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AAI9625172 Freedman, David L. Noguera Camacho, Daniel Ricardo 2011-05-07T13:41:32Z 2011-05-07T13:41:32Z 10000-01-01 1996 The anoxic biotransformation of 2,4-dinitrotoluene (DNT) was evaluated. Two denitrifying enrichment cultures were developed, one with inoculum from the biological treatment plant at Radford Army Ammunition Plant (RAAP), which was acclimated to treatment of DNT munitions wastes, the other derived from an activated sludge not routinely exposed to nitroaromatics (Urbana). DNT was cometabolically transformed by both cultures when an external carbon source was supplied. Initial transformations were reductive, with the transient accumulation of 2-amino-4-nitrotoluene, 4-amino-2-nitrotoluene, and 2,4-diaminotoluene. In addition, formation of 2-nitrotoluene and 4-nitrotoluene occurred by reductive deamination of the corresponding aminonitrotoluenes. 6-Nitroindazole was also identified as a significant metabolite from DNT in both cultures. A radioactive $\rbrack\sp{14}\rm C\lbrack$-DNT tracer, used to track the fate of the DNT, revealed that DNT was not mineralized in either culture. In addition, a significant fraction of the original DNT was transformed to insoluble products (33-40%), possibly by polymerization of 2,4-diaminotoluene. Furthermore, there was a significant difference in the composition of the soluble products from each culture. In the Urbana enrichment, most of the soluble products were hydrophilic, while in the RAAP enrichment, the majority of the products were hydrophobic. Ion pairing chromatography was used to partially characterize hydrophilic products in the Urbana enrichment. Approximately equal amounts of negatively charged and neutral compounds were detected. Mass spectroscopy of the hydrophobic products in the RAAP enrichment indicated the presence of the acetylated metabolites 4-acetamidetoluene and 4-acetamide-2-nitrotoluene. A strain of Pseudomonas aeruginosa (strain LCA) was isolated from the RAAP enrichment and evaluated for its ability to biotransform DNT and other nitrotoluenes. Reduction of nitro groups to amines and N-acetylation were the most important transformations. Although reduction and acetylation of the nitro groups located ortho and para to the methyl moiety was possible, acetylation at the para position was the fastest reaction, while acetylation at the ortho position was kinetically unfavorable. The results from this research demonstrated that denitrification alone was not a satisfactory biological process for the treatment of DNT in munitions wastes, because mineralization did not occur and the products identified exhibited similar toxicological concerns as DNT. Made available in DSpace on 2011-05-07T13:41:32Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9625172.pdf: 9032465 bytes, checksum: fea01b8c1c7aad9fdcc7c10d598fe60f (MD5) Previous issue date: 1996 Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:57:58Z Item is restricted indefinitely. Restriction data tranferred 2014-07-01T11:27:14-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission ETDs are only available to UIUC Users without author permission U of I Only (UMI)AAI9625172 http://hdl.handle.net/2142/22491 eng Copyright 1996 Noguera Camacho, Daniel Ricardo Biology, Microbiology Engineering, Civil Engineering, Environmental Biological transformation of 2,4-dinitrotoluene under denitrifying conditions text Civil and Environmental Engineering Civil and Environmental Engineering University of Illinois at Urbana-Champaign Dissertation Ph.D.