School of Environmental Science and Engineering, Institute of Environmental, Health and Pollution Control, Guangdong University of Technology, Guangzhou, 510006, PR China; Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, Southern University of Science and Technology, Shenzhen, 518055, China.
School of Environmental Science and Engineering, Institute of Environmental, Health and Pollution Control, Guangdong University of Technology, Guangzhou, 510006, PR China.
Chemosphere. 2021 Jun;272:129627. doi: 10.1016/j.chemosphere.2021.129627. Epub 2021 Jan 16.
Toxic metal ions were previously found to be effective removed by anodic biofilms under the coexistence of organics in bioelectrochemical system (BES). However, the effect of toxic metal ions on the organics fermentation pathways remains unclear. To investigate the pathway systematically, the glucose fermentation pathways were discussed under different Cu concentrations. After introducing Cu, more acetate and less propionate were observed, implying that the metabolic reaction of glucose fermentation altered from mixed acid type to acetogenesis type. This pattern produced more "food" (acetate or hydrogen) for methanogens, thus, the methane content increased by 19.67%, 39.51%, and 27.71% in the presence of 0.1, 1, and 7 mg L Cu compared to the blank, respectively. Increased Cu concentrations resulted in the decrease of current production, which was associated with the decrease of electricigen (Geobacter). Consistent with the change of fermentation type, the fermenters (Klebsiella and norank_f__norank_o__Bacteroidales) that related to the production of acetate increased, while the dominant methanogens (Methaospirillum) didn't decrease until the Cu concentration reached 7 mg L.
先前发现，在生物电化学系统（BES）中有机物共存的情况下，阳极生物膜可以有效去除有毒金属离子。然而，有毒金属离子对有机物发酵途径的影响尚不清楚。为了系统地研究这一途径，我们在不同的 Cu 浓度下讨论了葡萄糖发酵途径。引入 Cu 后，观察到更多的乙酸和更少的丙酸，这意味着葡萄糖发酵的代谢反应从混合酸型转变为产乙酸型。这种模式为产甲烷菌产生了更多的“食物”（乙酸或氢气），因此，与空白相比，在 0.1、1 和 7mg/L Cu 存在下，甲烷含量分别增加了 19.67%、39.51%和 27.71%。Cu 浓度的增加导致电流产生减少，这与电活性菌（Geobacter）的减少有关。与发酵类型的变化一致，与乙酸生成有关的发酵菌（Klebsiella 和 norank_f__norank_o__拟杆菌门）增加，而主要的产甲烷菌（Methaospirillum）直到 Cu 浓度达到 7mg/L 才减少。
