Enhancement of mannosylerythritol lipid-A on physicochemical stability, antioxidant activity, and bioavailability of bovine lactoferrin emulsion under different pH conditions

This study systematically explored the enhancement of mannosylerythritol lipid-A (MEL-A) on physicochemical stability, antioxidant activity, and bioavailability of bovine lactoferrin (BLF) emulsion under different pH conditions by spectroscopic techniques, molecular simulation, and simulated in vitro digestion model. The bovine lactoferrin-MEL-A (BLF-MEL-A) emulsions were prepared and characterized with the Fourier infrared, of which results showed that high concentration MEL-A (1.00 mg/mL) changed the secondary structure of pH-induced BLF and rendered an increase in β-sheet and random coil fractions. Based on the results of fluorescence spectrum and isothermal titration calorimetry, hydrogen bonding, van der Waals forces, and electrostatic force were the interaction forces of BLF and MEL-A, which were similar to the simulated data of molecular docking and molecular dynamics. BLF-MEL-A emulsion also exerted considerable antioxidant activities and had great potential for functional food development. In addition, MEL-A could improve the stability of BLF emulsion in simulated in vitro digestion test, which promoted the bioavailability of BLF. Therefore, this study will facilitate to explore the interaction between BLF and MEL-A and expand the application of MEL-A as a food additive in food industry.