Nunes Natália Moreira, Pacheco Ana Flávia Coelho, Agudelo Álvaro Javier Patiño, da Silva Luis Henrique Mendes, Pinto Maximiliano Soares, Hespanhol Maria do Carmo, Pires Ana Clarissa Dos Santos
Grupo de Termodinâmica Molecular Aplicada, Departamento de Tecnologia de Alimentos, Av, PH Rolfs, s/n, Campus Universitário, Viçosa, MG 36570-000, Brazil.
Grupo de Química Verde Coloidal e Macromolecular, Departamento de Química, Universidade Federal de Viçosa, Av, PH Rolfs, s/n, Campus Universitário, Viçosa, MG 36570-000, Brazil.
Food Chem. 2017 Dec 15;237:525-531. doi: 10.1016/j.foodchem.2017.05.131. Epub 2017 May 26.
Cinnamic acid (CA) and methyl cinnamate (MC) have attracted interest of researchers because of their broad therapeutic functions. Here, we investigated the interaction of CA and MC with bovine serum albumin (BSA) at pH 3.5, 5.0, and 7.4 using fluorescence spectroscopy, differential scanning nanocalorimetry, and measurements of interfacial tension, size, and zeta potential. BSA formed a complex with the ligands with stoichiometry of approximately 1.0. At pH 7.4, CA-BSA complex formation was entropically driven. The interaction between MC and BSA was more favorable than with CA and was enthalpically driven under the same conditions. The pH played an important role in BSA conformation, which altered the manner in which it interacts with the ligands. Interestingly, both CA and MC had no effect on the surface tension of BSA/air interfaces. These data contribute to the knowledge of CA/MC-BSA interactions and provide important data for application in the food industry.
肉桂酸（CA）和肉桂酸甲酯（MC）因其广泛的治疗功能而引起了研究人员的兴趣。在此，我们使用荧光光谱法、差示扫描纳米量热法以及界面张力、尺寸和zeta电位测量，研究了在pH值为3.5、5.0和7.4时CA和MC与牛血清白蛋白（BSA）的相互作用。BSA与配体形成了化学计量比约为1.0的复合物。在pH 7.4时，CA-BSA复合物的形成是由熵驱动的。在相同条件下，MC与BSA之间的相互作用比与CA的相互作用更有利，且是由焓驱动的。pH值在BSA构象中起着重要作用，这改变了它与配体相互作用的方式。有趣的是，CA和MC对BSA/空气界面的表面张力均无影响。这些数据有助于了解CA/MC-BSA相互作用，并为食品工业中的应用提供重要数据。
