Sequestration and Oxidation of Cr(III) by Fungal Mn Oxides with Mn(II) Oxidizing Activity
Sequestration and Oxidation of Cr(III) by Fungal Mn Oxides with Mn(II) Oxidizing Activity
复制标题
具有 Mn(II) 氧化活性的真菌锰氧化物对 Cr(III) 的封存和氧化
作者：
Ryohei Suzuki;Y. Tani;H. Naitou;N. Miyata;Kazuya Tanaka
生物锰氧化物因其对多种元素的吸附和氧化能力而在环境保护方面受到越来越多的关注。然而，BMO对Cr（III）的氧化和螯合作用仍然未知。我们准备BMO在液体培养物的顶孢霉菌株KR 21 -2，随后进行了单一或重复的处理实验，在Cr（NO3）3在pH 6.0。在有氧条件下，新形成的BMO表现出快速生产的Cr（VI），而没有显着释放的Mn（II），表明新形成的BMO介导的催化氧化的Cr（III）与自我再生步骤的减少锰。在厌氧溶液中，新形成的BMO显示出停止的Cr（III）的氧化在反应的早期阶段，随后有一个小得多的Cr（VI）的生产与显着释放的还原Mn（II）。非凡的螯合铬（III），观察在厌氧条件下的重复处理。厌氧螯合的Cr（III）很容易转化为Cr（VI）的条件时，成为有氧，这表明，表面钝化是负责厌氧停止Cr（III）氧化。本文提出的结果增加了我们对BMO在Cr（III）氧化和螯合过程中的作用的理解，在潜在的应用BMO对修复Cr（III）/Cr（VI）污染场地。
Biogenic manganese oxides (BMOs) have gained increasing attention for environmental application because of their sequestration and oxidizing abilities for various elements. Oxidation and sequestration of Cr(III) by BMOs, however, still remain unknown. We prepared BMOs in liquid cultures of Acremonium strictum strain KR21-2, and subsequently conducted single or repeated treatment experiments in Cr(NO3)3 at pH 6.0. Under aerobic conditions, newly formed BMOs exhibited a rapid production of Cr(VI) without a significant release of Mn(II), demonstrating that newly formed BMO mediates a catalytic oxidation of Cr(III) with a self-regeneration step of reduced Mn. In anaerobic solution, newly formed BMOs showed a cessation of Cr(III) oxidation in the early stage of the reaction, and subsequently had a much smaller Cr(VI) production with significant release of reduced Mn(II). Extraordinary sequestration of Cr(III) was observed during the repeated treatments under anaerobic conditions. Anaerobically sequestered Cr(III) was readily converted to Cr(VI) when the conditions became aerobic, which suggests that the surface passivation is responsible for the anaerobic cessation of Cr(III) oxidation. The results presented herein increase our understanding of the roles of BMO in Cr(III) oxidation and sequestration processes in potential application of BMOs towards the remediation of Cr(III)/Cr(VI) in contaminated sites.
影响因子：
8.8
作者：
Hu L;Cai Y;Jiang G
通讯作者：
Jiang G
影响因子：
11.4
作者：
Murray, Karen J.;Tebo, Bradley M.
通讯作者：
Tebo, Bradley M.