Development and Characterization of a Functional Smart PVA/NC/PCL Nano-biocomposite Using E. Coli Phage: Insights into Physicochemical Properties and Antimicrobial Activity

Food packaging plays a critical role in preserving the freshness and quality of foods while preventing microbial spoilage. Advances in this field have led to the development of intelligent and active packaging systems incorporating nanotechnology. Among these, electrospinning has gained attention for producing nanofibrous materials with high surface-to-volume ratios, enabling the efficient loading of active agents.In response to the growing concern over antibiotic-resistant bacteria, this study investigates the use of bacteriophages as an alternative antimicrobial agent. Lytic bacteriophages targeting Escherichia coli were isolated from Caspian seawater and immobilized onto electrospun nanofibers composed of polyvinyl alcohol (PVA), polycaprolactone (PCL), and bacterial nanocellulose (BNC). SEM confirmed successful phage immobilization, while TEM revealed their classification within the Siphoviridae and Podoviridae families.The addition of PCL to PVA enhanced the fibers' mechanical strength, reduced defects, and improved water resistance. Incorporating BNC further strengthened the nanofiber structure and enhanced its matrix properties. Antimicrobial testing using the disc diffusion method revealed an inhibition halo of 13 mm, exceeding that of the antibiotic ampicillin. Notably, the functionalized nanofibers retained antimicrobial efficacy for up to one month, with stable phage viability at 24°C, 4°C, and -20°C.These findings demonstrate the potential of electrospun nanofibers functionalized with bacteriophages as a sustainable solution for combating bacterial contamination in food packaging, contributing to enhanced food safety and extended shelf life.