Sulfate Modification And Bioactivity Of Scallop Muscle Glycogen

Scallop (Patinopecten yessoensis) is an important aquatic economic species. In this study, the glycogen was extracted from the muscle of scallop and the structure was identified. Then the glycogen was sulfate modified by optimizing the process conditions. The effect of sulfatation degree and molecular weight of the sulfate modified glycogens on bioactivities were studied.Scallop muscle glycogen (SMG) was obtained from scallop muscle by proteolytic extraction, the protein was removed by protease-sevag method and freezing-thaw method. The yield of glycogen was 13.78%, and the contents of carbohydrate and protein were 91.91% and 1.08%, respectively. The molecular weight of SMG was about 430 kDa, and its monosaccharide composition was only glucose. The methylation results of SMG showed that, all the links in the monosaccharides composition were glucose, and 1,4-linked with glucose was the majority of bond type, which was the typical composition of glycogen.The scallop muscle glycogen was modified by chlorosulfonic acid-pyridine (CSA-Pyr) method, and sulfated scallop muscle glycogen (SSMG) was obtained. FT-IR spectra analysis shows the sulfated compounds trait. According to orthogonal test, reagent proportion, reaction temperature and reaction time were selected with degree of sulfatation (DS). The optimum modification conditions were the ratio of chlorosulfonic acid to pyridine of 1:5, the reaction temperature of 60 ? and the reaction time of 3 h.Six SSMG with different DS were obtained by changing sulfated condition, and its DS were 0.25,0.61,0.82,1.13,1.67 and 2.83. Compared with SMG, the sulfated modification could improve the anticoagulant, lymphocyte proliferation, anti-inflammatory and complement activities, but the anti-tumor and antioxidant activities were not affected. With the increase of DS, the above four activities were enhanced. Generally, when the DS reached to 0.82, the activities approached the stationary phase. However, when the DS was too high, the activities reduced.SMG was enzymed with amylase, then five low molecular weight sulfated scallop muscle glycogen (LSSMG) were obtained by Sephadex G-100 gel column, its MW were 21.6, 14.8,11.5,7.4 and 4.2 kDa, respectively. In this molecular weight range, anticlotting (TT value), anti-tumor and lymphocyte proliferation activities of LSSMG gradually strengthened with the increases of MW. But the anticlotting (PT and APTT value) and anti-inflammatory activities of LSSMG rose at first, then decreased. The activities of LSSMG were generally higher than SSMG, which might caused by decrease of MW.