Food pathogen

The Bacillus cereus group contains vertebrate pathogens such as Bacillus anthracis and Bacillus cereus and the invertebrate pathogen Bacillus thuringiensis. Microbial biopesticides based on B. thuringiensis (Bt) are widely recognized as being among the safest and least environmentally damaging insecticidal products available. Nevertheless, a recent food poisoning incident prompted a European Food Safety Authority review which argued that B. thuringiensis poses a health risk equivalent to B. cereus, a causative agent of diarrhoea...

AIMS: This study aimed to evaluate the biofilm formation and disinfectant resistance of Salmonella cells in mono- and dual-species biofilms with Pseudomonas aeruginosa, and to investigate the role of extracellular polymeric substances (EPS) in protection of biofilms against disinfection treatment. METHODS AND RESULTS: The populations of Salmonella in mono- or dual-species biofilms with P. aeruginosa on stainless steel (SS) coupons were determined before and after exposure to commercial disinfectant, 50 μg ml(-1) chlorine or 200 μg ml(-1) Ecolab(®) Whisper(™) V (a blend of four effective quaternary ammonium compounds)...

Probiotics have been proposed for a number of indications ranging from the hypothetical long-term immunomodulatory effects to proven benefits in the management of different clinical conditions.An increasing number of commercial products containing probiotics are available. In those products, irrespective if it is food, food supplement, medical food, or drug, the probiotic microorganisms have to be present in a sufficient number by the end of the shelf-life, to pass through the gastrointestinal tract resisting acid and bile, to colonize the gut, and to retain functional properties required to obtain the suggested beneficial effect...

The main reasons to improve the detection of Mycobacterium avium subsp. paratuberculosis (MAP) are animal health and monitoring of MAP entering the food chain via meat, milk, and/or dairy products. Different approaches can be used for the detection of MAP, but the use of magnetic separation especially in conjunction with PCR as an end-point detection method has risen in past years. However, the extraction of DNA which is a crucial step prior to PCR detection can be complicated due to the presence of inhibitory substances...

An endophytic fungus, MC_25L, has been isolated from the leaves of MonardacitriodoraCerv. ex Lag., a medicinal and aromatic herb from the northwestern Himalayas. It produces a fruity fragrance while growing on potato dextrose agar, suggesting that it is producing volatile organic compounds (VOCs). The endophyte inhibited the growth of plant pathogens such asSclerotiniasp. and Aspergillusflavus by virtue of VOCs. Identification of MC_25L based on morphological and microscopic features, as well as ITS-based rDNA sequence analysis, revealed that it is a Fusariumsp...

BACKGROUND: Plant fungal pathogens play a crucial role in the profitability, quality and quantity of plant production. These phytopathogens are persistent in avoiding plant defences causing diseases and quality losses around the world that amount to billions of US dollars annually. To control the scourge of plant fungal diseases, farmers have used fungicides to manage the damage of plant pathogenic fungi. Drawbacks such as development of resistance and environmental toxicity associated with these chemicals have motivated researchers and cultivators to investigate other possibilities...

Biofilms, which are complex microbial communities embedded in the protective extracellular polymeric substances (EPS), are difficult to remove in food production facilities. In this study, the use of acidic electrolyzed water (AEW) to remove foodborne pathogen biofilms was evaluated. We used a green fluorescent protein-tagged Escherichia coli for monitoring the efficiency of AEW for removing biofilms, where under the optimal treatment conditions, the fluorescent signal of cells in the biofilm disappeared rapidly and the population of biofilm cells was reduced by more than 67%...

Objectives: To investigate a set of MDR conjugative plasmids found in Vibrio species and characterize the underlying evolution process. Methods: pAQU-type plasmids from Vibrio species were sequenced using both Illumina and PacBio platforms. Bioinformatics tools were utilized to analyse the typical MDR regions and core genes in the plasmids. Results: The nine pAQU-type plasmids ranged from ∼160 to 206 kb in size and were found to harbour as many as 111 core genes encoding conjugative, replication and maintenance functions...

AIM: To isolate and characterize indigenous gluten hydrolyzing bacteria from wheat sourdough and curd samples and further evaluation of their probiotic potentiality. METHODS AND RESULTS: Indigenous gluten hydrolyzing isolates GS 33, GS 143, GS 181 and GS 188 were identified as Bacillus spp. by molecular-typing methods and studied extensively for their functional and probiotic attributes. All the tested isolates could survive at pH 2 and toxicity of 0.3% bile and also exhibited cell-surface hydrophobicity and autoaggregation phenotype...

Escherichia coli O157:H7 is an important foodborne pathogen that causes severe bloody diarrhea, hemorrhagic colitis, and hemolytic uremic syndrome. Ruminant manure is a primary source of E. coli O157:H7 contaminating the environment and food sources. Therefore, effective interventions targeted at reducing the prevalence of fecal excretion of E. coli O157:H7 by cattle and sheep and the elimination of E. coli O157:H7 contamination of meat products as well as fruits and vegetables are required. Bacteriophages offer the prospect of sustainable alternative approaches against bacterial pathogens with the flexibility of being applied therapeutically or for biological control purposes...

Innovation toward ecofriendly plant protection products compatible with sustainable agriculture and healthy food is today strongly encouraged. Here, we assessed the biocontrol activity of three cyclic lipopeptides from Bacillus subtilis (mycosubtilin, M; surfactin, S; fengycin, F) and two mixtures (M + S and M + S + F) on wheat against Zymoseptoria tritici, the main pathogen on this crop. Foliar application of these biomolecules at a 100-mg L(-1) concentration on the wheat cultivars Dinosor and Alixan, 2 days before fungal inoculation, provided significant reductions of disease severity...

Telavancin (TD-6424), a semisynthetic lipoglycopeptide vancomycin-derivative, is a novel antimicrobial agent developed by Theravance for overcoming resistant Gram-positive bacterial infections, specifically methicillin-resistant Staphylococcus aureus (MRSA). The US Food and Drug Administration (USFDA) had approved telavancin in 2009 for the treatment of complicated skin and skin structure infections (cSSSIs) caused by Gram-positive bacteria, including MRSA (S. aureus, Streptococcus agalactiae, Streptococcus pyogenes, Streptococcus anginosus group, or Enterococcus faecalis)...

Owing to the increase in the number of diseases affecting ducks and the demand for food safety by consumers, vaccination has become one of the factors that influence duck meat productivity. The highly pathogenic avian influenza (HPAI) virus is one of the most prevalent and causes one of the most lethal diseases in domestic ducks, and Salmonella enterica serovar Typhimurium is a food-borne pathogen persistent in the domestic duck population. To better understand the optimal usage of HPAI and S. enterica serovar Typhimurium vaccines, we aimed to determine antigen dose, oil and gel adjuvant usage with prime-boost regimen, and vaccination age, inducing the best immune response in ducks, without an effect on body weight gain...

Presence of ducks, and in particular of free-grazing ducks, has consistently been shown to be one of the most important risk factors for highly pathogenic avian influenza outbreaks which has compromised poultry production in South-East Asia since the early 2000s and continues to threaten public health, farmers' livelihood and food security. Although free-grazing duck production has been practised for decades in South-East Asia, there are few published studies describing this production system, which is suspected to play an important role in the maintenance of avian influenza viruses...

One of the key factors that determine the interaction between hosts and their parasites is the frequency of their interactions, which depends on the locomotory behavior of both parts. To address host behavior we used natural infections involving insect pathogenic nematodes and Drosophila melanogaster larvae as hosts. Using a modified version of a recently described method (FIMTrack) to assess several parameters in larger sets of animals, we initially detected specific differences in larval food searching when comparing Drosophila strains...

Because of their antagonistic activity towards pathogenic and spoilage bacteria, some members of the lactic acid bacteria (LAB) have been evaluated for use as food biopreservatives. The objectives of this study were to assess the antimicrobial utility of a commercial LAB intervention against O157 and non-O157 Shiga-toxigenic E. coli (STEC) on intact beef strip loins during refrigerated vacuum aging and determine intervention efficacy as a function of mode of intervention application. Prerigor strip loins were inoculated with a cocktail (8...

Staphylococcus saprophyticus is an important agent of urinary tract infection (UTI) in young women, but information about this pathogen in human microbiota and in common environment is lacking. The aim of this study was to characterize S. saprophyticus isolates from genitoanal microbiota of 621 pregnant women, 10 minas cheese packs, and five beaches in Rio de Janeiro city and compare PFGE profiles of these isolates with five UTI PFGE clusters described in this city. We investigated 65 S. saprophyticus isolates from microbiota, 13 from minas cheese, and 30 from beaches and 32 UTI isolates...

The aim of this work was to study the prevalence of Listeria monocytogenes in foods obtained in retail shops and food industries located in Montevideo-Uruguay, and to identify the serogroups of the obtained isolates. Three-thousand one-hundred and seventy-five food samples (frozen, deli meats, ready-to-eat and cheese) were analyzed. The obtained isolates were serogrouped by multiplex PCR and serotyped by conventional procedure. Genetic comparisons were performed using pulsed-field gel electrophoresis on a sub-set of isolates belonging to the same serotype successively recovered from the same establishment...

Destruxin A is among the major secondary metabolites produced by the entomopathogenic ascomycete Metarhizium sp., and the lack of studies concerning production of destruxin A by the fungus is most likely the biggest obstacle for the registration of new fungal strains. Although several studies focus on the production of destruxin A in culture media, few studies examine destruxin A in vivo during host infection. In the current work, Galleria mellonella was used as an insect model to develop for the first time in vivo real-time PCR- and HPLC-MS-based quantification of fungal growth and metabolite production, respectively, during infection by two strains of M...

Gastrointestinal disease is one of the most serious diseases in cultured seahorse juveniles. Treatment with antimicrobials of live food (i.e. copepods and Artemia) that is used to feed the juveniles may be a promising measure to alleviate the occurrence of gastrointestinal disease. However, relevant investigations are rare. In the present study, we first investigated the antimicrobial efficacies on bacteria within copepods that were treated with 4 antimicrobials, including 3 antibiotics (i.e. enrofloxacin hydrochloride, oxytetracycline and rifampicin [RFP]) that are approved for use in aquaculture and 1 disinfectant (i...