Preparation of capsicum leaf protein/lignocellulose nanocrystals/corn starch composite antibacterial packaging films by in-situ green-synthesized silver oxide nanoparticle.

Abstract

The traditional chemical reduction method for preparing metal nanoparticles requires organic solvents, which seriously affects the ecological environment. Meanwhile, polysaccharide-based packaging films' brittleness limits their application scope. In contrast, protein-based packaging films (PBPFs) have excellent flexibility and ductility. Therefore, this study synthesized novel PBPFs loaded with silver oxide nanoparticles (Ag2O NPs) in situ and green by microwave technology. The results showed that the Ag2O NPs reduced up to 90.03 % in the reduction system of this study. With increased silver nitrate concentration, Ag2O NP reduction rates and the degree of intermolecular interaction of the film-forming fluids decreased, and PBPF crystallinity and thermal stability increased. PBPFs exhibit increased interfacial interaction when Ag2O NPs generated by reduction are uniformly distributed on their surfaces. The maximum tensile strength of PBPFs was 8.87 ± 0.71 MPa, and the maximum WCA was 97.58 ± 4.05°. All PBPFs have UV-blocking properties and antimicrobial activity, extending grape storage life.