School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, PR China; Hubei Provincial Engineering Laboratory of Solid Waste Treatment, Disposal and Recycling, 1037 Luoyu Road, Wuhan, Hubei, 430074, PR China.
School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, PR China; Hubei Provincial Engineering Laboratory of Solid Waste Treatment, Disposal and Recycling, 1037 Luoyu Road, Wuhan, Hubei, 430074, PR China.
Chemosphere. 2021 May;270:129455. doi: 10.1016/j.chemosphere.2020.129455. Epub 2020 Dec 29.
Microbial fuel cell (MFC) sensor exhibits attractive prospects for online monitoring of water toxicity as an early warning device. However, the accumulation of dead cells in anode biofilm might decrease the sensing sensitivity of MFC during long term operation. In addition, with repeated exposure to toxins, the microbial community of anode biofilm would also adjust to build up higher endurance to environmental toxicity. In this study, the long term sensing sensitivity of MFC sensor and the microbial community changes were characterized with Pb as the target toxin. The results show that newly formed biofilm with higher live/dead cell ratio exhibited higher sensitivity than mature biofilm. Modification of anodic biofilm via high current stimulation was applied to increase the ratio of live cells, which led to enhanced sensing sensitivity of MFC with mature anode biofilm. However, the enhancement was relatively limited for biofilm that was previously exposed to repeated Pb shocks. Microbial community analysis revealed that the proportions of microbial species possessing higher environmental robustness, such as Hyphomicrobiaceae and Cloacibacillus, significantly increased in the anode biofilm after long term repeated Pb shocks.
微生物燃料电池（MFC）传感器作为一种预警装置，在水体毒性的在线监测方面具有广阔的应用前景。然而，在长期运行过程中，阳极生物膜中死细胞的积累可能会降低 MFC 的传感灵敏度。此外，随着反复接触毒物，阳极生物膜中的微生物群落也会进行调整，以建立更高的环境毒性耐受能力。在这项研究中，以 Pb 作为目标毒素，研究了 MFC 传感器的长期传感灵敏度和微生物群落的变化。结果表明，具有更高活/死细胞比例的新形成生物膜表现出更高的灵敏度，而成熟生物膜的灵敏度较低。通过高电流刺激对阳极生物膜进行修饰，以增加活细胞的比例，从而提高了具有成熟阳极生物膜的 MFC 的传感灵敏度。然而，对于先前经历过多次 Pb 冲击的生物膜，这种增强效果相对有限。微生物群落分析表明，在长期重复 Pb 冲击后，具有更高环境鲁棒性的微生物种类（如 Hyphomicrobiaceae 和 Cloacibacillus）在阳极生物膜中的比例显著增加。
