MIR spectroscopy as alternative method for further confirmation of foodborne pathogens Salmonella spp. and Listeria monocytogenes

The growth behaviour of foodborne pathogens (Staphylococcus aureus, Listeria monocytogenes, E. coli O157:H7 and Salmonella spp.) was investigated in pasteurised camel milk and compared with pasteurised bovine milk at different incubation temperatures. This study also aimed to compare the growth patterns of these four foodborne pathogens in pasteurised and raw camel milk. Pasteurised or raw camel milk and pasteurised bovine milk were separately inoculated with a cocktail of three strains of each foodborne pathogen. The inoculated milk samples were incubated at 10, 25, and 37°C. The total bacterial count (TBC) in raw milk and the total thermoduric bacteria count (TDB) in pasteurised milk samples were monitored. Greater growth inhibition rates of four pathogens were obtained for the pasteurised camel milk compared to the pasteurised bovine milk. Raw and pasteurised camel milk exerted bacteriostatic effect against all tested pathogens, particularly for the first 8 h of incubation in milk at the different temperatures. Pasteurised camel milk exerted an inhibitory activity that was equivalent to that of raw camel milk.

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Antimicrobial Resistance Profile of Salmonella and Listeria monocytogenes Isolated from Products Marketed on the Border of Brazil with Argentina and Uruguay

Journal of Food Protection ◽

10.4315/jfp-20-176 ◽

2020 ◽

Vol 83 (11) ◽

pp. 1941-1946

Author(s):

JULIANO GONÇALVES PEREIRA ◽

VANESSA MENDONÇA SOARES ◽

LEONARDO ERENO TADIELO ◽

TASSIANA RAMIRES ◽

WLADIMIR PADILHA da SILVA

Keyword(s):

Listeria Monocytogenes ◽

Antimicrobial Resistance ◽

Foodborne Pathogens ◽

Penicillin G ◽

Diffusion Method ◽

Salmonella Spp ◽

Disk Diffusion Method ◽

Resistance Profile ◽

Antimicrobial Resistance Profile ◽

Antimicrobial Resistance Genes

ABSTRACT We aimed to perform serotyping and the antimicrobial resistance profile of Salmonella spp. and Listeria monocytogenes strains isolated from raw meats imported illegally into Brazil along the borders of Argentina and Uruguay. Distinct isolates of Salmonella spp. (n = 6) and L. monocytogenes (n = 25) obtained from 270 of these food products of earlier work were serotyped and tested for antimicrobial resistance by agar disk diffusion method. For strains that were considered phenotypically resistant, antimicrobial resistance genes were investigated: strA, strB, floR, tetA, tetB, blaZ, blaTEM, ermB, ermC, and ereB to Salmonella sp. and blaZ and mecA to L. monocytogenes. All Salmonella isolates were identified as Salmonella Infantis; they were multidrug resistant and harbored the genes blaTEM (n = 6), strA (n = 1), strB (n = 1), floR (n = 1), ermB (n = 1), tetA (n = 3), and tetB (n = 3). L. monocytogenes isolates belonged to serovars 1/2a (n = 1), 1/2b (n = 14), 1/2c (n = 2), and 4b (n = 8), showed resistance only to penicillin G (n = 12), and did not show the blaZ and mecA genes. The results demonstrated that illegal foods that are commercialized in the Brazilian international border with Argentina and Uruguay may harbor foodborne pathogens, and some of them have multidrug resistance characteristics, such as Salmonella, emphasizing the need for greater control of international food transit in Brazil, especially in the region evaluated. HIGHLIGHTS

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Heat Resistance of Listeria monocytogenes

Journal of Food Protection ◽

10.4315/0362-028x-64.3.410 ◽

2001 ◽

Vol 64 (3) ◽

pp. 410-429 ◽

Cited By ~ 160

Author(s):

M. ELLIN DOYLE ◽

ALEJANDRO S. MAZZOTTA ◽

TIM WANG ◽

DANA W. WISEMAN ◽

VIRGINIA N. SCOTT

Keyword(s):

Listeria Monocytogenes ◽

Heat Resistance ◽

Foodborne Pathogens ◽

Fruits And Vegetables ◽

Culture Media ◽

Salt Content ◽

Growth Conditions ◽

Salmonella Spp ◽

Different Strains ◽

Resistance Data

The heat resistance data on Listeria monocytogenes in culture media and foods are summarized. Most heat resistance data for foods have been obtained in dairy, meat, poultry, and egg products. Limited data have been published on seafood, fruits, and vegetables. The methodologies employed have evolved over time; hence data from earlier experiments are not directly comparable to more recent studies. Many factors influence the heat resistance of L. monocytogenes. Variation exists among different strains in their ability to withstand heat treatment. In addition, heat resistance is influenced by age of the culture, growth conditions, recovery media, and characteristics of foods such as salt content, aw, acidity, and the presence of other inhibitors. Listeriae are more heat resistant than most other nonspore-forming foodborne pathogens, and thus, processing recommendations based on data from experiments with Salmonella spp. or pathogenic Escherichia coli may not be sufficient to eliminate similar numbers of L. monocytogenes. The data provided in this review may prove useful for food processors in determining appropriate times and temperatures for producing foods free of vegetative pathogens.

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Molecular characterization of Salmonella spp. and Listeria monocytogenes strains from biofilms in cattle and poultry slaughterhouses located in the federal District and State of Goiás, Brazil

PLoS ONE ◽

10.1371/journal.pone.0259687 ◽

2021 ◽

Vol 16 (11) ◽

pp. e0259687

Author(s):

Emilia Fernanda Agostinho Davanzo ◽

Rebecca Lavarini dos Santos ◽

Virgilio Hipólito de Lemos Castro ◽

Joana Marchesini Palma ◽

Bruno Rocha Pribul ◽

...

Keyword(s):

Listeria Monocytogenes ◽

Molecular Characterization ◽

Foodborne Pathogens ◽

Federal District ◽

Multidrug Resistant ◽

Animal Origin ◽

Meat Production ◽

Salmonella Spp

Listeria monocytogenes and Salmonella spp. are considered important foodborne pathogens that are commonly associated with foods of animal origin. The aim of this study was to perform molecular characterization of L. monocytogenes and Salmonella spp. isolated from biofilms of cattle and poultry slaughterhouses located in the Federal District and State of Goiás, Brazil. Fourteen L. monocytogenes isolates and one Salmonella sp. were detected in poultry slaughterhouses. No isolates were detected in cattle slaughterhouses. All L. monocytogenes isolates belonged to lineage II, and 11 different pulsotypes were detected. Pulsed-field gel electrophoresis analysis revealed the dissemination of two strains within one plant, in addition to the regional dissemination of one of them. The Salmonella isolate was identified via whole genome sequencing as Salmonella enterica serovar Minnesota ST548. In the sequence analysis, no premature stop codons were detected in the inlA gene of Listeria. All isolates demonstrated the ability to adhere to Caco-2 cells, while 50% were capable of invading them. Antimicrobial resistance was detected in 57.1% of the L. monocytogenes isolates, and resistance to sulfonamide was the most common feature. The tetC, ermB, and tetM genes were detected, and four isolates were classified as multidrug-resistant. Salmonella sp. was resistant to nine antimicrobials and was classified as multidrug-resistant. Resistance genes qnrB19, blaCMY-2, aac(6’)-Iaa, sul2, and tetA, and a mutation in the parC gene were detected. The majority (78.5%) of the L. monocytogenes isolates were capable of forming biofilms after incubation at 37°C for 24 h, and 64.3% were capable of forming biofilms after incubation at 12°C for 168 h. There was no statistical difference in the biofilm-forming capacity under the different evaluated conditions. Salmonella sp. was capable of forming biofilms at both tested temperatures. Biofilm characterization was confirmed by collecting the samples consistently, at the same sampling points, and by assessing biofilm formation in vitro. These results highlight the potential risk of cross-contamination in poultry slaughterhouses and the importance of surveillance and pathogen control maintenance programs within the meat production industry.

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Molecular characterization of foodborne pathogenic bacteria recovered from fermented meat products

10.33888/jms.2021.321 ◽

2021 ◽

Vol 3 (2) ◽

pp. 1-10

Author(s):

Naeima M. H. Yousef ◽

Doaa M. Abd El- Aziz ◽

Martina A. Mansour

Keyword(s):

Listeria Monocytogenes ◽

Foodborne Pathogens ◽

Pathogenic Bacteria ◽

Meat Products ◽

Salmonella Spp ◽

E Coli ◽

Two Samples ◽

Control And Prevention ◽

Foodborne Pathogenic Bacteria ◽

Meat Samples

Foodborne pathogenic bacteria are causing diseases with a significant effect on human health and the economy. The four most common bacterial foodborne pathogens were isolated from different fermented meat products and characterized molecularly in the current study. A total of 20 random samples of fermented meat products, including Hotdog, pepperoni, salami, sausage, and luncheon (4 from each), were collected from different markets to be examined bacteriologically for detection of foodborne pathogenic bacteria. The samples were tested by culture for the presence of bacteria. PCR was used as a diagnostic tool for the proper identification of foodborne pathogenic bacteria. So, the pure isolates were identified and confirmed by PCR- based method using specific primers for each genus. The isolated pathogenic bacteria were identified as Escherichia coli 0157:H7, Listeria monocytogenes, Salmonella sp. and Staphylococcus aureus. Out of 20 samples, only one sample contains E. coli 0157:H7. Listeria monocytogenes and Salmonella spp. were isolated from two samples. At the same time, S. aureus was found in 6 samples, one of which was mecA positive. The results revealed the presence of foodborne pathogenic bacteria in fermented meat samples. So, to decrease the human hazard risk and a major public health threat associated with foodborne pathogenic bacteria and their toxins, a greater emphasis should be applied in control and prevention of contamination during processing and manipulation.

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Prevalence of Salmonella spp. and Listeria monocytogenes at Small-Scale Spanish Factories Producing Traditional Fermented Sausages

Journal of Food Protection ◽

10.4315/0362-028x.jfp-10-437 ◽

2011 ◽

Vol 74 (5) ◽

pp. 812-815 ◽

Cited By ~ 20

Author(s):

BELEN MARTIN ◽

MARGARITA GARRIGA ◽

TERESA AYMERICH

Keyword(s):

Listeria Monocytogenes ◽

Foodborne Pathogens ◽

Manufacturing Process ◽

Raw Materials ◽

Geographic Location ◽

Small Scale ◽

Salmonella Spp ◽

Fermented Sausage ◽

Fermented Sausages ◽

Microbiological Techniques

The manufacturing of fermented sausages is subject to natural contamination processes that can potentially carry foodborne pathogens along the process chain and result in contamination of the final product. The aim of this study was to evaluate the occurrence of Salmonella spp. and Listeria monocytogenes at different sampling points during the manufacturing process of fuet, a type of traditional fermented sausage, at 10 small-scale Spanish factories. The presence of both pathogens was studied in the raw materials (19 casings and 19 meat batters), the final products (19 fermented sausages), and the factory equipment (12 mincing, 12 mixing, and 19 stuffing machines, 19 cutting tables, 11 knives, and 12 cold rooms) by using classical microbiological techniques and real-time PCR. Salmonella was not detected in the equipment analyzed or in the final products, but it was detected in the raw materials (23.7% of samples). L. monocytogenes showed higher incidence than Salmonella and was detected in the equipment (11.8% of samples), the raw materials (28.9%), and the final products (15.8%), confirming its ubiquity throughout the manufacturing process of fermented sausages. Five factories were further investigated to study the changes in the distribution of pathogens in the fuet production process over a period of either 2 or 3 years. There was considerable variation in the incidence of both pathogens at different sampling periods, and there was no relation between seasonal variations or geographic location of the factories.

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Caracterización de la leche y queso artesanal de la región de Ojos Negros Baja California, México.

Revista Mexicana de Ciencias Pecuarias ◽

10.22319/rmcp.v11i2.5084 ◽

2020 ◽

Vol 11 (2) ◽

pp. 553-564

Author(s):

Laura E. Silva-Paz ◽

Gerardo E. Medina-Basulto ◽

Gilberto López-Valencia ◽

Martin F. Montaño-Gómez ◽

Rafael Villa-Angulo ◽

...

Keyword(s):

Listeria Monocytogenes ◽

Baja California ◽

Salmonella Spp ◽

Buenas Prácticas

La comunidad de Ojos Negros está ubicada en el municipio de Ensenada Baja California, México. Desde 1930, los residentes locales fabrican un queso artesanal muy apreciado en la región; sin embargo, la leche cruda y el queso nunca han sido analizados por la calidad microbiológica y de higiene del producto final. El objetivo del presente estudio fue evaluar la calidad microbiológica, física y química de la leche cruda utilizada para producir queso y el queso artesanal producido en las 22 unidades de producción individuales. Se tomaron muestras de queso y leche de las unidades de producción para realizar pruebas microbiológicas. Se realizaron determinaciones físicas y químicas de proteínas, grasas y lactosa utilizando un analizador LACTOSCAN-S. Los resultados del análisis de la leche mostraron un contenido de proteína (33,11 g/l) y grasa (39,89 g/l) dentro de los parámetros de la normatividad. Para la calidad microbiológica de la leche, los resultados del recuento de mesófilos aeróbicos mostraron un cumplimiento del 64% con las regulaciones; sin embargo, el mismo conteo de mesófilos aeróbicos en las muestras de queso resultó en solo el 4% de cumplimiento con las regulaciones. No hubo detección de Salmonella spp. o Listeria monocytogenes en cualquiera de las muestras de leche o de queso probadas. Se deben incorporar buenas prácticas sanitarias y de fabricación para mejorar la calidad sanitaria y de higiene para la producción de queso artesanal en la comunidad de Ojos Negros.

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The Use of Bacteriophages in the Poultry Industry

Animals ◽

10.3390/ani10050872 ◽

2020 ◽

Vol 10 (5) ◽

pp. 872 ◽

Cited By ~ 6

Author(s):

Katarzyna Żbikowska ◽

Monika Michalczuk ◽

Beata Dolka

Keyword(s):

Foodborne Pathogens ◽

Pathogenic Bacteria ◽

Bacterial Resistance ◽

Health And Safety ◽

Legal Framework ◽

Multidrug Resistant ◽

Poultry Production ◽

Salmonella Spp ◽

Food Contact Surfaces ◽

Public Health And Safety

The emergence of multidrug-resistant infections and antibiotic failures have raised concerns over human and veterinary medicine worldwide. Poultry production has had to confront the problems of an alarming increase in bacterial resistance, including zoonotic pathogens. According to the European Food Safety Authority (EFSA), campylobacteriosis and salmonellosis have been the most frequently reported human foodborne diseases linked to poultry. This situation has strongly stimulated a renewal of scientists’ interest in bacteriophages (phages) since the beginning of the 21st century. Bacteriophages are the viruses of bacteria. They are abundant in nature, and accompany bacteria in each environment they colonize, including human microbiota. In this review, we focused on the use of bacteriophages as therapeutic agents to treat infections and reduce counts of pathogenic bacteria in poultry, as biocontrol agents to eliminate foodborne pathogens on/in food, and also as disinfectants to reduce contamination on food-contact surfaces or poultry carcasses in industrial conditions. Most of the phage-based products are targeted against the main foodborne pathogens, such as Campylobacter jejuni, Salmonella spp., Escherichia coli, Listeria monocytogenes, Staphylococcus aureus, and Clostridium perfringens. Phages are currently addressed at all stages of the poultry production "from farm to fork", however, their implementation into live birds and food products still provokes discussions especially in the context of the current legal framework, limitations, as well as public health and safety.

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Insects as vectors of foodborne pathogenic bacteria

Terrestrial Arthropod Reviews ◽

10.1163/187498311x543989 ◽

2011 ◽

Vol 4 (1) ◽

pp. 5-16 ◽

Cited By ~ 21

Author(s):

Jeffrey Blazar ◽

Marc Allard ◽

E. Kurt Lienau

Keyword(s):

Food Safety ◽

Foodborne Pathogens ◽

Pathogenic Bacteria ◽

Current Knowledge ◽

Disease Outbreaks ◽

House Fly ◽

American Cockroach ◽

Health Concern ◽

Foodborne Disease ◽

Salmonella Spp

AbstractFood safety is an important consideration worldwide. To maintain and improve our current knowledge of foodborne disease outbreaks, we must understand some of the more imminent issues related to food safety. A variety of agents are responsible for transmitting the estimated 76 million cases of illnesses caused by foodborne pathogens every year. This review explores why insects pose a serious health concern, in terms of worldwide food safety initiatives, by looking at evidence in published <abs>Food safety is an important consideration worldwide. To maintain and improve our current knowledge of foodborne disease outbreaks, we must understand some of the more imminent issues related to food safety. A variety of agents are responsible for transmitting the estimated 76 million cases of illnesses caused by foodborne pathogens every year. This review explores why insects pose a serious health concern, in terms of worldwide food safety initiatives, by looking at evidence in published literature. We highlight at least eleven different species of insects, including the lesser mealworm, Alphitobius diaperinus (Panzer); secondary screwworm, Cochliomyia macellaria (Fabricius); synanthropic flies [flesh fly, Sarcophaga carnaria (L.); house fly, Musca domestica (L.); fruit fly, Drosophila melanogaster (Meigen); and stable fly, Stomoxys calcitrans (L.)], American cockroach, Periplaneta americana (L.); German cockroach, Blatella germanica (L.); Oriental cockroach, Blatta orientalis (L.); Pacific beetle cockroach, Diploptera punctata (Eschscholtz); and Speckled feeder cockroach, Nauphoeta cinerea (Olivier), which act as vectors for Salmonella spp. or Escherichia coli and illustrate how these insects are successful vectors of foodborne disease outbreaks. We propose that insects be considered as one of the latest issues in food safety initiatives. Not only are some insects extremely important contributors to diseases, but now we suggest that more research into insects as potential carriers of E. coli and Salmonella spp., and therefore as contributing to foodborne disease outbreaks, is granted.

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