Title
Formation and characterization of supramolecular structures of β-lactoglobulin and lactoferrin proteins
Author
Camila Santiago Saraiva, Jane Séliados Reis Coimbra, Alvaro Vianna Novaesde Carvalho Teixeira, Eduardo Basíliode Oliveira, Reinaldo Francisco Teófílo, Angélica Ribeiroda Costa, Évertonde Almeida Alves Barbosa
Year
2017
Journal
Food Research International
Abstract
Combination of β-lactoglobulin (β-Lg) and lactoferrin (Lf), biomacromolecules derived from bovine whey, was used in the formation of supramolecular structures by thermal gelation technique to adjust the pH. Furthermore, the influence of the molar ratio, temperature, pH, and heating time in the formation of supramolecular structures were also studied. The characterization of the protein supramolecular structures was performed using dynamic light scattering, zeta potential measurements, molecular spectrofluorimetry, and circular dichroism spectroscopy. The thermal behavior of the pure proteins was investigated by differential scanning calorimetry. The protein denaturation temperatures were of around 85 °C for the β-Lg and around 52 °C and 85 °C (a small portion) for the Lf. The protein molar ratio of 2:1 Lf/β-Lg was used to form the structures, whose characterization showed that the best conditions of supramolecular structure formation occurred at pH 6.5 and at temperatures of 62.5 °C. In those conditions, more stable systems with reduced hydrophobic surface and average sizes between 30 and 100 nm were generated. The correlation between pH and temperature suggests that the method of preparation of the supramolecular structure affects its size during storage.
Instrument
J-810
Keywords
Circular dichroism, Secondary structure, Thermal stability, Protein folding, Chemical stability, Food science, Biochemistry