皮克林样球蛋白高效稳定温度响应高内相乳液亲水凝胶及构效机理

It is a well recognized fact that many globular proteins exhibit good emulsification and emulsion stability, but to date, it still remains a debate about whether these proteins can perform as effective stabilizers for oil-in-water high internal phase emulsions (HIPEs). Recently, the applicant overcame the limitation about the knowledge about the stabilization of emulsions with globular proteins, and found that some native globular proteins are a kind of excellent Pickering nano-stabilizers for HIPEs. Based on this, this project further tries to characterize the common structural features of these Pickering-type globular proteins, and unravel the formation process and mechanism of their corresponding HIPEs hydrogels with a temperature-responsiveness. Firstly, Pickering-like globular proteins with an excellent ability to stabilize edHIPEs were screened and obtained, and their structural features (including structural integridity, refolding ability and conformational flexibility) and the corresponding structure-functionality relationships were characterized. Then, the structure-functionship of these Pickering-like globular proteins to stabilize HIPE hydrogels was testified by glycation modification (on non-Pickering-like globular proteins). Lastly, the formation and mechanism of HIPE hydrogels stabilized by Pickering-like globular proteins were investigated, and their temperature-responsiveness and potential applications elucidated. The findings of this project will not only provide a novel strategy for the development of a kind of efficient nano-stabilizers for food-grade HIPEs, and the fabrication of temperature-responsive HIPE hydrogels, but also enrich the knowledge about the emulsification of globular proteins.

诸多球蛋白具有良好的乳化及乳液稳定能力，但迄今国内外对其能否作为一类有效的高内相乳液（HIPEs）稳定剂仍未有定论。申请人新近发现一些天然球蛋白作为一类优越的皮克林纳米稳定剂在稳定HIPEs方面具有广阔的应用前景。本项目拟进一步表征此类皮克林样球蛋白的共性结构特征，揭示其稳定温度响应HIPEs亲水凝胶的实现途径及构效机理。首先，筛选获得具有优越的稳定HIPEs能力的皮克林样球蛋白，表征其结构征（结构完整性、重折叠能力及构象柔顺性），并揭示其构效关系；其次，通过糖苷化修饰手段验证皮克林样球蛋白在稳定HIPEs方面的构效关系；最后，重点研究皮克林样球蛋白稳定HIPEs亲水凝胶的实现途径及机理，并揭示相关HIPEs的温度响应特性及潜在的应用前景。研究成果不仅为研发一类高效的食品级HIPEs纳米稳定剂、创制温度响应HIPEs亲水凝胶提供一条全新的技术途径，而且可丰富对球蛋白的乳化性质的科学认知。

诸多球蛋白具有良好的乳化及乳液稳定能力，但迄今国内外对其能否作为一类有效的高内相乳液（HIPEs）稳定剂仍未有定论。假设球蛋白是一类有效的HIPEs皮克林稳定剂，那么相关的HIPEs又具有哪些特性呢？为了回答上述的疑问，本项目首先探究了能有效稳定HIPEs的球蛋白具有哪些结构特征，以及相关HIPEs亲水凝胶的实现途径及构效关系，并基于此，提出一类性能优越的HIPEs纳米稳定剂的概念。其次，本项目还探究了通常意义上球蛋白作为HIPEs皮克林稳定剂的实现途径及相关分子机制，以期更科学地回答“球蛋白能否作为一类有效的HIPEs稳定剂”这一个悬疑多年的问题。最后，本项目还尝试着探索此类HIPEs（或HIPEs凝胶）作为活性物质包埋载体的潜在应用前景。经过四年的系统研究，达到了预期的研究目标，回答了上述两个科学问题，而且取得了多项较重要的研究进展及发现。重要结果包括：(1) 具有强分子内聚性的球蛋白可充当一类有效的HIPEs纳米稳定剂；(2) 糖苷化修饰是一种有效的使球蛋白转变为HIPEs纳米稳定剂的技术手段，其分子机制在于通过其增强了球蛋白分子内聚性；(3) 除了糖苷化共价修饰之外，添加一定浓度的糖或一定的加热预处理也可使球蛋白的皮克林稳定作用显著增强，其机制与糖分子在蛋白表面形成一层水化层紧密相关；(4) 球蛋白稳定HIPEs具有亲水凝胶的结构特征，而且可作为一类脂溶生物活性物质的抗氧化包埋输送载体。相关研究结果已发表SCI学术论文29篇，其中ESI论文5篇，申请国家发明专利3项（授权2项）。发表的SCI论文已被国内外学者引用1018篇次，其中他引912篇次。相关成果不仅丰富了对球蛋白的乳化稳定机制的认知，而且也为研发一些食品级的HIPEs凝胶制品提供了一种有效的技术解决方案。