Department of Earth and Environmental Sciences, Indian Institute of Science Education and Research Mohali (IISER Mohali), Sector 81, S.A.S. Nagar, Manauli PO 140306, Punjab, India.
Department of Earth and Environmental Sciences, Indian Institute of Science Education and Research Mohali (IISER Mohali), Sector 81, S.A.S. Nagar, Manauli PO 140306, Punjab, India.
Bioresour Technol. 2021 Jan;320(Pt A):124289. doi: 10.1016/j.biortech.2020.124289. Epub 2020 Oct 21.
The present study aimed to demonstrate the utilization of unpurified industrial CO with low impurities for acetate production via microbial electrosynthesis (MES) for the first time. In MES experiments with CO-rich brewery gas, the enriched mixed culture dominated by Acetobacterium produced 1.8 ± 0.2 g/L acetic acid at 0.26 ± 0.03 g/L/d rate and outperformed a pure culture of Clostridium ljungdahlii (1.1 ± 0.02 g/L; 0.138 ± 0.004 g/L/d). The electron recovery in acetic acid was also more for mixed culture (84 ± 13%) than C. ljungdahlii (42 ± 14%). Electrochemical analysis of biocathodes suggested the role of microbial biofilm in improved hydrogen electrocatalysis. In comparative gas fermentation tests, the mixed culture outperformed C. ljungdahlii and produced acetic acid at a similar level with both industrial and pure CO feedstocks. These results suggest the robustness and capability of the mixed microbial community for utilizing slightly impure industrial CO for bioproduction and presents a major advancement in MES technology.
本研究首次展示了未经纯化的低杂质工业 CO 在微生物电解合成（MES）中用于生产乙酸的应用。在以富含 CO 的啤酒厂废气为底物的 MES 实验中，以醋杆菌属为主的富混合培养物以 0.26 ± 0.03 g/L/d 的速率生产了 1.8 ± 0.2 g/L 的乙酸，优于纯培养的丙酮丁醇梭菌（1.1 ± 0.02 g/L；0.138 ± 0.004 g/L/d）。混合培养物的乙酸电子回收率也更高（84 ± 13%），而丙酮丁醇梭菌为 42 ± 14%。生物阴极的电化学分析表明微生物生物膜在提高氢气电催化方面发挥了作用。在比较气体发酵试验中，混合培养物优于丙酮丁醇梭菌，并且使用工业和纯 CO 两种原料生产乙酸的水平相似。这些结果表明混合微生物群落具有利用略微不纯的工业 CO 进行生物生产的稳健性和能力，代表了 MES 技术的重大进展。
