TNT生物代谢的可能途径

因具有毒性和三致作用,污染环境介质中TNT去除倍受关注。为了能更有效地去除TNT,在总结大量文献的基础上,主要从TNT反应性质方面探讨其生物代谢途径。TNT的结构决定了TNT难于生物氧化、易于生物还原。TNT还原以硝基基团的序批式还原为主,一些中间代谢产物还会相互作用生成聚合物,产物TAT需在严格厌氧条件下生成;TNT的芳烃环也可实现加氢脱硝还原,以利于下一步反应的进行;此外,TNT可同时发生硝基还原和芳烃环还原,两条途径的中间产物还会相互作用生成一些聚合物。TNT的氧化以间接氧化为主,直接氧化很少。由于TNT本身结构的复杂性、反应条件或介质的不同、中间产物的多样性,使得TNT代谢途径还具有很大的不确定性,故仍需进行深入研究。

The Possible Pathway of Bio-metabolization of TNT

As TNT(2,4,6-Trinitrotoluene) is toxic,carcinogenic,teratogenic,and mutagenic,the extensive use of TNT poses environmental risks.Hence,removal of TNT from soil,surface water and ground water has attracted much attention.For purpose of removing TNT from environment effectively,and based on a lot of literatures and according to reaction property,the metabolic pathways of TNT removal are discussed.TNT is easy to be reduced and difficult to be oxidized due to its structure.The nitroreduction is the main reduction pathway and TNT is reduced to the nitroso,hydroxylamine,amine derivatives which can interact to form some polymers.Moreover,TAT can be produced only in strict anaerobic condition;aromatic ring reduction pathways are intuitively interesting,as they might lead to the production of sterically simpler compounds through the removal of nitro groups;both nitroreduction and aromatic ring reduction can occur simultaneously,and intermediates from both pathways can interact to form polymers.The oxidation of TNT occurs mainly through the indirect metabolic pathway;the direct oxidation of TNT is rare.The biological metabolic pathway is uncertain due to the structure complex of TNT,the difference of reaction condition and the diversity of intermediates,so it is necessary to investigate the metabolic pathway of TNT deeply.