Portal de Periódicos da CAPES

Artigo Produção Nacional Revisado por pares

BIBTEX RIS

β-lactoglobulin conformation influences its interaction with caffeine

2021; Elsevier BV; Volume: 44; Linguagem: Inglês

10.1016/j.fbio.2021.101418

2212-4306

Lívia Neves Santa Rosa, Jaqueline de Paula Rezende, Yara Luíza Coelho, Tiago Antônio Oliveira Mendes, Luís Henrique Mendes da Silva, Ana Clarissa dos Santos Pires,

Microencapsulation and Drying Processes

Caffeine is a molecule with bioactive properties related to increased mental performance. Its use in food products is limited by its bitterness and self-association behavior. The complex formed by β-lactoglobulin and caffeine was characterized by fluorescence spectroscopy, isothermal titration calorimetry, and molecular docking. Fluorescence spectroscopy revealed that β-lactoglobulin interacted with caffeine to form a 1:1 stoichiometric complex. Isothermal titration calorimetry characterization of β-lactoglobulin-caffeine binding revealed a different stoichiometry (1:3). Molecular docking analysis confirmed the information obtained by the two thermodynamic evaluation techniques, showing that the best interaction occurred in the hydrophobic cavity of β-lactoglobulin. The effect of protein conformation was also evaluated by fluorescence spectroscopy. The complex stoichiometry and binding constants were from the same order as those obtained for native β-lactoglobulin. However, in contrast to the complex formation with native protein, the flexibility increase observed in the thermal unfolded protein promoted a great temperature effect on the standard enthalpy and entropy changes of interaction, indicating the presence of a balance between hydrophobic and hydrophilic forces.