Salmonellais one of the major foodborne pathogens worldwide. The antimicrobial resistance (AMR) of this foodborne pathogen has raised a great concern in recent years. Studies on the frequency and characterization ofSalmonellaserotypes can help to improve our knowledge on the epidemiology of this pathogen. The purpose of this study was to compare the serotypes, AMR and genetic profiles ofSalmonellaisolates recovered from raw beef throughout the beef production chain and from human feces associated with clinical cases of salmonellosis. The serotype, AMR and pulsed-field gel electrophoresis profile of 243Salmonella entericaisolates recovered from beef carcasses (n = 78), ground beef (n = 135), and human feces from clinical cases of salmonellosis (n = 30) were compared. Forty-three differentSalmonellaserotypes were identified and regardless of the source, the top five corresponded to Typhimurium, Give, Group B (partially serotyped), Infantis and Anatum. Twelve serotypes from beef carcasses were also found in ground beef, showing their presence throughout the beef production chain.SalmonellaTyphimurium, Infantis, Anatum and Montevideo were the only serotypes identified in all sample types. Resistance to tetracyclines was the most frequent (41.2%) followed by resistance to aminoglycosides (37%), folate pathway inhibitors (21%), quinolones (20.2%), phenicols (17.1%), penicillins (15.6%) and cephems (7%). Multidrug resistance was observed in 28.8% of the isolates, and those from human feces showed resistance to a larger number of antimicrobials. Great concern arises from the resistance and reduced susceptibility observed to quinolones and cephalosporins because these drugs are the first line of treatment for invasiveSalmonellainfections. Twenty-seven distinct pulse-types were detected among 238 isolates. Clustering analysis for the most frequent serotypes identified groups of isolates with similar AMR profiles. Multidrug resistance spreading throughout the food production chain should be continually monitored and its importance emphasized.

Hass avocados may become contaminated with Salmonella and Listeria monocytogenes at the farm and the packing facility or later during transportation and at retail. In Mexico, avocados are ... HIGHLIGHTS Avocados sold in retail markets in Mexico contain countable levels of microorganisms. Salmonella and L. monocytogenes were isolated from the surface of retail Hass avocados. Salmonella w...

Magnolia pugana (Iltis & A. Vazquez) A. Vázquez & Carvajal, an endemic Mexican species of the Magnoliaceae family, has received limited phytochemical and pharmacological attention. This study reports, for the first time, the chemical composition and in vitro bioactivities of essential oils (EOs) obtained from its leaves, flowers, and seeds. EOs were analyzed by gas chromatography–mass spectrometry (GC-MS) and flame ionization detection (GC-FID), revealing cyclocolorenone, a sesquiterpene, as the major compound (38–40%) across all plant parts. Antioxidant activity was evaluated using DPPH• and ABTS• radical scavenging assays, complemented by bioautographic thin-layer chromatography (TLC). Antibacterial activity was determined by minimum inhibitory concentration (MIC) against human pathogenic bacteria, while cytotoxicity was assessed in MCF-7 (breast) and HT-29 (colon) cancer cell lines. Seed and flower EOs exhibited the highest antioxidant activity, with IC₅₀ values of 21.5 mg/mL and 9.04 mg/mL, respectively. Strong antibacterial effects were observed against Gram-positive strains, particularly Staphylococcus epidermidis (MIC = 355.11 µg/mL) and S. aureus (MIC = 710.23 µg/mL). Leaf EO showed selective cytotoxicity toward MCF-7 cells (IC₅₀ = 27.25 µg/mL), while seed EO was most active against HT-29 cells (IC₅₀ = 54.01 µg/mL). These results suggest that M. pugana EOs, especially those from seeds, are a promising source of natural antioxidant, antimicrobial, and anticancer agents.

Sprouts are vehicles of foodborne diseases caused by pathogens such as Salmonella. The aim of this study was to evaluate thermal and chemical treatments applied as a hurdle approach to red... HIGHLIGHTS A hurdle approach reduces Salmonella concentration >5 log on alfalfa and broccoli seeds. Germination rates over 90% were reached on alfalfa and broccoli seeds after sequential treatments...

Global dissemination of emergent multidrug-resistant (MDR) Salmonella Infantis (ESI) is of great public health concern. ESI exhibits increased virulence and MDR phenotypes, features conferred by a conjugative megaplasmid (pESI-like). In Mexico, the potential circulation of ESI clones has been overlooked. This study assessed the structure, diversity, genomic features and transmission dynamics of Salmonella Infantis isolates ( n =191) from cattle, pigs, chickens, humans, surface waters and the environment from surveys conducted by research laboratories and government agencies in the 2008–2024 timeframe. Three genomic approaches were implemented: blast analysis, SNP-based phylogenetic analysis and ancestral state reconstruction analysis. The phylogeny divided the population into two divergent sublineages, based on the presence/absence of pESI-like plasmids. The apparently recent and massive acquisition of these plasmids had a profound impact at the population level, changing the proportion of isolates with MDR genotypes from 0 to 68%. Although ESI was mostly associated with chickens, it was also present in surface waters. In fact, our ancestral state reconstruction analysis showed that ESI likely evolved from surface water ancestors within poultry production environments. Most locally circulating ESI clones (73%) harbour resistance factors to 6–8 antibiotic classes, including extended-spectrum cephalosporins ( bla _CTX-M-65 ) and fluoroquinolones ( gyrA D87Y mutation), a feature shared with global ESI variants that we coined as CTX-M-gyrA 6-8. Control measures are urgently needed to prevent further dissemination of ESI, as well as the systematic surveillance of CTX-M-gyrA 6-8 clones, particularly in poultry, to reduce the risk of human exposure to this potentially deadly pathogen.