当前位置: X-MOL 学术Environ. Sci.: Nano › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Nano-Fe3O4 particles accelerating electromethanogenesis on an hour-long timescale in wetland soil†
Environmental Science: Nano ( IF 7.3 ) Pub Date : 2017-12-12 00:00:00 , DOI: 10.1039/c7en00577f
Leilei Xiao 1, 2, 3, 4, 5 , Fanghua Liu 1, 2, 3, 4, 5 , Jinchao Liu 1, 2, 3, 4, 5 , Jiajia Li 1, 2, 3, 4, 5 , Yuechao Zhang 1, 2, 3, 4, 5 , Jiafeng Yu 5, 6, 7, 8, 9 , Oumei Wang 5, 10, 11
Affiliation  

Electromethanogenesis, which is different from traditional hydrogenotrophic and acetoclastic methanogenesis, is a novel means of methane production involving the direct transfer of electrons to methanogens. Nano-Fe3O4 (nano-magnetite) has been found to strengthen the link between electricity-producing bacteria and methanogens; however, whether nano-Fe3O4 changes the carbon- and/or electron-flow pathways involved in the methanogenic processes in natural soil remains unknown. Experiments on wetland soil were reported in this work. Experimental results showed that nano-Fe3O4 particles significantly stimulated methane production. Combining the application of a stable isotope tracer (13CH3COOH) and an acetoclastic methanogenesis inhibitor (CH3F) and thermodynamic calculations, the results indicated that nano-Fe3O4 accelerated the CO2 reduction process rather than acetoclastic methanogenesis. Comprehensive utilization of a variety of methods (thermodynamic calculations, current density measurements, and model analysis) suggested that electrons, which came from syntrophic acetate oxidation (SAO), were the reducing agents for methane production. Nano-Fe3O4 did not appear to change the carbon flow but did promote electron transfer, and the whole process can be finished within an hour-long timescale. Furthermore, a dramatic increase in acetoclastic methanogenesis was observed within only 9 h incubation. This suggests that the methanogenic pathways are flexible and transitory in natural soil. Coupled with cDNA sequencing results for the active bacteria and archaea, it is suggested that SAO and electromethanogenesis were preferred when Geobacter and Methanosarcina were involved. These findings add to the knowledge of the role of nano-Fe3O4 in methanogenic processes in natural and artificial environments.

中文翻译:

纳米Fe 3 O 4颗粒在一个小时的时间内加速了湿地土壤中的甲烷生成过程†

不同于传统的氢营养型和乙酰碎屑的甲烷生成,电甲烷生成是甲烷生产的一种新颖方法,涉及将电子直接转移至甲烷生成素。纳米铁3 O 4(纳米磁铁矿)被发现可以加强产电细菌和产甲烷菌之间的联系。然而,纳米Fe 3 O 4是否会改变天然土壤甲烷化过程中涉及的碳和/或电子流动途径尚不清楚。在这项工作中报道了在湿地土壤上的实验。实验结果表明,纳米Fe 3 O 4颗粒显着促进了甲烷的产生。结合稳定同位素示踪剂的应用(13 CH 3 COOH)和一个破壳层甲烷生成抑制剂(CH 3 F)以及热力学计算结果表明,纳米Fe 3 O 4加速了CO 2还原过程,而不是破壳层甲烷生成。多种方法(热力学计算,电流密度测量和模型分析)的综合利用表明,合成乙酸乙酸酯(SAO)产生的电子是甲烷生成的还原剂。纳米铁3 O 4似乎并没有改变碳的流量,但确实促进了电子的转移,整个过程可以在一个小时的时间内完成。此外,仅在9 h的孵育过程中就观察到了破碎屑甲烷生成的显着增加。这表明产甲烷途径在天然土壤中是灵活的和短暂的。结合活性细菌和古细菌的cDNA测序结果,表明当涉及GeobacterMethanosarcina时,首选SAO和电甲烷生成。这些发现增加了对纳米Fe 3 O 4在自然和人工环境下产甲烷过程中作用的认识。
更新日期:2017-12-12
down
wechat
bug