Formation of tannic acid-binding ovalbumin amyloid fibril hydrogels: Enhanced antibacterial and antioxidant properties

The protein-induced amyloid fibrils (AFs) are limited in food industry due to their poor antioxidant and antibacterial activities. However, polyphenol shows the potential functional modifications of AFs, and extend their application in food processing. In present study, tannic acid-binding ovalbumin-induced AFs (TA-OAFs) hydrogels were fabricated via different concentrations of TA and ovalbumin amyloid fibrils, and the rheological properties, thermal stability, and morphology of the hydrogels were investigated. Then, the physiochemical, antioxidant, and antibacterial of TA-OAFs hydrogels were further analyzed. The obtained results indicated that the addition of TA could increase the average diameter of nanofibrils with increased β-sheet contents, and showed a TA concentration-dependent tendency. Moreover, TA-OAFs hydrogels also possessed better thermal stability, antioxidant activity, and antibacterial capacity for both Gram-negative and Gram-positive bacteria. The present study might contribute to a better understanding of antimicrobial materials designing of protein-induced amyloid fibrils in the food field with beneficial properties.