Effect of copper ions on glucose fermentation pathways in bioelectrochemical system. (June 2021)

• Record Type: Journal Article
• Authors: Zhang, Yaping; Xu, Yangao; Chen, Xi; Chen, Caiyun; Sun, Jian; Bai, Xiaoyan; Yuan, Yong
• Is Part Of: Chemosphere. Volume 272(2021)
• Publication Date: 2021-06
• Subjects: Toxic metals -- Glucose fermentation pathways -- Microbial community -- Anodic biofilms; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2021.129627
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: Toxic metal ions were previously found to be effective removed by anodic biofilms under the coexistence of organics in bioelectrochemical system (BES). However, the effect of toxic metal ions on the organics fermentation pathways remains unclear. To investigate the pathway systematically, the glucose fermentation pathways were discussed under different Cu 2+ concentrations. After introducing Cu 2+, more acetate and less propionate were observed, implying that the metabolic reaction of glucose fermentation altered from mixed acid type to acetogenesis type. This pattern produced more "food" (acetate or hydrogen) for methanogens, thus, the methane content increased by 19.67%, 39.51%, and 27.71% in the presence of 0.1, 1, and 7 mg L −1 Cu 2+ compared to the blank, respectively. Increased Cu 2+ concentrations resulted in the decrease of current production, which was associated with the decrease of electricigen ( Geobacter ). Consistent with the change of fermentation type, the fermenters ( Klebsiella and norank_f__norank_o__Bacteroidales ) that related to the production of acetate increased, while the dominant methanogens ( Methaospirillum ) didn't decrease until the Cu 2+ concentration reached 7 mg L −1 . Graphical abstract: Image 1 Highlights: Changes in fermentation products, electrical output, and methane generation were discussed. The glucose fermentation pathways were strongly influenced by Cu 2+ addition. The metabolic reaction of glucose fermentation altered from mixed acid type to acetogenesis type. The flow of electrons from acetate to anode decreased with increase of Cu 2+ concentration. A decrease in electricigens accompanied by an increase in fermenters was observed.