Removal and analysis of foodborne-associated pathogens via peptide functionalized nanoparticles

The use of bacteriophages in food safety and pathogen control. Review

Technological impacts of antibiotic residues in animal-derived fermented foods: Mechanisms, detection challenges, regulatory gaps, and mitigation strategies

Background and Aim: Antibiotic residues (ARs) in foods of animal origin have become a significant concern due to their effects on food safety and food-processing technologies. Although their role in antimicrobial resistance is well recognized, their influence on fermentation processes has received comparatively less attention. This review summarizes current evidence regarding the occurrence of ARs in dairy, meat, and aquatic products and examines their impact on the production of fermented foods. Evidence from different regions indicates that contamination remains widespread, with higher prevalence reported in countries with limited regulatory oversight. Residues of β-lactams, tetracyclines, macrolides, sulfonamides, and fluoroquinolones can inhibit beneficial microorganisms involved in fermentation, including lactic acid bacteria, yeasts, and halophilic microorganisms. Such inhibition disrupts acidification, proteolysis, and flavor development, leading to fermentation failure, reduced product quality, shortened shelf life, and increased risks of pathogen survival and biogenic amine accumulation. The review also compares available detection approaches, including chromatographic, immunological, microbiological, and biosensor-based methods. While advanced analytical techniques offer high sensitivity and specificity, their application remains limited in many low- and middle-income countries due to cost and technical requirements. Furthermore, important differences exist among international regulatory frameworks, creating challenges for monitoring and enforcement. To minimize these risks, a multi-level mitigation strategy involving responsible antibiotic use, improved husbandry practices, enhanced surveillance, rapid screening methods, and technological interventions is discussed. Emerging tools such as biosensors, metagenomics, and artificial intelligence may further strengthen monitoring and control systems. Despite increasing awareness, major research gaps remain, particularly regarding standardized thresholds for fermentation inhibition and the long-term effects of ARs on food microbiomes. Overall, this review highlights that ARs are not only a public health concern but also an important determinant of technological performance in fermented food production. These findings emphasize the need for integrated approaches combining veterinary, microbiological, technological, and regulatory perspectives to ensure food quality and safety. Keywords: Animal-derived foods, antimicrobial resistance, antibiotic residues, biosensors, detection methods, fermented foods, food safety, mitigation strategies.

CONVENTIONAL ISOLATION AND MOLECULAR-LEVEL IDENTIFICATION OF AEROMONAS FROM MEAT SAMPLES: A FOOD SAFETY PERSPECTIVE

Foodborne diseases pose a significant threat to public health, with bacterial contamination of meat being a major concern. Among emerging foodborne pathogens, Aeromonas species have been linked to gastroenteritis, septicemia, and wound infections. This study aimed to isolate and identify Aeromonas species from retail meat samples using conventional cultural and biochemical methods, followed by molecular confirmation through polymerase chain reaction (PCR). A total of 200 meat samples (50 from each type: fish, chicken, mutton, and pork) were collected from various retail markets in Chennai, India. Presumptive Aeromonas isolates were identified using selective plating on Ampicillin Dextrin Agar (ADA), followed by biochemical tests such as oxidase, catalase, Triple Sugar Iron (TSI) test, and citrate utilization. Molecular characterization was performed using species-specific primers targeting 16S rRNA, gyrB, and rpoB genes. The highest prevalence of Aeromonas species was found in pork (62%), followed by mutton (48%), fish (44%) and chicken (36%). PCR analysis confirmed the presence of Aeromonas species and distinguished different strains, validating the accuracy of biochemical identification methods. The study underscores the necessity of integrating conventional and molecular techniques for reliable identification and surveillance of Aeromonas in food sources. Enhanced regulatory measures and routine monitoring of meat products are essential to mitigate the risks associated with Aeromonas contamination and to safeguard public health.  

Impact of food matrix on the activity of a phage-derived thermostable modular lytic enzyme against Salmonella in dairy products.

Food contamination remains a major challenge for the food industry, including the dairy sector. Rich and complex composition of milk provides an excellent environment for the growth of pathogenic microorganisms, among which the most common bacterial contaminants include enterotoxin-producing Staphylococcus aureus, Listeria monocytogenes, Shiga toxin-producing Escherichia coli (STEC), and Salmonella spp. In this study we characterized the modular lytic enzyme MLE-19 obtained through modular engineering and its potential as an antibacterial agent to protect milk and dairy products against Salmonella enterica ssp. enterica PCM 2266. We demonstrated that MLE-19 with a catalytic domain of the thermostable endolysin Ph2119, exhibited high thermal stability with a Tm of 101.66°C. Furthermore, pre-treatment of MLE-19 under pasteurization conditions (80°C, 10 min) enhanced its anti-Salmonella activity compared with the unheated enzyme (reductions of 1.14 and 0.45 log units compared with the control), highlighting its applicability in the dairy industry. The minimum inhibitory concentration (MIC) of MLE-19 against Salmonella cells was 100 µg/mL, and the presence of 0.5 mM EDTA reduced this value 4-fold (to 25 µg/mL). MLE-19 caused significant decreases in bacterial load at concentrations of 12.5 and 200 µg/mL for planktonic and biofilm cells, respectively. Food matrix represented by milk, yogurt and cottage cheese and external conditions such as temperature and duration had a variable impact on the protective activity of MLE-19. Significant reductions were observed in all food matrices with the most pronounced antibacterial effects in milk, where up to 3 log reduction when storing at 4°C and 20°C were achieved. We propose that the enzyme exhibited greater mobility in milk, enabling more efficient access to and degradation of Salmonella cells. Our findings identify the thermostable MLE-19 as a new promising agent for controlling Salmonella spp. in the dairy industry.

Detection of foodborne pathogens in ready-to-serve food samples in Malaysian public universities

Foodborne illnesses remain a significant public health concern, particularly in institutional settings such as public universities, where large populations are served daily. This study investigates the detection of foodborne pathogens, including Salmonella, Listeria, Escherichia coli O157:H7, as well as Vibrio cholerae in ready-to-serve food samples collected from university cafeterias, food courts, and residence halls. A total of 127 food samples were obtained from multiple campuses and subjected to microbiological analysis using standard enrichment and PCR assay. The findings revealed that three types of pathogens, for example, V. cholerae, E. coli O157 and E. coli O157:H7, were detected. Overall, the results underscore the potential health hazards linked to improper food handling as well as storage practices in university food services. Moreover, the study highlights the need for stricter hygiene protocols, regular microbial surveillance, and staff training to mitigate contamination risks.

Antimicrobial Efficacy and Transcriptomic Mode of Action of GS-2 Against Foodborne Pathogens

The transition toward reusable food packaging driven by European circular economy regulations introduces new food safety challenges related to microbial persistence and cross-contamination. GS-2 is a novel, food-safe antimicrobial formulation developed for use as a coating on reusable packaging materials. In the present study, the intrinsic antimicrobial activity of GS-2 was evaluated in liquid suspension against foodborne bacterial (Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella enterica Agona) and fungal pathogens (Aspergillus flavus and Aspergillus niger), and the transcriptomic response of L. monocytogenes following sublethal GS-2 exposure was investigated. GS-2 exhibited concentration-dependent microbicidal activity, with strong reductions observed at ≥2.8–3.0% against bacterial strains and A. flavus, while A. niger demonstrated resistance. Among bacteria, L. monocytogenes showed the greatest sensitivity, with populations reduced below detection limits at 3% GS-2. To elucidate mechanistic responses, RNA sequencing was performed on L. monocytogenes exposed to sublethal GS-2 concentrations (0.1–1.0%). Transcriptomic analyses using discrete and continuous models revealed a pronounced adaptive stress response at 0.5% GS-2, characterized by coordinated upregulation of pathways involved in carbon, nitrogen, and nucleotide metabolism. At higher sublethal concentrations (1%), transcriptional profiles shifted toward growth arrest and cellular damage management. These findings support GS-2 as a promising antimicrobial for enhancing the microbial safety of reusable food packaging systems.