Extraction, Separation And Physical And Chemical Properties Of Scallop Polysaccharides

As a kind of economic shellfish,Patinopecten yessoensis has higher nutritional value both in its scallop adductor and scallop skirt.In this paper,four kinds of polysaccharides were isolated from scallop adductors and skirts by using two polysaccharide extraction and separation technologies: enzymatic-ultrafiltration(HM)and hot-water ultrafiltration(WM),named as enzymatic-ultrafiltration scallop skirt polysaccharide(HMS),hot water leaching membrane scallop skirt polysaccharide(WMS),enzymatic-ultrafiltration scallop adductor polysaccharide(HMA),and hot-leaching-ultrafiltration scallop adductor polysaccharide(WMA).The extraction and separation process was optimized by response surface methodology,the physiochemical properties and the antioxidant activities of the isolated polysaccharides were analyzed.At the same time,the effects of different storage conditions on the physicochemical properties of the polysaccharides were studied,which provided a theoretical basis for the efficient development and comprehensive utilization of P.orientalis scallops.The main experimental results are as follows:1.The content of protein,fat and polysaccharide in scallop adductor and scallop skirt were 68.86±3.81% and 62.69 ± 3.36%,2.27 ± 0.09% and 6.53 ± 0.06%,11.82 ± 0.95% and 3.80 ± 0.76%,respectively;The ratio of essential amino-acids to total amino-acids was 33.48% and 32.88%,respectively.It can be seen that Patinopecten yessoensis has higher nutritional value both in its scallop adductor and scallop skirt2.According to the results of single-factor experiments,the extraction technology parametres were optimized with response surface methodology.The results showed that the optimal process for extraction of polysaccharides from scallop skirt hot water extraction method was as follows: ratio of materil to liquid 1:3,extraction time 4.5h,extraction temperature 90°C;The optimum extraction process of polysaccharides from scallop adductor by hot-water method is: ratio of material solvent 1:3,extraction time 6 h,extraction temperature 95°C;The optimum conditions for enzymatic extraction of polysaccharides from scallop skirt were as follows: papain,p H 7,enzymolysis temperature 55°C,material-liquid ratio 1:3,enzymolysis time 4 h,enzyme dosage 0.3% to fresh weight;The optimum conditions for extracting polysaccharides by enzymatic hydrolysis from scallop adductor were: papain,p H 7,enzymolysis temperature 55°C,material-liquid ratio 1:3,enzymolysis time 5 h,and enzyme amount 0.3% to fresh weight.3.The polysaccharides were further purified by membrane separation(10k Da and 30 k Da)to obtain four polysaccharides: WMS,WMA,HMS and HMA.The purity of the polysaccharides was increased by 4.4%,20.1%,3.9%,and 7.4% after being separated by a 30 k Da membrane.The purity of scallop adductor polysaccharides was significantly higher than that of the scallop skirts.The infrared spectra showed that HMS,HMA,WHS,and WHA all contain the characteristic groups of polysaccharides(-OH,-NH,-COOH,etc.),uronic acid,and ?-pyran ring.According to results of DSC spectra,the structure and composition of polysaccharids extracted by different methods of the same kind of raw materials are similar.Based on the HPLC chromatography of PMP derivatives,known that both scallop skirt and shell adductor polysaccharids contains mannose(Man),glucuronic acid(Glc UA),galacturonic acid(Gal A),glucose(Glc),galactose(Gal),arabinose(Arb),and fucose(Fuc).scallop skirt polysaccharide contains glucosamine(Glc N),while scallop adductor polysaccharide contains rhamose(Rha).4.The DPPH radical scavenging rate,ABTS free radical scavenging rate and hydroxyl radical scavenging rate of the skirt polysaccharides were similar to Vc,indicating that the antioxidant capacity of scallop skirt polysaccharide was higher than that of scallop adductor polysaccharide.The antioxidant activity of polysaccharide extracted by enzymatic hydrolysis is higher than the polysaccharides extracted by hot water method.5.The storage conditions affected the extraction rate and purity of scallop skirt and scallop adductor polysaccharides.The extraction rates of fresh scallop skirts and shell adductor polysaccharides were the highest,1.05% and 5.65%,respectively,which were higher than the frozen skirts(0.81%),shell adductors(3.90%),refrigerated skirts(0.58%),and shell adductors(3.05%)minimum;the purity of fresh scallop skirts polysaccharides and adductor polysaccharides was 6.4% and 50%,respectively,higher than the frozen skirt(6.0%),shell adductor(39.9%),refrigerated skirt(4.6%),and shell adductor(33.3%);According to the infrared spectra and DSC spectra,the structures and thermodynamic properties of the polysaccharides have little change,but it can be seen from the HPLC chromatograpy of PMP derivatives showed that the storage conditions have a greater impact on the scallop skirt polysaccharide components,but the scallops The components of the adductor polysaccharide are less affected.