Biodegradation of 2,4,6-Trinitrotoluene (TNT) with Bacteria Isolated from TNT-polluted Waste Pink Water

  • Zehra Gün Gök Department of Bioengineering, Faculty of Engineering, Kırıkkale University, Yahsihan, 71450 Kırıkkale, Turkey
  • Murat İnal Department of Bioengineering, Faculty of Engineering, Kırıkkale University, Yahsihan, 71450 Kırıkkale, Turkey
  • Mustafa Yiğitoğlu Department of Bioengineering, Faculty of Engineering, Kırıkkale University, Yahsihan, 71450 Kırıkkale, Turkey

Abstract

In this study, bacterial strains that can use TNT as a nitrogen source isolated from TNT contaminated pink water. We isolated 5 bacterial strains and the isolated bacteria were cultured in medium containing TNT and TNT degradation capacities of isolates were determined by spectrophotometric analysis. According to the results of the analysis that have done, 3 bacterial isolates that have high TNT degradation capacity were selected and the isolates were identified with firstly Gram-staining then with 16S rRNA sequence analysis method. According to the sequence of 16S rRNA, water isolates were identified as Stenotrophomonas maltophilia (SU K2), Klebsiella pneumoniae (SU K3), Raoultella planticola (SU K4). During the TNT degradation studies, at the end of 24 h incubation time, in the medium containing 100 mg/L TNT, TNT degradation rate for SU K2, SU K3 and SU K4 were determined 70 %, 96 % and 93 % respectively. 4-aminodinitrotoluene and 2-aminodinitrotoluene accumulations were detected in the culture medium of all isolates as intermediate products formed during the degradation of TNT by HPLC analysis. Additionally, nitrite accumulation was detected in the culture medium of all isolates and the influence of temperature and pH on the degradation of TNT was also investigated. It was determined that SU K2 isolates have the highest TNT degradation capacity at 35 °C, the others have at 30 °C and all isolates degraded TNT fastest at pH 7. The results of the study show that the new isolates can be useful for the removal of TNT in a wastewater treatment system.

Keywords: biodegradation, trinitrotoluene, contaminated water, isolation of bacteria
Published online
2019-03-27
How to Cite
Gün Gök, Z., İnal, M. and Yiğitoğlu, M. (2019) “Biodegradation of 2,4,6-Trinitrotoluene (TNT) with Bacteria Isolated from TNT-polluted Waste Pink Water”, Periodica Polytechnica Chemical Engineering, 63(3), pp. 459-468. doi: https://doi.org/10.3311/PPch.13390.
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Articles