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Letters in Applied Microbiology

Sat, 03/03/2018 - 03:03
Abstract Shiga toxin-producing Escherichia coli (STEC) O157:H7 is a worldwide concern. Cattle are their main reservoir and may contaminate watercourses through manure. We characterized a collection of 38 STEC O157:H7 strains isolated from surface water in feedlots areas (puddles inside pens formed after the rainfall or by spill around drinking troughs, and small water courses and lagoons, formed...
Wed, 02/28/2018 - 08:20
Abstract Fresh-cut produce is at greater risk of Salmonella contamination. Detection and early warning systems play an important role in reducing the dissemination of contaminated products. One-step Reverse Transcription Polymerase Chain Reaction (RT-qPCR) targeting Salmonella tmRNA with or without a 6-h enrichment was evaluated for the detection of Salmonella in fresh-cut vegetables after 6-h...
Mon, 02/19/2018 - 02:15
Abstract Here, we hypothesized that the microbial gut flora of animals/pests living in polluted environments, produce substances to thwart bacterial infections. The overall aim of this study was to source microbes inhabiting unusual environmental niches for potential antimicrobial activity. Two cockroach species, Gromphadorhina portentosa (Madagascar) and Blaptica dubia (Dubia) were selected. The...
Wed, 02/14/2018 - 13:25
Abstract We produced a Pseudomonas veronii biofilm on the surface of stainless steel that is inhibitory to Escherichia coli O157:H7. P. veronii strain KACC 81051BP, isolated from lettuce, readily formed biofilm on the surface of stainless steel coupons (SSCs) immersed in tryptic soy broth at 25°C. Cells showed significantly (P ≤ 0∙05) enhanced tolerance to desiccation stress (43% relative...
Sat, 02/03/2018 - 14:50
Abstract Salmonella pathogenicity relies on virulence factors many of which are clustered within the Salmonella pathogenicity islands (SPIs). Salmonella also harbors mobile genetic elements such as virulence plasmids, prophage-like elements and antimicrobial resistance genes which can contribute to increase its pathogenicity. Here, we have genetically characterized a selected S. Typhimurium...
Tue, 01/30/2018 - 06:48
Abstract Iron availability plays an important role in the virulence of microorganisms, which develop different systems for iron acquisition. The expression of genes involved in iron uptake systems is usually regulated by Fur, a transcriptional regulator. Plesiomonas shigelloides is a Gram-negative food- and water-borne enteropathogen. Even though the mechanisms involved in the pathogenicity of...
Fri, 01/19/2018 - 09:15
Abstract The bioremediation of polycyclic aromatic hydrocarbon (PAH)-contaminated sites is not running smoothly, because of the lower activity of PAH-degrading bacteria in actual bioremediation applications. The phenomenon of “viable but non culturable” (VBNC) state may be a main limiting factor for their poor biodegradation capabilities of PAHs. Due to their abilities of entering into the VBNC...
Tue, 01/16/2018 - 17:11
Abstract Acetoacetate (AAA) was identified as a biofilm inhibitor in a previous study, where the effect of 190 carbon and nitrogen sources on biofilm amounts by Escherichia coli O157:H7 was determined. With this study, we tested the effect of AAA on growth and biofilm amounts of Cronobacter sakazakii, Serratia marcescens, and Yersinia enterocolitica. AAA reduced growth and biofilm amounts of the...
Sat, 01/13/2018 - 04:25
Abstract This study aimed to assess anthropogenic impact of surrounding population in the Private Reserve of Natural Heritage at Pantanal, the world's largest freshwater wetland ecosystem located in the center of South America. Viral etiologic agents of acute gastroenteritis as rotavirus A (RVA), noroviruses (NoV), human adenoviruses (HAdV), klassevirus (KV) and of hepatitis, as hepatitis A virus...
Thu, 12/28/2017 - 09:41
Abstract Extraction of pigments from endophytes is an uphill task. Up till now, there are no efficient methods available to extract the maximum amount of prodigiosin from Serratia marcescens. This is one of the important endophytes of Beta vulgaris L. The present work was carried out for the comparative study of six different extraction methods such as homogenization, ultrasonication, freezing...
Wed, 12/27/2017 - 18:50
Abstract Seafood has often been implicated in outbreaks of food-borne illness caused by Listeria monocytogenes but the source of contamination is usually not known. In this study we investigated the possibility that this pathogen could survive in seawater for an extended time period. Freshly collected seawater samples were inoculated with 1 x 108 CFU ml−1 of L. monocytogenes EGD-e and survival...
Fri, 12/22/2017 - 20:25
Abstract This study assess the quality of wastewater through the detection and quantification of important causing gastroenteritis viruses at different stages of the wastewater treatment process in an activated-sludge wastewater treatment plant with ultraviolet disinfection. Ten sampling events were carried out in a campaign along a period of 18 months collecting wastewater samples from the...
Sun, 12/17/2017 - 21:15
Abstract The importance of wild birds as potential vectors of disease has received recent renewed empirical interest, especially regarding human health although information regarding the enteropathogenic bacteria in birds of prey continue to be scant. This study was performed with the aim to evaluate the occurrence of enteropathogenic bacteria (i.e. Campylobacter spp. Escherichia coli, Salmonella...
Mon, 12/11/2017 - 02:00
Abstract In this work, fungi present in the grapevine's phyllosphere collected from the main demarcated wine regions of Portugal were identified, and their phylogenetic relationships were analysed. A total of 46 vine samples (leaves and berries) were collected from different parts of the country, being isolated a total of 117 fungal colonies that were identified to the genus level and sequenced...
Wed, 11/29/2017 - 03:01
Abstract The present study was undertaken to determine the mechanism of antibacterial activity of a polyphenolic fraction, composed of mainly catechin and isorhamnetin, previously isolated from Kombucha, a 14-day fermented beverage of sugared black tea, against the enteropathogen Vibrio cholerae N16961. Bacterial growth was found to be seriously impaired by the polyphenolic fraction in dose-...
Mon, 11/13/2017 - 10:05
Abstract The bacterial diversity and community structure involved in Chinese sauerkraut is one of the most important factors shaping the final characteristics of traditional foods. In this research, Lactobacillus casei 11MZ-5-1 was applied in Chinese sauerkraut fermentation as a starter culture. Illumina Miseq sequencing analysis was used to reveal the bacterial diversity and community structure...
Sat, 11/11/2017 - 08:45
Abstract The Andrias davidianus has been known as a traditional Chinese medicine for a long time. Its blood is considered as a waste or by-product of the meat production industry. Although there are reports on isolation of the antimicrobial peptides from different resources, there are no reports of their isolation from Andrias davidianus blood. In this work, an antimicrobial peptide, andricin B,...
Thu, 10/26/2017 - 05:20
Abstract The application of essential oils in form of nanoemulsions has been proposed as a method to improve their solubility in aqueous solutions, and hence their antimicrobial activity. The objective of this study was to evaluate the antimicrobial activity of citral, applied directly or in combined treatments with heat or pulsed electric fields (PEF), as a function of the inoculation procedure...
Tue, 10/24/2017 - 03:45
Abstract Fruit extracts from different tissues (pulp, seed and peel) have shown antimicrobial and prebiotic activities related to their phenolic profile, although structure-specific evaluations have not been reported yet. The effect of five phenolic compounds (catechin and gallic, vanillic, ferulic, and protocatechuic acids) identified in different fruits, particularly in mango, was evaluated on...
Wed, 09/27/2017 - 04:10
Abstract The aim of this research was to optimize two multiplex polymerase chain reaction (PCR) assays that could simultaneously detect six non–O157 Shiga toxin–producing Escherichia coli (STEC) as well as the three virulence genes. We also investigated the potential of combining the FTA™ card-based DNA extraction with the multiplex PCR assays. Two multiplex PCR assays were optimized using six...
Tue, 09/19/2017 - 21:35
Abstract A Strain DDB001 having an ability to remove deoxynivalenol (DON) was successfully isolated from wheat field soil. On the basis of phenotypic, genotypic and phylogenetic data, the strain DDB001 was identified as Paradevosia shaoguanensis. Strain DDB001 could grow well and thoroughly eliminate 200 mg l−1 of DON in complete growth medium, but it could not utilize DON as the sole carbon...
Sun, 09/03/2017 - 23:50
Abstract The current study is aimed to evaluate the mechanism of anthracene degradation by a bacterial strain isolated from fly ash deposition site near Jamadoba Coal Preparation Plant, Jharkhand, India. The Bushnell-Haas media cultured (containing anthracene as sole carbon source) bacterial isolate was identified by 16S rRNA gene sequence coding as the Bacillus thuringiensis strain, which showed...
Wed, 08/16/2017 - 05:30
Abstract The aim of the study was to evaluate possible antibacterial and antibiofilm efficacy of a bacteriocin, nisin with two essential oil components linalool and p-coumaric acid in combination against foodborne bacteria Bacillus cereus and Salmonella typhimurium. Their inhibition effects on planktonic cells and pre-formed biofilms were evaluated using microbroth dilution and checkerboard...
Sat, 08/12/2017 - 10:00
Abstract The presence of Salmonella spp. in halva has been associated with foodborne illnesses and product recalls from the markets. This study investigated the effect of environmental stresses on the survival of Salmonella spp. in halva during storage for 12 months at 10 and 25°C. Halva samples were inoculated with a cocktail of four strains of unstressed, desiccation stressed or heat stressed...
Fri, 07/14/2017 - 10:25
Abstract The objective of the present study was to assess the occurrence of major waterborne enteric viruses (enterovirus, norovirus, adenovirus, rotavirus, hepatitis A and E virus) along the Tiber River in Italy, in areas affected by different kinds of anthropogenic pressure (agricultural, urban, industrial, and pristine). Moreover, in light of the recent abundant detection of human bocavirus in...
Wed, 06/28/2017 - 04:15
Abstract Immunomagnetic separation used with culture based methods has been a useful technique in the detection of pathogens. However, previous studies have not answered many of the necessary questions for real world applications. The objective of this study was to assess the efficacy of different IMS bead types in recovery of the correct serogroup from a mixture of big six non-O157 STEC strains...
Tue, 06/20/2017 - 02:30
Abstract The qacC and lnuA genes of Staphylococcus species were recently proposed to comprise a mobile element when residing on rolling-circle plasmids. Here we present other examples of resistance genes on staphylococcal rolling-circle plasmids, including fosB producing resistance to fosfomycin, cat resulting in resistance to chloramphenicol, and cadB for resistance to the toxic heavy metal...
Tue, 06/13/2017 - 00:21
Abstract To determine the distribution of Norovirus (NoV) genotypes in natural river water in Thailand, we conducted a genome analysis using a next-generation sequencer. Twenty-five river water samples were collected at five different sites of the Khlong Klon River in the suburbs of Bangkok between August 2013 and December 2014. The partial genome of NoV was detected in 15 of the 25 samples (60·0...
Mon, 06/05/2017 - 23:55
Abstract A groEL gene-based loop-mediated isothermal amplification (LAMP) assay was developed to detect Vibrio parahaemolyticus in contaminated seafood and water. The assay was optimized and conducted at 63°C for 40 min using Bacillus stearothermophilus (Bst) DNA polymerase, large fragment. Amplification was analyzed via multiple detection methods, including opacity, formation of white...
Wed, 05/31/2017 - 01:45
AbstractArcobacter species are emerging food-borne and water-borne human pathogens associated mostly with food animals and their environment. The present study was aimed to isolate Arcobacter species from fish, shellfish and coastal water samples using two methods and to determine their genetic diversity. Of 201 samples of fish, shellfish and water samples analysed, 66 (32·8%) samples showed the...
Wed, 04/26/2017 - 03:05
Abstract Staphylococcus aureus (S. aureus) produces a wide variety of staphylococcal enterotoxins (SEs, SEA to SEX), which are responsible for staphylococcal food poisoning. This study is aimed to establish a system to detect SEM protein in food matrixes. In the present study, sem gene was characterized in a S. aureus isolate H4 associated with food poisoning. The amino acid sequence of the...
Mon, 04/17/2017 - 14:25
Abstract The influence of variable culture conditions on the size and wet density of spores of Bacillus cereus and Bacillus megaterium were examined in this work. Culture temperature and initial pH was shown to have a significant impact on the size of both species, with increasingly alkaline culture media and elevated culture temperatures resulting in spores that were, on average, up to 25%...
Tue, 04/11/2017 - 04:55
Abstract Internalisation of human pathogens in edible parts of vegetables eaten raw is a major concern, since once internalised they are protected from sanitising treatments. In this study, we examined invasion of gfp-labelled E. coli O157:H7 into intact and biotically (infection with Xanthomonas campestris/Pseudomonas syringae) and abiotically (grating with silicon carbide) damaged leaves of...
Fri, 04/07/2017 - 04:22
AbstractThis study evaluated the potential of probiotic bacteria to inhibit growth and cell adhesion of the bovine respiratory pathogen Mannheimia haemoltyica serotype 1. The inhibitory effects of nine probiotic strains (Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus helveticus, Lactobacillus plantarum, Lactobacillus rhamnosus, Lactococcus lactis, Streptococcus thermophilus and two...
Fri, 04/07/2017 - 04:22
AbstractMicrobiological source tracking (MST) for food industry is a rapid growing area of research and technology development. In this paper, a new library-independent approach for MST is presented. It is based on a high-throughput liquid microcultivation and FTIR spectroscopy. In this approach, FTIR spectra obtained from micro-organisms isolated along the production line and a product are...
Fri, 03/17/2017 - 06:55
Abstract Methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of severe healthcare-associated (HA) infections. Although during the last decade the incidence of HA invasive infections has dropped, the incidence of community-associated MRSA (CA-MRSA) infections has risen among the general population. Moreover, CA-MRSA, livestock-associated MRSA (LA-MRSA) and HA MRSA (HA-MRSA) can be...
Fri, 03/10/2017 - 10:55
Abstract The increase in the consumption of fresh produce has correlated with a rise in the number of reported foodborne illnesses. To identify potential risk factors associated with post-harvest practices, the present study employed multilocus sequence typing (MLST) for the genotypic classification of Escherichia coli isolates, recovered from three sources sampled at seven operational stages in...
Thu, 03/09/2017 - 03:20
Abstract Thirty-two lactic acid bacteria (LAB) isolates were obtained from fermenting cassava mash and wara (African soft cheese) and screened for their resistance to cadmium and lead toxicities at 550 to 1050 mg l−1 and probiotic potentials. Four LAB strains that tolerated the heavy metals at 1050 mg l−1 were selected for antioxidative capacities, tolerance to acid, bile salts and simulated...
Thu, 02/16/2017 - 19:35
Summary In the last years different surveillances have been published in Africa, especially in Northern countries, regarding antimicrobial resistance among husbandry animals. Information is still scarce, but the available data shows a worrying picture. Although the highest resistance rates have been described against tetracycline, penicillins and sulphonamides, prevalence of plasmid mediated...
Fri, 01/27/2017 - 15:15
Abstract The aim of this study was to analyze the growth kinetics of Listeria monocytogenes in naturally contaminated chilled pork. A cocktail of 26 meat-borne L. monocytogenes was inoculated to raw or sterile chilled pork to observe its growth at 4, 10, 16, 22 and 28 °C, respectively. The growth data were fitted by the Baranyi model and Ratkowsky square-root model. Results showed that the...
Thu, 01/19/2017 - 02:10
Abstract Listeria monocytogenes is a pathogenic bacterium, with human disease and infection linked to dairy products, seafood, ready-to-eat meat and raw & undercooked meats. Stainless steel is the most common food preparation surface and therefore, it is important to understand how food storage conditions such as surface materials, temperature and relative humidity can affect survival of L....
Wed, 01/18/2017 - 18:05
Abstract Food related carbohydrates and proteins are often used as thermoprotectant for probiotic lactobacilli during industrial production and processing. However, the effect of inorganic salts is rarely reported. Magnesium is the second-most abundant cation in bacteria, and commonly found in various foods. Mg2+ homeostasis is important in Salmonella and has been reported to play a critical role...
Fri, 12/30/2016 - 09:45
Abstract Limited data are available on the prevalence of livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) in the UK. We tested 124 raw meat samples for MRSA including pork (n=63), chicken (n=50) and turkey (n=11) collected from retail outlets in North West England between March and July 2015. MRSA was recovered from 9 (7.3%) samples (4 chicken, 3 pork, 2 turkey) from...
Mon, 12/26/2016 - 09:20
Abstract Clostridium perfringens epsilon toxin (ETX), staphylococcal enterotoxin B (SEB), and shiga toxin (STX) are implicated in a number of diseases and food-borne intoxications and are considered as potential agents for bioterrorism and warfare. Artificially generated aerosol is the likely mode of delivery of these toxins for nefarious uses; potentially capable of causing mass destruction to...
Sat, 12/17/2016 - 17:30
Abstract Pathogenic strains of Enterococcus cecorum (EC) expressing multidrug resistance have emerged. In National Antimicrobial Resistance Monitoring System (NARMS) data, EC is rarely recovered from chickens. Two NARMS methodologies (FDA, USDA) were compared with standard culture (SC) techniques for recovery of EC. NARMS methods failed to detect EC in 58 cecal samples, 20 chicken breast or 6...
Fri, 12/16/2016 - 00:10
Abstract A simplified method to produce specific polyclonal rabbit antibodies against sterigmatocystin (STC) was established, using a STC-glycolic acid-ether derivative (STC-GE) conjugated to keyhole limpet hemocyanin (immunogen). The competitive direct enzyme immunoassay (EIA) established for STC had a detection limit (20% binding inhibition) of 130 pg ml−1. The test was highly specific for STC...
Fri, 12/16/2016 - 00:05
Abstract The low energy of UV-A (315–400 nm) is insufficient for disinfection. To improve UV-A disinfection technology, the effect of ferulic acid (FA) addition on inactivation by UV-A light-emitting diode (LED) light (350–385 nm) was evaluated in the eliminating of suspensions of various food spoilers and pathogens (seven bacteria and four fungi). Photoantimicrobial assays were performed at FA...
Thu, 12/08/2016 - 15:45
Abstract Enterococcus faecium MXVK29 has the ability to produce an antimicrobial compound that belongs to Class IIa of the Klaenhammer classification, and could be used as part of a biopreservation technology through direct inoculation of the strain as a starter or protective culture. However, Enterococcus is considered an opportunistic pathogen, so the purpose of this work was to study the food...
Thu, 12/08/2016 - 15:35
Abstract Microbial dynamics on commercially grown white button mushrooms is of importance in terms of food safety assurance and quality control. The purpose of this study was to establish the microbial profile of fresh white button mushrooms. The total microbial load was determined through standard viable counts. Presence and isolation of gram-negative bacteria including coagulase positive...
Wed, 10/26/2016 - 09:00
Abstract Shigellosis represents a major burden of disease in developing countries. A low infectious dose allows the disease to be spread effectively. Although shigellosis is mostly a self-limiting disease, antibiotics are recommended to reduce deaths, disease symptoms, and organism-shedding time. However, In India, antimicrobial resistance among the genus Shigella is more common than among any...

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