Limits...
In-vitro archaeacidal activity of biocides against human-associated archaea.

Khelaifia S, Brunel JM, Michel JB, Drancourt M - PLoS ONE (2013)

Bottom Line: However, no biocide activity has been reported among these human-associated archaea.Squalamine derivative S1 exhibited a 10-200 higher archaeacidal activity than other tested squalamine derivatives, on the majority of human-associated archaea.As previously reported and due to their week corrosivity and their wide spectrum of antibacterial and antifungal properties, squalamine and more precisely derivative S1 appear as promising compounds to be further tested for the decontamination of medical devices contaminated by human-associated archaea.

View Article: PubMed Central - PubMed

Affiliation: Aix Marseille Université, URMITE, UMR63 CNRS 7278, IRD 198, Inserm 1095, Marseille, France.

ABSTRACT

Background: Several methanogenic archaea have been detected in the human intestinal microbiota. These intestinal archaea may contaminate medical devices such as colonoscopes. However, no biocide activity has been reported among these human-associated archaea.

Methodology: The minimal archaeacidal concentration (MAC) of peracetic acid, chlorhexidine, squalamine and twelve parent synthetic derivatives reported in this study was determined against five human-associated methanogenic archaea including Methanobrevibacter smithii, Methanobrevibacter oralis, Methanobrevibacter arboriphilicus, Methanosphaera stadtmanae, Methanomassiliicoccus luminyensis and two environmental methanogens Methanobacterium beijingense and Methanosaeta concilii by using a serial dilution technique in Hungates tubes.

Principal findings: MAC of squalamine derivative S1 was 0.05 mg/L against M. smithii strains, M. oralis, M. arboriphilicus, M. concilii and M. beijingense whereas MAC of squalamine and derivatives S2-S12 varied from 0.5 to 5 mg/L. For M. stadtmanae and M. luminyensis, MAC of derivative S1 was 0.1 mg/L and varied from 1 to ≥ 10 mg/L for squalamine and its parent derivatives S2-S12. Under the same experimental conditions, chlorhexidine and peracetic acid lead to a MAC of 0.2 and 1.5 mg/L, respectively against all tested archaea.

Conclusions/significance: Squalamine derivative S1 exhibited a 10-200 higher archaeacidal activity than other tested squalamine derivatives, on the majority of human-associated archaea. As previously reported and due to their week corrosivity and their wide spectrum of antibacterial and antifungal properties, squalamine and more precisely derivative S1 appear as promising compounds to be further tested for the decontamination of medical devices contaminated by human-associated archaea.

Show MeSH

Related in: MedlinePlus

Structure of squalamine, chlorhexidine and peracetic acid.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3643942&req=5

pone-0062738-g001: Structure of squalamine, chlorhexidine and peracetic acid.

Mentions: A filtered aqueous solution of each one of the 12 biocides (Figures 1, 2) was anaerobically added at a final 5 mg/L concentration into Hungate tubes [19] containing distilled water; tubes were previously sterilized by autoclaving at 120°C for 30 min under an H2/CO2 (80/20) atmosphere. The in-vitro archaeacidal activity of the biocides was determined by transferring 10E+05 archaea cells/mL of an exponentially growing culture into 4.5 mL of fresh medium containing 0.01, 0.05, 0.1, 0.2, 0.4, 0.8, 1, 5 or 10 mg/L of biocide. Tubes were incubated at 37°C under stirring and archaea growth was observed after a 5-day incubation. Cultures were centrifuged at 11,000 g for three minutes at room temperature, washed with fresh medium to remove traces of biocide and reinoculated into a new culture medium. Control cultures without biocide were incubated in parallel. Growth of archaea was assessed by optical microscopy observation and parallel measurement of methane production using a GC-8A gas chromatograph (Shimadzu, Champs-sur-Marne, France) equipped with a thermal conductivity detector and a Chromosorb WAW 80/100 mesh SP100 column (Alltech, Carquefou, France). N2 at a pressure of 100 kPa was used as the carrier gas. The detector and the injector temperature was 200°C and the column temperature was 150°C. The in-vitro activity of biocide under these culture conditions was verified as follows. Culture media 119, 322, 334 (http://www.dsmz.de) and M.luminyensis medium were supplemented with a final concentration of 0.01, 0.05, 0.1, 0.2, 0.4, 0.8, 1, 5 or 10 mg/L of biocide and were incubated at 37°C in a H2/CO2 (80/20) atmosphere for 10 days. The activity of each biocide was controlled using clinical isolates of Escherichia coli and Staphylococcus aureus[17], [20] in the same culture conditions as the tested archaea. Growth controls with appropriate media instead of derivative dilutions were introduced in all experiments. The minimal archaeacidal concentration (MAC) was defined as the lowest biocide concentration killing archaea organisms. This was measured by observing the inhibition of methane production and the absence of microscopically visible growth of this archaea.


In-vitro archaeacidal activity of biocides against human-associated archaea.

Khelaifia S, Brunel JM, Michel JB, Drancourt M - PLoS ONE (2013)

Structure of squalamine, chlorhexidine and peracetic acid.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3643942&req=5

pone-0062738-g001: Structure of squalamine, chlorhexidine and peracetic acid.
Mentions: A filtered aqueous solution of each one of the 12 biocides (Figures 1, 2) was anaerobically added at a final 5 mg/L concentration into Hungate tubes [19] containing distilled water; tubes were previously sterilized by autoclaving at 120°C for 30 min under an H2/CO2 (80/20) atmosphere. The in-vitro archaeacidal activity of the biocides was determined by transferring 10E+05 archaea cells/mL of an exponentially growing culture into 4.5 mL of fresh medium containing 0.01, 0.05, 0.1, 0.2, 0.4, 0.8, 1, 5 or 10 mg/L of biocide. Tubes were incubated at 37°C under stirring and archaea growth was observed after a 5-day incubation. Cultures were centrifuged at 11,000 g for three minutes at room temperature, washed with fresh medium to remove traces of biocide and reinoculated into a new culture medium. Control cultures without biocide were incubated in parallel. Growth of archaea was assessed by optical microscopy observation and parallel measurement of methane production using a GC-8A gas chromatograph (Shimadzu, Champs-sur-Marne, France) equipped with a thermal conductivity detector and a Chromosorb WAW 80/100 mesh SP100 column (Alltech, Carquefou, France). N2 at a pressure of 100 kPa was used as the carrier gas. The detector and the injector temperature was 200°C and the column temperature was 150°C. The in-vitro activity of biocide under these culture conditions was verified as follows. Culture media 119, 322, 334 (http://www.dsmz.de) and M.luminyensis medium were supplemented with a final concentration of 0.01, 0.05, 0.1, 0.2, 0.4, 0.8, 1, 5 or 10 mg/L of biocide and were incubated at 37°C in a H2/CO2 (80/20) atmosphere for 10 days. The activity of each biocide was controlled using clinical isolates of Escherichia coli and Staphylococcus aureus[17], [20] in the same culture conditions as the tested archaea. Growth controls with appropriate media instead of derivative dilutions were introduced in all experiments. The minimal archaeacidal concentration (MAC) was defined as the lowest biocide concentration killing archaea organisms. This was measured by observing the inhibition of methane production and the absence of microscopically visible growth of this archaea.

Bottom Line: However, no biocide activity has been reported among these human-associated archaea.Squalamine derivative S1 exhibited a 10-200 higher archaeacidal activity than other tested squalamine derivatives, on the majority of human-associated archaea.As previously reported and due to their week corrosivity and their wide spectrum of antibacterial and antifungal properties, squalamine and more precisely derivative S1 appear as promising compounds to be further tested for the decontamination of medical devices contaminated by human-associated archaea.

View Article: PubMed Central - PubMed

Affiliation: Aix Marseille Université, URMITE, UMR63 CNRS 7278, IRD 198, Inserm 1095, Marseille, France.

ABSTRACT

Background: Several methanogenic archaea have been detected in the human intestinal microbiota. These intestinal archaea may contaminate medical devices such as colonoscopes. However, no biocide activity has been reported among these human-associated archaea.

Methodology: The minimal archaeacidal concentration (MAC) of peracetic acid, chlorhexidine, squalamine and twelve parent synthetic derivatives reported in this study was determined against five human-associated methanogenic archaea including Methanobrevibacter smithii, Methanobrevibacter oralis, Methanobrevibacter arboriphilicus, Methanosphaera stadtmanae, Methanomassiliicoccus luminyensis and two environmental methanogens Methanobacterium beijingense and Methanosaeta concilii by using a serial dilution technique in Hungates tubes.

Principal findings: MAC of squalamine derivative S1 was 0.05 mg/L against M. smithii strains, M. oralis, M. arboriphilicus, M. concilii and M. beijingense whereas MAC of squalamine and derivatives S2-S12 varied from 0.5 to 5 mg/L. For M. stadtmanae and M. luminyensis, MAC of derivative S1 was 0.1 mg/L and varied from 1 to ≥ 10 mg/L for squalamine and its parent derivatives S2-S12. Under the same experimental conditions, chlorhexidine and peracetic acid lead to a MAC of 0.2 and 1.5 mg/L, respectively against all tested archaea.

Conclusions/significance: Squalamine derivative S1 exhibited a 10-200 higher archaeacidal activity than other tested squalamine derivatives, on the majority of human-associated archaea. As previously reported and due to their week corrosivity and their wide spectrum of antibacterial and antifungal properties, squalamine and more precisely derivative S1 appear as promising compounds to be further tested for the decontamination of medical devices contaminated by human-associated archaea.

Show MeSH
Related in: MedlinePlus