Plant-mediated synthesis of zinc oxide nanoparticles and their applications in biopolymer-based sustainable food packaging: A state of-art-review

The physical and chemical synthesis methods of zinc oxide nanoparticles (ZnONPs) often require high energy or involve toxic reagents producing hazardous byproducts. Plant-mediated synthesis of ZnONPs, in retrospect, is a sustainable synthetic approach with significant potential for novel applications. Bioactive compounds of plant extracts act as reducing and stabilizing agents, offering an eco-friendly alternative to the conventional chemical and physical synthesis techniques. Plant-mediated ZnONPs exhibit comparable functional properties, including potential antimicrobial properties, exceptional UV-light barrier capabilities, and controlled release kinetics, making them ideal for enhancing the performance of biopolymer-based food packaging films. This review highlights synthesis of plant-mediated ZnONPs for application in biopolymeric packaging materials i.e., films and coatings, and their effects on the mechanical, thermal, antimicrobial, and other functional properties of the biopolymer matrix. Moreover, applications of ZnONPs incorporated biopolymer-based active films and coatings in packaging and shelf-life extension of perishable foods like fruits and vegetables, muscle foods, dairy products, etc. are also elaborated. Biopolymer-based nanocomposite films have demonstrated efficacy in preserving the freshness and quality of perishable food products including fresh fruits, vegetables, muscle foods, and dairy items by inhibiting microbial growth and extending shelf-life. Additionally, their ability to serve as high-tensile, biodegradable packaging materials aligns with the global push toward reduction of synthetic plastics usage. The integration of plant-mediated ZnONPs offers a sustainable solution for food packaging and preservation challenges while minimizing environmental impact. • Plant-mediated synthesis of ZnO nanoparticles (ZnONPs) is a sustainable synthetic approach. • This review highlights applications of biogenic ZnONPs in sustainable food packaging. • Nanocomposite films preserve the freshness and quality of perishable foods. • Integration of biogenic ZnONPs with biopolymer improves tensile strength and UV-barrier.