醌-氧化石墨烯复合物协同促进双酚类化合物厌氧生物降解及机理研究

To improve anaerobic biodegradation rates of bisphenol compounds, in this project, bisphenol A is used as a target pollutant, a Fe(Ⅲ)-reducing strain capable of degrading bisphenol A is regarded as a model strain, anaerobic biodegradation characterization of bisphenol A by the strain and the synergistic accelerating effect of AQ-GO composite are investigated when 2-aminoanthraquinone-graphene oxide (AQ-GO) composite and Fe(Ⅲ) are used as a redox mediator and an electron acceptor, respectively. Moreover, the major degradation products are analyzed during bisphenol A biodegradation. Based on the above results, some functional proteins involved in ananerobic degradation of bisphenol A and AQ-GO composite reduction are analyzed using proteomics technologies. Combined the identified degradation products with the functional proteins during bisphenol A biodegradation, anaerobic degradation pathway of bisphenol A and the mechanism of the synergistic accelerating effect of AQ-GO composite are clarified. According to the above studies, the mechanism of the synergistic accelerating effect of AQ-GO composite on the anaerobic degradation rate of bisphenol A will be revealed in this project. This result will not only is beneficial to understand the environmental fate of bisphenol compounds under anaerobic conditions, but also provide the theory basis for anaerobic bioremediation of bisphenol compounds.

为提高双酚类化合物的厌氧生物降解速率，本项目以双酚A为目标污染物，以2-氨基蒽醌-氧化石墨烯（AQ-GO）复合物为氧化还原介体，以Fe(Ⅲ)为电子受体，以一株具有降解双酚A能力的Fe(Ⅲ)还原菌为模式菌株，研究双酚A的厌氧生物降解特性及AQ-GO复合物的协同促进作用，分析双酚A的主要降解产物。在此基础上，采用微生物蛋白质组学技术解析参与双酚A厌氧降解和AQ-GO复合物还原的功能蛋白质，并结合双酚A的主要降解产物，阐明双酚A厌氧降解途径及AQ-GO复合物协同作用机理。通过上述研究，本项目将揭示AQ-GO复合物协同促进双酚类化合物厌氧生物降解机理。这不仅有助于理解双酚类化合物在厌氧环境中的归趋，并且为双酚类化合物厌氧生物修复提供一定的理论基础。

为提高双酚类化合物的厌氧生物转化速率，本项目以双酚A的替代品双酚F为目标污染物，以2-氨基蒽醌-氧化石墨烯（AQ-GO）复合物为氧化还原介体，以硝酸盐为电子受体，以一株具有厌氧转化双酚F能力的硝酸盐还原菌假单胞菌株HS-2为模式菌株，研究双酚F的厌氧生物转化特性及AQ-GO复合物的协同促进作用机理。研究结果表明，在以5 mM硝酸盐为电子受体，pH为7和温度35℃条件下，假单胞菌株HS-2能够将双酚F转化为4,4-二羟基二苯基甲酮。外加碳源不能够促进双酚F的厌氧生物转化。2-氨基蒽醌（AQ）和氧化石墨烯（GO）能够加速双酚F的厌氧生物转化速率。AQ-GO复合材料中AQ与GO的质量比为1:4时，对20mg/L BPF厌氧转化促进效果最好。当AQ-GO浓度为30mg/L时，促进作用比不加AQ-GO材料提高了3.1倍。进一步研究发现，当AQ-GO浓度为15mg/L时，其促进作用大于AQ与GO单独作用之和，即AQ与GO之间协同作用的发生。采用基因组学和转录组学技术，揭示了AQ和GO加速双酚F厌氧生物转化的过程：首先，双酚F在脱氢酶作用下转化为DHBP，并将电子传递给NAD(P)+，NAD(P)+在还原酶作用下生成NAD(P)H，然后通过依赖于NAD(P)H的多种醌还原酶，将电子传递给AQ或者GO；最后还原后的AQDS（氢醌）和GO可将电子通过硝酸盐还原酶给硝酸盐，使硝酸盐还原为亚硝酸盐。上述研究结果不仅有助于理解双酚类化合物在厌氧环境中的归趋，并且为双酚类化合物厌氧生物修复提供一定的理论基础。