REDUCTION AND ACETYLATION OF 2,4-DINITROTOLUENE BY A PSEUDOMONAS-AERUGINOSA STRAIN

Aerobic and anoxic biotransformation of 2,4-dinitrotoluene (DNT) was e xamined by using a Pseudomonas aeruginosa strain isolated from a plant treating propellant manufacturing wastewater. DNT biotransformation i n the presence and absence of oxygen was mostly reductive and was repr esentative of the type of cometabolic transformations that occur when a high concentration of an easily degradable carbon source is present. P. aeruginosa reduced both nitro groups on DNT, with the formation of mainly 4-amino-2-nitrotoluene and 2-amino-4-nitrotoluene and small qu antities of 2,4-diaminotoluene. Acetylation of the arylamines was a si gnificant reaction. 4-Acetamide-2-nitrotoluene and the novel compounds 2-acetamide-4-nitrotoluene, 4-acetamide-2-aminotoluene, and 2,4-diace tamidetoluene were identified as DNT metabolites. The biotransformatio n of 2,4-diaminotoluene to 4-acetamide-2-aminotoluene was 24 times fas ter than abiotic transformation. 2-Nitrotoluene and 4-nitrotoluene wer e also reduced to their corresponding toluidines and then acetylated. However, the yield of 4-acetamidetoluene was much higher than that of 2-acetamidetoluene, demonstrating that acetylation at the position par a to the methyl group was favored.