Protein-derived antibacterial antioxidant nanoenzyme for fruit preservation

As monofunctional packaging becomes less able to satisfy the need for environmentally friendly convenience, functionalized packaging is becoming more and more significant in food applications. In this study, a biomimetic artificial nano-enzyme, bovine serum albumin (BSA) chelated with copper ions (CuBSA), was constructed by imitating the structure of natural superoxide dismutase (SOD). This novel CuBSA metallo-nanoenzyme possesses distinct SOD-like enzyme activity, antibacterial capabilities, as well as thermal stability and biocompatibility. With CuBSA as excellent filler, the carrageenan-based nanocomposite films were obtained, showing excellent performance in retarding enzymatic browning and inhibiting microbial attack on fresh-cut apples and figs, even stored at room temperature. More importantly, this new composite film is low-cost and simple to be synthesized for large-scale use.