Zhou Mi, Liu Guang-Fei, Zhou Ji-Ti, Jin Ruo-Fei, Chen Ming-Xiang, Wang Yan-Qing
Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental and Biological Science and Technology, Dalian University of Technology, Dalian 116024, China.
Huan Jing Ke Xue. 2009 Jun 15;30(6):1810-7.
Using quinoid redox mediator and bacterial cellular quinone reductase, we investigated the decolorization ability of gene-engineered strain Escherichia coli YB and the effects of methylhydroquinone (MHQ) pretreatement on decolorization performance of E. coli JM109 and anaerobic sludge. The results indicate that lawsone is an effective accelerator for azo dye decolorization by E. coli YB overexpressing cellular quinone reductase AZR. In the presence of 0.2 mmol x L(-1) lawsone, 75% Amaranth (1 mmol x L(-1)) can be decolorized in 2 h. E. coli YB can also decolorize high concentration of azo dye in the presence of lawsone. Around 50% Amaranth (5 mmol x L(-1)) is decolorized in 8 h. Compared to lawsone, menadione is a less effective mediator. E. coli YB takes 12 h to reach 70% decolorization in the presence of 2.5 mmol x L(-1) menadione. Repeated decolorization studies showed that E. coli YB had stable decolorizing ability in the presence of lawsone. Four rounds of repeated decolorization can be completed in 12 h. Lawsone can also accelerate the decolorization of azo dyes with complex structures such as Acid Scarlet GR and Reactive Brilliant Red K-2BP. With the optimal LQ concentrations, 70% Acid Scarlet GR and Reactive Brilliant Red K-2BP are decolorized in 9 h and 30 h,respectively. Decolorization performances of E. coli JM109 and anaerobic sludge pretreated with MHQ are improved. After MHQ pretreatment,in the presence of lawsone, 80% Amaranth (1 mmol x L(-1)) can be decolorized in 5 h by E. coli JM109, while more than 75% Amaranth can be removed in 11 h by sludge.
利用醌类氧化还原介质和细菌细胞醌还原酶，我们研究了基因工程菌株大肠杆菌YB的脱色能力，以及甲基对苯二酚（MHQ）预处理对大肠杆菌JM109和厌氧污泥脱色性能的影响。结果表明，胡桃醌是过表达细胞醌还原酶AZR的大肠杆菌YB对偶氮染料脱色的有效促进剂。在存在0.2 mmol·L⁻¹胡桃醌的情况下，75%的苋菜红（1 mmol·L⁻¹）可在2小时内脱色。在存在胡桃醌的情况下，大肠杆菌YB也能对高浓度偶氮染料进行脱色。约50%的苋菜红（5 mmol·L⁻¹）在8小时内脱色。与胡桃醌相比，甲萘醌是一种效果较差的介质。在存在2.5 mmol·L⁻¹甲萘醌的情况下，大肠杆菌YB需要12小时才能达到70%的脱色率。重复脱色研究表明，在存在胡桃醌的情况下，大肠杆菌YB具有稳定的脱色能力。12小时内可完成四轮重复脱色。胡桃醌还能加速结构复杂的偶氮染料如酸性大红GR和活性艳红K-2BP的脱色。在最佳LQ浓度下，70%的酸性大红GR和活性艳红K-2BP分别在9小时和30小时内脱色。经MHQ预处理的大肠杆菌JM109和厌氧污泥的脱色性能得到改善。经MHQ预处理后，在存在胡桃醌的情况下，大肠杆菌JM109在5小时内可使80%的苋菜红（1 mmol·L⁻¹）脱色，而污泥在11小时内可去除75%以上的苋菜红。
