%0 Journal Article
%T Mixture of Sodium Hypochlorite and Hydrogen Peroxide on Adhered Aeromonas hydrophila to Solid Substrate in Water: Impact of Concentration and Assessment of the Synergistic Effect
%A Chr¨¦tien Lontsi Djimeli
%A Antoine Tamsa Arfao
%A Olive V. Noah Ewoti
%A Mireille Ebiane Nougang
%A Marlyse L. Moungang
%A Genevi¨¨ve Bricheux
%A Mo£¿se Nola
%A T¨¦lesphore Sime-Ngando
%J International Journal of Bacteriology
%D 2014
%I Hindawi Publishing Corporation
%R 10.1155/2014/121367
%X The synergistic effects of the combined treatments of NaOCl and H2O2 on the elimination of A. hydrophila adhered to polythene under static and dynamic conditions were evaluated. The concentrations 0.1, 0.2, and 0.3 NaOCl and 0.5, 1, and 1.5 H2O2 were used. The contact periods were 180, 360, 540, and 720 minutes. The abundance of cells adhered reached 2.47 and 2.27 units (log (CFU/cm2)), respectively, under static and dynamic conditions after action of the mixture of disinfectants, whereas it reached 2.41 and 3.39 units (log (CFU/cm2)) after action of NaOCl and H2O2 alone, respectively. Increase in the incubation period resulted in a significant decrease in the abundance of cells adhered when the mixture of 0.3 NaOCl and 1.5 H2O2 was used ( ). For each cell growth phase, there was a significant difference amongst the mean densities of cells adhered after action of the mixture of disinfectants ( ). Although the Freundlich isotherm parameters relatively varied from one experimental condition to another, the value registered in the exponential growth phase was relatively higher in static state than in dynamic regime; cells adhered under dynamic condition seem more sensitive to the synergistic action than those adhered under static condition. 1. Introduction The drinking water distribution network is a source of disquiet regarding the contamination of water during delivery and regrowth of microorganisms that survive after treatment [1]. It is often the scene of many physicochemical and biological reactions resulting from interactions between disinfectants, pipe walls, and the free and fixed biomass [2]. The presence of natural organic matter provides a food source for bacteria that can colonize the inner walls of distribution pipes, forming biofilms that protect and support the growth of microorganisms, some of which are associated to hostile effect on human health [1] and others through their interactions with disinfectants and pipe walls are sometimes the cause of the deterioration of the organoleptic properties of the water supply [2, 3]. In recent years, World Health Organization recognizes A. hydrophila as an opportunistic pathogen, implicated as a pathogenic agent in gastroenteritis, septicemia, cellulitis, colitis, meningitis, and respiratory infections [4¨C6]. To prevent bacterial regrowth, a residual of a disinfectant is maintained in the water distribution network. Previous work has shown that the bacterium A. hydrophila is widespread in the environment, especially in water intended for human consumption [7, 8]. Its concentration can sometimes reach
%U http://www.hindawi.com/journals/ijb/2014/121367/