Enhanced biodegradation of 2,4,6-trinitrotoluene (TNT) with various supplemental energy sources

The biodegradation of 2,4,6-trinitrotoluene (TNT) was performed on a laboratory scale using P. putida originally isolated from explosive-contaminated soil. One hundred mg/l of TNT was completely degraded within 20 h under optimum conditions. Various supplemental energy sources (carbon sources, nitrogen sources, and surfactant) were tested, with the main objective of identifying an inexpensive source and enhancing the degradation rate for large-scale biodegradation. Based on the degradation rate, molasses was selected as a possible supplemental carbon source, along with NH₄Cl and Tween 80 as a nitrogen source and surfactant, respectively. The degradation rate increased about 3.3 fold when supplemental energy sources were added and the degradation rate constant increased from 0.068 h^-1 to 0.224 h^-1. These results appear to be promising in application of the process to TNT-contaminated soil applications.