School of Environmental Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 790‐784, South Korea.
Sci Total Environ. 2012 Oct 1;435-436:563-6. doi: 10.1016/j.scitotenv.2012.07.079. Epub 2012 Aug 19.
The dioxin isomer 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TeCDD) has been reported as the deadliest compound known to science. Due to its highly recalcitrant nature and low bioavailability, it is stubborn toward bioremediation and chemical treatment. Efforts to degrade it using one single technique have not accomplished the desired results. In this study, we have tried to develop an integrated 2,3,7,8-TeCDD removal process using palladized iron nanoparticles (Pd/nFe) for initial reductive dechlorination under anoxic conditions and subsequent oxidative biomineralization. Using laboratory synthesized Pd/nFe, 2,3,7,8-TeCDD was completely dechlorinated to form the end product dibenzo-p-dioxin (DD). Oxidative degradation of DD was successfully achieved by growing active cells of a dioxin-degrading microorganism Sphingomonas wittichii RW1 (DSM 6014) under aerobic culture conditions. Metabolite identification was done by high performance liquid chromatography (HPLC) and whole cell protein was measured as the indicator for cell growth. To the best of our knowledge, this is the first report on integrated hybrid degradation method for 2,3,7,8-TeCDD.
二恶英异构体 2,3,7,8-四氯二苯并对二恶英（2,3,7,8-TeCDD）被报道为科学界已知的最致命化合物。由于其高度稳定的性质和低生物利用度，它对生物修复和化学处理具有很强的抵抗力。使用单一技术降解它的努力并未达到预期的结果。在这项研究中，我们试图开发一种使用钯化铁纳米粒子（Pd/nFe）的综合 2,3,7,8-TeCDD 去除工艺，用于初始缺氧条件下的还原脱氯和随后的氧化生物矿化。使用实验室合成的 Pd/nFe，2,3,7,8-TeCDD 被完全脱氯形成最终产物二苯并对二恶英（DD）。通过在好氧培养条件下生长二恶英降解微生物食烷菌（Sphingomonas wittichii RW1（DSM 6014）的活性细胞，成功地实现了 DD 的氧化降解。通过高效液相色谱（HPLC）进行代谢物鉴定，并将全细胞蛋白作为细胞生长的指标进行测量。据我们所知，这是关于 2,3,7,8-TeCDD 的综合混合降解方法的首次报道。
