Abstract：
Bioelectrochemical systems (BES) offer significant potential for treating refractory waste and recovering bioenergy. However, their ability to mitigate microplastic pollution in wastewater remains unexplored. This study showed that BES facilitated the treatment of polyethylene (PE), polyvinyl chloride (PVC), and Mix (PE+PVC) microplastic wastewater and the methane recovery (40.61%, 20.02%, 21.19%, respectively). The lactate dehydrogenase (LDH), adenosine triphosphate (ATP), cytochrome c, and nicotinamide adenine dinucleotide (NADH/NAD+) ratios were elevated with electrical stimulation. Moreover, the applied voltage improved the polysaccharides content of the extracellular polymeric substances (EPS) in the PE-BES but decreased in PVC-BES, while the proteins showed the opposite trend. Metatranscriptomic sequencing showed that the abundance of fermentation bacteria, acetogens, electrogens, and methanogens was greatly enhanced by applying voltage, especially at the anode. Methane metabolism was dominated by the acetoclastic methanogenic pathway, with the applied voltage promoting the enrichment of Methanothrix, resulting in the direct conversion of acetate to acetyl-CoA via acetate-CoA ligase (EC: 6.2.1.1), and increased metabolic activity in the anode. Moreover, applied voltage greatly boosted the function genes expression level related to energy metabolism, tricarboxylic acid (TCA) cycle, electron transport, and transporters on the anode biofilm. Overall, these results demonstrate that BES can mitigate microplastic pollution during wastewater treatment.
摘要：
生物电化学系统（BES）为处理耐火废物和回收生物能源提供了巨大的潜力。然而,它们减轻废水中微塑料污染的能力仍未开发。这项研究表明，BES促进了聚乙烯（PE）的处理，聚氯乙烯(PVC),和混合(PE+PVC)微塑料废水和甲烷回收率(40.61%，20.02%,21.19%，分别)。乳酸脱氢酶（LDH），三磷酸腺苷（ATP），细胞色素c,和烟酰胺腺嘌呤二核苷酸(NADH/NAD+)比值随电刺激而升高。此外，施加电压提高了PE-BES中胞外聚合物（EPS）的多糖含量，但降低了PVC-BES中的多糖含量，而蛋白质则表现出相反的趋势。超转录组测序表明，发酵细菌的丰度，产乙酸原，电原,通过施加电压大大增强了产甲烷菌，尤其是在阳极。甲烷代谢主要由乙酰碎屑产甲烷途径控制，随着外加电压促进甲烷的富集，导致乙酸通过乙酸-CoA连接酶直接转化为乙酰-CoA（EC：6.2.1.1），并增加了阳极的代谢活性。此外，外加电压大大提高了与能量代谢相关的功能基因表达水平，三羧酸（TCA）循环，电子传输,和阳极生物膜上的转运蛋白。总的来说,这些结果表明，BES可以减轻污水处理过程中的微塑料污染。
