Self-assembled α-lactalbumin nanostructures: encapsulation and controlled release of bioactive molecules in gastrointestinal in vitro model

BACKGROUND: Implementing encapsulation techniques is pivotal in safeguarding bioactive molecules against environmental conditions for drug delivery systems. Moreover, the food-grade nanocarrier is a delivery system and food ingredient crucial in creating nutraceutical foods. Nano alpha-lactalbumin has been shown to be a promissory nanocarrier for hydrophobic molecules. Furthermore, the nanoprotein can enhance the tecno-functional properties of food such as foam and emulsion. The present study investigated the nanostructured alpha-lactalbumin protein (nano alpha-la) as a delivery and controlled release system for bioactive molecules in a gastric-intestinal in vitro mimic system. RESULTS: The nano alpha-la was synthesized by a low self-assembly technique, changing the solution ionic strength by NaCl and obtaining nano alpha-la 191.10 +/- 21.33 nm and a spherical shape. The nano alpha-la showed higher encapsulation efficiency and loading capacity for quercetin than riboflavin, a potential carrier for hydrophobic compounds. Thermal analysis of nano alpha-la resulted in a Delta H of -1480 J g(-1) for denaturation at 57.44 degrees C. The nanostructure formed by self-assembly modifies the foam volume increment and stability. Also, differences between nano and native proteins in emulsion activity and stability were noticed. The release profile in vitro showed that the nano alpha-la could not hold the molecules in gastric fluid. The Weibull and Korsmeyer-Peppas model better fits the release profile behavior in the studied fluids. CONCLUSION: The present study shows the possibility of nano alpha-la as an alternative to molecule delivery systems and nutraceutical foods' formulation because of the high capacity to encapsulate hydrophobic molecules and the improvement of techno-functional properties. However, the nanocarrier is not perfectly suitable for the sustainable delivery of molecules in the gastrointestinal fluid, demanding improvements in the nanocarrier. (c) 2024 Society of Chemical Industry.