Disruption of Pseudomonas aeruginosa Adherent Cells by NaCl and NaOCl in Drinking Water

The aim of this study was to compare and explain the disruptive effect of sodium chloride and sodium hypochlorite on the adherent cells of P. aeruginosa on glass slides. To this end, the surface characteristics of glass slides and P. aeruginosa were estimated using the contact angle method. In addition, the effects of NaCl and NaOCl on the attachment of the adherent cells were revealed using optical microscopy. The contact angle data showed moderate effects of NaCl and NaOCl on the P. aeruginosa surface, which became faintly more hydrophilic (21.9 mJ/m 2 , 51.1 mJ/m 2 ) and a stronger electrons donor (53.4 mJ/m 2 , 54.3 mJ/m 2 ). NaCl reversed the hydrophobicity of glass, with its surface becoming very hydrophobic (− 31.7 mJ/m 2 ) and a weak electrons donor (7.4 mJ/m 2 ), whereas NaOCl enhanced the hydrophobicity of glass (49.3 mJ/m 2 ) and its electrons donor character (62.7 mJ/m 2 ). The optical microscopy showed that NaCl caused a clear and progressive disruption of the colonization, while NaOCl had no effect. Briefly, this study suggests that a combination of NaCl and NaOCl may solve the problem of P. aeruginosa installation in water tracks.