Antioxidant And Anti-hyperlipidemia Activities Of Residue Polysaccharides From Auricularia Auricular

The Auricularia auricular(A.auricular)is a nutrient-rich fungi for both food and medicine,which has has been cultivated on a large scale.However,the high productions of A.auricular produced a large number of abandoned residues,leading serious environmental problems including resource waste and pollutions.Hyperlipidemia is one of the major diseases that currently endanger human health without effective treatments clinically.Besides,the drugs for treating hyperlipidemia presently showed certain side effects to the health during the long-time use.Hence,it seemed important to find a natural and non-toxicity therapeutic drug for the treating and prevention against the hyperlipidemia.In present experiment,the residue polysaccharides from A.auricular(RPS)were obtained by water extraction,alcohol precipitation,deproteinization and depigmentation.The antioxidant activities and anti-hyperlipidemia activities were investigated both in vitro and in vivo.Moreover,the characterizations of RPS was also analyzed by gel permeation chromatography(GPC),Fourier-transform infrared(FT-IR),and nuclear magnetic resonance(NMR)analysis.(1)In vitro antioxidant capacities of RPS:The in vitro antioxidant capacities of RPS were estimated by reducing power values and scavenging capacities on both hydroxyl and DPPH free radicals.The results showed that RPS had antioxidant capacity and gradually increased with the increasing of RPS concentrations.(2)Animal experiments:The results showed that RPS could significantly increase activities of glutathione peroxidsade(GSH-Px),superoxide dismutase(SOD),catalase(CAT)and total antioxidant capability(T-AOC),and reduce the contents of malondialdehyde(MDA)and lipid peroxidation(LPO)in the liver,indicating that RPS can improve the oxidative stress in hyperlipidemic mice.Moreover,RPS could reduce the levels of total cholesterol(TC),low-density lipoprotein cholesterol(LDL-C),and triacylglycerols(TG),and increase the levels of high-density lipoprotein cholesterol(HDL-C)in serum of diseased mice,the lowest decrease of LDL-C reached 29.03%,indicating that RPS showed the abilities on improving the lipid metabolism in hyperlipidemic mice.Besides,the activity of Alanine transaminase(ALT),Aspartate transaminase(AST)and Alkaline phosphatase(ALP)in the serum of the diseased mice decreased by 39.06%,23.87%and 20.97%,respectively.The histopathological observations of livers demonstrated that RPS could relieve liver damage in diseased mice.Additionally,the determination of insulin(INS),adiponectin(ADPN)and leptin(LEP)levels in serum,and the oral glucose tolerance test(OGTT)showed that RPS could improve the situation of glucose intolerance and insulin resistance in hyperlipidemic mice.(3)Structural analysis of RPS:The structural properties of RPS were analyzed by gel permeation chromatography(GPC),Fourier-transform infrared(FT-IR)and nuclear magnetic resonance(NMR).The results determined that RPS was an amino-pyranose with the molecular weight of 2.00×10~5Da.The present results indicated that RPS showed strong antioxidant and anti-hyperlipidemia capacities in improving the series of physiological diseases in high-fat-emulsion-induced hyperlipidemic mice,proving that RPS had the potential in preventing and treating hyperlipidemia.The present results could provide new ideas for the research and development of natural medicines with higher anti-oxidation and hypolipidemic abilities,and provide a new method for the utilization of A.auricular residue.