The Purification, Structure Characteristics And Biological Activities Of Exopolysaccharide From Culture Broth Of Pleurtus Spodotecus Fr.

This thesis mainly investigates the physicochemical properties, structure characteristics, anti-tumor activity, hypoglycemic effect and anti-complementary activity of exopolysaccharide produced from Pleurtus spodotecus Fr..The homogeneous exopolysaccharide PSEPS2-A was extracted from the the culture broth of Pleurtus Spodotecus Fr., which was treated by Savage method, H2O2 and purified with Sephadex gel filtration chromatography to get the PSEPS2-A. The physicochemical properties and structural characteristics of PSEPS2-A were illustrated in terms of total sugar content, protein content, elements composition, molecular weight, monosaccharide composition, UV and IR spectrum, etc. In addition, we also studied the conformation of PSEPS2-A by Steric exclusion chromatography-multi angle laser light scattering(SEC-MALLS) and scanning electron microscopy (SEM).The anti-tumor activity of PSEPS2-A in vitro on four cell lines of Hela, HepG2, A549, and MKN-45 is also discussed in the method of MTT. It turns out that PSEPS2-A could present relatively higher anti-proliferative activity against HepG2 cells and good concentration dependence than other cell lines. Furthermore, the anti-tumor activity in vivo of PSEPS2-A is evaluated by intraperitoneal administration of S180 tumor-bearing into mice which later will be treated with PSEPS2-A in different doses. As a result, in a proper concentration (100 ug/kg/d), PSEPS2-A has anti-tumor effect by significantly inhibiting the growth of the S180 transplanted tumors, enhancing phagocytosis ability and improving the serum cytokine content of the tumor-bearing mice. Moreover, diabetic mice models induced by Alloxan were continuously intragastric administered with different doses of PSEPS2-A. The results shows that PSEPS2-A could significantly reduce the contents of fasting blood glucose (FBG), promoted the liver glycogen synthesis and elevated the levels of glucose tolerance, for achieving the hypoglycemic effect. However, PSEPS2-A did not have anti-complementary activity.