Inactivation kinetics of various chemical disinfectants on Aeromonas hydrophila planktonic cells and biofilms

Foodborne Pathog Dis. 2014 May;11(5):346-53. doi: 10.1089/fpd.2013.1682. Epub 2014 Feb 19.

Abstract

The present article focuses on the inactivation kinetics of various disinfectants including ethanol, sodium hypochlorite, hydrogen peroxide, peracetic acid, and benzalkonium chloride against Aeromonas hydrophila biofilms and planktonic cells. Efficacy was determined by viable plate count and compared using a modified Weibull model. The removal of the biofilms matrix was determined by the crystal violet assay and was confirmed by field-emission scanning electron microscope. The results revealed that all the experimental data and calculated Weibull α (scale) and β (shape) parameters had a good fit, as the R(2) values were between 0.88 and 0.99. Biofilms are more resistant to disinfectants than planktonic cells. Ethanol (70%) was the most effective in killing cells in the biofilms and significantly reduced (p<0.05) the biofilms matrix. The Weibull parameter b-value correlated (R(2)=0.6835) with the biofilms matrix removal. The present findings deduce that the Weibull model is suitable to determine biofilms matrix reduction as well as the effectiveness of chemical disinfectants on biofilms. The study showed that the Weibull model could successfully be used on food and food contact surfaces to determine the exact contact time for killing biofilms-forming foodborne pathogens.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aeromonas hydrophila / drug effects*
  • Aeromonas hydrophila / growth & development
  • Benzalkonium Compounds / pharmacology
  • Biofilms / drug effects*
  • Colony Count, Microbial
  • Disinfectants / pharmacology*
  • Ethanol / pharmacology
  • Hydrogen Peroxide / pharmacology
  • Microbial Sensitivity Tests
  • Nonlinear Dynamics
  • Peracetic Acid / pharmacology
  • Sodium Hypochlorite / pharmacology
  • Tomography, Emission-Computed, Single-Photon

Substances

  • Benzalkonium Compounds
  • Disinfectants
  • Ethanol
  • Hydrogen Peroxide
  • Sodium Hypochlorite
  • Peracetic Acid