Molecular interactions involved in the complexation process between buffalo whey proteins concentrate and folic acid

Using buffalo whey proteins as carrier agents of sensitive molecules raises an interesting approach allowing adding value and minimizing the pollution impact of this by-product. In this context, this work aims to explore the molecular interactions between buffalo whey proteins concentrate (BWPC) and folic acid (FA). For this purpose, fluorescence, UV and FTIR analysis were performed on aqueous or solid dispersions of a buffalo whey protein concentrate (5 μM) (BWPC), with variable concentrations (0-20 μM) of FA. Fluorescence and absorption data were fitted by Stern-Volmer, Beckett, Förster resonance energy transfer, and sphere-of-action models (R² > 0.9). Derived results suggest that BWPC strongly bind to FA through non-covalent interactions and form ground-state complexes. Additionally, BWPC improves the photostability of FA against UV radiation, and chemical denaturation negatively affects the binding properties. Obtained results encourage further studies of BWPC as carrier agents, which could promote innovative applications for this under-utilized proteins source.