ASSESSMENT OF THE ADSORPTION OF AEROMONAS HYDROPHILA ON POLYTHENE IN SODIUM HYPOCHLORITE AND HYDROGEN PEROXIDE TREATED WATER

Abstract

A study was carried out on Aeromonashydrophilaadhesion to polythene fragment at different cell growth phases in aquatic microcosm. The main purpose of this study was to assess adsorption capacity, adsorption intensity and kinetics of Aeromonashydrophilaon polythene in sodium hypochlorite(NaOCl) andhydrogen peroxide (H2O2)disinfected water.The mean abundance of adheredA. hydrophilasometimes reached 28 and 111CFU.cm-2respectively in NaOCl and H2O2treated water. The adsorption capacities of A. hydrophilacells fluctuated between 1 and 2.12x1057and between 1 and 2.29x1027adhered cells.cm-2in NaOCl and H2O2disinfected water respectively. The adsorption intensities of this bacterium ranged from -45.81 to 3.49x1019and from 0.16 to 2.29x1027respectively in NaOCl and H2O2treated water. Adsorption capacity and adsorption intensity of A. hydrophilacells on polythene in NaOCl treated water were greater than that obtained in water disinfected with H2O2. Adhesion kinetics of A. hydrophilacells oscillated between 0.001 and 0.930 adhered cell.cm-2.h-1. Adsorption kinetics seem resulted from interactions between bacterial cells and substrates, and depended both on the fragment type and bacterial species. The values of A. hydrophilasurface hydrophobicity fluctuated between 65.11 and 92.74% in NaOCl disinfected water and between 63.38 and 89.41% in H2O2 treated water. The mean values of contact angle ranged from 83.1±0.6 to 85.8±0.8°.Adhesion of A. hydrophilaon polythene is mediated amongst others by cell growth phases, cell surface hydrophobicity, cell kinetic adhesion, adsorption capacity and adsorption intensity.

Keywords

• adsorption capacity
• adsorption intensity
• kinetic adhesion
• disinfectants
• cell growth phases
• a. hydrophila