Influence of incubation conditions on the formation of model biofilms by<i>Listeria monocytogenes</i>and<i>Salmonella</i>Typhimurium on abiotic surfaces

Govaert, Marlies; Smet, Cindy; Baka, Maria; Janssens, Tom; Impe, Jan Van

doi:10.1111/jam.14071

Cited by 32 publications

(48 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For the development of the biofilm cell type, the protocol and optimal incubation conditions of Govaert et al (2018a) were used to obtain strongly adherent and mature biofilms. Biofilms were grown on polystyrene Petri dishes, representing hydrophobic surfaces relevant for the food industry (cutting surfaces made of polymeric material, packaging materials, conveyor belts, tanks, pipework, etc.).…”

Section: Methodsmentioning

confidence: 99%

“…After 5, 10, 25, or 30 min of PAL treatment, the PAL was removed, and the biofilms were rinsed 3 times with sterile PBS solution in order to remove all remaining active species. After this, biofilms were again allowed to dry and the cell scraping method as described in Govaert et al (2018a) was used to remove the biofilms from the surface. Finally, serial decimal dilutions were made from the obtained cell suspensions and plated on both general and selective medium.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Inactivation of Single Strains of Listeria monocytogenes and Salmonella Typhimurium Planktonic Cells Biofilms With Plasma Activated Liquids

et al. 2019

View full text Add to dashboard Cite

Recent research has proven the ability of cold atmospheric plasma (CAP) for assuring food safety. A more flexible and transportable alternative is the use of plasma activated liquids (PAL), which are also known to have antimicrobial properties. However, within the context of food safety, little is known on its potential regarding decontamination. This research therefore focusses on identifying the impact of (i) the microbial species and its cell type (planktonic cells or biofilms), (ii) the CAP settings (i.e., gas composition and generation time) and (iii) PAL related factors (treatment time and PAL age) on the technologies efficacy. Cell densities were monitored using the plate counting technique for which the results were analyzed by means of predictive inactivation models. Moreover, the pH and the concentrations of long-lived species (i.e., hydrogen peroxide, nitrite, and nitrate) were measured to characterize the PAL solutions. The results indicated that although the type of pathogen impacted the efficacy of the treatment, mainly the cell mode had an important effect. The presence of oxygen in the operating gas ensured the generation of PAL solutions with a higher antimicrobial activity. Moreover, to ensure a good microbial inactivation, PAL generation times needed to be sufficiently long. Both CAP related factors resulted in a higher amount of long-lived species, enhancing the inactivation. For 30 min. PAL generation using O 2 , this resulted in log reductions up to 3.9 for biofilms or 5.8 for planktonic cells. However, loss of the PAL activity for stored solutions, together with the frequent appearance of a tailing phase in the inactivation kinetics, hinted at the importance of the short-lived species generated. Different factors, related to (i) the pathogen and its cell mode, (ii) the CAP settings and (iii) PAL related factors, proved to impact the antimicrobial efficacy of the solutions and should be considered with respect to future applications of the PAL technology.

show abstract

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Inactivation of Single Strains of Listeria monocytogenes and Salmonella Typhimurium Planktonic Cells Biofilms With Plasma Activated Liquids

et al. 2019

View full text Add to dashboard Cite

show abstract

“…Typhimurium) were 1:1, 1:2, 2:1, 1:3, and 3:1 and the selected dilution/growth media were BHI and 20-fold-diluted TSB (TSB/20), which proved to be the optimal media for single-species biofilm development by L. monocytogenes and S . Typhimurium, respectively (Govaert et al, 2018b).…”

Section: Methodsmentioning

confidence: 99%

“…Dependent on the applied (incubation) conditions, Petri dishes were incubated for 0–24 h at 25 or 30°C, which were the optimal temperatures for S . Typhimurium and L. monocytogenes single-species biofilm formation, respectively (Govaert et al, 2018b).…”

Section: Methodsmentioning

confidence: 99%

Dual-Species Model Biofilm Consisting of Listeria monocytogenes and Salmonella Typhimurium: Development and Inactivation With Cold Atmospheric Plasma (CAP)

et al. 2019

View full text Add to dashboard Cite

Most environmental biofilms contain a variety of species. These species can establish cooperative and competitive interactions, possibly resulting in an increase or a decrease in antimicrobial resistance. Therefore, results obtained following inactivation of single-species biofilms by means of different technologies (e.g., Cold Atmospheric Plasma, CAP) should be validated for multi-species biofilms. First, a strongly adherent and mature Listeria monocytogenes and S. Typhimurium dual-species biofilm was developed by altering different incubation conditions, i.e., growth medium, incubation temperature, inoculum ratio of L. monocytogenes and S. Typhimurium cells, and incubation time. Adherence and maturity were quantified by means of optical density measurements and viable plate counts, respectively. Secondly, both the (1 day old) reference biofilm and a more mature 7 days old biofilm were treated for different CAP treatment times (0–30 min). Viable plate counts were again used to determine the (remaining) cell density. For both the biofilm development and inactivation, predictive models were applied to describe the growth/inactivation kinetics. Finally, the kinetics of the [1 and 7 day(s) old] dual-species biofilms were compared with those obtained for the corresponding single-species biofilms. Results implied that a strongly adherent and mature reference dual-species biofilm was obtained following 24 h of incubation at 25°C using 20-fold diluted TSB and an inoculum ratio of 1:1. Main observations regarding CAP inactivation were: (i) the dual-species biofilm age had no influence on the CAP efficacy, although a longer treatment time was required for the oldest biofilm, (ii) for the 1 day old biofilms, CAP treatment became less efficient for S. Typhimurium inactivation when this species was part of the dual-species biofilm, while L. monocytogenes inactivation was not influenced by the biofilm type, and (iii) for the 7 days old biofilms, CAP inactivation of both species became more efficient when they were part of the dual-species biofilms. It can be concluded that the efficacy of the CAP treatment is altered when cells become part of a dual-species biofilm, which is quite important with respect to a possible application of CAP for biofilm inactivation within the food industry.

show abstract

“…; Govaert et al . ). The refrigerated conditions found in the preservation, processing and storage of aquatic products are often disregarded when developing target biofilm of spoilage bacteria.…”

Section: Introductionmentioning

confidence: 97%

Competitive interaction on dual‐species biofilm formation by spoilage bacteria, Shewanella baltica and Pseudomonas fluorescens

et al. 2019

View full text Add to dashboard Cite

Aims: This study aims to characterize the biofilm produced by mono-and dual-species of Shewanella baltica and Pseudomonas fluorescens as fish spoilers at the different incubation temperature, and to elucidate the interactive behaviour of dual-species biofilm development. Methods and Results: The mono-and dual-species biofilm formation and adhesion characteristics of S. baltica and P. fluorescens were evaluated by using crystal violet staining, scanning electron microscopy and confocal laser scanning microscopy. Results showed that P. fluorescens had significantly higher biofilm biomass and polysaccharides production than S. baltica, and two isolates reached the maximum biofilm biomass during the early stationary phase. Lower biomass and polysaccharides in dual-species biofilms were observed compared to mono-species of P. fluorescens. Meanwhile, S. baltica and P. fluorescens formed fragile and viscous pellicles with different spatial architectures respectively. In dual-species pellicle few large microcolonies were dominated by P. fluorescens. Compared to mono-species of PF07, adherent cell population and biofilm thickness at the developing phase significantly decreased, and biofilm-forming cycle prolonged in the dual-species biofilms. Biofilm formation and adhesion of mono-and dual-species at 4 or 15°C were significantly higher than at 30°C during the same phase. The culture supernatant extracts of the two spoilage strains greatly inhibited biofilm development to each other. Conclusions: Shewanella baltica and P. fluorescens had different biofilm and pellicle characteristics, and the inhibitory development on dual-species biofilm was associated with the competitive interaction by the two psychrotrophic spoilage bacteria. Significance and Impact of the Study: This work contributes to a better understanding of interactive behaviour of multispecies biofilm communities by psychrotrophic spoilage bacteria at low temperature, which could contribute to further control contamination of spoilage organism during the preservation and processing of aquatic products.

show abstract

Influence of incubation conditions on the formation of model biofilms byListeria monocytogenesandSalmonellaTyphimurium on abiotic surfaces

Cited by 32 publications

References 32 publications

Inactivation of Single Strains of Listeria monocytogenes and Salmonella Typhimurium Planktonic Cells Biofilms With Plasma Activated Liquids

Inactivation of Single Strains of Listeria monocytogenes and Salmonella Typhimurium Planktonic Cells Biofilms With Plasma Activated Liquids

Dual-Species Model Biofilm Consisting of Listeria monocytogenes and Salmonella Typhimurium: Development and Inactivation With Cold Atmospheric Plasma (CAP)

Competitive interaction on dual‐species biofilm formation by spoilage bacteria, Shewanella baltica and Pseudomonas fluorescens

Contact Info

Product

Resources

About