A bacterial strain of Pseudomonas aeruginosa AE-1-3, isolated from soil was used to remove NH4+ and NO3-- simultaneously in an anaerobic environment containing 0.1% NH4NO3 and 3% glucose in the medium. After preliminary screening, eight isolates were obtained, which were evaluated for their potential to decompose NH4+ and NO3--. Each experimental investigation was carried out for 15 days under controlled laboratory conditions by varying the concentrations of glucose (0--3%). The bacterial strain, AE-1-3 showed 100% removal of both NH4+ and NO3--. The effect of metal ions in combinations Of Cu2+, Zn (2+), Sn (2+) were also studied to ascertain the performance. The results revealed that NO3-- could be removed completely in 9 days at 3 mu M concentrations of the three metal ions, while 33% of NH4+ remained in 0.1% NH4NO3 medium with 0.5% glucose in the absence of these three ions. (C) 2006 Elsevier Ltd. All rights reserved.