Physiological changes induced by the quaternary ammonium compound benzyldimethyldodecylammonium chloride on Pseudomonas fluorescens

Ferreira, Carla; Pereira, Ana Margarida; Pereira, Maria do Carmo; Melo, L. F.; Simões, Manuel

doi:10.1093/jac/dkr028

Cited by 110 publications

(77 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The results obtained in this study also indicate that the B. cereus biofilms had a basal layer strongly resistant to removal by chemical and mechanical action, regardless of the rw value under which the biofilms were formed. Even if the biofilms were treated with a biocide with recognized antimicrobial efficacy (Ferreira et al, 2010(Ferreira et al, , 2011, BDMDAC only promoted modest biofilm removal.…”

Section: Resultsmentioning

confidence: 99%

The effect of shear stress on the formation and removal of Bacillus cereus biofilms

Lemos

Mergulhão

Melo

et al. 2015

Food and Bioproducts Processing

View full text Add to dashboard Cite

A b s t r a c tThe influence of the shear stress (rw) under which biofilms were formed was assessed on their susceptibility to removal when exposed to chemical and mechanical stresses. A rotating cylinder reactor was used to form biofilms, allowing the simulation of rw conditions similar to those found in industrial settings, particularly in areas with low rw like elbows, corners, valves and dead zones. Bacillus cereus was used as a model bacterium for biofilm formation.Biofilms were formed on AISI316 stainless steel cylinders under different rw (estimated at 0.02, 0.12 and 0.17 Pa) for 7 days. Some phenotypic characteristics, including thickness, biomass production, cellular density and extracellular proteins and polysaccharides content were assessed. Biofilm density was found to increase significantly with rw while the thickness decreased. Also, biofilms formed at 0.02 Pa had lowest biomass content, cell density and extracellular polysaccharide content. Those characteristics were not statistically different for the biofilms formed under 0.12 and 0.17 Pa.Ex situ tests were performed by treating the biofilms with the biocide benzyldimethyldodecyl ammonium chloride (BDMDAC), followed by exposure to increasing rw conditions, up to 1.84 Pa (whereas the maximum rw used during growth was 0.17 Pa). The biofilms formed under low rw were more resistant to removal caused by the BDMDAC action alone. Those formed under higher rw were more resistant to the mechanical and the combined chemical and mechanical treatments. The amount of biofilm remaining on the cylinders, after both treatments was statistically similar for biofilms formed under 0.12 and 0.17Pa. The resistance of biofilms to removal by mechanical treatment (alone and combined with BDMDAC) was related to the amount of matrix polysaccharides.However, none of the methods investigated were able to remove all the biofilm from the cylinders. IntroductionThere is a lack of efficient strategies to clean stagnant zones in industrial plants (Brooks and Flint, 2008). Crevices, corners, dead zones, valves or areas where the mixing rate is low are almost inevitable. Stagnation promotes bacterial accumulation, ultimately leading to biofouling (Manuel et al., 2010). Biofouling is a damaging problem, affecting the energetic efficiency of industrial processes, causing corrosion of the surfaces, decreasing product quality and eventually promoting the spread of pathogens and resistant infectious diseases (Costerton et al., 1999;Ludensky, 2003;Srey et al., 2013). In industrial settings, surface disinfection is usually focused on the use of biocides, aiming to inactivate the microorganisms (Cloete et al., 1998;Faille et al., 2013). Since biofilms are complex biological structures adhered to a sur-face, these strategies often fail, as the removal of biomass is neglected. Hence, cleaning the biomass from the surfaces is fundamental for controlling biofilm development (Flemming, 2011).In the biofilm formation process, the hydrodynamic conditions define the transport of the cells, oxyg...

show abstract

Section: Resultsmentioning

confidence: 99%

The effect of shear stress on the formation and removal of Bacillus cereus biofilms

Lemos

Mergulhão

Melo

et al. 2015

Food and Bioproducts Processing

View full text Add to dashboard Cite

show abstract

“…The charge properties of the cell surfaces can play a vital role in the microbial homeostasis and resistance to antimicrobial agents (Ferreira et al 2011). Under physiological conditions, bacterial cells have normally negative surface charge, due to the presence of anionic groups (e.g.…”

Section: Discussionmentioning

confidence: 99%

Antibacterial activity and mode of action of selected glucosinolate hydrolysis products against bacterial pathogens

et al. 2014

View full text Add to dashboard Cite

Plants contain numerous components that are important sources of new bioactive molecules with antimicrobial properties. Isothiocyanates (ITCs) are plant secondary metabolites found in cruciferous vegetables that are arising as promising antimicrobial agents in food industry. The aim of this study was to assess the antibacterial activity of two isothiocyanates (ITCs), allylisothiocyanate (AITC) and 2-phenylethylisothiocyanate (PEITC) against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Listeria monocytogenes. The antibacterial mode of action was also characterized by the assessment of different physiological indices: membrane integrity, intracellular potassium release, physicochemical surface properties and surface charge. The minimum inhibitory concentration (MIC) of AITC and PEITC was 100 μg/mL for all bacteria. The minimum bactericidal concentration (MBC) of the ITCs was at least 10 times higher than the MIC. Both AITC and PEITC changed the membrane properties of the bacteria decreasing their surface charge and compromising the integrity of the cytoplasmatic membrane with consequent potassium leakage and propidium iodide uptake. The surface hydrophobicity was also non-specifically altered (E. coli and L. monocytogenes become less hydrophilic; P. aeruginosa and S. aureus become more hydrophilic). This study shows that AITC and PEITC have strong antimicrobial potential against the bacteria tested, through the disruption of the bacterial cell membranes. Moreover, phytochemicals are highlighted as a valuable sustainable source of new bioactive products.

show abstract

“…60 When applying an electric field across a bacterial suspension, bacteria with non-zero zeta potential migrate towards the electrode of the opposite charge, with a velocity proportional to the magnitude of their zeta potential. 1 The results obtained from zeta potential measurements with S. aureus and E. coli in the absence and presence of CAF and its alkyl esters are shown in Table 4. Bacterial cells normally present a negative surface charge, due to the presence of anionic groups in their membranes, such as carboxylate and phosphate groups.…”

Section: Effects Of Caffeic Acid and Alkyl Esters On The Physicochemimentioning

confidence: 99%

“…1 For this purpose, antibacterial agents such as biocides and antibiotics are usually employed 2,3 and their selection differ by the extent of their pharmacological specificity and of their degree of mammalian toxicity. Antibiotics usually have a single biochemical target (i.e., a selective toxicity) and are used against bacterial infections in human beings and animals.…”

Section: Introductionmentioning

confidence: 99%

“…On the other hand, biocides generally possess several distinct targets, with diverse susceptibilities (i.e., a broad spectrum of usage) and are often regarded as antiseptics (used externally on human skin), disinfectants (for surface sanitizing), and/or preservatives (incorporated in pharmaceutical, cosmetic or other types of products to prevent microbial contamination). 1,2,4 However, these agents have been widely recognized as being used inappropriately, and constantly subjected to overuse, underuse and general misuse over the years. On bacteria, these type of mishandlings create a selective pressure for the development of bacterial resistance and/or multidrug resistance to these compounds, with resistance being transmitted within and between individuals.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Fine-tuning of the hydrophobicity of caffeic acid: studies on the antimicrobial activity against Staphylococcus aureus and Escherichia coli

et al. 2015

View full text Add to dashboard Cite

The increased bacterial multidrug resistance caused by inappropriate use and overuse of antimicrobials is a global concern. To circumvent this issue, a quest for the development of new active agents has been widely recognized. Some phytochemical products, produced by plants as part of their chemical defense strategies, are regarded as new stimulus to develop novel antimicrobials that are not as vulnerable as current drugs to bacterial resistance mechanisms. In this study, the antimicrobial activity and mode of action of caffeic acid (CAF) and a series of CAF alkyl esters was assessed against Escherichia coli and Staphylococcus aureus, with the aim of analyzing the influence of the alkyl ester side chain length on the activity. Minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), changes in physicochemical surface properties and intracellular potassium leakage were used as physiological indices for the antimicrobial mode of action. CAF alkyl esters were found to be effective antimicrobial agents against both bacteria. Their activity was directly dependent on their lipophilicity, which affected bacterial susceptibility, the physicochemical properties of the bacteria and the integrity of the membranes. E. coli was less susceptible than S. aureus to the action of the compounds. Longer alkyl side chains were more effective against the Gram-positive bacterium, while medium length alkyl side chain compounds were more effective against the Gram-negative bacterium. Caffeic acid derivatives are proposed to act as cell permeabilizers, inducing membrane alterations, causing rupture with potassium leakage, particularly on the Gram positive bacterium, and consequent cell death.

show abstract

Physiological changes induced by the quaternary ammonium compound benzyldimethyldodecylammonium chloride on Pseudomonas fluorescens

Cited by 110 publications

References 53 publications

The effect of shear stress on the formation and removal of Bacillus cereus biofilms

The effect of shear stress on the formation and removal of Bacillus cereus biofilms

Antibacterial activity and mode of action of selected glucosinolate hydrolysis products against bacterial pathogens

Fine-tuning of the hydrophobicity of caffeic acid: studies on the antimicrobial activity against Staphylococcus aureus and Escherichia coli

Contact Info

Product

Resources

About