Fresh vegetables are an essential part of a healthy diet, but microbial contamination of fruits and vegetables is a serious concern to human health, not only for the presence of foodborne pathogens but because they can be a vehicle for the transmission of antibiotic-resistant bacteria. This work aimed to investigate the importance of fresh produce in the transmission of extended-spectrum β-lactamases (ESBL)-producing Enterobacteriaceae. A total of 174 samples of vegetables (117) and farm environment (57) were analysed to determine enterobacterial contamination and presence of ESBL-producing Enterobacteriaceae. Enterobacterial counts above the detection limit were found in 82.9% vegetable samples and 36.8% environmental samples. The average count was 4.2 log cfu/g or mL, with a maximum value of 6.2 log cfu/g in a parsley sample. Leafy vegetables showed statistically significant higher mean counts than other vegetables. A total of 15 ESBL-producing isolates were obtained from vegetables (14) and water (1) samples and were identified as Serratia fonticola (11) and Rahnella aquatilis (4). Five isolates of S. fonticola were considered multi-drug resistant. Even though their implication in human infections is rare, they can become an environmental reservoir of antibiotic-resistance genes that can be further disseminated along the food chain.

The genus Aeromonas has received constant attention in different areas, from aquaculture and veterinary medicine to food safety, where more and more frequent isolates are occurring with increased resistance to antibiotics. The present paper studied the interaction of Aeromonas strains isolated from fresh produce and water with different eukaryotic cell types with the aim of better understanding the cytotoxic capacity of these strains. To study host-cell pathogen interactions in Aeromonas, we used HT-29, Vero, J774A.1, and primary mouse embryonic fibroblasts. These interactions were analyzed by confocal microscopy to determine the cytotoxicity of the strains. We also used Galleria mellonella larvae to test their pathogenicity in this experimental model. Our results demonstrated that two strains showed high cytotoxicity in epithelial cells, fibroblasts, and macrophages. Furthermore, these strains showed high virulence using the G. mellonella model. All strains used in this paper generally showed low levels of resistance to the different families of the antibiotics being tested. These results indicated that some strains of Aeromonas present in vegetables and water pose a potential health hazard, displaying very high in vitro and in vivo virulence. This pathogenic potential, and some recent concerning findings on antimicrobial resistance in Aeromonas, encourage further efforts in examining the precise significance of Aeromonas strains isolated from foods for human consumption.

Fresh produce represents a key interface in the One Health continuum, connecting environmental, agricultural and clinical settings where opportunistic bacteria can circulate. Among them, Stenotrophomonas comprises an environmental genus of growing concern due to its multidrug resistance and rising clinical relevance. To investigate their diversity and pathogenic potential, nineteen isolates from vegetables, irrigation water and hospital sources were characterized by MLST, growth kinetics, biofilm formation, antimicrobial susceptibility assays and whole-genome sequencing. Phylogenetic analyses grouped 12 isolates within the Stenotrophomonas maltophilia complex (SMC) (clinical S. maltophilia (n = 7) and environmental S. geniculata (n = 4) and S. sepilia (n = 1)) and seven non-SMC isolates, including S. indicatrix (n = 5) and two unclassified clinical strains. Environmental S. geniculata and S. sepilia isolates showed robust growth at 37 °C and biofilm formation comparable to clinical lineages. Genomic analyses further revealed shared mobile loci (afaD, fhaB, zot) and homologous plasmids between environmental and clinical isolates, suggesting a connected gene pool. The identification of environmental strains with virulence-associated traits and clinical-like phenotypes supports fresh produce as a potential reservoir and transmission route for opportunistic Stenotrophomonas, underscoring the need for integrated surveillance across the food–health interface.

Foods of animal origin are increasingly considered a source of extended spectrum β-lactamase (ESBL) producing bacteria which can disseminate throughout the food chain and become a health concern for humans. This work aimed to evaluate the occurrence of ESBL-producing Escherichia coli in 100 retail minced meat samples taken in markets in Pamplona, Colombia. A total of 19 ESBL-producing isolates were obtained, 18 identified as E. coli and one as E. fergusonii. Fifteen isolates (78.9 %) carried bla_CTX-M and bla_TEM genes, one (5.2 %) bla_SHV and bla_TEM genes, one isolate (5.2 %) carried bla_CTX-M and one (5.2 %) bla_SHV alone. The majority of CTX-M-positive E. coli isolates carried the bla_CTX-M-15 gene (13 isolates), being the bla_CTX-M-9, bla_CTX-M-2, and bla_CTX-M-8 (one isolate each) also detected. Two SHV-positive isolates presented the bla_SHV-5 and bla_SHV-12 allele. The isolate identified as E. fergusonii was positive for bla_CTX-M-65 gene and mcr-1 gene. Sixteen isolates (84.2 %) belonged to phylogroups A and B1 and grouped together in the phylogenetic tree obtained by MLST; phylogroups E and F were also detected. Transfer of ESBL resistance was demonstrated for the E. fergusonii isolate. Whole genome sequencing of this isolate revealed the presence of plasmids carrying additional resistance genes. This investigation showed the high prevalence of ESBL-producing E. coli in retail samples of minced meat. Also, the isolation of a strain of E. fergusonii is an additional concern, as some resistance genes are located in mobile elements, which can be transmitted to other bacteria. These evidences support the increasing public health concern considering the spreading of resistance genes through the food chain.

The presence of opportunistic pathogens, such as the Enterobacter cloacae complex (ECC), in fresh vegetables poses a significant health risk, particularly amid the ongoing antibiotic resistance crisis. Traditional chemical decontamination methods are often ineffective and these are associated with issues such as cross-resistance between antibiotics and biocides, highlighting the need for alternative approaches. This study describes the isolation of a novel phage, FENT2, with anti-ECC activity, obtained from cattle farm sewage. Belonging to the Seunavirus genus, FENT2 did not carry genes associated with lysogenic cycle, antimicrobial resistance, or virulence factors. The phage demonstrated lytic activity against the host strain E. kobei AG07E, which harbored the mcr-9 gene, exhibiting a narrow host range that also included E. ludwigii strains. In vitro assays using BioTrac (SY-LAB) impedance technology confirmed the sustained lytic activity of FENT2 under food-related stress conditions, including pH levels from 5 to 7 and NaCl concentrations up to 2%. Furthermore, FENT2 demonstrated bactericidal potential on lettuce leaves, achieving 1 log reduction in bacterial counts of the host strain after 30 min immersion treatment. These findings highlight FENT2 as a promising candidate for biocontrol applications, offering a sustainable alternative to conventional decontamination methods for reducing antimicrobial-resistant ECC contamination in fresh produce.

Cecina de León is a traditional Spanish dry-cured beef product whose surface, as in other similar meat products, becomes heavily colonised by fungi during ripening, raising concerns related to possible mycotoxin contamination. This study aimed to characterise the mycobiota associated with cecina and its production environment, with particular emphasis on mycotoxigenic Penicillium species. Seventy-eight cecina samples and 26 air samples were collected from meat-processing plants and local markets in the province of León (Spain) and analysed for fungal counts, water activity and pH. A total of 101 mould isolates and 16 yeasts were recovered, with Penicillium accounting for 88% of all moulds. Sixteen Penicillium species were identified using a polyphasic approach integrating macro- and micromorphological analysis, extrolite production, molecular markers (BenA, CaM and ITS), and MALDI-TOF MS. Mycotoxin screening by HPTLC and HPLC-PDA targeted cyclopiazonic acid, ochratoxin A, patulin, citrinin, griseofulvin and mycophenolic acid, revealing that 51% of the Penicillium isolates were mycotoxin producers, mainly P. commune. The proposed polyphasic strategy, including MALDI-TOF MS as a rapid complementary tool, offers a practical framework for the surveillance of fungal communities and mycotoxin risk in meat-processing environments.