Survival of Listeria monocytogenes and Enterococcus faecium in sludge evaluated by real-time PCR and culture methods

Wéry, Nathalie; Pourcher, Anne‐Marie; Stan, V.; Delgenès, Jean-Philippe; Picard-Bonnaud, F.; Godon, Jean‐Jacques

doi:10.1111/j.1472-765x.2006.01946.x

Cited by 23 publications

(16 citation statements)

References 28 publications

(53 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This result is in agreement with Pedersen and Jacobsen (54), who found a significant difference between the CFU and DNA levels when investigating the survival of microorganisms in an air-dried soil. It is possible that some of this DNA actually derived from dead cells in manure and soil, but it has been argued that the half-life of DNA in environmental samples is very short because of the presence of nucleases (55,56,57).…”

Section: Resultsmentioning

confidence: 99%

Persistence and Leaching Potential of Microorganisms and Mineral N in Animal Manure Applied to Intact Soil Columns

Amin

Forslund

Bui

et al. 2013

Appl Environ Microbiol

View full text Add to dashboard Cite

Pathogens may reach agricultural soils through application of animal manure and thereby pose a risk of contaminating crops as well as surface and groundwater. Treatment and handling of manure for improved nutrient and odor management may also influence the amount and fate of manure-borne pathogens in the soil. A study was conducted to investigate the leaching potentials of a phage (Salmonella enterica serovar Typhimurium bacteriophage 28B) and two bacteria, Escherichia coli and Enterococcus species, in a liquid fraction of raw pig slurry obtained by solid-liquid separation of this slurry and in this liquid fraction after ozonation, when applied to intact soil columns by subsurface injection. We also compared leaching potentials of surface-applied and subsurface-injected raw slurry. The columns were exposed to irrigation events (3.5-h period at 10 mm h ؊1 ) after 1, 2, 3, and 4 weeks of incubation with collection of leachate. By the end of incubation, the distribution and survival of microorganisms in the soil of each treatment and in nonirrigated columns with injected raw slurry or liquid fraction were determined. E. coli in the leachates was quantified by both plate counts and quantitative PCR (qPCR) to assess the proportions of culturable and nonculturable (viable and nonviable) cells. Solid-liquid separation of slurry increased the redistribution in soil of contaminants in the liquid fraction compared to raw slurry, and the percent recovery of E. coli and Enterococcus species was higher for the liquid fraction than for raw slurry after the four leaching events. The liquid fraction also resulted in more leaching of all contaminants except Enterococcus species than did raw slurry. Ozonation reduced E. coli leaching only. Injection enhanced the leaching potential of the microorganisms investigated compared to surface application, probably because of a better survival with subsurface injection and a shorter leaching path.

show abstract

Section: Resultsmentioning

confidence: 99%

Persistence and Leaching Potential of Microorganisms and Mineral N in Animal Manure Applied to Intact Soil Columns

Amin

Forslund

Bui

et al. 2013

Appl Environ Microbiol

View full text Add to dashboard Cite

show abstract

“…Even though it has been argued that the half-life of DNA in environmental samples may be very short because of the presence of nucleases (32,53), also very old DNA has been shown to persist in soil (33). Levels of Salmonella serovar Typhimurium based on DNA quantifications were significantly higher than those obtained by plate counting, especially in manure-amended samples at low temperatures.…”

Section: Discussionmentioning

confidence: 99%

Influence of Temperature and Predation on Survival of Salmonella enterica Serovar Typhimurium and Expression of invA in Soil and Manure-Amended Soil

Bælum

Fredslund

et al. 2010

Appl Environ Microbiol

View full text Add to dashboard Cite

The effects of three temperatures (5, 15, and 25°C) on the survival of Salmonella enterica serovar Typhimurium in topsoil were investigated in small microcosms by three different techniques: plate counting, invA gene quantification, and invA mRNA quantification. Differences in survival were related to the effect of protozoan predation. Tetracycline-resistant Salmonella serovar Typhimurium was inoculated into soil and manure-amended soil at 1.5 ؋ 10 8 cells g soil ؊1 . Population densities were determined by plate counting and by molecular methods and monitored for 42 days. Simultaneous extraction of RNA and DNA, followed by quantitative PCR, was used to investigate invA gene levels and expression. Analysis by these three techniques showed that Salmonella serovar Typhimurium survived better at 5°C. Comparing DNA and CFU levels, significantly higher values were determined by DNA-based techniques. invA mRNA levels showed a fast decrease in activity, with no detectable mRNA after an incubation period of less than 4 days in any of the soil scenarios. A negative correlation was found between Salmonella serovar Typhimurium CFU levels and protozoan most probable numbers, and we propose the role of the predator-prey interaction as a factor to explain the die-off of the introduced strain by both culture-and DNA quantification-based methods. The results indicate that temperature, manure, and protozoan predation are important factors influencing the survival of Salmonella serovar Typhimurium in soil.

show abstract

“…Pathogens or indicators in such a state lose their ability to grow in/ on culture media, but may retain their infectivity. Therefore, this dormancy state can result in an underestimation of infectious pathogen numbers (Garrec et al, 2003;Lebuhn et al, 2004;Wery et al, 2006), increasing the uncertainty of data obtained via culture methods in QMRA (Haas et al, 1999).…”

Section: Introductionmentioning

confidence: 99%

Inactivation of indicators and pathogens in cattle feedlot manures and compost as determined by molecular and culture assays

Klein

Brown

Ashbolt

et al. 2011

FEMS Microbiology Ecology

View full text Add to dashboard Cite

Accurate and conservative information about pathogen inactivation rates is needed as the basis for safe manure management on beef cattle feedlots. The survival of indicators and pathogens in faecal pen manure, stockpiled manure and manure compost was measured with autochthonous indicator bacteria (Escherichia coli, Clostridium perfringens, enterococci, total coliforms) and pathogens (Listeria monocytogenes, Campylobacter jejuni) using culture and/or real-time quantitative PCR (qPCR) methods. Additionally, the manures were incubated at 20, 37, 50 and 60 °C in microcosms to quantify the persistence of autochthonous microorganisms and selected process performance surrogates (Clostridium sporogenes, green fluorescent protein-labelled E. coli and L. monocytogenes). Estimated qPCR cell counts indicated that up to four orders of magnitude more target cells were present compared with the culturable counts. Corresponding T(90) estimates were up to sixfold higher. This study demonstrates the benefits of nucleic acid-based quantification of pathogen inactivation in cattle manures and concludes that the concurrent analysis of microorganisms by molecular and culture methods provides complementary value.

show abstract

Survival of Listeria monocytogenes and Enterococcus faecium in sludge evaluated by real-time PCR and culture methods

Cited by 23 publications

References 28 publications

Persistence and Leaching Potential of Microorganisms and Mineral N in Animal Manure Applied to Intact Soil Columns

Persistence and Leaching Potential of Microorganisms and Mineral N in Animal Manure Applied to Intact Soil Columns

Influence of Temperature and Predation on Survival of Salmonella enterica Serovar Typhimurium and Expression of invA in Soil and Manure-Amended Soil

Inactivation of indicators and pathogens in cattle feedlot manures and compost as determined by molecular and culture assays

Contact Info

Product

Resources

About