Fecha de publicación: 10/01/2025 Fuente: Journal of applied polymer Lugar: RESEARCH ARTICLE This research describes a simultaneous process to obtain cellulose nanocrystals (CNC) and bioactive red onion extract (OPE) from red onion waste. Both biomaterials were used to enhance the properties of polyvinyl alcohol (PVA)-based films. The bio-nanocomposites were fully characterized, and their mechanical and antibacterial activities were investigated. The results highlight that the formulated PVA-CNC(5%)-OPE exhibits effective antibacterial properties, making it appropriate for antibacterial-activated food packaging products.

ABSTRACT
Amidst growing interest in sustainable packaging, this study delves into the preparation of polyvinyl alcohol (PVA)-based biofilms filled with cellulose nanocrystals (CNCs) sourced from red onion skin waste, coupled with bio-active red onion extract (OPE). These innovative bionanocomposite films hold promise for active food packaging applications. The investigation focuses on understanding the interplay between the added agents (OPE and CNC) and the macromolecular chains of PVA. Furthermore, the effects of various OPE concentrations on the physicochemical characteristics and antibacterial properties of CNC-filled PVA bio-nanocomposites were also examined. The integration of CNC and OPE noticeably enhanced the film's properties. Mechanical strength increased by 37%, thermal stability improved with a 92°C increase in decomposition temperature, and UV barrier properties were enhanced by 45%. Additionally, antibacterial activity against foodborne pathogens improved, with the highest inhibition rates reaching 89% against Staphylococcus fungi and 79% against Staphylococcus aureus. The findings demonstrated that the incorporation of bio-active OPE significantly enhanced the UV barrier, antibacterial properties, and biodegradability of PVA-CNC bio-nanocomposite films. These films present a promising approach for sustainable and active food packaging solutions, capable of extending shelf life while reducing environmental impact. Further research in real food systems is recommended to validate these results.