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1.
Molecules ; 26(15)2021 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-34361842

RESUMO

A new preservation approach is presented in this article to prolong the lifetime of raw chicken meat and enhance its quality at 4 °C via coating with highly soluble kidney bean protein hydrolysate. The hydrolysates of the black, red, and white kidney protein (BKH, RKH, and WKH) were obtained after 30 min enzymatic hydrolysis with Alcalase (E/S ratio of 1:100, hydrolysis degree 25-29%). The different phaseolin subunits (8S) appeared in SDS-PAGE in 35-45 kD molecular weight range while vicilin appeared in the molecular weight range of 55-75 kD. The kidney bean protein hydrolysates have considerable antioxidant activity as evidenced by the DPPH-scavenging activity and ß-carotine-linolenic assay, as well as antimicrobial activity evaluated by disc diffusion assay. BKH followed by RKH (800 µg/mL) significantly (p ≤ 0.05) scavenged 95, 91% of DPPH and inhibited 82-88% of linoleic oxidation. The three studied hydrolysates significantly inhibited the growth of bacteria, yeast, and fungi, where BKH was the most performing. Kidney bean protein hydrolysates could shield the chicken meat because of their amphoteric nature and many functional properties (water and oil-absorbing capacity and foaming stability). The quality of chicken meat was assessed by tracing the fluctuations in the chemical parameters (pH, met-myoglobin, lipid oxidation, and TVBN), bacterial load (total bacterial count, and psychrophilic count), color parameters and sensorial traits during cold preservation (4 °C). The hydrolysates (800 µg/g) significantly p ≤ 0.05 reduced the increment in meat pH and TVBN values, inhibited 59-70% of lipid oxidation as compared to control during 30 days of cold storage via eliminating 50% of bacterial load and maintained secured storage for 30 days. RKH and WKH significantly (p ≤ 0.05) enhanced L*, a* values, thus augmented the meat whiteness and redness, while, BKH increased b* values, declining all color parameters during meat storage. RKH and WKH (800 µg/g) (p ≤ 0.05) maintained 50-71% and 69-75% of meat color and odor, respectively, increased the meat juiciness after 30 days of cold storage. BKH, RKH and WKH can be safely incorporated into novel foods.


Assuntos
Galinhas/microbiologia , Conservantes de Alimentos , Carne/microbiologia , Phaseolus/química , Hidrolisados de Proteína , Subtilisinas/química , Animais , Microbiologia de Alimentos , Conservantes de Alimentos/química , Conservantes de Alimentos/farmacologia , Hidrolisados de Proteína/química , Hidrolisados de Proteína/farmacologia
2.
Int J Food Microbiol ; 354: 109320, 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34229231

RESUMO

Campylobacter spp., such as Campylobacter jejuni and Campylobacter coli, are important zoonotic Gram-negative pathogens that cause acute intestinal diseases in humans. The optrA gene, encoding an ATP-binding cassette F (ABC-F) protein that confers resistance to oxazolidinones and phenicols, has been found in C. coli in China. In this study, the optrA gene was first identified in C. jejuni collected from retail meat in China from 2013 to 2016. Nine strains, isolated from a pigeon meat sample, carry the optrA gene. The molecular characteristics of the optrA-positive strains were determined by whole genome sequencing. Pulsed-field gel electrophoresis, multilocus sequence typing, and single nucleotide polymorphism analyses demonstrated that the nine optrA-positive isolates were genetically homogeneous. Phylogenetic characteristics and sequence comparison revealed that optrA was located on a chromosome-borne multidrug resistance genomic island. The optrA gene along with the tet(O) gene formed two different translocatable units (TUs), thereby supporting the transmission of TU-associated resistance genes. The emergence and spread of such TUs and strains are of great concern in terms of food safety, and measures must be implemented to avoid their dissemination in other Gram-negative bacteria and food chains.


Assuntos
Campylobacter jejuni , Columbidae , Resistência a Múltiplos Medicamentos , Ilhas Genômicas , Carne , Animais , Antibacterianos/farmacologia , Campylobacter jejuni/efeitos dos fármacos , Campylobacter jejuni/genética , Columbidae/microbiologia , Farmacorresistência Bacteriana/genética , Resistência a Múltiplos Medicamentos/genética , Ilhas Genômicas/genética , Humanos , Carne/microbiologia , Testes de Sensibilidade Microbiana , Filogenia
3.
Molecules ; 26(11)2021 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-34204052

RESUMO

The aim of this study was to evaluate the effect of the packaging system type on the physical characteristics and microbial changes in ostrich meat during refrigerated storage. The applied packaging systems were vacuum packaging (VP) and modified atmosphere packaging (MAP) using two combinations of gases: MAP1 (40% O2/40% CO2/20% N2) and MAP2 (60% O2/30% CO2/10% N2). Eight meat samples were obtained in three replicates for all parameters, except for pH, for which six replicates were obtained from the M. ilifibularis (IF) muscle, and were stored in a refrigerator at 2 °C and analyzed at 0, 4, 8, 12 and 16 days for the effect of packaging methods on physical meat quality. The initial pH (5.99) decreased at the end of the storage time for MAP1 to 5.81, whereas VP was stable from day 0 to 12 and increased up to 6.08 on day 16. Regarding meat color, the L* value increased during storage for MAP1 and MAP2 from 36.99 to 40.75 and 41.60, respectively, whereas it declined for VP to 34.22. The same tendencies were reported for redness (a*) and yellowness (b*). Drip loss was the lowest in MAP1 and highest in VP. The lowest total viable bacteria counts were identified in VP, as compared to MAP1 and MAP2.


Assuntos
Bactérias/crescimento & desenvolvimento , Embalagem de Alimentos/métodos , Armazenamento de Alimentos/métodos , Carne/análise , Struthioniformes , Animais , Atmosfera , Contagem de Colônia Microbiana , Microbiologia de Alimentos , Concentração de Íons de Hidrogênio , Carne/microbiologia , Viabilidade Microbiana , Refrigeração , Tempo , Vácuo
4.
Front Cell Infect Microbiol ; 11: 681588, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34327151

RESUMO

In this study, multidrug-resistant (MDR) Escherichia coli isolates from retail food and humans assigned into similar Multilocus Sequence Types (MLST) were analyzed using whole genome sequencing (WGS). In silico analysis of assembled sequences revealed the existence of multiple resistance genes among the examined E. coli isolates. Of the six CTX-M-producing isolates from retail food, bla CTX-M-14 was the prevalent variant identified (83.3%, 5/6). Two plasmid-mediated fosfomycin resistance genes, fosA3, and fosA4, were detected from retail food isolates (one each from chicken and beef), where fosA4 was identified in the chicken isolate 82CH that also carried the colistin resistance gene mcr-1. The bla CTX-M-14 and fosA genes in retail food isolates were located adjacent to insertion sequences ISEcp1 and IS26, respectively. Sequence analysis of the reconstructed mcr-1 plasmid (p82CH) showed 96-97% identity to mcr-1-carrying IncI2 plasmids previously identified in human and food E. coli isolates from Egypt. Hierarchical clustering of core genome MLST (HierCC) revealed clustering of chicken isolate 82CH, co-harboring mcr-1 and fosA4 genes, with a chicken E. coli isolate from China at the HC200 level (≤200 core genome allelic differences). As E. coli co-harboring mcr-1 and fosA4 genes has only been recently reported, this study shows rapid spread of this genotype that shares similar genetic structures with regional and international E. coli lineages originating from both humans and food animals. Adopting WGS-based surveillance system is warranted to facilitate monitoring the international spread of MDR pathogens.


Assuntos
Escherichia coli , Contaminação de Alimentos , Carne/microbiologia , Animais , Antibacterianos/farmacologia , Galinhas , China , Farmacorresistência Bacteriana Múltipla , Egito , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Proteínas de Escherichia coli/genética , Humanos , Tipagem de Sequências Multilocus , Plasmídeos/genética , beta-Lactamases/genética
5.
Food Microbiol ; 99: 103679, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34119089

RESUMO

Photobacterium spp. occur frequently in marine environments but have been recently also found as common spoilers on chilled meats. The environmental conditions in these ecological niches differ especially regarding salinity and ambient pressure. Linking the occurrence of photobacteria in different niches may elucidate its ecology and bring insights for the food industry. We investigated tolerance of Photobacterium (P.) phosphoreum and P. carnosum strains to high hydrostatic pressure and salinity and aligned our observations with presence of relevant genes. The strains were isolated from packaged meats and salmon (or the sea) to identify adaptations to marine and terrestrial habitats. Growth of all P. carnosum strains was reduced by 40 MPa hydrostatic pressure and >3% sodium chloride, suggesting loss of traits associated with marine habitats. In contrast, P. phosphoreum strains were only slightly affected, suggesting general adaptation to marine habitats. In accordance, these strains had gene clusters associated with marine niches, e.g. flagellar and lux-operons, being incomplete in P. carnosum. Occurrence of P. carnosum strains on packaged salmon and P. phosphoreum strains on meats therefore likely results from cross-contamination in meat and fish processing. Still, these strains showed intermediate traits regarding pressure- and halotolerance, suggesting developing adaptation to their respective environment.


Assuntos
Carne/microbiologia , Photobacterium/metabolismo , Salmão/microbiologia , Cloreto de Sódio/metabolismo , Animais , Bovinos , Galinhas , Microbiologia de Alimentos , Pressão Hidrostática , Photobacterium/química , Photobacterium/crescimento & desenvolvimento , Photobacterium/isolamento & purificação , Água do Mar/microbiologia , Cloreto de Sódio/análise
6.
Food Microbiol ; 99: 103804, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34119097

RESUMO

The effectiveness of three novel "host defence peptides" identified in human Apolipoprotein B (ApoB) as novel antimicrobial and antibiofilm agents to be employed in food industry is reported. ApoB-derived peptides have been found to exert significant antimicrobial effects towards Salmonella typhimurium ATCC® 14028 and Salmonella enteritidis 706 RIVM strains. Furthermore, they have been found to retain antimicrobial activity under experimental conditions selected to simulate those occurring during food storage, transportation and heat treatment, and have been found to be endowed with antibiofilm properties. Based on these findings, to evaluate the applicability of ApoB-derived peptides as food biopreservatives, coating solutions composed by chitosan (CH) and an ApoB-derived peptide have been prepared and found to be able to prevent Salmonella cells attachment to different kinds of surfaces employed in food industry. Finally, obtained coating solution has been demonstrated to hinder microbial proliferation in chicken meat samples. Altogether, obtained findings indicate that ApoB-derived peptides are promising candidates as novel biopreservatives for food packaging.


Assuntos
Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Apolipoproteínas B/química , Conservantes de Alimentos/farmacologia , Animais , Antibacterianos/química , Peptídeos Catiônicos Antimicrobianos/química , Galinhas , Embalagem de Alimentos , Conservação de Alimentos , Conservantes de Alimentos/química , Armazenamento de Alimentos , Carne/microbiologia , Testes de Sensibilidade Microbiana , Salmonella enteritidis/efeitos dos fármacos , Salmonella enteritidis/crescimento & desenvolvimento , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/crescimento & desenvolvimento
7.
Food Microbiol ; 99: 103822, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34119107

RESUMO

This study assessed the evolution of spoilage microbiota in association with the changes in pH and concentrations of lactic and acetic acids in retail oxygen-free modified atmosphere (30:70 CO2/N2) packages (MAP) of minced free-range chicken meat during storage at 4 °C for 10 days. MAP retarded growth of spoilage lactic acid bacteria (LAB) below 6.5 log cfu/g and fully suppressed growth of pseudomonads, enterobacteria, enterococci, staphylococci and yeasts. Two distinct Latilactobacillus sakei strain biotypes were predominant and Leuconostoc carnosum, Carnobacterium divergens, Latilactobacillus fuchuensis and Weissella koreensis were subdominant at spoilage. The chicken meat pH ranged from 5.8 to 6.1. l-lactate (832 mg/100 g on day-0) decreased slightly on day-7. d-lactate remained constantly below 20 mg/100 g, whereas acetate (0-59 mg/100 g) increased 5-fold on day-7. All MAP samples developed off-odors on day-7 and a strong 'blown-pack' sulfur-type of spoilage on day-10. However, neither the predominant Lb. sakei nor other LAB or gram-negative isolates formed H2S in vitro, except for C. divergens.


Assuntos
Bactérias/isolamento & purificação , Embalagem de Alimentos/métodos , Carne/microbiologia , Microbiota , Animais , Atmosfera/análise , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Galinhas/microbiologia , Contagem de Colônia Microbiana , Contaminação de Alimentos/análise , Embalagem de Alimentos/instrumentação , Armazenamento de Alimentos
8.
Food Microbiol ; 99: 103823, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34119108

RESUMO

Chickens play host to a diverse community of microorganisms which constitute the microflora of the live bird. Factors such as diet, genetics and immune system activity affect this complex population within the bird, while external influences including weather and exposure to other animals alter the development of the microbiome. Bacteria from these settings including Campylobacter and Salmonella play an important role in the quality and safety of end-products from these birds. Further steps, including washing and chilling, within the production cycle aim to control the proliferation of these microbes as well as those which cause product spoilage. These steps impose specific selective pressures upon the microflora of the meat product. Within the next decade, it is forecast that poultry meat, particularly chicken will become the most consumed meat globally. However, as poultry meat is a frequently cited reservoir of zoonotic disease, understanding the development of its microflora is key to controlling the proliferation of important spoilage and pathogenic bacterial groups present on the bird. Whilst several excellent reviews exist detailing the microbiome of poultry during primary production, others focus on fate of important poultry pathogens such as Campylobacter and Salmonella spp. At farm and retail level, and yet others describe the evolution of spoilage microbes during spoilage. This review seeks to provide the poultry industry and research scientists unfamiliar with food technology process with a holistic overview of the key changes to the microflora of broiler chickens at each stage of the production and retail cycle.


Assuntos
Bactérias/isolamento & purificação , Galinhas/microbiologia , Microbiota , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Galinhas/crescimento & desenvolvimento , Fazendas , Manipulação de Alimentos , Microbiologia de Alimentos , Carne/microbiologia
9.
Food Microbiol ; 99: 103828, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34119113

RESUMO

In this study, a composite film was prepared with bacterial cellulose (BC) of Gluconacetobacter xylinus and cell-free supernatant (CFS) of Enterococcus faecium TJUQ1, which was named BC-E. The optimum conditions for the preparation of the composite film with a minimal antibacterial activity were the soak of BC in 80 AU/mL CFS for 6 h. By scanning electron microscope observation, the surface network structure of BC-E was denser than that of BC. The tensile strength of BC and BC-E was 4.65 ± 0.88 MPa and 16.30 ± 0.92 MPa, the elongation at break of BC and BC-E was 3.33 ± 0.89% and 31.60 ± 1.15%, respectively, indicating the mechanical properties of BC-E were significantly higher than that of BC (P < 0.05). The swelling ratio of BC-E (456.67 ± 7.20%) was lower than that of BC (1377.78 ± 9.07%), demonstrating BC-E films presented better water resistance. BC-E films were soaked with 320 AU/mL CFS, and then used to pack the ground meat with 6.55 log10 CFU/g of Listeria monocytogenes. After 8 days of storage, the number of bacteria decreased by 3.16 log10 CFU/g. Similarly, total mesophilic bacterial levels in the ground meat decreased by 2.41 log10 CFU/g compared to control groups.


Assuntos
Antibacterianos/química , Celulose/química , Enterococcus faecium/metabolismo , Embalagem de Alimentos/instrumentação , Gluconacetobacter xylinus/metabolismo , Polímeros/química , Animais , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Hidrocarbonetos Aromáticos com Pontes/química , Hidrocarbonetos Aromáticos com Pontes/farmacologia , Celulose/metabolismo , Enterococcus faecium/química , Gluconacetobacter xylinus/química , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/crescimento & desenvolvimento , Carne/análise , Carne/microbiologia , Polímeros/farmacologia , Suínos , Resistência à Tração
10.
J Zoo Wildl Med ; 52(2): 858-862, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34130437

RESUMO

A 1-y-old female southern tamandua (Tamandua tetradactyla) presented with vomiting, hyporexia, and neurologic signs. Magnetic resonance imaging revealed contrast-enhancing material within the lateral and fourth ventricles and a T2 hyperintense cerebellar lesion, consistent with meningoencephalitis. The tamandua rapidly declined and was euthanatized. On gross postmortem exam, the tamandua had diffusely injected leptomeninges, opaque fluid in the fourth ventricle, and subdural brainstem and spinal cord hemorrhage. Histologically, there was regionally hemorrhagic and multifocal fibrinosuppurative meningoencephalomyelitis, ventriculitis, choroid plexitis, cerebellar folia necrosis, ependymitis, radiculoneuritis, and abundant intralesional gram-positive cocci. Streptococcus equi ssp. zooepidemicus was cultured from brain, cardiac blood clot, and multiple samples of horsemeat collected from the animal's diet. This is the first report of streptococcal meningoencephalomyelitis in a southern tamandua. The route of infection was likely gastrointestinal inoculation, which may have implications for the routine practice of feeding diets containing raw meat to insectivores.


Assuntos
Ração Animal/microbiologia , Encefalomielite/veterinária , Insetívoros , Carne/microbiologia , Infecções Estreptocócicas/veterinária , Streptococcus equi/isolamento & purificação , Animais , Dieta/veterinária , Encefalomielite/microbiologia , Encefalomielite/patologia , Evolução Fatal , Feminino , Microbiologia de Alimentos , Cavalos , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/patologia
11.
Int J Food Microbiol ; 349: 109202, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-33991875

RESUMO

The present work was carried out to understand the occurrence and antimicrobial susceptibility of Campylobacter spp., in various samples in Northern of Morocco. For this purpose, a random sampling was undertaken from butcher shops, traditional markets, and slaughterhouse. First, the research of Campylobacter was performed according to the Moroccan standard NM ISO: 10272-1 (2008). Second, the isolates were identified by biochemical tests and real time PCR. After the biochemical and molecular identification of suspected colonies, a disk diffusion method was executed to determine the sensitivity of Campylobacter spp. against 18 antibiotics. The results showed a moderate prevalence of Campylobacter species (130/466) recovered mainly on the Campylobacter blood base agar, where C. coli (108/130) were more prevalent comparable to C. jejuni (22/130) in poultry and cattle meat, raw milk, cloacal and surface swabs, and stool of patient suffering from diarrhea. The findings supported also the sensitivity of multiplex qPCR to detect Campylobacter strains compared to Moroccan standard NM ISO: 10272-1 (2008). Among our isolates, C. jejuni were the most susceptible strain toward colistin, florfenicol, gentamicin, streptomycin, and erythromycin. Nonetheless, the presence of multidrug Campylobacter resistant strains was highly observed in C. jejuni isolated, particularly, from broiler chickens toward the antibiotic classes of cephalosporin, penicillin, monobactam, quinolone, fluoroquinolone, sulfamide, as well as tetracycline. This may be due to common use of these drugs in veterinary medicine and farms as growth factor, which limits the usefulness of these molecules. Hence, the study highlights the importance of resistance profile monitoring of these pathogens in Northern of Morocco, in order to develop appropriate control measures and to reduce the emergence of multidrug-resistant strains.


Assuntos
Antibacterianos/farmacologia , Infecções por Campylobacter/microbiologia , Campylobacter/efeitos dos fármacos , Carne/microbiologia , Animais , Campylobacter/isolamento & purificação , Infecções por Campylobacter/epidemiologia , Bovinos , Galinhas , Farmacorresistência Bacteriana Múltipla , Fezes/microbiologia , Microbiologia de Alimentos , Humanos , Testes de Sensibilidade Microbiana , Leite/microbiologia , Marrocos/epidemiologia , Prevalência
12.
Int J Food Microbiol ; 349: 109232, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34022615

RESUMO

Biofilms are formed by microorganisms protected by a self-produced matrix, most often attached to a surface. In the food processing environments biofilms endanger the product safety by the transmission of spoilage and pathogenic bacteria. In this study, we characterised the biofilm formation of the following eleven strains isolated from biofilms in a meat-processing environment: Acinetobacter harbinensis BF1, Arthrobacter sp. BF1, Brochothrix thermosphacta BF1, Carnobacterium maltaromaticum BF1, Kocuria salsicia BF1, Lactococcus piscium BF1, Microbacterium sp. BF1, Pseudomonas fragi BF1, Psychrobacter sp. BF1, Rhodococcus erythropolis BF1, Stenotrophomonas sp. BF1. We applied whole- genome sequencing and subsequent genome analysis to elucidate genetic features associated with the biofilm lifestyle. We furthermore determined the motility and studied biofilm formation on stainless steel using a static mono-species biofilm model mimicking the meat processing environment. The biomass and the EPS components carbohydrates, proteins and extracellular DNA (eDNA) of the biofilms were investigated after seven days at 10 °C. Whole-genome analysis of the isolates revealed that all strains except the Kocuria salsicia BF1 isolate, harboured biofilm associated genes, including genes for matrix production and motility. Genes involved in cellulose metabolism (present in 82% of the eleven strains) and twitching motility (present in 45%) were most frequently found. The capacity for twitching was confirmed using plate assays for all strains except Lactococcus piscium BF1, which showed the lowest motility behaviour. Differences in biofilm forming abilities could be demonstrated. The bacterial load ranged from 5.4 log CFU/cm2 (Psychrobacter sp. isolate) to 8.7 log CFU/cm2 (Microbacterium sp. isolate). The amount of the matrix components varied between isolates. In the biofilm of six strains we detected all three matrix components at different levels (carbohydrates, proteins and eDNA), in two only carbohydrates and eDNA, and in three only carbohydrates. Carbohydrates were detected in biofilms of all strains ranging from 0.5 to 4.3 µg glucose equivalents/cm2. Overall, the Microbacterium sp. strain showed the highest biofilm forming ability with high bacterial load (8.7 log CFU/cm2) and high amounts of carbohydrates (2.2 µg glucose equivalents/cm2), proteins (present in all experiments) and eDNA (549 ng/cm2). In contrast, Brochothrix thermosphacta was a weak biofilm former, showing low bacterial load and low levels of carbohydrates in the matrix (6.2 log CFU/cm2 and 0.5 µg glucose equivalents/cm2). This study contributes to our understanding of the biofilm forming ability of bacteria highly abundant in the meat processing environment, which is crucial to develop strategies to prevent and reduce biofilm formation in the food producing environment.


Assuntos
Bactérias/isolamento & purificação , Biofilmes/crescimento & desenvolvimento , Carne/microbiologia , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Contagem de Colônia Microbiana , Matriz Extracelular de Substâncias Poliméricas/química , Matriz Extracelular de Substâncias Poliméricas/genética , Microbiologia de Alimentos , Indústria de Processamento de Alimentos , Genoma Bacteriano/genética , Locomoção/genética , Especificidade da Espécie
13.
Epidemiol Infect ; 149: e124, 2021 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-33955833

RESUMO

In August 2017, a cluster of four persons infected with genetically related strains of Shiga toxin-producing Escherichia coli (STEC) O157:H7 was identified. These strains possessed the Shiga toxin (stx) subtype stx2a, a toxin type known to be associated with severe clinical outcome. One person died after developing haemolytic uraemic syndrome. Interviews with cases revealed that three of the cases had been exposed to dogs fed on a raw meat-based diet (RMBD), specifically tripe. In two cases, the tripe had been purchased from the same supplier. Sampling and microbiological screening of raw pet food was undertaken and indicated the presence of STEC in the products. STEC was isolated from one sample of raw tripe but was different from the strain causing illness in humans. Nevertheless, the detection of STEC in the tripe provided evidence that raw pet food was a potential source of human STEC infection during this outbreak. This adds to the evidence of raw pet food as a risk factor for zoonotic transmission of gastrointestinal pathogens, which is widely accepted for Salmonella, Listeria and Campylobacter spp. Feeding RMBD to companion animals has recently increased in popularity due to the belief that they provide health benefits to animals. Although still rare, an increase in STEC cases reporting exposure to RMBDs was detected in 2017. There has also been an increased frequency of raw pet food incidents in 2017, suggesting an increasing trend in potential risk to humans from raw pet food. Recommendations to reduce the risk of infection included improved awareness of risk and promotion of good hygiene practices among the public when handling raw pet food.


Assuntos
Infecções por Escherichia coli/microbiologia , Escherichia coli O157/isolamento & purificação , Animais de Estimação , Alimentos Crus/microbiologia , Animais , Dieta/veterinária , Surtos de Doenças , Cães , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/transmissão , Escherichia coli O157/genética , Manipulação de Alimentos , Microbiologia de Alimentos , Síndrome Hemolítico-Urêmica/epidemiologia , Síndrome Hemolítico-Urêmica/microbiologia , Humanos , Carne/microbiologia , Toxina Shiga/genética , Zoonoses/epidemiologia , Zoonoses/microbiologia , Zoonoses/transmissão
14.
Int J Food Microbiol ; 348: 109208, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-33940536

RESUMO

Microbiological spoilage of meat is considered as a process which involves mainly bacterial metabolism leading to degradation of meat sensory qualities. Studying spoilage requires the collection of different types of experimental data encompassing microbiological, physicochemical and sensorial measurements. Within this framework, the objective herein was to carry out a multiblock path modelling workflow to decipher causality relationships between different types of spoilage-related responses: composition of microbiota, volatilome and off-odour profiles. Analyses were performed with the Path-ComDim approach on a large-scale dataset collected on fresh turkey sausages. This approach enabled to quantify the importance of causality relationships determined a priori between each type of responses as well as to identify important responses involved in spoilage, then to validate causality assumptions. Results were very promising: the data integration confirmed and quantified the causality between data blocks, exhibiting the dynamical nature of spoilage, mainly characterized by the evolution of off-odour profiles caused by the production of volatile organic compounds such as ethanol or ethyl acetate. This production was possibly associated with several bacterial species like Lactococcus piscium, Leuconostoc gelidum, Psychrobacter sp. or Latilactobacillus fuchuensis. Likewise, the production of acetoin and diacetyl in meat spoilage was highlighted. The Path-ComDim approach illustrated here with meat spoilage can be applied to other large-scale and heterogeneous datasets associated with pathway scenarios and represents a promising key tool for deciphering causality in complex biological phenomena.


Assuntos
Bactérias/metabolismo , Produtos da Carne/microbiologia , Carne/microbiologia , Compostos Orgânicos Voláteis/análise , Animais , Bactérias/classificação , Microbiologia de Alimentos , Embalagem de Alimentos , Lactococcus/metabolismo , Leuconostoc/metabolismo , Microbiota , Odorantes/análise , Psychrobacter/metabolismo , Perus/microbiologia
15.
World J Microbiol Biotechnol ; 37(5): 82, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33855623

RESUMO

Many volatile compounds secreted by bacteria play an important role in the interactions of microorganisms, can inhibit the growth of phytopathogenic bacteria and fungi, can suppress or stimulate plant growth and serve as infochemicals presenting a new type of interspecies communication. In this work, we investigated the effect of total pools of volatile substances and individual volatile organic compounds (VOCs) synthesized by the rhizosphere bacteria Pseudomonas chlororaphis 449 and Serratia plymuthica IC1270, the soil-borne strain P. fluorescens B-4117 and the spoiled meat isolate S. proteamaculans 94 on Arabidopsis thaliana plants. We showed that total gas mixtures secreted by these strains during their growth on Luria-Bertani agar inhibited A. thaliana growth. Hydrogen cyanide synthesis was unnecessary for the growth suppression. A decrease in the inhibition level was observed for the strain P. chlororaphis 449 with a mutation in the gacS gene, while inactivation of the rpoS gene had no effect. Individual VOCs synthesized by these bacteria (1-indecene, ketones 2-nonanone, 2-heptanone, 2-undecanone, and dimethyl disulfide) inhibited the growth of plants or killed them. Older A. thaliana seedlings were more resistant to VOCs than younger seedlings. The results indicated that the ability of some volatiles emitted by the rhizosphere and soil bacteria to inhibit plant growth should be considered when assessing the potential of such bacteria for the biocontrol of plant diseases.


Assuntos
Arabidopsis/efeitos dos fármacos , Pseudomonas chlororaphis/química , Pseudomonas chlororaphis/genética , Pseudomonas fluorescens/química , Serratia/química , Compostos Orgânicos Voláteis/toxicidade , Arabidopsis/crescimento & desenvolvimento , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Cianeto de Hidrogênio/metabolismo , Carne/microbiologia , Mutação , Pseudomonas chlororaphis/metabolismo , Pseudomonas fluorescens/metabolismo , Rizosfera , Plântula/efeitos dos fármacos , Serratia/metabolismo , Fator sigma/genética , Fator sigma/metabolismo , Microbiologia do Solo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Compostos Orgânicos Voláteis/química
16.
J Microbiol Biotechnol ; 31(5): 733-739, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-33820890

RESUMO

Acinetobacter strains are widely present in the environment. Some antimicrobial-resistant strains of this genus have been implicated in infections acquired in hospitals. Genetic similarities have been reported between Acinetobacter strains in nosocomial infections and those isolated from foods. However, the antimicrobial resistance of Acinetobacter strains in foods, such as meat, remains unclear. This study initially aimed to isolate Campylobacter strains; instead, strains of the genus Acinetobacter were isolated from meat products, and their antimicrobial resistance was investigated. In total, 58 Acinetobacter strains were isolated from 381 meat samples. Of these, 32 strains (38.6%) were from beef, 22 (26.5%) from pork, and 4 (4.8%) from duck meat. Antimicrobial susceptibility tests revealed that 12 strains were resistant to more than one antimicrobial agent, whereas two strains were multidrug-resistant; both strains were resistant to colistin. Cephalosporin antimicrobials showed high minimal inhibitory concentration against Acinetobacter strains. Resfinder analysis showed that one colistin-resistant strain carried mcr-4.3; this plasmid type was not confirmed, even when analyzed with PlasmidFinder. Analysis of the contig harboring mcr-4.3 using BLAST confirmed that this contig was related to mcr-4.3 of Acinetobacter baumannii. The increase in antimicrobial resistance in food production environments increases the resistance rate of Acinetobacter strains present in meat, inhibits the isolation of Campylobacter strains, and acts as a medium for the transmission of antimicrobial resistance in the environment. Therefore, further investigations are warranted to prevent the spread of antimicrobial resistance in food products.


Assuntos
Acinetobacter/efeitos dos fármacos , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Carne/microbiologia , Acinetobacter/genética , Acinetobacter/isolamento & purificação , Animais , Campylobacter/isolamento & purificação , Bovinos , Colistina/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/genética , Microbiologia de Alimentos , Genes Bacterianos , Testes de Sensibilidade Microbiana , Aves Domésticas/microbiologia , Alimentos Marinhos/microbiologia , Suínos
17.
Food Microbiol ; 98: 103768, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33875204

RESUMO

Game birds may carry zoonotic bacteria in their intestines and transmit them to hunters through bird handling or through the handling and consumption of contaminated meat. In this study, the prevalence of foodborne bacteria was screened from game bird faeces and mallard breast meat using PCR. The sampling occurred in southern Finland from August to December during the hunting season. Isolates were characterized by multi-locus sequence typing. Mesophilic aerobic bacteria and Escherichia coli counts were used to assess the microbial contamination of mallard meat. In total, 100 woodpigeon (Columba palumbus), 101 pheasants (Phasianus colchicus), 110 mallards (Anas platyrhynchos), and 30 teals (Anas crecca) were screened during the hunting season. Additionally, 100 mallard breast meat samples were collected. Campylobacter and Listeria were commonly detected in the faeces and Listeria on mallard meat. L. monocytogenes of sequence types associated with human listeriosis were frequently found in game bird faeces and on mallard meat. Good hygiene during game bird handling, storing the game bird meat frozen, and proper heat treatment are important measures to minimize the health risk for hunters and consumers.


Assuntos
Bactérias/isolamento & purificação , Infecções Bacterianas/microbiologia , Zoonoses Bacterianas/microbiologia , Aves/microbiologia , Doenças Transmitidas por Alimentos/microbiologia , Animais , Animais Selvagens/classificação , Animais Selvagens/microbiologia , Bactérias/classificação , Bactérias/genética , Infecções Bacterianas/metabolismo , Infecções Bacterianas/transmissão , Zoonoses Bacterianas/metabolismo , Zoonoses Bacterianas/transmissão , Aves/classificação , Fezes/microbiologia , Finlândia , Contaminação de Alimentos/análise , Doenças Transmitidas por Alimentos/metabolismo , Humanos , Carne/microbiologia , Tipagem de Sequências Multilocus
18.
Food Microbiol ; 98: 103769, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33875205

RESUMO

The transfer of blown pack spoilage causing Clostridium spores from the farm to the meat plant is of growing concern to the meat industry. This study investigated the environmental niches of these Clostridium spp., specifically Clostridium estertheticum and Clostridium gasigenes in the beef and sheep farm environments in New Zealand. Faecal, soil, grass, drinking water, puddle water and feed (fodder beet, hay, bailage and silage, where available) samples were collected on five beef and sheep farms during Winter and Spring in 2018, in North and South Island, respectively. Beef and sheep farm samples were tested for C. estertheticum and C. gasigenes using enrichment plus PCR, qPCR and direct plating. C. estertheticum was detected in bovine faecal (4%), soil (2-18%) and grass (0-12%) samples at concentration of up to 2.0 log10 cfu/g. C. gasigenes were found in 18-46% of faecal, 16-82% of soil, 12-44% of grass, 0-44.4% of drinking water and 0-58.3% of puddle water samples tested and the direct counts ranged from 2.4 log10 cfu/ml in puddle water to 3.4 log10 cfu/g in soil. C. estertheticum were detected by qPCR in sheep farms in ovine feces (2.3%), soil (2.3%) and fodder beet (10%). All other sample types (grass, drinking water, puddle water, baleage, hay, silage and fodder beet) were negative using direct and enrichment plus PCR methods. In contrast C. gasigenes was detected in of faecal (22.7-38.6%), soil (22.7-84.1%), grass (17.5-34.1%) drinking water (35.7-78.6%), puddle water (33.3-40%), hay baleage (57%), silage (2%) and fodder beet (10%) at concentrations of up to 3.7 log10 cfu/g/ml. It was concluded that C. estertheticum and C. gasigenes were common on beef and sheep farms with the latter having higher incidence and mean concentration.


Assuntos
Clostridium/crescimento & desenvolvimento , Microbiologia Ambiental , Carne/microbiologia , Matadouros , Criação de Animais Domésticos , Animais , Bovinos , Clostridium/classificação , Clostridium/genética , Clostridium/isolamento & purificação , Fazendas , Fezes/microbiologia , Contaminação de Alimentos/análise , Embalagem de Alimentos/instrumentação , Embalagem de Alimentos/métodos , Carne/análise , Nova Zelândia , Reação em Cadeia da Polimerase em Tempo Real , Estações do Ano , Ovinos
19.
Food Microbiol ; 98: 103781, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33875209

RESUMO

An increasing proportion of Clostridioides difficile infections (CDI) are community acquired. This study tested farm, abattoir and retail food samples for C. difficile, using peer reviewed culture and molecular methods. The contamination rate on beef, sheep and broiler farms ranged from 2/30 (7%) to 25/30 (83%) in faeces, soil and water samples, while concentrations ranged from 2.9 log10 cfu/ml to 8.4 log10 cfu/g. The prevalence and associated counts were much lower in abattoir samples. Although 26/60 were C. difficile positive by enrichment and PCR, only 6 samples yielded counts by direct plating (1.1 log10 cfu/cm2 to 5.1 log10 cfu/g). At retail, 9/240 samples were C. difficile positive, including corned beef (1), spinach leaves (2), iceberg lettuce, little gem lettuce, wild rocket, coleslaw, whole milk yogurt and cottage cheese (1 sample each), with counts of up to 6.8 log10 cfu/g. The tcdA, tcdB, cdtA, cdtB, tcdC and tcdR genes were detected in 41%, 99.2%, 33.6%, 32%, 46.7% and 31.1%, respectively, of the 122 C. difficile isolates obtained. It was concluded that although the prevalence of C. difficile decreased along the food chain, retail foods were still heavily contaminated. This pathogen may therefore be foodborne, perhaps necessitating dietary advice for potentially vulnerable patients.


Assuntos
Clostridioides difficile/isolamento & purificação , Infecções por Clostridium/veterinária , Contaminação de Alimentos/estatística & dados numéricos , Carne/microbiologia , Verduras/microbiologia , Matadouros/estatística & dados numéricos , Animais , Bovinos , Galinhas , Clostridioides difficile/classificação , Clostridioides difficile/genética , Clostridioides difficile/crescimento & desenvolvimento , Infecções por Clostridium/epidemiologia , Infecções por Clostridium/microbiologia , Qualidade de Produtos para o Consumidor , Fazendas/estatística & dados numéricos , Fezes/microbiologia , Contaminação de Alimentos/análise , Contaminação de Alimentos/economia , Humanos , Irlanda/epidemiologia , Carne/economia , Ovinos , Verduras/economia
20.
Food Microbiol ; 98: 103795, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33875223

RESUMO

Broiler meat is considered as the most important source of the foodborne pathogen Campylobacter jejuni. Exposure to stress conditions encountered during the slaughtering process may induce bacterial adaptation mechanisms, and enhance or decrease pathogen resistance to subsequent stress. This adaptation may result from changes in bacterial gene expression. This study aims to accurately quantify the expression of selected C. jejuni genes after stresses inspired from the poultry slaughtering process. RT-qPCR was used to quantify gene expression of 44 genes in three strains after successive heat and cold stresses. Main results indicated that 26 genes out of 44 were differentially expressed following the successive thermal stresses. Three clusters of genes were differentially expressed according to the strain and the stress condition. Up-regulated genes mainly included genes involved in the heat shock response, whereas down-regulated genes belonged to metabolic pathways (such as lipid, amino-acid metabolisms). However, four genes were similarly overexpressed in the three strains; they might represent indicators of the thermal stress response at the species scale. Advances in the molecular understanding of the stress response of pathogenic bacteria, such as Campylobacter, in real-life processing conditions will make it possible to identify technological levers and better mitigate the microbial risk.


Assuntos
Proteínas de Bactérias/genética , Infecções por Campylobacter/veterinária , Campylobacter jejuni/fisiologia , Galinhas/microbiologia , Matadouros , Animais , Proteínas de Bactérias/metabolismo , Infecções por Campylobacter/microbiologia , Campylobacter jejuni/genética , Campylobacter jejuni/metabolismo , Regulação Bacteriana da Expressão Gênica , Carne/microbiologia , Doenças das Aves Domésticas/microbiologia , Reação em Cadeia da Polimerase em Tempo Real , Estresse Fisiológico
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