Study On Extraction,purification And Antioxidant Activity Of Polysaccharides From Abalone Visceral

With the rapid development of abalone aquaculture,its processing scale also increases year by year.During the processing of abalone,large amounts of viscera are discharged.The wastes,accounting for about 30%of the total body weight of abalone.It seriously causes resource waste and environmental pollution.The abalone visceral contains many useful substances beneficial to health.There is a well exploiting foreground.In this study,we chose the abalone visceral in the sea of Fujian.Meanwhile,the improved extraction methods used in the study combined protease-hydrolysis and ultrafiltration separation technology.Furthermore,purified and investigated the functions on the antioxidant effect.The purpose was to provid scientific basic data for comprehensive utilization of abalone visceral.Main results achived in this research as follows:We selected alkaline protease for the first enzymatic hydrolysis.The single factor experiments and the response surface design experiment was used to control enzymatic hydrolysis conditions.The result showed that the best optimum processing technology was material liquid 1:39,enzyme concentration 3500 U/g,in 19 hours.In this condition,the polysaccharide extraction yield was 13.62%.The 10 kDa ultrafiltration membrane had been proved to have good functions on separation of polysaccharides and protein.The retention rate of polysaccharides was 82.11%.Then,we selected flavor protease for the second enzymatic hydrolysis.After ultrafiltration experiment,the content of abalone visceral polysaccharides was51.75%.The abalone visceral crude polysaccharides named CAVP were isolated by DEAE SepharoseCL-6B,andSephacrylS-300HR.Resultsshowedthreehomogeneous polysaccharides?AVP1?AVP2?AVP3?was obtained.AVP1 as a kind of floccules with pale yellow color contained 62.75%total sugar,10.54%protein and 7.14%sulfate.The molecular weight of AVP1 was estimated to be 14.99 kDa and the root mean square radius was 11.40 nm.The molecular conformation showed a random coil.AVP2 as a kind of powder with dark brown color contained 23.09%total sugar,36.41%protein and 1.64%sulfate.The molecular weight of AVP2 was estimated to be 58.48 kDa and the root mean square radius was 37.00 nm.The molecular conformation showed a spherical structure.AVP3 as a kind of floccules with yelow brown color contained 44.67%total sugar,19.24%protein and 4.92%sulfate.The molecular weight of AVP3 was estimated to be 39.63 kDa and the root mean square radius was 19.50 nm.The molecular conformation approximately showed a spherical structure.The configuration analysis of purified Abalone visceral polysaccharides showed monosaccharide composition of these three kinds of polysaccharides was Man,GlcN,GalN,Glc,Gal,Xyl and Fuc.The infrared spectrum proved AVP2 had more amino.AVP1 and AVP3 had more sulfate.They were all atypical absorption property of polysaccharides in a pyranose.The activity of scavenging free radicals showed that the abalone visceral polysaccharides CAVP?AVP1 and AVP3 had good activitty of scavenging DPPH free radicals.Its IC₅₀0 was 1.46mg/mL?1.74 mg/mL?1.55 mg/mL.The hydroxyl free radical scavenging activity of AVP1 were weaker than CAVP and AVP3.Its IC₅₀0 was 7.14 mg/mL?15.27 mg/mL?8.11 mg/mL.The superoxide free radicals scavenging activity of all the kinds of polysaccharides were weak.The abalone visceral polysaccharides CAVP?AVP1?AVP3 could have protective effect to LO2 cells damaged by H₂O₂ oxidation from 0.5 mg/mL to 4 mg/mL.All could improve the cell survival rate and CAVP?4 mg/mL??AVP1?0.5 mg/mL??AVP3?0.5 mg/mL?decrease the content of LDH in cell culture supernatant.CAVP highly observably increased the intracellular content of GSH-Px?4 mg/mL?,CAT?0.5 mg/mL?and SOD?0.5 mg/mL?.AVP1 had significant functions to CAT and more significant to GSH-Px and SOD at 4 mg/mL.AVP3 could significantly increased CAT?0.5 mg/mL?and SOD?4 mg/mL?.AVP1?p<0.05?and AVP3?p<0.01?could significantly reduce lipid peroxidation products.