Research Publications (Food Safety)

The virulent genes expressed in Salmonella are one primary contributing factor leading to the high morbidity and mortality of salmonellosis in humans. This factor plays a role in infection of the host and transmission of disease. In this study, a total of 265 samples were collected from farmers' market in Xuzhou, Jiangsu Province, China, including 205 pork samples and 60 chicken samples.

Non-typhoidal Salmonella (NTS) strains are among the major foodborne pathogens with emerging multidrug-resistant phenotypes. In this study, antimicrobial susceptibilities of a collection of  Salmonella isolates (n=54) recovered from poultry and bivalve molluscs were performed. The study also investigated the virulence and resistance genes profiling as well as the phylogenetic relationships through PFGE and ERIC/PCR fingerprinting.

Background

Salmonellosis remains the second most common zoonosis in the European Union despite a long-term decreasing trend. However, this trend has been reported to have stagnated in recent years, particularly for Salmonella enterica serotype Enteritidis (SE).

Aim

One 25-kg dog produces about 500 g of excrement per day. Excrement is a potentially hazardous material, as it may contain pathogenic microorganisms. Our samples were tested for the presence of thermotolerant coliform bacteria, Enterococcus spp., Escherichia coli and Salmonella spp., which are indicators of faecal contamination, as well as for the presence of helminths and their eggs. During the experiment, it was observed whether these microorganisms could be eliminated by vermicomposting.

Salmonella enterica and Escherichia coli use the inner membrane transporter DctA to import the pyrimidine biosynthetic pathway intermediate orotate from the environment. To study the regulation of dctA expression, we used an S. enterica serovar Typhimurium pyrimidine auxotroph to select a mutant that could grow in an otherwise nonpermissive culture medium containing glucose and a low concentration of orotate.

by Rebecca Lavarini dos Santos, Emilia Fernanda Agostinho Davanzo, Joana Marchesini Palma, Virgílio Hipólito de Lemos Castro, Hayanna Maria Boaventura da Costa, Bruno Stéfano Lima Dallago, Simone Perecmanis, Ângela Patrícia Santana This study aimed to verify the presence of Listeria monocytogenes, Salmonella spp., and Escherichia coli in two Brazilian swine slaughterhouses, as well as to perform antibiograms, detect virulence and antimicrobial resistance genes,

We studied the biodegradation of oily sludge generated by a petroleum plant in Bahrain by a bacterial consortium (termed as AK6) under different bioprocess conditions. Biodegradation of petroleum hydrocarbons in oily sludge (C11-C29) increased from 24% after two days to 99% after 9 days of incubation in cultures containing 5% (w/v) of oily sludge at 40°C. When the nitrogen source was excluded from the batch cultures, hydrocarbon biodegradation dropped to 45% within 7 days.

Extended-spectrum β-lactamase (ESBL)-producing Salmonella enterica serovar Enteritidis has emerged as a public health concern. The main objectives of this study were therefore to determine the antimicrobial susceptibility profiles of Salmonella Enteritidis and to investigate the molecular characteristics of identified ESBL-producing isolates.

This study aimed to evaluate the synbiotic effect of probiotics and dried Spirulina platensis or phycocyanin on autoaggregation, coaggregation, and the inhibition of biofilm formation by Salmonella Typhimurium and Staphylococcus aureus on 96-well microtiter plates and Human colon carcinoma cells-116 surfaces. The results showed that the probiotics strains cultured in the presence of S.

Enteric infectious diseases account for more than a billion disease episodes yearly worldwide resulting in approximately 2 million deaths, with children under 5 years old and the elderly being disproportionally affected. Enteric pathogens comprise viruses, parasites, and bacteria; the latter including pathogens such as Salmonella [typhoidal (TS) and non-typhoidal (nTS)], cholera, Shigella and multiple pathotypes of Escherichia coli (E. coli).

Extensive studies have shown that potassium diformate (KDF), an antibiotic substitute used as a feed additive, improves animal growth performance, although there is less direct evidence of its preventive effect on bacterial infections and its influence on the intestinal flora of animals. In this study, the inhibition effect of KDF on Salmonella enterica serovar Pullorum, an important enteric pathogen causing pullorum disease, was investigated in vitro and on a chicken infection model.

We compared viability, morphology, enzyme activity and gene expression patterns between the chlorine tolerant S. Enteritidis RE 13 and the sensitive strain S. Enteritidis CVCC1806. As expected, viability of strain CVCC1806 was significantly lower than for RE 13 after exposure to 100 mg/L NaClO for 20 min and the sensitive strain displayed severe cell membrane damage and intracellular ATP depletion compared with the tolerant strain.

Cysteine (Cys) can rapidly and sensitively react with 12 polycytosine-templated silver nanoclusters (polyC12-AgNCs) via the formation of Ag–S bond and enhance the fluorescence of polyC12-AgNCs. Herein, a smart and enzyme-free biosensing platform for ultrasensitive detection of Salmonella Typhimurium (S. Typhimurium) has been constructed by the ingenious coupling of Y-shaped G-quadruplex DNAzyme (GQH DNAzyme) with polyC12-AgNCs.

Journal of Food Science, EarlyView. The high nutritional value of egg makes it vital to the human diet. Salmonella enteritidis is one of the major global causes of foodborne enteritis in humans. The chicken intestine is the main source of S. enteritidis. Therefore, eggs play an important role in the transmission of salmonellosis.

Non-typhoidal Salmonella (NTS) poses a global threat to public health. Poultry, one of the main reservoirs of NTS, is usually not clinically affected by most NTS, yet the economic losses to the poultry industry due to control and mitigation efforts, and due to negative publicity can be tremendous. NTS strains are routinely characterized into serotypes in a time-consuming, labor-intensive multistep process that requires skilled personnel.

In order to evaluate the potential and safety of lactic acid bacteria (LAB) isolated from faeces samples of Ganan yak as probiotic for prevention and/or treatment of yak diarrhea, four strains of LAB including Latilactobacillus curvatus (FY1), Weissella cibaria (FY2), Limosilactobacillus mucosae (FY3), and Lactiplantibacillus pentosus (FY4) were isolated and identified in this study.

Salmonella is a leading cause of foodborne illness worldwide and is a common concern in food safety. Salmonella enterica displaying resistance to extended-spectrum cephalosporins (ESCs) and fluoroquinolone (FQs) has been deemed a high-priority pathogen by the World Health Organization. Co-resistance to ESCs and FQs has been reported in S. enterica serovar Thompson (S. Thompson). However, the genetic context of ESCs and FQs resistance genes in S. Thompson lacks sufficient characterization.

Probiotic attributes of lactic acid bacteria isolated from goat and sheep milk samples were analysed by culturing them on an MRS agar medium. The most potential isolates, GMB24 and SMB16, were identified by biochemical tests which had ability to tolerate different concentrations of acid and bile and phenol resistance. They were further identified as Enterococcus faecium GMB24 and Enterococcus hirae SMB16 by 16S rRNA gene sequencing approach.

This study aimed to evaluate and model the antimicrobial action of different concentrations of Croton blanchetianus essential oil (CBEO) on the behavior of six bacterial species in vitro. CBEO extraction was performed by hydrodistillation and characterized by CG-MS.

New therapeutic strategies for clinical Salmonella enterica serovar Typhimurium (S. Typhimurium) infection are urgently needed due to the generation of antibiotic-resistant bacteria. Inhibition of bacterial virulence has been increasingly regarded as a potential and innovative strategy for the development of anti-infection drugs. Salmonella pathogenicity island (SPI)-encoded type III secretion system (T3SS) represents a key virulence factor in S.

mBio, Ahead of Print. For decades, the remote island nation of Samoa (population ~200,000) has faced endemic typhoid fever despite improvements in water quality, sanitation, and economic development. We recently described the epidemiology of typhoid fever in Samoa from 2008 to 2019 by person, place, and time; however, the local Salmonella enterica serovar Typhi (S. Typhi) population structure, evolutionary origins, and genomic features remained unknown.

Antimicrobial Agents and Chemotherapy, Ahead of Print. Frequent outbreaks of Salmonella Typhimurium infection, in both animal and human populations and with the potential for zoonotic transmission, pose a significant threat to the public health sector. The rapid emergence and spread of more invasive multidrug-resistant clinical isolates of Salmonella further highlight the need for the development of new drugs with effective broad-spectrum bactericidal activities.

Mechanism characterization on cross protection between different stresses is important for microbial intervention optimizations to ensuring food safety. In our previous work, ethanol adaptation was found to induce cross-protection against freezing stress in Salmonella Enteritidis. The current work aimed to uncover the underlying mechanisms of this phenomenon using proteomic and mutagenic techniques.

The objective of the present study was to compare the growth of food-pathogens Listeria monocytogenes, Salmonella enterica, food spoilage Bacillus subtilis, an industrial milk product isolate, and spore-forming Paenibacillus in commercially available ultrahigh temperature processed (UHT) bovine milk and non-dairy, plant-based beverages (coconut, almond, cashew) stored at chilled and ambient temperatures (4 °C, 8 °C or 20 °C).

Salmonella enterica serovar Typhimurium monophasic variants (Salmonella 4,[5],12:i:) has increased dramatically, causing human salmonellosis and colonization in pigs. With a difference to S. Typhimurium, the monophasic variants of S. Typhimurium lose the gene cassettes encoding the second phase flagellin.