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Food Science & Nutrition May 2024The aim of this study was to investigate the characteristics of yogurt prepared with the addition of Persian shallot and probiotic bacteria. The effect of Persian...
The aim of this study was to investigate the characteristics of yogurt prepared with the addition of Persian shallot and probiotic bacteria. The effect of Persian shallot on the viability of probiotic bacteria ( and ) was evaluated. Furthermore, the antimicrobial effects of shallot and probiotic bacteria on and species were investigated. The experiments were performed on days 0, 1, 7, 14, and 21. The results showed that the survival of lactic acid bacteria increased significantly in the presence of shallots ( < .05). The addition of two different probiotic bacteria to the yogurt samples inhibited the pathogenic bacteria. While bacteria had a 3-log reduction, did not grow at all in the presence of probiotic bacteria and shallots. Based on these experiments, it was concluded that the addition of shallots not only increased the survival of probiotic bacteria but also reduced the growth of food-borne pathogenic bacteria. In addition, the addition of probiotic bacteria increased the acceptance of sensory properties of yogurt samples.
PubMed: 38726396
DOI: 10.1002/fsn3.4036 -
Heliyon May 2024In this study, isolate 1-3 was selected out for its anti- Listeria potency, from which a novel circular bacteriocin, velezin, was purified out of the fermentate, and...
In this study, isolate 1-3 was selected out for its anti- Listeria potency, from which a novel circular bacteriocin, velezin, was purified out of the fermentate, and then characterized. Facilitated with a broad antibacterial spectrum, velezin has demonstrated decent inhibitive activity against of foodborne pathogen ATCC 19115. It exerted the antibacterial activity through damaging the membrane integrity of targeted cell and causing leakage of vital elements, including K ion. It was noteworthy that velezin also inhibited the biofilm formation by ATCC 19115. At the challenge of velezin, ATCC 19115 up-regulated expression of genes associated with membrane, ion transporters, stressing-related proteins as well as the genes responsible for the synthesis of small molecule. Taken together, velezin may have potential to be a candidate as natural additive used in food/feed in the future.
PubMed: 38726204
DOI: 10.1016/j.heliyon.2024.e29701 -
Heliyon May 2024Developing multifunctional nanomaterials through environmentally friendly and efficient approaches is a pivotal focus in nanotechnology. This study aimed to employ a...
Developing multifunctional nanomaterials through environmentally friendly and efficient approaches is a pivotal focus in nanotechnology. This study aimed to employ a biogenic method to synthesize multifunctional copper oxide nanoparticles (LI-CuO NPs) with diverse capabilities, including antibacterial, antioxidant, and seed priming properties, as well as photocatalytic organic dye degradation and wastewater treatment potentials using leaf extract. The synthesized LI-CuO NPs were extensively characterized using UV-vis spectroscopy, dynamic light scattering (DLS), X-ray diffraction (XRD), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and Fourier transform-infrared spectroscopy (FT-IR). The colloid displayed surface plasmon resonance peaks at 320 nm, characteristic of LI-CuO NPs. DLS analysis revealed an average particle size of 93.5 nm and a negative zeta potential of -20.3 mV. FTIR and XPS analyses demonstrated that LI-CuO NPs possessed abundant functional groups that acted as stabilizing agents. XRD analysis indicated pure crystalline and spherical LI-CuO NPs measuring 36 nm in size. Antibacterial tests exhibited significant differential activity of LI-CuO NPs against both gram-negative (, ) and gram-positive ( and ) bacteria. In antioxidant tests, the LI-CuO NPs demonstrated a remarkable radical scavenging activity of 97.6 % at a concentration of 400 μg mL. These nanoparticles were also found to enhance mustard seed germination at low concentrations. With a remarkable reusability, LI-CuO NPs exhibited excellent photocatalytic performance, with a degradation efficiency of 97.6 % at 150 μg/mL as well as a 95.6 % reduction in turbidity when applied to wastewater treatment. In conclusion, this study presents environmentally friendly method for the facile synthesis of LI-CuO NPs that could potentially offer promising applications in biomedicine, agriculture, and environmental remediation due to their multifunctional properties.
PubMed: 38726176
DOI: 10.1016/j.heliyon.2024.e30178 -
Heliyon May 2024The Contamination Sanitization Inspection and Disinfection (CSI-D) device is a handheld fluorescence-based imaging system designed to disinfect food contact surfaces...
The Contamination Sanitization Inspection and Disinfection (CSI-D) device is a handheld fluorescence-based imaging system designed to disinfect food contact surfaces using ultraviolet-C (UVC) illumination. This study aimed to determine the optimal CSI-D parameters (i.e., UVC exposure time and intensity) for the inactivation of the following foodborne bacteria plated on non-selective media: generic (indicator organism) and the pathogens enterohemorrhagic , enterotoxigenic , , and Each bacterial strain was spread-plated on non-selective agar and exposed to high-intensity (10 mW/cm) or low-intensity (5 mW/cm) UVC for 1-5 s. Control plates were not exposed to UVC. The plates were incubated overnight at 37 °C and then enumerated. Three trials for each bacterial strain were conducted. Statistical analysis was carried out to determine if there were significant differences in bacterial growth between UVC intensities and exposure times. Overall, exposure to low or high intensity for 3-5 s resulted in consistent inhibition of bacterial growth, with reductions of 99.9-100 % for , 96.8-100 % for , and 99.2-100 % for . The 1 s exposure time showed inconsistent results, with a 66.0-100 % reduction in growth depending on the intensity and bacterial strain. When the results for all strains within each species were combined, the 3-5 s exposure times showed significantly greater ( < 0.05) growth inhibition than the 1 s exposure time. However, there were no significant differences ( > 0.05) in growth inhibition between the high and low UVC intensities. The results of this study show that, in pure culture conditions, exposure to UVC with the CSI-D device for ≥3 s is required to achieve consistent reduction of and .
PubMed: 38726110
DOI: 10.1016/j.heliyon.2024.e30490 -
BMC Infectious Diseases May 2024We report a very rare case of Listeria multiple brain abscesses manifested as delirium, which represented diagnostic and therapeutic challenges overcome only by the...
We report a very rare case of Listeria multiple brain abscesses manifested as delirium, which represented diagnostic and therapeutic challenges overcome only by the close cooperation between Infectious Diseases and Neuroradiology, without which a satisfactory outcome would not be achieved.An elderly man presented with confusion and drowsiness with a background of type-II diabetes mellitus. Although computed tomography of the brain only showed frontal lobe oedema, contrast magnetic resonance (MR) imaging showed numerous irregular rim-enhancing lesions containing central diffusion restriction, suggesting multiple pyogenic cerebral abscesses of unclear aetiology. Thereafter, Listeria monocytogenes was isolated from blood cultures, suggesting this as the causative organism. Deemed unsuitable for neurosurgical drainage, the patient received medical management with a protracted course of antibiotics. This case was extremely challenging, due to 1) the impossibility of source control, 2) the small number of effective antibiotics available to treat this condition, and 3) the inevitable antibiotic side-effects, derived from long-term exposure. A successful outcome was only possible thanks to strict close multidisciplinary follow up, requiring frequent MR imaging and a judicious antibiotic choice, including monitoring of their side-effects. Due to the rarity of this condition, there is lack of guidance on its management, hence the importance of multidisciplinary involvement with very close imaging and antibiotic monitoring.
Topics: Humans; Male; Brain Abscess; Listeriosis; Anti-Bacterial Agents; Listeria monocytogenes; Aged; Magnetic Resonance Imaging; Tomography, X-Ray Computed; Brain; Delirium
PubMed: 38720244
DOI: 10.1186/s12879-024-09295-z -
RSC Advances May 2024Layered double hydroxides (LDH) are promising 2D nanomaterials being investigated for several engineering and biomedical applications. In this work, quinary Zr Al Fe Co...
Layered double hydroxides (LDH) are promising 2D nanomaterials being investigated for several engineering and biomedical applications. In this work, quinary Zr Al Fe Co Ni LDH and its Al Fe Co Ni LDH quaternary and Fe Co Ni LDH tertiary roots were prepared and characterized. All samples showed an aggregated, layered morphology with zero surface charge and approximately 300 nm of hydrodynamic size. BET surface area of Al Fe Co Ni LDH showed a remarkable value of 143.25 m g as opposed to 26.2 m g and 45.4 m g for Fe Co Ni LDH and Zr Al Fe Co Ni LDH, respectively. The antimicrobial activity of the prepared samples was assessed against the many pathogenic bacteria; () , () , () , () , () , and () , and six fungal species. Furthermore, anti-biofilm activity, growth curve assay, and effect of UV illumination were examined against various pathogenic microbes. Zr Al Fe Co Ni displayed remarkable antibacterial activity, as indicated by the lowest values of the minimum inhibitory concentrations (MIC) of 4-166.7 μg mL. Results for fungal strains varied in terms of their susceptibilities for the different samples tested. Zn Al Fe Co Ni was able to inhibit the biofilm formation of (96.09%), (98.32%), and () (95.93%). This study shown that certain LDH categories, particularly Zr Al Fe Co Ni, may be promising antibacterial agents against variety of pathogenic microorganisms that cause serious infections.
PubMed: 38716105
DOI: 10.1039/d4ra00508b -
BMC Microbiology May 2024The in-depth understanding of the role of lateral genetic transfer (LGT) in phage-prophage interactions is essential to rationalizing phage applications for human and...
Genetic recombination-mediated evolutionary interactions between phages of potential industrial importance and prophages of their hosts within or across the domains of Escherichia, Listeria, Salmonella, Campylobacter, and Staphylococcus.
BACKGROUND
The in-depth understanding of the role of lateral genetic transfer (LGT) in phage-prophage interactions is essential to rationalizing phage applications for human and animal therapy, as well as for food and environmental safety. This in silico study aimed to detect LGT between phages of potential industrial importance and their hosts.
METHODS
A large array of genetic recombination detection algorithms, implemented in SplitsTree and RDP4, was applied to detect LGT between various Escherichia, Listeria, Salmonella, Campylobacter, Staphylococcus, Pseudomonas, and Vibrio phages and their hosts. PHASTER and RAST were employed respectively to identify prophages across the host genome and to annotate LGT-affected genes with unknown functions. PhageAI was used to gain deeper insights into the life cycle history of recombined phages.
RESULTS
The split decomposition inferences (bootstrap values: 91.3-100; fit: 91.433-100), coupled with the Phi (0.0-2.836E-12) and RDP4 (P being well below 0.05) statistics, provided strong evidence for LGT between certain Escherichia, Listeria, Salmonella, and Campylobacter virulent phages and prophages of their hosts. The LGT events entailed mainly the phage genes encoding for hypothetical proteins, while some of these genetic loci appeared to have been affected even by intergeneric recombination in specific E. coli and S. enterica virulent phages when interacting with their host prophages. Moreover, it is shown that certain L. monocytogenes virulent phages could serve at least as the donors of the gene loci, involved in encoding for the basal promoter specificity factor, for L. monocytogenes. In contrast, the large genetic clusters were determined to have been simultaneously exchanged by many S. aureus prophages and some Staphylococcus temperate phages proposed earlier as potential therapeutic candidates (in their native or modified state). The above genetic clusters were found to encompass multiple genes encoding for various proteins, such as e.g., phage tail proteins, the capsid and scaffold proteins, holins, and transcriptional terminator proteins.
CONCLUSIONS
It is suggested that phage-prophage interactions, mediated by LGT (including intergeneric recombination), can have a far-reaching impact on the co-evolutionary trajectories of industrial phages and their hosts especially when excessively present across microbially rich environments.
Topics: Prophages; Recombination, Genetic; Campylobacter; Staphylococcus; Gene Transfer, Horizontal; Bacteriophages; Listeria; Salmonella; Evolution, Molecular; Bacteria
PubMed: 38704526
DOI: 10.1186/s12866-024-03312-6 -
Cell Systems May 2024The placenta is a selective maternal-fetal barrier that provides nourishment and protection from infections. However, certain pathogens can attach to and even cross the...
The placenta is a selective maternal-fetal barrier that provides nourishment and protection from infections. However, certain pathogens can attach to and even cross the placenta, causing pregnancy complications with potential lifelong impacts on the child's health. Here, we profiled at the single-cell level the placental responses to three pathogens associated with intrauterine complications-Plasmodium falciparum, Listeria monocytogenes, and Toxoplasma gondii. We found that upon exposure to the pathogens, all placental lineages trigger inflammatory responses that may compromise placental function. Additionally, we characterized the responses of fetal macrophages known as Hofbauer cells (HBCs) to each pathogen and propose that they are the probable niche for T. gondii. Finally, we revealed how P. falciparum adapts to the placental microenvironment by modulating protein export into the host erythrocyte and nutrient uptake pathways. Altogether, we have defined the cellular networks and signaling pathways mediating acute placental inflammatory responses that could contribute to pregnancy complications.
Topics: Humans; Female; Pregnancy; Placenta; Single-Cell Analysis; Plasmodium falciparum; Listeria monocytogenes; Toxoplasma; Macrophages; Toxoplasmosis; Inflammation
PubMed: 38703772
DOI: 10.1016/j.cels.2024.04.002 -
Listeria monocytogenes Contamination Leads to Survival and Growth During Enoki Mushroom Cultivation.Journal of Food Protection Jun 2024Two recent outbreaks of listeriosis have been linked to the consumption of enoki mushrooms. After the first outbreak, import sampling by the U.S. FDA identified that 43%...
Two recent outbreaks of listeriosis have been linked to the consumption of enoki mushrooms. After the first outbreak, import sampling by the U.S. FDA identified that 43% of the samples evaluated were positive for Listeria monocytogenes (Lm). These observations raised questions about the potential sources of Lm contamination of enoki mushrooms. One potential source of contamination is during enoki mushroom cultivation, as growing conditions are comparatively cool and moist to induce mushroom germination, to which Lm is well adapted. Two varieties of enoki mushrooms were evaluated to determine the potential for Lm to contaminate enoki cultures when introduced at various points during cultivation (inoculation, scraping, pinning, and collaring). The results of two trials showed that Lm established contamination and grew to similar levels in the substrate regardless of when Lm was introduced and, with one exception, did not alter the rate of mushroom generation to below the control. Enumeration of Lm in enoki mushroom cultures at harvest found an average contamination of 10 cfu/g, though the results were variable. Refrigerated storage for six weeks was found to result in an increase in Lm. Additionally, no statistically significant difference in the levels of Lm was observed based on proximity to the substrate, though levels of Lm in the different enoki samples correlated with levels of Lm in the substrate at harvest, but not at scraping. The ability of Lm to grow independently in the media used to culture enoki was assessed, and Lm was found to be unable to grow but could sporadically survive in Masters Mix. No growth of Lm was observed in potato dextrose broth, though growth could occur on the agar. Overall, the data indicate a high potential for the establishment of Lm contamination at any point during enoki cultivation to result in Lm-contaminated mushrooms. These data indicate a need for active control mechanisms to prevent the introduction of Lm to enoki cultures.
Topics: Listeria monocytogenes; Colony Count, Microbial; Food Contamination; Humans; Agaricales; Food Microbiology
PubMed: 38701973
DOI: 10.1016/j.jfp.2024.100290 -
Swiss Medical Weekly May 2024Listeriosis is a notifiable disease in Switzerland. In summer 2022, the Swiss Federal Office of Public Health noticed an increase in reports of listeriosis cases,...
AIMS OF THE STUDY
Listeriosis is a notifiable disease in Switzerland. In summer 2022, the Swiss Federal Office of Public Health noticed an increase in reports of listeriosis cases, indicating a possible ongoing outbreak. Here we present the approaches applied for rapidly confirming the outbreak, detecting the underlying source of infection and the measures put in place to eliminate it and contain the outbreak.
METHODS
For close surveillance and early detection of outbreak situations with their possible sources, listeriosis patients in Switzerland are systematically interviewed about risk behaviours and foods consumed prior to the infection. Listeria monocytogenes isolates derived from patients in medical laboratories are sent to the National Reference Laboratory for Enteropathogenic Bacteria and Listeria, where they routinely undergo whole-genome sequencing. Interview and whole-genome sequencing data are continuously linked for comparison and analysis.
RESULTS
In summer 2022, 20 patient-derived L. monocytogenes serotype 4b sequence type 388 strains were found to belong to an outbreak cluster (≤10 different alleles between neighbouring isolates) based on core genome multilocus sequence typing analysis. Geographically, 18 of 20 outbreak cases occurred in northeastern Switzerland. The median age of patients was 77.4 years (range: 58.1-89.7), with both sexes equally affected. Rolling analysis of the interview data revealed smoked trout from a local producer as a suspected infection source, triggering an on-site investigation of the production facility and sampling of the suspected products by the responsible cantonal food inspection team on 15 July 2022. Seven of ten samples tested positive for L. monocytogenes and the respective cantonal authority ordered a ban on production and distribution as well as a product recall. The Federal Food Safety and Veterinary Office released a nationwide public alert covering the smoked fish products concerned. Whole-genome sequencing analysis confirmed the interrelatedness of the L. monocytogenes smoked trout product isolates and the patient-derived isolates. Following the ban on production and distribution and the product recall, reporting of new outbreak-related cases rapidly dropped to zero.
CONCLUSIONS
This listeriosis outbreak could be contained within a relatively short time thanks to identification of the source of contamination through the established combined approach of timely interviewing of every listeriosis patient or a representative and continuous molecular analysis of the patient- and food-derived L. monocytogenes isolates. These findings highlight the effectiveness of this well-established, joint approach involving the federal and cantonal authorities and the research institutions mandated to contain listeriosis outbreaks in Switzerland.
Topics: Humans; Switzerland; Disease Outbreaks; Listeria monocytogenes; Listeriosis; Whole Genome Sequencing; Male; Aged; Female; Aged, 80 and over; Multilocus Sequence Typing; Middle Aged; Food Microbiology; Foodborne Diseases; Interviews as Topic
PubMed: 38701492
DOI: 10.57187/s.3745