Sulfation Of Citrus Pectin By Pyridine-sulfurtrioxlde Complex In DMSO And Its Bioactivity

Citrus pectin is adopted in this research because of its simple, repeatable structure and wide source. Citrus pectin (CP), was firstly sulfated with the pyridine-sulfur-trioxide complex in dimethylsulfoxide (DMSO), and prepared sulfated samples by two methods, optimized the conditions of temperature. The coagulation effect, the path of blood coagulation and the mechanism has also been analyzed.We found degradation occurred in branched chain (rhamnose) and the main chain (galacturonic acid) of the samples of two methods. With the increased sulfation time, the degree of degradation rose, and the molecular weight gradually decreased. The molecular weight of TBA-3and DMSO-3was only47KDa and60KDa, significantly lower than the native polysaccharides. The system of DMSO sulfate content is slightly higher than the system of associates, SD-3, ZD-3respectively31.49%,23.98%, ST-3, ZT-3were29.81%,19.43%respectively.The effects of the sulfated CP on anticoagulant activity were examined by measuring the activated partial thromboplastin time (APTT), doubling APTT at concentrations of51.96IU/mg (TBA-3) and1.03IU/mg (DMSO-3), The results also showed that the sulfated pectin prolonged APTT and TT effectively, and lack of prolongation effect of the sulfated pectin on PT, which suggested the sulfated pectin inhibition of the intrinsic and/or common pathway. Compared with anti-FⅡa experiment mediated by HC Ⅱ, TBA-3was more significantly influenced on EⅡa inactivation by AT-Ⅲ, which indicated TBA-3achieved inactivation of FⅡa mainly by HC Ⅱ.The IR spectroscopies showed all the samples had been combined with sulfate group. For the both resources, compared with the citrus pectin, the changes in the shift of the signal of atom C-3, C-2to a lower field and the shift of the signal of atom C-1, C-4to a higher field demonstrated the presence of sulfate group at the C-2, C-3atom. Compared the samples, SD-3presented preliminary differentiation of signal peak, and weakening signals of other sugar but strengthening ones of galacturonic acid, but for ST-3, the results carried on the retentions of some signals of monosaccharide, which may led by the mild reaction environment.On the inhibition of Staphylococcus aureus and FRAP determinations, there wasn’t showed significant improved on the bacteriostatic test. Antioxidant capacity of the sulfated pectin samples had been enhanced than before.