Aerosolisation of Escherichia coli and associated endotoxin using an improved bubbling bioaerosol generator

Simon, Xavier; Duquenne, Philippe; Koehler, Véronique; Piernot, C.; Coulais, Catherine; Faure, Marie

doi:10.1016/j.jaerosci.2011.05.002

Cited by 38 publications

(47 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…5(a)), respectively. This difference between the optical and aerodynamic diameters was previously reported for airborne microorganisms (Terzieva et al, 1996;Simon et al, 2011) and may be due to differences between the measurement methods. The values reported here differ somewhat from previous results, but this could be explained by differences between generation methods, measuring instruments, operating conditions (e.g.…”

Section: Nature Of the Particles Generatedmentioning

confidence: 46%

See 1 more Smart Citation

Feasibility of Generating Peaks of Bioaerosols for Laboratory Experiments

Simon

Duquenne

2013

Aerosol Air Qual. Res.

Self Cite

View full text Add to dashboard Cite

Bioaerosol concentration peaks are frequently encountered in real-life atmospheres (indoor, outdoor, workplace, etc.), where they can be caused by several factors. However, evolution over time and variability of microbiological pollutant concentrations remain under-documented. The contribution of such peaks in the onset or the worsening of respiratory symptoms -in particular immuno-allergic reactions -has yet to be extensively studied. Although experimental bioaerosol generators are increasingly used, the intentional and controlled production of concentration peaks of biological agents has not yet been utilized in laboratory experiments. The main objective of this study was to show that it is possible to produce experimental bioaerosol concentration peaks with defined characteristics. Experiments were performed with a 'Liquid Sparging Aerosoliser'-type generator. With this system, peaks can be created by increasing the bubbling airflow through a film of bacterial (Escherichia coli) or fungal (Penicillium brevicompactum) liquid culture. The higher the set point value of the bubbling airflow, the greater the maximum bioaerosol concentration during the generated peak. Similarly, longer-lived peaks can be created by maintaining the increased airflow for a longer period of time. For both studied species, the relative size distribution was constant over time, regardless of modifications to the bubbling flow rate. The operator can monitor and control peak formation with this system thanks to real-time measurement of the number concentrations, targeting the appropriate particle size classes corresponding to diameters of the aerosolised microorganisms. This generator, characterized by gentle aerosolisation and a capacity to produce bioaerosol peaks, may contribute to enrich laboratory experiments for numerous applications.

show abstract

Section: Nature Of the Particles Generatedmentioning

confidence: 46%

“…1). This setup and all the materials used have been previously described (Simon et al, 2011. Briefly, a peristaltic pump feeds the liquid culture onto the upper surface of a 2-mm thick stainless steel porous disc (Stemm, 30 mm in diameter, 1 μm pore diameter), which settles as a liquid film.…”

Section: Description Of the Setup For Bioaerosol Generation And Charamentioning

confidence: 99%

Feasibility of Generating Peaks of Bioaerosols for Laboratory Experiments

Simon

Duquenne

2013

Aerosol Air Qual. Res.

Self Cite

View full text Add to dashboard Cite

show abstract

“…In preparation for the test, a pathogen/soil mixture (200 CFU g −1 ) was serially diluted until fractional values (depicted by the negative log) were obtained in order to test the qPCR response over a broad range of values that extend into the barely detectable range. Regression coefficients: S. enterica=0.31, p>0.05, P. aeruginosa=0.89, p<0.05 recovery rates and LOD of aerosolized bacteria, all reporting low recoveries (Ryan et al 2014;Simon et al 2011), often four to five orders of magnitude lower than spiking concentrations, and high LOD (Landman et al 2013;Ryan et al 2014). Here, we spiked an aerosol generator with relatively low concentrations of the tested cells ranging from 10 3 to 10 5 CFU mL −1 and could not detect P. aeruginosa in the collected air via the standard culture-dependent methods (plating onto selective agar) but only via the MPN-qPCR method after enrichment (Fig.…”

Section: Discussionmentioning

confidence: 99%

Rapid MPN-Qpcr Screening for Pathogens in Air, Soil, Water, and Agricultural Produce

Orlofsky

Benami

Gross

et al. 2015

Water Air Soil Pollut

View full text Add to dashboard Cite

A sensitive, high-throughput, and costeffective method for screening bacterial pathogens in the environment was developed. A variety of environmental samples, including aerosols, soil of various types (sand, sand/clay mix, and clay), wastewater, and vegetable surface (modeled by tomato), were concomitantly spiked with Salmonella enterica and/or Pseudomonas aeruginosa to determine recovery rates and limits of detection. The various matrices were first enriched with a general pre-enrichment broth in a dilution series and then enumerated by most probable number (MPN) estimation using quantitative PCR for rapid screening of amplicon presence. Soil and aerosols were then tested in non-spiked environmental samples, as these matrices are prone to large experimental variation. Limit of detection in the various soil types was 1-3 colony-forming units (CFU) g −1 ; on vegetable surface, 5 CFU per tomato; in treated wastewater, 5 CFU L −1 ; and in aerosols, >300 CFU mL −1 . Our method accurately identified S. enterica in non-spiked environmental soil samples within a day, while traditional methods took 4 to 5 days and required sorting through biochemically and morphologically similar species. Likewise, our method successfully identified P. aeruginosa in non-spiked aerosols generated by a domestic wastewater treatment system. The obtained results suggest that the developed method presents a broad approach for the rapid, efficient, and reliable detection of relatively low densities of pathogenic organisms in challenging environmental samples.

show abstract

“…As shown in Figure 2c, this setup included a "Liquid Sparging Aerosolizer"-type bubbling generator and a 12-L homogenization vessel equipped with six sampling probes that have been described elsewhere (Simon et al 2011;Simon and Duquenne 2013). The test aerosol consisted of a model microorganism, E. coli (Institut Pasteur CIP 53.126).…”

Section: Test Rig For Bioaerosol Generation (Protocol D)mentioning

confidence: 99%

“…The test aerosol consisted of a model microorganism, E. coli (Institut Pasteur CIP 53.126). Liquid cultures of vegetative cells were prepared as described in Simon et al (2011). A peristaltic pump fed the liquid culture onto the upper surface of a porous stainless steel disk.…”

Section: Test Rig For Bioaerosol Generation (Protocol D)mentioning

confidence: 99%

Physical performances and kinetics of evaporation of the CIP 10-M personal sampler's rotating cup containing aqueous or viscous collection fluid

Simon

Bau

Boivin

et al. 2016

Aerosol Science and Technology

Self Cite

View full text Add to dashboard Cite

The CIP 10-M personal sampler measures worker exposure to airborne particles by collecting particles in a rotating metal cup containing a few milliliters of a collection fluid. This device is mainly used to sample microorganisms or microbial components to measure bioaerosol concentrations in various occupational environments. Aqueous liquids are generally used, but their rapid evaporation limits the duration of sampling; alternative collection fluids could alleviate this problem. Indeed, the particle-collection efficiency of the rotating cup has not been extensively studied, and the only data available relate to a discontinued model. This study aimed to measure the collection efficiency of the current rotating cup model containing an aqueous (water) or viscous (ViaTrap mineral oil) collection fluid. The kinetics of evaporation confirmed that ViaTrap does not evaporate, making 8-h sampling campaigns in constant volumes feasible. Particles with a wide range of aerodynamic diameters (between around 0.1 and 10 mm) were produced using various test rigs and mono-or polydisperse test aerosols. Both new and older cup models performed similarly, with a collection efficiency of >80% for larger particles (aerodynamic diameters >2.8 mm), progressively decreasing to around 50% for aerodynamic diameters of 2.1 mm; with aerodynamic diameters of <1 mm, the collection efficiency was generally <10%. In physical terms, collection efficiency was unaffected by the type (aqueous or viscous) or volume (between 0 and 3 mL) of collection fluid used. Bias maps indicated that the inhalable fraction may be underestimated in occupational settings, particularly with aerosols mainly composed of particles with aerodynamic diameters of less than around 3 mm. EDITORTiina Reponen

show abstract

Aerosolisation of Escherichia coli and associated endotoxin using an improved bubbling bioaerosol generator

Cited by 38 publications

References 41 publications

Feasibility of Generating Peaks of Bioaerosols for Laboratory Experiments

Feasibility of Generating Peaks of Bioaerosols for Laboratory Experiments

Rapid MPN-Qpcr Screening for Pathogens in Air, Soil, Water, and Agricultural Produce

Physical performances and kinetics of evaporation of the CIP 10-M personal sampler's rotating cup containing aqueous or viscous collection fluid

Contact Info

Product

Resources

About