多孔淀粉多尺度空间架构定向设计机制及行为评价

多孔淀粉(PSGs)通常是经多种酶协同解构淀粉颗粒而获得的安全绿色多孔材料。但因PSGs结晶程度及晶化取向遭非均一性破坏，导致其拓扑微结构的强度及结构韧性下降，限制了其在多体系产品化的应用性能。本项目利用淀粉蔗糖酶特异的转糖基定向修饰作用，研究对不同微结构PSGs糖链大分子多尺度空间架构的调控机制，探究表观固化PSGs（即mPSGs）对典型功能物的内吞包载效果及可控释放规律。研究内容：1)研究底物-产物定向转化途径，明确动态催化过程中mPSGs的构建机制；2)研究mPSGs微纳米结构特性，阐明靶向转糖基表观固化的分子机理；3)研究mPSGs纳米力学特性，揭示多尺度结构与理化稳定性的构效关系；4)应用mPSGs体系内吞包载风味物质，考察其多场力协迫适应性和多维度可控释放规律。最终，建立PSGs多尺度空间架构定向调控机制，为淀粉糖链大分子精准修饰及功能物可控载释提供理论依据和实践例证。

Porous starch granules (PSGs), derived from natural starch, are normally obtained by enzymatic hydrolysis using the synergistic action of the amylases. PSGs exhibit various advantages in foods , e.g., non-toxic and environmentally friendly, etc. However, this type of starch lacks the structural stability, which attributes to the heterogeneous degradation of crystallites and the loss of granular integrity. This drawback limits the application of PSGs in various systems. In this project, directional modification of specific transglycosyl from amylosucrase on multi-scale spatial structure of PSGs sugar chain with controllable microstructure will be researched. Then, the modified PSGs (mPSGs) will be applied to encapsulate the functional ingredients and the control-release of encapsulated components will be evaluated. Based on the study of catalytic pathway of amylosucrase, the formation mechanism of mPSGs will be revealed. In addition, the project will explore the multi-scale structures of mPSGs, clarifying the molecular mechanism for the stabilization of mPSGs. The nanomechanics properties of PSGs under multi-scale structures, as well as the granular stability, will be investigated, providing a new insight of structure-function relationship. The mPSGS will be utilized to encapsulate selected flavors, followed by the assessment of the stability of encapsulated flavors under various conditions as well as their releasing patterns. The present study tends to set up a mechanism that can be utilized to regulate the multi-scale structures of PSGs with desired purpose. The results also provide theoretical basis and practical evidence for the precise modification of starch-based materials and for the encapsulation and controllable release of functional ingredients.