Mantovani Raphaela Araujo, Hamon Pascaline, Rousseau Florence, Tavares Guilherme M, Mercadante Adriana Zerlotti, Croguennec Thomas, Bouhallab Saïd
Department of Food Science, Faculty of Food Engineering, University of Campinas, Campinas, São Paulo 13083-862, Brazil.
INRAE, Institut Agro, STLO, F-35042 Rennes, France.
Food Res Int. 2020 Dec;138(Pt B):109781. doi: 10.1016/j.foodres.2020.109781. Epub 2020 Oct 15.
Understanding the food protein binding to bioactive compounds is of utmost importance for the development of efficient protein-based delivery systems. The binding of lutein to sodium caseinate (NaCas) or native casein micelle (PPCN) was investigated at pH 7 to evaluate the effect of casein supramolecular structures on the interaction. Fluorescence quenching, UV-vis spectroscopy, and dynamic light scattering were carried out. Under the medium conditions of interaction analysis (DMSO-water and ethanol-water), lutein exists as H-type aggregates. The investigation of lutein/casein interaction showed a predominantly static mechanism of fluorescence quenching and the presence of two fluorophore populations on NaCas and PPCN, but only one accessible to lutein. Moreover, the Scatchard plot indicated that lutein interacted with both caseins in one binding site. The interaction of lutein with caseins occurred with binding constant K of 10 M, regardless of casein supramolecular structure.
了解食物蛋白质与生物活性化合物的结合对于开发高效的基于蛋白质的递送系统至关重要。在pH 7条件下研究了叶黄素与酪蛋白酸钠（NaCas）或天然酪蛋白胶束（PPCN）的结合，以评估酪蛋白超分子结构对相互作用的影响。进行了荧光猝灭、紫外可见光谱和动态光散射实验。在相互作用分析的介质条件下（二甲基亚砜-水和乙醇-水），叶黄素以H型聚集体形式存在。叶黄素/酪蛋白相互作用的研究表明，荧光猝灭主要是静态机制，并且在NaCas和PPCN上存在两个荧光团群体，但叶黄素只能接触到其中一个。此外，Scatchard图表明叶黄素在一个结合位点与两种酪蛋白相互作用。无论酪蛋白超分子结构如何，叶黄素与酪蛋白的相互作用的结合常数K均为10 M。
