Growth dynamic of biofilm-associated in freshwater on various materials.

In industrial water systems, the occurrence of biofilm-associated pathogenic free-living amoebae (FLA) such as is a potential hygienic problem, and factors associated with its occurrence remain poorly understood. This study aimed to evaluate the impact of four cooling circuit materials on the growth of in a freshwater biofilm formed at 42°C and under a hydrodynamic shear rate of 17 s (laminar flow): polyvinyl chloride, stainless steel, brass, and titanium. Colonization of the freshwater biofilms by was found to be effective on polyvinyl chloride, stainless steel, and titanium.

Challenges and applications of nitrate-reducing microbial biocathodes.

Bioelectrochemical systems which employ microbes as electrode catalysts to convert chemical energy into electrical energy (or conversely), have emerged in recent years for water sanitation and energy recovery. Microbial biocathodes, and especially those reducing nitrate are gaining more and more attention. The nitrate-reducing biocathodes can efficiently treat nitrate-polluted wastewater.

Assessment of an anti-scale low-frequency electromagnetic field device on drinking water biofilms.

Low intensity and very low-frequency electromagnetic fields (EMF) used for preventing scaling in water distribution systems were tested for the first time for their potential impact on drinking water biofilms. The assays were carried out in laboratory-scale flow-through reactors that mimic water distribution systems. The drinking water biofilms were not directly exposed to the core of the EMF generator and only subjected to waterborne electromagnetic waves.

Influence of cytochrome charge and potential on the cathodic current of electroactive artificial biofilms.

An electroactive artificial biofilm has been optimized for the cathodic reduction of fumarate by Shewanella oneidensis. The system is based on the self-assembly of multi-walled carbon nanotubes with bacterial cells in the presence of a c-type cytochrome. The aggregates are then deposited on an electrode to form the electroactive artificial biofilm.

Design of a rotating disk reactor to assess the colonization of biofilms by free-living amoebae under high shear rates.

The present study was aimed at designing and optimizing a rotating disk reactor simulating high hydrodynamic shear rates (γ), which are representative of cooling circuits. The characteristics of the hydrodynamic conditions in the reactor and the complex approach used to engineer it are described. A 60 l tank was filled with freshwater containing free-living amoebae (FLA) and bacteria.