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Antibiotics (Basel, Switzerland) May 2024, a foodborne pathogen, exhibits high adaptability to adverse environmental conditions and is common in the food industry, especially in ready-to-eat foods. strains...
, a foodborne pathogen, exhibits high adaptability to adverse environmental conditions and is common in the food industry, especially in ready-to-eat foods. strains pose food safety challenges due to their ability to form biofilms, increased resistance to disinfectants, and long-term persistence in the environment. The aim of this study was to evaluate the presence and genetic diversity of in food and related environmental products collected from 2014 to 2022 and assess antibiotic susceptibility and biofilm formation abilities. was identified in 13 out of the 227 (6%) of samples, 7 from food products (meat preparation, cheeses, and raw milk) and 6 from food-processing environments (slaughterhouse-floor and catering establishments). All isolates exhibited high biofilm-forming capacity and antibiotic susceptibility testing showed resistance to several classes of antibiotics, especially trimethoprim-sulfamethoxazole and erythromycin. Genotyping and core-genome clustering identified eight sequence types and a cluster of three very closely related ST3 isolates (all from food), suggesting a common contamination source. Whole-genome sequencing (WGS) analysis revealed resistance genes conferring resistance to fosfomycin (), lincosamides (), fluoroquinolones (), and tetracycline (). In addition, the gene was also detected, conferring resistance to disinfecting agents and antiseptics. Virulence gene profiling revealed the presence of 92 associated genes associated with pathogenicity, adherence, and persistence. These findings underscore the presence of strains in food products and food-associated environments, demonstrating a high virulence of these strains associated with resistance genes to antibiotics, but also to disinfectants and antiseptics. Moreover, they emphasize the need for continuous surveillance, effective risk assessment, and rigorous control measures to minimize the public health risks associated to severe infections, particularly listeriosis outbreaks. A better understanding of the complex dynamics of pathogens in food products and their associated environments can help improve overall food safety and develop more effective strategies to prevent severe health consequences and economic losses.
PubMed: 38786175
DOI: 10.3390/antibiotics13050447 -
Emerging Infectious Diseases Jun 2024Food irradiation can reduce foodborne illnesses but is rarely used in the United States. We determined whether outbreaks related to Campylobacter, Salmonella,...
Food irradiation can reduce foodborne illnesses but is rarely used in the United States. We determined whether outbreaks related to Campylobacter, Salmonella, Escherichia coli, and Listeria monocytogenes were linked to irradiation-eligible foods. Of 482 outbreaks, 155 (32.2%) were linked to an irradiation-eligible food, none of which were known to be irradiated.
Topics: Humans; Disease Outbreaks; United States; Foodborne Diseases; Food Microbiology; Food Irradiation; History, 21st Century
PubMed: 38781985
DOI: 10.3201/eid3006.230922 -
International Journal of Food... Jul 2024In this study, 327 presumptive lactic acid bacteria (LAB) were isolated from goats' milk acid curds produced at a Sicilian dairy farm with the aim to identify potential...
Selection of starter lactic acid bacteria capable of forming biofilms on wooden vat prototypes for their future application in traditional Sicilian goat's milk cheese making.
In this study, 327 presumptive lactic acid bacteria (LAB) were isolated from goats' milk acid curds produced at a Sicilian dairy farm with the aim to identify potential starter cultures for traditional cheeses. All isolates were first processed by randomly amplified polymorphic DNA (RAPD)-PCR analysis. This approach identified 63 distinct strains which were evaluated for their acidifying capacity. Only 15 strains specifically stood out for their acidification capacity and were identified through 16S rRNA gene sequencing as Lactococcus lactis (11 strains) Enterococcus faecalis (three strains), and Ligilactobacillus animalis (one strain). Notably, all 15 LAB isolates produced bacteriocin-like inhibitory substances and anti-biofilm compounds, against both planktonic and biofilm forms of Listeria monocytogenes, Salmonella Enteritidis, Escherichia coli, and Staphylococcus aureus, albeit at varying levels. Among these 15 LAB, En. faecalis RGM25 and Lc. lactis RGM55, susceptible to five antibiotics tested, were put in contact with wooden vat prototypes, because all equipment used in traditional cheese production in Sicily are made of wood. Scanning electron microscopy and bacterial plate counts of the wooden vat prototypes showed the development of biofilms at levels of approximately 6.0 log CFU/cm. Overall, this study contributes to establishing a custom-made LAB starter cultures with bio-preservatives properties for Sicilian cheese productions.
Topics: Cheese; Animals; Biofilms; Goats; Milk; Wood; Food Microbiology; Sicily; Lactobacillales; RNA, Ribosomal, 16S; Anti-Bacterial Agents; Random Amplified Polymorphic DNA Technique; Listeria monocytogenes
PubMed: 38781647
DOI: 10.1016/j.ijfoodmicro.2024.110752 -
Biofilm Jun 2024is one of the leading causative agents of foodborne disease outbreaks worldwide. Herein, the antibiofilm effect and mechanism of Mannosylerythritol Lipid-A against...
is one of the leading causative agents of foodborne disease outbreaks worldwide. Herein, the antibiofilm effect and mechanism of Mannosylerythritol Lipid-A against EGD-e is reported for the first time. MEL-A effectively attenuated biofilm formation while reducing the viability and motility of bacteria within the biofilm in the early stage, and influenced bacterial adhesion by affecting the secretion of extracellular polysaccharides and eDNA. RT-qPCR revealed that MEL-A significantly suppressed the expression of genes involved in flagellar movement and virulence. Untargeted LC-MS metabolomics indicated that MEL-A affected the fluidity and permeability of cell membranes by significantly upregulating unsaturated fatty acids, lipids and glycoside metabolites, and affected protein biosynthesis, nucleotide metabolism and DNA synthesis and repair by significantly downregulating amino acid metabolism and nucleic acid metabolism. These pathways may constitute the key targets of biofilm formation inhibition by MEL-A. Furthermore, MEL-A showed good removal effects on mature biofilms under different temperatures, different materials and milk. Our data indicated that MEL-A could be used as a novel antibiofilm agent to improve food safety. Our study provides new insights into the possible inhibitory mechanism of MEL-A and the response of EGD-e to MEL-A.
PubMed: 38779407
DOI: 10.1016/j.bioflm.2024.100201 -
MSphere Jun 2024The placenta is a critical barrier against viral, bacterial, and eukaryotic pathogens. For most teratogenic pathogens, the precise molecular mechanisms of placental...
The placenta is a critical barrier against viral, bacterial, and eukaryotic pathogens. For most teratogenic pathogens, the precise molecular mechanisms of placental resistance are still being unraveled. Given the importance of understanding these mechanisms and challenges in replicating trophoblast-pathogen interactions using models, we tested an existing stem-cell-derived model of trophoblast development for its relevance to infection with . We grew human trophoblast stem cells (TS) under conditions leading to either syncytiotrophoblast (TS) or cytotrophoblast (TS) and infected them with . We evaluated proliferation and invasion, cell ultrastructure, as well as for transcriptome changes after infection. TS cells showed similar ultrastructure compared to primary cells and villous explants when analyzed by transmission electron microscopy and scanning electron microscopy (SEM), a resistance to adhesion could be visualized on the SEM level. Furthermore, TS were highly refractory to parasite adhesion and replication, while TS were not. RNA-seq data on mock-treated and infected cells identified differences between cell types as well as how they responded to infection. We also evaluated if TS-derived SYNs and CYTs had distinct resistance profiles to another vertically transmitted facultative intracellular pathogen, . We demonstrate that TS are highly resistant to , while TS are not. Like , TS resistance to was at the level of bacterial adhesion. Altogether, our data indicate that stem-cell-derived trophoblasts recapitulate resistance profiles of primary cells to and highlight the critical importance of the placental surface in cell-autonomous resistance to teratogens.IMPORTANCECongenital toxoplasmosis can cause a devastating consequence to the fetus. To reach the fetus's tissues, must cross the placenta barrier. However, how this parasite crosses the placenta and the precise molecular mechanisms of placental resistance to this parasite are still unknown. In this study, we aimed to characterize a new cellular model of human trophoblast stem cells to determine their resistance, susceptibility, and response to . Syncytiotrophoblast derived from trophoblast stem cells recapitulate the resistance profile similarly to placenta cells. We also showed that these cells are highly resistant to , at the level of bacterial adhesion. Our results suggest that resisting pathogen adhesion/attachment may be a generalized mechanism of syncytiotrophoblast resistance, and trophoblast stem cells represent a promising model to investigate cell-intrinsic mechanisms of resistance to pathogen adhesion and replication.
Topics: Trophoblasts; Toxoplasma; Humans; Listeria monocytogenes; Female; Pregnancy; Cell Adhesion; Placenta; Toxoplasmosis; Stem Cells
PubMed: 38771057
DOI: 10.1128/msphere.00748-23 -
Heliyon May 2024In the present study, growth potential of in steak tartare samples taken at retail and belonging to 13 brands marketed in Northern Italy was investigated. The samples...
In the present study, growth potential of in steak tartare samples taken at retail and belonging to 13 brands marketed in Northern Italy was investigated. The samples were submitted to microbiological and chemical-physical characterization. The data obtained were used as inputs for the application of the predictive microbiology software FSSP that allows the estimation of the growth of during the shelf-life. Lactic acid bacteria, the main component of the microflora, gave variable counts among the brands (from 3.38 to 6.24 log CFU/g). pH and a values were always higher than 5.3 and 0.96, respectively, thus they could not be considered as single efficient hurdles to prevent the growth of according to the EC Reg. 2073/2005; the same was observed for salt content (constantly <2 %) and nitrites (not quantifiable in all the samples, even if declared in some labels). Nevertheless, the combination of all the hurdles, evaluated by predictive microbiology using critical development factors, resulted in an estimated growth <0.5 log CFU/g throughout the shelf life; this output allowed us to consider all the steak tartare analysed as unfavourable substrate for growth. The information obtained could be useful for tartare producers as well as for competent authority to evaluate the effective risk concerning these typology of products.
PubMed: 38765030
DOI: 10.1016/j.heliyon.2024.e30883 -
Journal of Dairy Science May 2024The use of essential oils (EOs) has attracted interest in the food industry due to their wide range of beneficial properties. In this study, a new functional yogurt was...
The use of essential oils (EOs) has attracted interest in the food industry due to their wide range of beneficial properties. In this study, a new functional yogurt was developed using 2 essential oils [Marjoram (M) and Geranium (G)], at 3 different concentrations (0.2%, 0.4%, and 0.6% vol/vol). The physicochemical properties (syneresis, viscosity, pH, and chemical composition), bioactivities (antioxidant activity, anticancer and antibacterial effects, total phenolic content (TPC), and total flavonoid content (TFC)), and sensory characteristics of the developed yogurt were evaluated. The findings indicated that the yogurts fortified with 0.6% M or G exhibited higher viscosity and lower syneresis compared with other treatments. The yogurt supplemented with 0.6% M displayed significant antibacterial activity against Listeria monocytogenes, Staphylococcus aureus, Salmonella typhimurium, and Escherichia coli. In addition, the yogurt enriched with Geranium and Marjoram oils at a concentration of 0.6% had notably significant (P < 0.05) higher TFC levels compared with the control sample and other concentrations. In the same context, in terms of TPC, yogurt supplemented with 0.6% Marjoram oil displayed significantly (P < 0.05) elevated levels in comparison to the other samples tested. Yogurt enriched with Marjoram oil exhibited noteworthy antioxidant activity, followed by Geranium oil compared with the control samples. The yogurt supplemented with 0.6% M demonstrated strong radical scavenging activity, while the yogurt fortified with 0.6% G showed higher anticancer activity against HepG2 human liver carcinoma cells and oxidative stress enzyme activities. Among the various concentrations of EOs tested, the yogurts fortified with 0.6% M or G EOs exhibited the most favorable outcomes, followed by 0.4% M or G. To summarize, G and M EOs can be used as a potential nutritious ingredient and as a natural preservative for milk and related products.
PubMed: 38754824
DOI: 10.3168/jds.2023-24281 -
Analytical Chemistry May 2024In this study, the covalently fixed "end-on" orientation of a monoclonal antibody (mAb-) to amino terminated oligo (ethylene glycol)-capped gold nanoparticles...
In this study, the covalently fixed "end-on" orientation of a monoclonal antibody (mAb-) to amino terminated oligo (ethylene glycol)-capped gold nanoparticles (NH-TEG-AuNPs) was used to fabricate an in-house lateral flow strip (LFS), namely, the fixed "end-on" -mAb-NH-TEG-AuNPs LFS. The aim was to evaluate the performance of the fixed "end-on" -mAb-NH-TEG-AuNPs LFS in detecting . The proposed LFS enabled the sensitive detection of in 15 min with a visual limit of detection of 10 CFU/mL. Quantitative analysis indicated an LOD at 10 CFU/mL. The fixed "end-on" -mAb-NH-TEG-AuNPs LFS showed no cross-reactivity with other pathogenic bacteria and practical performance across different food matrices, including human blood, milk, and mushroom samples. Furthermore, the clinical performance of the fixed "end-on" -mAb-NH-TEG-AuNPs LFS for detecting was evaluated by using 12 clinical samples validated by the hemoculture method. It demonstrated excellent concordance with the reference methods, with no false-positive or false-negative results observed. Therefore, the fixed "end-on" -mAb-NH-TEG-AuNPs LFS serves as a promising candidate for a point-of-care test (POCT), enabling the rapid, precise, and highly sensitive detection of in clinical samples and contaminated food.
Topics: Listeria monocytogenes; Gold; Metal Nanoparticles; Antibodies, Monoclonal; Humans; Limit of Detection; Food Microbiology; Milk; Antibodies, Bacterial; Antibodies, Immobilized; Animals; Listeriosis
PubMed: 38748432
DOI: 10.1021/acs.analchem.4c00533 -
Cureus Apr 2024We present the case of a 62-year-old immunocompromised man with ulcerative colitis, primary sclerosing cholangitis, and cirrhosis treated with azathioprine and...
We present the case of a 62-year-old immunocompromised man with ulcerative colitis, primary sclerosing cholangitis, and cirrhosis treated with azathioprine and ustekinumab who quickly developed invasive infection after incidental identification on routine paracentesis. The infection rapidly progressed from bacterial peritonitis to bacteremia and meningitis within three days. Treatment with ampicillin and trimethoprim/sulfamethoxazole was successful. We highlight the increased risk of invasive listeriosis in immunocompromised individuals, including those on biologic therapies, and the importance of considering as a pathogen from sterile sites even in asymptomatic patients.
PubMed: 38738136
DOI: 10.7759/cureus.58116 -
Journal of Food Protection May 2024Field-packing of cantaloupes involves numerous food contact surfaces that can contamination melons with foodborne pathogens; the soil on these surfaces increases...
Field-packing of cantaloupes involves numerous food contact surfaces that can contamination melons with foodborne pathogens; the soil on these surfaces increases throughout the harvest day. Data is lacking on the cross-contamination risk from contaminated food contact surfaces under the dry conditions typical of cantaloupe field-packing operations. This study sought to evaluate the survival of Salmonella and Listeria monocytogenes on cantaloupe field-pack food contact surfaces using both a wet and dry inoculum to provide insights into managing foodborne pathogen contamination risks. Five clean or fouled materials (cotton gloves, nitrile gloves, rubber gloves, cotton rags, and stainless steel) were inoculated with a cocktail of either Salmonella or L. monocytogenes. A wet inoculum was spot inoculated (100 µL) onto coupons. A dry inoculum was prepared by mixing wet inoculum with 100 g of sterile sand, and shaking the coupons with the inoculated sand for 2min. Coupons were held at 35°C (35% RH) and enumerated at 0, 2, 4, 6 and 8 h. Significant differences in pathogen concentrations over time were calculated and the GInaFiT add-in tool for Excel was used to build Log-linear, Weibull, and Biphasic die-off models. Depending on the material type, coupon condition, and inoculum type, Salmonella and L. monocytogenes reductions over 8 h ranged from 0.3-3.3 and -0.4-4.2 log CFU/coupon, respectively. For all material types, Salmonella reductions were highest on wet-inoculated clean coupons; L. monocytogenes varied by material type. Weibull and biphasic models were a better fit of respective pathogen die-off curves than linear models. Overall, faster die-off rates were seen for wet inoculated and clean materials. Since pathogen populations remained viable over the study duration and both inoculum type and coupon condition impacted survival, frequent sanitation or replacement of food contact surfaces during the operational day is needed to reduce the risk of cross-contamination.
PubMed: 38734412
DOI: 10.1016/j.jfp.2024.100299