The Oxidative Microbial Degradation of 2,4,6-Trinitrotoluene (TNT)
Stenger, Mary Ruth
MetadataShow full item record
The explosive nature, toxicity and mutagenic capabilities of explosives make them a primary environmental concern. The most commonly used explosive is 2,4,6-trinitrotoluene (TNT). The problem of cleaning up many of the contaminated sites in the environment can be addressed using oxidative microbial degradation. Several bacteria which are believed to catabolize TNT as a carbon source have been isolated from soil. Biochemical tests were used to identify these bacteria. Both mixed and pure cultures were grown with succinate as a supplemental carbon source, as well as TNT since the bacteria had to be actively growing before optimal utilization of TNT could take place. Mixed cultures of these bacteria were tested for growth on six separate aromatic compounds as their sole carbon sources, and were foundto grow on only benzyl alcohol and benzaldehyde. Use of a pre-exposure to toluene and benzyl alcohol as it affected growth on TNT was also tested. Mixed cultures exposed to toluene before addition of TNT appeared to have enzymes induced which increased the degradation of TNT, while pre-exposure to benzyl alcohol had no effect. TNT may be converted to toluene by oxidative removal of the nitro groups at which point degradation is slowed by the presence of a large amount of toluene which can be toxic if concentrations accumulate to too high a level.