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Article Biocontrol of Listeria Monocytogenes in Milk: Isolation and Characterization of a Novel Bacteriophage Cocktail(Elsevier Sci Ltd, 2026) Unal, Gultekin; Cufaoglu, Gizem; Cengiz, Gorkem; Acar, Bahar Onaran; Ayaz, Naim Deniz; Erdinc, Ayse Nur; Vural, Ilgin AtaListeria monocytogenes is a significant foodborne pathogen known for its persistence in food processing environments and resistance to various stress conditions. This study aimed to isolate and characterize bacteriophages specific to L. monocytogenes and evaluate their potential as biocontrol agents in milk. A total of 43 phages were isolated from diverse wastewater sources across Türkiye. Based on their host range, lytic activity, and growth kinetics, two phages (LM1116TR and LM1418TR) were selected for further comprehensive phenotypic and genomic characterization. Host range assays revealed high specificity toward L. monocytogenes, with lytic activity observed against multiple serotypes (1/2a, 1/2b, 1/2c, and 4b). Transmission electron microscopy revealed that the phages exhibit a myovirus-like morphotype and belong to the class Caudoviricetes. Whole-genome sequencing confirmed that two phages had complete circular genomes lacking antimicrobial resistance genes. Thermal stability tests showed the phages remained detectable after 1 h at 40 degrees C, 50 degrees C, and 60 degrees C but were sensitive to acidic pH, especially to pH 3. Significant reductions in L. monocytogenes counts were observed following phage cocktail treatment, reaching up to 4.22 log CFU/mL in vitro (37 degrees C) and 1.66 log CFU/mL in UHT milk (4 degrees C) (p < 0.001). Additionally, one-year storage tests at +4 degrees C, -20 degrees C, and -80 degrees C in tryptic soy broth (TSB), SM buffer, physiological saline and Tris-Buffered Saline (TBS, 1 & times; ) identified TSB with 20% glycerol as the most suitable for preserving phage stability at subzero temperatures. These results show the potential of new phages as effective and stable biocontrol agents against L. monocytogenes in food safety applications, supporting their potential as biocontrol agents, particularly within the dairy industry.Article Novel Enterococcus Phages Identified through Comprehensive Screening to Control Contamination in Chicken Meat(Wiley, 2026) Unal, Gultekin; Cengiz, Gorkem; Cufaoglu, Gizem; Acar, Bahar Onaran; Ayaz, Naim Deniz; Yildiz, Tansu; Erdinc, Ayse NurBACKGROUND Antibiotic-resistant Enterococcus faecalis and E. faecium are persistent contaminants in food and environmental settings, including poultry-related matrices, contributing to food safety risks and antimicrobial resistance (AMR) dissemination. This study aimed to identify Enterococcus phages through environmental screening and evaluate their biocontrol potential using a chicken wing food model. RESULTS From 1719 environmental samples, 45 Enterococcus-targeting phages were isolated, and two (Efs.1 1-1 and Efm 3-10) with the broadest lytic profiles were selected for characterization. Transmission electron microscopy revealed that both phages belong to Caudoviricetes with siphovirus-like morphology, latent periods (6-8 min), and high burst sizes (90-110 PFU per cell). Whole-genome sequencing revealed complete circular genomes with estimated completeness values between 0.97 and 1.00, and no detectable virulence, lysogeny, or AMR genes. The phages were stable at pH 4 for 60 min and tolerated 40-60 degrees C for 1 h. Phage titers decreased from 10.0 to no less than 6.0 log PFU mL(-1) across all storage conditions over 12 months. In vitro assays in tryptic soy broth showed that while the control groups reached 8.56-9.12 log CFU mL(-1) at 24 h at 37 degrees C, no bacteria were detected in any of the phage-treated samples (limit of detection: 1 CFU mL(-1)). In the chicken wing food model, phage treatment maintained bacterial counts below the detection limit (<1 log CFU g(-1)) throughout refrigerated storage. Mean log reductions reached 1.78-2.78 and 3.71-4.71 log CFU g(-1), respectively. CONCLUSION These novel lytic phages exhibit strong stability and rapid antibacterial activity, offering promising biocontrol agents to reduce Enterococcus contamination in chicken meat.
