ZHANG Lin-song, GAO Wan-ping, SONG Yue-fan, REN Dan-dan, LIU Shu, CONG Hai-hua, WANG Qiu-kuan, HE Yun-hai*
College of Food Science and Engineering, National Research & Development Branch Center For Seaweed Processing, Key Laboratory of Aquatic Product Processing and Utilization of Liaoning Province, Dalian Ocean University, Dalian 116023, China
Abstract: In this study, the optimal separation resin of crude fucoidan (UPS-FUC) prepared from sporophyll of macroalga Undariapinnatifida Suringar by enzymatic hydrolysis was screened from 11 kinds of resins by static adsorption and dynamic elution experiments, the total sugar content and sulfate content of each component was determined by phenol-sulfuric acid method and gelatin-BaCl2 method in order to explore the separation and purification effect of different resins on the crude fucoidan sulfate of the macroalga. The monosaccharide composition of each purified component was determined by high performance liquid chromatography, Fenton reaction detection method and o-benzene. The antioxidative activity of each purified component was determined by triolol oxidation to evaluate the composition and antioxidant capacity of each component after separation and purification. The results showed that the best separation resin was D315 and five components were separated and purified by D315 resin from the fucoidan at the optimum pH of 8.0, with the yield of 14.90%, 11.45%, 17.21%, 13.54% and 12.67%, respectively,and the mass fractions of polysaccharides of 69.95%, 63.47%, 46.98%, 47.80%, and 44.45%, respectively. The analysis of scavenging ability of the five component polysaccharides for hydroxyl radical (·OH) and superoxide anion radical revealed that each component had a certain ability to scavenge both free radicals when vitamin C(VC) was used as a control. The minimum IC50 value of fraction 1(F1) was 1.13 mg/mL for inhibition of ·OH and 2.95 mg/mL for inhibition of with proportional antioxidant activity to the content of polysaccharides in the components and the fucose and galactose contents. The findings provide a theoretical reference for the separation, purification and activity study of crude polysaccharides from the sporophyll of the macroalga Undariapinnatifida Suringar.