Characterisation ofEscherichia coli isolated from raw milk cheeses

Zago, Miriam; Bonvini, Barbara; Platero, Antonio Manuel Martín; Mucchetti, G.; Carminati, Domenico; Giraffa, Giorgio

doi:10.1007/bf03175049

Cited by 13 publications

(8 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The absence of this pathogen in processed Minas Frescal cheese from creameries under IF is in accordance with the results obtained in Italy by Zago et al (2007), and strengthens the use of Good Manufacturing Practices and the application of specific normatives, such as IN 51-Ministry of Agriculture (2002), enhancing the importance of control procedures along the entire “farm-to-fork” chain.…”

Section: Discussionsupporting

confidence: 86%

PCR and ELISA (VIDAS ECO O157®) Escherichia coli O157:H7 identification in Minas Frescal cheese commercialized in Goiânia, GO

Carvalho¹,

Oliveira-Jr²,

Mesquita³

et al. 2014

Braz. J. Microbiol.

View full text Add to dashboard Cite

Escherichia coli O157:H7 has been incriminated in food poisoning outbreaks and sporadic cases of hemorrhagic colitis and hemolytic uremic syndrome in many countries. Considering the high susceptibility of Minas Frescal cheese to contamination by E. coli O157:H7, the aim of this study was to determine the occurrence of this pathogen through PCR (Polymerase Chain Reaction) and ELISA (VIDAS ECO O157®, bioMérieux, Lyon, France) test. Thirty cheese samples manufactured by artisan farmhouse producers were collected from open-air markets in Goiânia and thirty from industries under Federal Inspection located in Goiás State which trade their products in supermarkets in Goiânia. E. coli O157:H7 was detected in 6.67% samples collected in open air markets using ELISA, and 23,33% with PCR. The pathogen was not detected in samples from industries under Federal Inspection.

show abstract

Section: Discussionsupporting

confidence: 86%

PCR and ELISA (VIDAS ECO O157®) Escherichia coli O157:H7 identification in Minas Frescal cheese commercialized in Goiânia, GO

Carvalho¹,

Oliveira-Jr²,

Mesquita³

et al. 2014

Braz. J. Microbiol.

View full text Add to dashboard Cite

show abstract

“…Most of the non LAB genera identified in this study were also frequently detected in other artisanal dairy products. Whereas some authors suggested that they cause milk and cheese spoilage [38] , [47] , other publications indicate that they may have a secondary activity in the fermentation process of cheeses and can contribute to their taste and flavour [48] , [49] . M. caseolyticus and Hafnia alvei are known for their positive effects to the flavor development.…”

Section: Discussionmentioning

confidence: 99%

Dynamics of Bacterial Communities during the Ripening Process of Different Croatian Cheese Types Derived from Raw Ewe's Milk Cheeses

et al. 2013

View full text Add to dashboard Cite

Microbial communities play an important role in cheese ripening and determine the flavor and taste of different cheese types to a large extent. However, under adverse conditions human pathogens may colonize cheese samples during ripening and may thus cause severe outbreaks of diarrhoea and other diseases. Therefore in the present study we investigated the bacterial community structure of three raw ewe's milk cheese types, which are produced without the application of starter cultures during ripening from two production sites based on fingerprinting in combination with next generation sequencing of 16S rRNA gene amplicons. Overall a surprisingly high diversity was found in the analyzed samples and overall up to 213 OTU97 could be assigned. 20 of the major OTUs were present in all samples and include mostly lactic acid bacteria (LAB), mainly Lactococcus, and Enterococcus species. Abundance and diversity of these genera differed to a large extent between the 3 investigated cheese types and in response to the ripening process. Also a large number of non LAB genera could be identified based on phylogenetic alignments including mainly Enterobacteriaceae and Staphylococcacae. Some species belonging to these two families could be clearly assigned to species which are known as potential human pathogens like Staphylococcus saprophyticus or Salmonella spp. However, during cheese ripening their abundance was reduced. The bacterial genera, namely Lactobacillus, Streptococcus, Leuconostoc, Bifidobacterium, Brevibacterium, Corynebacterium, Clostridium, Staphylococcus, Thermoanerobacterium, E. coli, Hafnia, Pseudomonas, Janthinobacterium, Petrotoga, Kosmotoga, Megasphaera, Macrococcus, Mannheimia, Aerococcus, Vagococcus, Weissella and Pediococcus were identified at a relative low level and only in selected samples. Overall the microbial composition of the used milk and the management of the production units determined the bacterial community composition for all cheese types to a large extend, also at the late time points of cheese ripening.

show abstract

“…Raw milk cheeses, particularly soft and semihard cheeses, have been associated with pathogenic E. coli outbreaks (Altekruse et al, 1998). Conversely, high levels of non-pathogenic E. coli in raw milk cheeses may contribute to the development of desirable characteristics of some of these products (Zago et al, 2007). The main advantage of using phages as biocontrol agents against undesired bacteria in cheese is that the specificity of phage-host spare the microbiota responsible for infusing natural flavors from being killed during treatment (Pujato et al, 2018).…”

Section: Introductionmentioning

confidence: 99%

Diversity and Local Coadaptation of Escherichia coli and Coliphages From Small Ruminants

et al. 2020

View full text Add to dashboard Cite

Bacteriophages are highly specific predators that drive bacterial diversity through coevolution while striking tradeoffs among preserving host populations for long-term exploitation and increasing their virulence, structural stability, or host range. Escherichia coli and other coliform bacteria present in the microbiota of milk and during early ripening of raw milk cheeses have been linked to the production of gas, manifested by the appearance of eyes, and the development of off-flavors; thus, they might cause early blowing and cheese spoilage. Here, we report the characterization of coliphages isolated from manure from small ruminant farms and E. coli strains isolated from goat and sheep raw milk cheese. Additionally, the virulence and host range of locally isolated and laboratory collection phages were determined by comparing the susceptibility of E. coli strains from different sources. In agreement with the high genetic diversity found within the species E. coli, clustering analysis of whole-cell protein revealed a total of 13 distinct profiles but none of the raw milk cheese isolates showed inhibition of growth by reference or water-isolated coliphages. Conversely, 10 newly isolated phages had a broad host range (i.e., able to lyse ≥50% of bacterial hosts tested), thus exhibiting utility for biocontrol and only one cheese-isolated E. coli strain was resistant to all the phages. Whereas there was a high positive correlation between bacterial susceptibility range and lysis intensity, the phages virulence decreased as range increased until reaching a plateau. These results suggest local gene-for-gene coevolution between hosts and phages with selective tradeoffs for both resistance and competitive ability of the bacteria and host-range extension and virulence of the phage populations. Hence, different phage cocktail formulations might be required when devising long-term and short-term biocontrol strategies.

show abstract

Characterisation ofEscherichia coli isolated from raw milk cheeses

Cited by 13 publications

References 19 publications

PCR and ELISA (VIDAS ECO O157®) Escherichia coli O157:H7 identification in Minas Frescal cheese commercialized in Goiânia, GO

PCR and ELISA (VIDAS ECO O157®) Escherichia coli O157:H7 identification in Minas Frescal cheese commercialized in Goiânia, GO

Dynamics of Bacterial Communities during the Ripening Process of Different Croatian Cheese Types Derived from Raw Ewe's Milk Cheeses

Diversity and Local Coadaptation of Escherichia coli and Coliphages From Small Ruminants

Contact Info

Product

Resources

About