磷酸化裙带菜多糖的制备及结构表征和生物活性分析  

Preparation,Structural Characterization and Biological Activity of Phosphorylated Polysaccharide from Undaria pinnatifida Suringar

作　　者：李瑶 熊彩明 张佳乐 冯学珍[1] 冯书珍 LI Yao;XIONG Caiming;ZHANG Jiale;FENG Xuezhen;FENG Shuzhen(School of Medicine,Guangxi University of Science and Technology,Liuzhou 545006,China;School of Science,Guangxi University of Science and Technology,Liuzhou 545006,China)

机构地区：[1]广西科技大学医学部,广西柳州545006 [2]广西科技大学理学院,广西柳州545006

出　　处：《食品科学》2024年第7期35-42,共8页Food Science

基　　金：国家自然科学基金青年科学基金项目(32001208);广西科技基地和人才专项(桂科AD20159063);广西自然科学基金项目(2023GXNSFBA026053);国家级大学生创新创业训练计划项目(202310594022);博士基金项目(校科博17Z05)。

摘　　要：以磷酸盐作为交联剂对分离纯化的裙带菜多糖进行磷酸化修饰,综合运用紫外吸收光谱、傅里叶变换红外光谱、基质辅助激光解吸电离飞行时间质谱、高碘酸氧化及Smith降解法、刚果红实验、β-消去反应、碘-碘化钾实验进行结构表征,并评价修饰前后的自由基清除能力和降血糖活性。结果表明:磷酸根的取代度为9.26,在1216、886 cm^(-1)处出现P=O、P—O—C磷酸基团特征吸收峰,表明磷酸化修饰成功;磷酸化裙带菜多糖的最大相对分子质量为94.4×10^(3),具有三股螺旋结构,是β-糖苷键连接的吡喃型葡聚糖,其中,多糖与氨基酸主要通过—O—型糖肽键相连;单糖之间的连接方式主要为1→3、1→2,1→4和1→6型糖苷键,物质的量比为0.494∶0.504∶0.002,且具有分支结构;磷酸化修饰后的裙带菜多糖对1,1-二苯基-三硝基苯肼自由基、超氧阴离子自由基(O2-·)和羟自由基(·OH)的清除率及α-葡萄糖苷酶的抑制率分别比修饰前显著提高34.76%、12.30%、76.05%和3.70%(P<0.05),说明磷酸化修饰对裙带菜多糖自由基清除能力和降血糖活性具有促进作用。The polysaccharide purified from Undaria pinnatifida Suringar was phosphorylated using phosphate as a cross-linking agent.The structure of the phosphorylated polysaccharide was characterized by ultraviolet(UV)absorption spectroscopy,Fourier transform infrared(FTIR)spectroscopy,matrix-assisted laser desorption/ionization mass spectrometry(MALDI-MS),periodate oxidation and Smith degradation,Congo red test,β-elimination reaction,and iodine-potassium iodide test,and the free radical scavenging capacity and hypoglycemic activity of the raw and modified polysaccharide were evaluated.The results showed that the substitution degree of phosphate was 9.26,and the characteristic absorption peaks of P=O and P–O–C appeared at 1216 and 886 cm-1,indicating that the phosphorylation modification was successful.The maximum relative molecular mass of the phosphorylated polysaccharide was 94.4×10^(3).It had a triple-stranded helical structure and was composed of glucopyranose unis linked together byβ-glycosidic bonds.The polysaccharide and amino acids were linked together mainly by–O–glycopeptide bonds.The main linkages between monosaccharides were 1→3,1→2,1→4 and 1→6 glycosidic bonds,the molar ratio was 0.494:0.504:0.002,and the sugar chain had a branched structure.The scavenging capacity against 1,1-diphenyl-2-picrylhydrazyl(DPPH)radical,superoxide anion radical(O2-·)and hydroxyl radical(·OH)and theα-glucosidase inhibitory activity of the polysaccharide were significantly increased by 34.76%,12.30%,76.05%and 3.70%after the phosphorylation modification(P<0.05),indicating that phosphorylation modification enhanced the free radical scavenging capacity and hypoglycemic activity of the polysaccharide from Undaria pinnatifida Suringar.

关 键 词：磷酸化 裙带菜多糖 结构表征 生物活性 

分 类 号：TS255.1[轻工技术与工程—农产品加工及贮藏工程]