The purpose of this study was to investigate biological dentirification of wastewater by pure cultures isolated from activated sludge of wastewater treatment plant of Khenchela (Eastern Algeria). Experiments were performed in batch reactor under anaerobic conditions. Three pure strains were isolated and identified as Enterobacter cloacae, Pseudomonas luteola and Aeromonas hydrophila Three carbon sources were used in this work; glucose, methanol and lactose. High denitrification was obtained at 2000 ppm for different carbon sources. Kinetic of bacterial growth and denitrification were studied. We show that bacterial growth rate directly influences nitrate removal from the medium and the use of glucose as carbon source provide high denitrification rate than methanol and lactose. These strains isolated from activated sludge will be used to develop new biosensors applied to the detection and determination of nitrate in real water.
