The Extraction, Purification And Sturcture As Well As Bio-activities Of Sulfated Polysaccharide From Corallina Officinalis

Corallian officinalis, belongs to the Rhodophyta (Rhodophyta) the real Rhodophyta subclass (Florideae), is widely eaten in China and many other countries. In this paper, chemical characteristics and chemical structure of two polysaccharides (F1,F2) were determined, and some biological activities had also been researched.The following results were achieved.1. Two methods were progressed to extract the polysaccharide, one is the common water extraction, the other is new type of buffer, enzyme assisted extraction.The results indicated that yield of polysaccharide using new type was5%, and the content of protein was only1.67%because of adding a papain during the extraction process,but polysaccharide yield with the traditional water extraction was merely2.5%, in addition,protein content of the polysaccharide was up to17.44%, which still needed to remove proteins in subsequent experiments. So it seems that the new buffer, enzyme assisted extraction owned not only the higher yield,but lower protein content and simpler program, was an ideal method of the polysaccharide extract.Then the polysaccharide was purified by a DEAE-Sephadex A-25column eluting with a step gradient of0.1-2M NaCl.and used the phenol-sulfuric acid method to determine the total sugar content of the elution,got a suitable concentration of NaCl.Fl and F2were obtained by stage eluting. The fractions of purity were identificated by four methods.the Superdex-200,Sephacryl S-300column chromatography,HPLC and UV. Figures appeared as only a single and symmetrically sharp peak, which indicated the two fractions were homogenous polysaccharides.2. Phsico-chemical characteristics of F1and F2were analyzed and determined by chemical methods.The total sugar content of Fl and F2was estimated as44.54%,42.50%. Protein content in F1and F2were1.44%,1.31%by coomassie Brilliant blue method and the sulfate content of Fl and F2were42.88%,43.29%.The molecular weight of F1and F2were determined by gel filtration and found to be15.8×104Da and24.7×104Da. The results demonstrated that the polysaccharides (F1and F2) were high sulfated polysaccharides. Solvolytic desulfation of F1and F2 removed87%of the sulfate, prepared for the study of next polysaccharide structure, denoted as the D-F1, the D-F2respectively.3. The structure of F1and F2were analyzed and determined by GC、FI-IR and GC-MS techniques. The results showed that the two sulfated polysaccharides both only contained xylose and galctose, but had different molar ratio for F1and F2. Galctose was the main sugar unit, accounting up to94.37mol%,97.27mol%, but the proportion of xylose was small to5.63%,2.73%. IR spectrum demonstrated several bands corresponding to sulfate and carboxy group, which was consistent with the results of chemical methods. The results of GC-MS showed F1contained a linear backbone built up of1�'4Xyl,1�'3Gal residues. This backbone had braches at position2-O of Xyl,6-O of Gal,the terminal residues were Gal,Xyl.4. Antioxidant activities of the four polysaccharide fractions (F1,F2,D-F1,D-F2) were evaluated by assays of various antioxidants in vitro systems, including superoxide anion, DPPH and hydroxyl radical-scavenging activity and reducing power.The results showed Corallian officinalis polysaccharide showed strong antioxidant capacity in scavenging hydroxyl radical system with a significant dose-effect relationship.what’s more, sulfated polysaccharide fractions possessed good antioxidant properties and had higher antioxidant abilities than de-sulfated polysaccharides,and the the antioxidant capacity of the Fl was slightly higher than the F2. Therefore, that date suggested that the correlation between the sulfate content, molecular weight and antioxidant activity was positive. Perhaps the antioxidant activity was also related with the structure of the polysaccharide, and its mechanism needed to be deeper exploration.5. In this experiment, chose the GB Pharmacopoeia drug the hygroscopicity trials guiding principles as the standard. Five polysaccharides fractions (WCP-1,F1,F2,D-F1,D-F2) of moisture-absorption and-retention capacities in vitro had been studied under different humidity wih weight measuring compared to glycerol and chondroitin sulfate. The results revealed that the moisture-absorption function of WCP-1was significantly higher than the other four components, and the absorption rate showed an upward trend,up to82.29%,even higher than the reference substance glycerol and chondroitin sulfate under the relative humidity of83%and41%in60hours, moisture-retention experiment showed that the moisture-retention rate of WCP-1was slightly lower than the glycerol under the dry silica gel and41%humidity conditions.The results indicated that Corallian officinalis polysaccharide had a certain degree of stability, long-lasting moisturizing properties,which could be used as a daily cosmetic moisturizers, product development and utilization.