Microbial contamination of foods is one of the major public health challenges worldwide, and the development of bioactive packaging systems capable of inhibiting microbial growth has attracted considerable attention. This study aimed to evaluate the antimicrobial activity of gelatin–carboxymethyl cellulose films incorporated with silver nanoparticles and Echinophora sibthorpiana essential oil against selected foodborne pathogenic bacteria.
The essential oil was extracted by hydrodistillation using a clevenger apparatus, and its chemical composition was characterized by gas chromatography–mass spectrometry (GC–MS). Silver nanoparticles were synthesized through a green synthesis approach. gelatin–carboxymethyl cellulose films containing silver nanoparticles (0.015%) and Echinophora sibthorpiana essential oil at concentrations of 0.3% and 0.6% were prepared using the solvent-casting method. Antimicrobial activity was evaluated against Staphylococcus aureus, Listeria monocytogenes, Escherichia coli, and Salmonella Typhimurium using the disk diffusion assay.
The major constituents of the essential oil were Ocimene (26.98%), 2,3-Dimethyl-cyclohexa-1,3-diene (8.48%), and α-Pinene (7.99%). The gelatin–carboxymethyl cellulose film without active additives exhibited no antimicrobial activity. However, incorporation of silver nanoparticles significantly enhanced the antimicrobial properties of the films. Furthermore, increasing the concentration of Echinophora sibthorpiana essential oil from 0.3% to 0.6% resulted in a significant increase in the inhibition zone diameter against all tested microorganisms. The strongest antimicrobial activity was observed for films containing silver nanoparticles and 0.6% essential oil.
The results demonstrated that silver nanoparticles and Echinophora sibthorpiana essential oil enhanced the antimicrobial activity of gelatin–carboxymethyl cellulose films. These bioactive films could serve as a promising alternative for active food packaging applications and for improving antimicrobial properties.