UTTAR PRADESH JOURNAL OF ZOOLOGY

Biofilm-forming foodborne bacteria in meat products represent an important food-safety concern because biofilms promote bacterial persistence, cross-contamination, and tolerance to conventional antimicrobial agents and sanitisers. This study aimed to isolate bacteriocin-producing lactic acid bacteria (LAB) from dairy products and evaluate their inhibitory activity against biofilm-producing bacterial isolates recovered from meat samples. Eight milk and milk-product samples were screened, yielding 20 LAB isolates comprising Lactobacillus (50%), Lactococcus (35%), Enterococcus (10%), and Leuconostoc (5%). A total of 30 bacterial isolates were recovered from chicken, goat meat, and fish samples, including Escherichia coli, Staphylococcus aureus, Enterococcus faecalis, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus mirabilis, and Salmonella spp. Biofilm formation was assessed using Congo Red Agar and 15 isolates (50%) were biofilm positive. E. coli showed the highest biofilm-forming frequency (80%), followed by Salmonella spp. (66.7%) and S. aureus (60%). Cell-free supernatants of LAB cultures were used as crude bacteriocin preparations and exhibited variable antibacterial activity against the biofilm-producing meat isolates, with inhibition zones ranging from 12 to 25 mm. LAB isolate 6 exhibited the broadest inhibitory activity, showing measurable inhibition against all seven tested pathogens. The selected isolate was identified by biochemical characterization and 16S rRNA gene sequencing as Lactobacillus plantarum (99.28% sequence identity). These findings indicate that milk-derived bacteriocin-producing LAB, particularly L. plantarum, may serve as a natural and cost-effective biocontrol agent.