Synergistic effects of Lantana camara leaf extract and in-situ AgNPs in chitosan/PVA films for lamb meat preservation

This study explores sustainable, eco-responsive food packaging using chitosan (CS) and polyvinyl alcohol (PVA) films incorporated with Lantana camara leaf extract (LCE) and in-situ synthesized silver nanoparticles (AgNPs). Methanolic extraction of Lantana camara yielded a phenolic content of 165 ± 0.62 mg GAE/g. AgNPs formation was confirmed by a color change (yellowish to dark brown), and UV absorbance at 431 nm, further supported by XRD and SEM analyses. Incorporating AgNPs with LCE enhanced UV–vis light blocking, reducing transparency from 24 % (control) to 14 % (CPLS), and improved hydrophobicity, with a 25 % increase in water contact angle. Tensile strength ranged from 41.052 ± 2.209 MPa (control) to 45.789 ± 2.653 MPa (CPL-3). The water vapor transmission rate (WVTR) decreased by 35 % (0.052 ± 0.03 g/m². day), confirming superior barrier properties, supported by water solubility and moisture retention data. Biodegradation tests showed pristine CS/PVA lost 50 % mass in 50 days, while CPLS (with AgNPs) lost only 10 % in the same period. Migration limits of CP/CPLS films were within the permissible 10 mg/dm² for aqueous, acidic, and alcoholic food simulants. The films exhibited strong antioxidant activity, with 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging rates of 88 % (CPL-3) and 92 % (CPLS), and inhibited food-borne pathogens, showing zones of inhibition of 12.0 ± 0.9 mm ( E. coli ) and 12.8 ± 0.5 mm ( S. aureus ). Remarkably, CPLS extended lamb meat shelf life to 15 days at 4°C, as evidenced by reduced total psychrotrophic bacteria count (TPBC) and lipid peroxidation. These nanocomposite films meet essential criteria for sustainable meat packaging, offering a green alternative with enhanced functional properties. • Multifunctional nanocomposite films were fabricated using the solvent casting method. • LCE and in-situ AgNPs enhanced mechanical, UV-blocking, and barrier properties. • CPL-3 and CPLS films exhibited excellent antioxidant and antimicrobial activities. • All films exhibited biodegradability in soil, confirming eco-friendliness. • The shelf life of lamb meat was extended to 15 days at 4 °C using CPLS films.