The Study On Antioxidant Activity And Antidiabet Acctivity Of Polysaccharide Hydrolysate From Auricularia Auricula

In the early stage of this thesis,the production of Auricularia auricula polysaccharides,extraction process and other conditions were selected,and its structural function was preliminarily explored.In the previous experiments,simulated gastrointestinal acid hydrolysis could significantly increase the antioxidation and hypoglycemic activity of Auricularia auricula polysaccharide.The antioxidant and antidiabet acctivity of the polysaccharide after acid hydrolysis was explored on the basis of previous experiments.1.Optimization of the polysaccharide hydrolysate from Auricularia auricula with antioxidant activity by response surface methodology.The ABTS· scavenging ability of AAPs-H was 97.94±0.87% by the acid-hydrolysis conditions,hydrolyzing time 166.8 min,hydrolyzing temperature 95.04? and the acid concentration 14.03mol/L,which was well matched with the predicted value(99.77%)of the BBD model.2.Through Sephadex G-10,AAPs-F was a heteropolysaccharide and comprised of glucose,galactose and fucose with the molar ratio of 50 : 1 : 2.Ultraviolet scanning and indene triketone proved that AAPs-F did not contain protein.According to the 13C-NMR AAPs-F composed of three different monosaccharide residues.The primary key of their molecules was a c-6?-Glc(1?4)-and ?-Glc-glycosidic bond.And there may have ?-Glc(1?4)-,?-xyl(1?4)-,?-xyl(1?3)There is a c-6 ?-Gal(1-4)-glycosidic link containing amino and acetylated oligosaccharides.3.AAPs-F showed a remarkable protective effect to the injury induced by hydrogen peroxide(0.1M)or methylviologen(concentration 83.33 mg/mL)(P<0.01),and it could up-regulate stress-resistance related enzymes SOD by 109.74% and CAT by 106.84% in C.elegans.Aap-f can enhance the oxidative stress of nematodes.Both AAPs and AAPs-F can prolong the life of the worm in the high-sugar environment(sucrose concentration of 1000mmol/L).4.In the T2 DM animal model,AAPHs and AAPs can significantly improve the activity of antioxidant enzyme CAT,GR and GSH in serum(P < 0.01).AAPs-F improve CAT enzyme activity was significantly better than AAPs.AAPHs can significantly reduce MDA level in serum after 4 weeks treatment of AAPs and AAPHs(p < 0.05),blood sugar levels fell 25.9% and 23.7% respectively.AAPs and AAPs-H can significantly improve T2 DM model of rat liver glycogen level(p < 0.05,p < 0.01).It is indicated that AAPHs has good antioxidant activity,which can provide evidence for further development.