title: Metabolite production during transformation of 2,4,6-trinitrotoluene (TNT) by a mixed culture acclimated and maintained on crude oil-containing media.
abstract: Metabolites formed during 2,4,6-trinitrotoluene (TNT) removal by a mixed bacterial culture (acclimated and maintained on crude oil-containing medium and capable of high rates of TNT removal) were characterized. In resting cell experiments in the absence of glucose, 46.2 mg/l TNT were removed in 171 h (87.5% removal), with a combined total formation of 7.7 mg/l amino-4,6-dinitrotoluene (ADNT) and 0.3 mg/l 4,4'-azoxytetranitrotoluene and 2',4-azoxytetranitrotoluene, leaving 70% of the initial TNT unaccounted for. In the presence of glucose, resting cells removed 45.4 mg/l TNT in 49 h (95.5% removal), with 9.1 mg/l ADNT and 2.4 mg/l azoxy compounds being produced, leaving 70.3% of the TNT unaccounted for. Growing cells (glucose present) were capable of removing 44.2 mg/l TNT within 21 h (97.9% removal), with the concomitant formation of 1.8 mg/l ADNTs and 2.2 mg/l azoxy compounds. Denitrated TNT in the form of 2,6-dinitrotoluene was also produced in growing cells with a maximum amount of 1.31 mg/l after 28 h, followed by a slight decrease with time, leaving 88.5% of the initial TNT unaccounted for after 171 h. Radiolabeled (14)C-TNT studies revealed 4.14% mineralization after an incubation period of 163 days with growing cells.
authors.affiliation: Department of Biology, University of Waterloo, Waterloo, N2L 3G1, Ontario, Canada.
authors.forename: Jason T
authors.initials: JT
authors.lastname: Popesku
authors.forename: Ajay
authors.initials: A
authors.lastname: Singh
authors.forename: Jian-Shen
authors.initials: JS
authors.lastname: Zhao
authors.forename: Jalal
authors.initials: J
authors.lastname: Hawari
authors.forename: Owen P
authors.initials: OP
authors.lastname: Ward
mesh_terms: D000814:Aniline Compounds / Q000378:metabolism; D001391:Azo Compounds / Q000378:metabolism; D001419:Bacteria / Q000378:metabolism*; D001673:Biodegradation, Environmental; D004136:Dinitrobenzenes / Q000378:metabolism; D004783:Environmental Microbiology; D005947:Glucose / Q000378:metabolism; D007700:Kinetics; D010578:Petroleum / Q000382:microbiology*; D013997:Time Factors; D014303:Trinitrotoluene / Q000378:metabolism*
chemical_list: D000814:Aniline Compounds; D001391:Azo Compounds; D004136:Dinitrobenzenes; D010578:Petroleum; D014303:Trinitrotoluene; C035208:2-amino-4,6-dinitrotoluene; C097194:2,2',6,6'-tetranitro-4,4'-azoxytoluene; C023514:2,6-dinitrotoluene; D005947:Glucose