Effect of organic and metal ion concentration on the simultaneous biological removal of NH4+ and NO3- under anaerobic condition

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+, Zn2+, Sn2+ were also studied to ascertain the performance. The results revealed that NO3- could be removed completely in 9 days at 3 μM 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.