste dregs, obtain the optimum condition for extracting,andsimple methods for the determinating range of polysaccharide molecular weight and study immuneregulation effects of RIP on mouse.This study is the first announcement of obtaining the RI residue through degreasing the RI powder bypetroleum and being treated with95%ethanol repeatedly, and at last, soluble substance in ether and alcoholaccount for1.17%and5.07%, respectively. The study of single factor and orthogonal test is to find weatherfactors of extraction time, extraction temperature, extraction times and ratio of material to liquid willinfluence the extraction of RIP, and whose results reveal that rate of the final RIP product is16.43%.whenextracting4times in temperature of95℃for2h each time under1:9of ratio of material to liquid.The study employs lead acetate as a precipitant of polysaccharide, which has functions of removingthe impurities and bleaching it, and then the product is separated by hollow fiber membrane. At last,employing phenol sulfuric acid method, the separated liquid polysaccharide content of each step isdetermined, and thus molecular weight distribution of polysaccharide is obtained. The result reveals theconcentration of final product is37.392mg/mL, and its mass fraction is90.8%when in range of themolecular weight of1×10~4D~1×10~5D. The result is reliable, and the used methods avoids tedious operationand experimental errors caused by the repeated separation and purification.The test mice are randomly divided into control group, model group and three groups of different dose(low, middle and high)to establish the model of immune suppression. The control and model group are fedwith basic feed while groups of different dose were fed diets containing different amounts of RIP. After sixweeks, routine indexes of blood, ratio of body weight to organ weight,IL-2and TNF-α of the test mouse aredetermined. The results show that, amounts of leucocyte/erythrocytes, blood platelets and hemoglobinincrease when the dose of crude RIP is higher. Weight of different groups decreases from the control group,the low dose group, the middle group, the high group to the model group. Ratio of body weight to organweight of the control group is higher than other groups.The levels of IL-2and TNF-α increase significantly.The results prove tahat crude RIP can improve mmune function of mouse but have a certain adverseinfluence on their growth.