钙离子、酸诱导的凉粉草多糖凝胶特性及其形成机理

Gelation properties is one of the important biological function of polysaccharide. The gel properties of Mesona chinesis polysaccharide are similar to commercial pectin. However, the gel forming mechanism of Mesona chinesis polysaccharide is still unknown. In our early study, we have found Mesona chinesis polysaccharide can be induced by calcium ions, acid, and the formation of the gel properties of Mesona chinesis polysaccharide is different, but the mechanism is still unknown. In this study, the molecular chain conformation and microstructure of Mesona chinesis polysaccharide formation and transition induced by calcium ions, acid during sol-gel transition process and gel evolution will be tracked at molecular level by modern instrumental analysis combination of the relevant theories and methods of the polymer physics. Furthermore, the dynamic changes of gel properties such as gel network, texture, rheology will also be studied. On this basis, through comprehensive analysis of correlation of molecular chain parameters, microstructure and gel properties parameters of Mesona chinesis polysaccharide induced by calcium ions, acid. To explore its gel formation from the view of the molecular chain conformation of polysaccharide and also to expound the relation between molecular chain conformation, microstructure evolution and gel formation properties of polysaccharide. Thus, the mechanism of the gel formation of Mesona chinesis polysaccharide could be revealed.

凝胶化性质是多糖的重要生物功能，凉粉草多糖的结构特征与商业果胶类似，具有典型果胶的凝胶特性，但对其凝胶形成机理知之胜少。前期研究中，申请人发现钙离子、酸能诱导凉粉草多糖凝胶形成，并且形成的凝胶特性差别很大的现象，但相关机理尚未见报道。项目拟采用现代仪器分析与高分子物理的相关理论和方法相结合在分子水平上研究钙离子、酸诱导下凉粉草多糖溶胶-凝胶转变历程多糖分子链构象、微观结构形态的转变，考察多糖凝胶微观结构特征、质构、流变学等凝胶特性的动态变化。在此基础上通过对钙离子、酸影响下的凉粉草多糖的分子链参数、微观结构和凝胶特性参数进行相关性分析。从凉粉草多糖的分子链构象等角度探讨其对凝胶形成的影响, 阐述多糖分子链构象、微观结构演变和凝胶性质形成特性这三者之间的关系，进而阐明钙离子、酸诱导凉粉草多糖凝胶形成的机制。

凝胶化性质是多糖的重要生物功能，凉粉草多糖的结构特征与商业果胶类似，具有典型果胶的凝胶特性，但对其凝胶形成机理知之胜少。研究发现钙离子、酸能诱导凉粉草多糖凝胶形成，并且形成的凝胶特性差别很大的现象。结果表明：凉粉草多糖浓度在3%时，表现出弱凝胶特性，钙离子（3-9 mM）的加入可以显著提高凉粉草多糖的凝胶特性，钙离子、酸诱导下凉粉草多糖溶胶-凝胶转变历程多糖分子链构象、微观结构形态的转变，研究了多糖凝胶微观结构特征、质构、流变学等凝胶特性的动态变化。采用松弛模量的流变学方法对凉粉草的凝胶机理进行分析，其结果表明，氢键作用在凝胶形成过程中起到主要作用，此外，钙和凉粉草多糖上的羧基形成的“钙桥”在凝胶形成过程中起到重要作用。阐明钙离子、酸、高压微射流均质处理诱导凉粉草多糖凝胶形成的机制及其调控机制。本研究相关研究发表论文13篇(SCI一区8篇），申请人入选万人计划人选，培养研究生4名，为进一步凉粉草多糖在凉粉制品食品加工中的应用提供基础数据与理论依据，对指导凉粉草凝胶的应用具有实际意义。