Co-assembled whey protein and proanthocyanidins as a promising biocarrier for hydrophobic pterostilbene: Fabrication, characterization, and cellular antioxidant potential
Weigang Zhong, Qi Wang, Min Li, Xuming Deng, Xue Shen
Abstract
The usage of food-derived polyphenols with different polarities has been limited by their instability and incompatibility. Therefore, a biocarrier was developed by co-assembly of whey protein isolate (WPI) and hydrophilic proanthocyanidin (PC) for loading hydrophobic pterostilbene (PTE). Such biocarrier has superior affinity for PTE than WPI alone as determined by encapsulation efficiency (EE) and loading capacity (LC) assay, fluorescence quenching analysis and molecular docking, while assembly process was characterized by particle size and zeta-potential, 3D fluorescence and SEM. CD and FTIR spectra confirmed the α-helix to β-sheet and random coil transition of proteins during the nanocomplexes formation. WPI acted as a mediator through altering the binding mode of PC and PTE, allowing them to perform significant synergistic effects in enhancing ABTS and DPPH radical scavenging and reducing H 2 O 2 -induced cell damage. This research may serve to develop new protein/polyphenol co-loading systems and offer a reliable nutritional fortification.