It is essential to understand the ultrasound-induced changes in assembly of proteins and polyphenols into non covalent nanocomplex. β-Lactoglobulin (LG) and chlorogenic acid (CA) with various biological activities can be combined to form food-grade nanocomplexes. This study systematically explored the role of high-intensity ultrasound pretreatment on the binding mechanisms of LG and CA, and the potential biological function for embedding curcumin (Cur). The scanning electron microscopy (SEM) revealed that ultrasound treatment could destroy the structure of LG, and the particle size of the protein was reduced to<50 nm. The change in secondary structure of the protein by ultrasound treatment could be revealed by the fourier transform infrared (FTIR) and fluorescence spectra. Besides, it was found that LG and CA were combined to form a complex under the hydrophobic interaction, and CA was bound in the internal cavity of LG with a relatively extended conformation. The result demonstrated that the ratio of Cur embedded in the ultrasonic sample could be effectively increased by 7% − 10%, the particle size in the emulsion was smaller, and the dispersion was more stable. This work contributes to the development of protein–polyphenol functional emulsion systems with the ability to deliver Cur.

必须了解超声诱导的蛋白质和多酚组装成非共价纳米复合物的变化。具有多种生物活性的β-乳球蛋白（LG）和绿原酸（CA）可以结合形成食品级纳米复合物。本研究系统探讨了高强度超声预处理对 LG 和 CA 结合机制的作用，以及包埋姜黄素 (Cur) 的潜在生物学功能。扫描电子显微镜（SEM）显示，超声处理可以破坏LG的结构，蛋白质的粒径减小到<50 nm。通过傅里叶变换红外 (FTIR) 和荧光光谱可以揭示超声处理后蛋白质二级结构的变化。除了，发现LG和CA在疏水作用下结合形成复合物，CA以相对延伸的构象结合在LG的内腔中。结果表明，Cur嵌入超声样品中的比例可有效提高7%~10%，乳液中粒径更小，分散更稳定。这项工作有助于开发具有传递 Cur 能力的蛋白质-多酚功能乳液系统。