食品中多酚与二氧化钛纳米颗粒的相互作用及其对多酚生物利用度和生物活性的影响

随着食品工业的快速发展，多酚和二氧化钛在食品体系中的共存日益频繁。研究表明多酚可与食品添加剂二氧化钛纳米颗粒发生电荷转移相互作用，但决定该相互作用的关键多酚结构和二氧化钛特性及该相互作用对多酚生物利用度和生物活性的影响及原因尚不明确。因此，本项目拟选不同结构的多酚和不同特性的二氧化钛纳米颗粒，采用红外、拉曼和分子模拟等技术研究多酚与二氧化钛的作用位点、强度等信息，揭示决定多酚和二氧化钛电荷转移相互作用的关键多酚结构和二氧化钛特性，为食品中多酚和二氧化钛相互作用的深入研究提供理论基础。建立胃肠道消化模型，探究该相互作用对多酚生物利用度的影响，采用体外化学和细胞模型等手段测定该相互作用对多酚抗氧化活性及对2-型糖尿病关键酶的抑制活性的影响，结合多酚和二氧化钛相互作用的研究结果分析该相互作用对多酚生物利用度和生物活性影响的原因，为研究复杂食品体系中多酚的功能变化、指导人们合理膳食提供科学依据。

With the rapid development of the food industry, polyphenols and titanium dioxide (TiO2) coexist more and more frequently in the food system. TiO2 nanoparticles as food additives can interact with polyphenols via charge transfer interaction. However, the key structures of polyphenols and the key properties of TiO2 that determine this interaction as well as the cause and effects of this interaction on the bioavailability and bioactivities of polyphenols are not yet clear. Therefore, this project will study the interaction site and strength between polyphenols with different structures and TiO2 nanoparticles with different characteristics by FTIR, Raman spectroscopies and molecular simulation techniques in order to analyze the key polyphenols structures and TiO2 properties that determine the charge transfer interaction. This part of research can provide the theoretical basis for further research on the interaction between polyphenols and TiO2 in foods. The effect of this interaction on the bioavailability of polyphenols will be explored by establishing an in vitro digestive model. The in vitro chemical and cellular models will be used to determine the effects of this interaction on the antioxidant activity and inhibitory activities of polyphenols against key enzymes relevant for type 2 diabetes. The cause of effects of this interaction on the bioavailability and bioactivity of polyphenols will be analyzed based on the results of the interactions between polyphenols and TiO2. These studies will provide a scientific basis for the functional changes of polyphenols in complex food systems as well as provide people with proper guidance on nutritious meal.