Tyszkiewicz Natalia, Truu Jaak, Młynarz Piotr, Pasternak Grzegorz
Laboratory of Microbial Electrochemical Systems, Department of Process Engineering and Technology of Polymer and Carbon Materials, Faculty of Chemistry, Wrocław University of Science and Technology, Wrocław, Poland.
Department of Biochemistry, Molecular Biology and Biotechnology, Faculty of Chemistry, Wrocław University of Science and Technology, Wrocław, Poland.
Front Microbiol. 2024 Jul 15;15:1384463. doi: 10.3389/fmicb.2024.1384463. eCollection 2024.
Bioelectrochemical systems offer unique opportunities to remove recalcitrant environmental pollutants in a net positive energy process, although it remains challenging because of the toxic character of such compounds. In this study, microbial fuel cell (MFC) technology was applied to investigate the benzene degradation process for more than 160 days, where glucose was used as a co-metabolite and a control. We have applied an inoculation strategy that led to the development of 10 individual microbial communities. The electrochemical dynamics of MFC efficiency was observed, along with their H NMR metabolic fingerprints and analysis of the microbial community. The highest power density of 120 mW/m was recorded in the final period of the experiment when benzene/glucose was used as fuel. This is the highest value reported in a benzene/co-substrate system. Metabolite analysis confirmed the full removal of benzene, while the dominance of fermentation products indicated the strong occurrence of non-electrogenic reactions. Based on 16S rRNA gene amplicon sequencing, bacterial community analysis revealed several petroleum-degrading microorganisms, electroactive species and biosurfactant producers. The dominant species were recognised as and . Strong, positive impact of the presence of benzene on the alpha diversity was recorded, underlining the high complexity of the bioelectrochemically supported degradation of petroleum compounds. This study reveals the importance of supporting the bioelectrochemical degradation process with auxiliary substrates and inoculation strategies that allow the communities to reach sufficient diversity to improve the power output and degradation efficiency in MFCs beyond the previously known limits. This study, for the first time, provides an outlook on the syntrophic activity of biosurfactant producers and petroleum degraders towards the efficient removal and conversion of recalcitrant hydrophobic compounds into electricity in MFCs.
生物电化学系统为在净正能量过程中去除难降解环境污染物提供了独特的机会，尽管由于此类化合物的毒性特征，这仍然具有挑战性。在本研究中，应用微生物燃料电池（MFC）技术对苯的降解过程进行了160多天的研究，其中葡萄糖用作共代谢物和对照。我们采用了一种接种策略，导致10个独立微生物群落的发展。观察了MFC效率的电化学动力学，以及它们的1H NMR代谢指纹图谱和微生物群落分析。当使用苯/葡萄糖作为燃料时，在实验的最后阶段记录到最高功率密度为120 mW/m²。这是苯/共底物系统中报道的最高值。代谢物分析证实苯被完全去除，而发酵产物的优势表明非产电反应强烈发生。基于16S rRNA基因扩增子测序，细菌群落分析揭示了几种石油降解微生物、电活性物种和生物表面活性剂生产者。优势物种被鉴定为 和 。记录到苯的存在对α多样性有强烈的积极影响，突出了生物电化学支持的石油化合物降解的高度复杂性。本研究揭示了用辅助底物和接种策略支持生物电化学降解过程的重要性，这些策略使群落能够达到足够的多样性，以提高MFC中的功率输出和降解效率，超越先前已知的极限。本研究首次展望了生物表面活性剂生产者和石油降解者在MFC中对难降解疏水性化合物进行有效去除和转化为电能的互营活性。
