Impact of Ferrihydrite and Anthraquinone-2,6-Disulfonate on the Reductive Transformation of 2,4,6-Trinitrotoluene by a Gram-Positive Fermenting Bacterium

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• 作者：Thomas Borch ; William P. Inskeep ; Jace A. Harwood ; and Robin Gerlach
• 刊名：Environmental Science & Technology
• 出版年：2005
• 出版时间：September 15, 2005
• 年：2005
• 卷：39
• 期：18
• 页码：7126 - 7133
• 全文大小：531K
• 年卷期：v.39,no.18(September 15, 2005)
• ISSN：1520-5851

文摘

Batch studies were conducted to explore differences inthe transformation pathways of 2,4,6-trinitrotoluene (TNT)reduction by a Gram-positive fermenting bacterium(Cellulomonas sp. strain ES6) in the presence and absenceof ferrihydrite and the electron shuttle anthraquinone-2,6-disulfonate (AQDS). Strain ES6 was capable of TNT andferrihydrite reduction with increased reduction rates in thepresence of AQDS. Hydroxylaminodinitrotoluenes, 2,4-dihydroxylamino-6-nitrotoluene (2,4-DHANT), and tetranitroazoxytoluenes were the major metabolites observed inferrihydrite- and AQDS-free systems in the presence ofpure cell cultures. Ferrihydrite enhanced the production ofamino derivatives because of reactions with microbiallyproduced surface-associated Fe(II). The presence of AQDSin the absence of ferrihydrite promoted the fast initialformation of arylhydroxylamines such as 2,4-DHANT. However,unlike in pure cell systems, these arylhydroxylamineswere transformed into several unidentified polar products.When both microbially reduced ferrihydrite and AQDSwere present simultaneously, the reduction of TNT wasmore rapid and complete via pathways that would have beendifficult to infer solely from single component studies.This study demonstrates the complexity of TNT degradationpatterns in model systems where the interactions amongbacteria, Fe minerals, and organic matter have a pronouncedeffect on the degradation pathway of TNT.