{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"submitter":["Ha BN"],"funding":["the Carbon Recycle Fund","Iwatani Naoji Foundation","the Institute of Fermentation, Osaka","Japan Society for the Promotion of Science"],"pagination":["2546"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC8909181"],"repository":["biostudies-literature"],"omics_type":["Unknown"],"volume":["19(5)"],"pubmed_abstract":["Acetogenesis and methanogenesis have attracted attention as CO<sub>2</sub>-fixing reactions. Humin, a humic substance insoluble at any pH, has been found to assist CO<sub>2</sub>-fixing acetogenesis as the sole electron donor. Here, using two CO<sub>2</sub>-fixing consortia with acetogenic and methanogenic activities, the effect of various parameters on these activities was examined. One consortium utilized humin and hydrogen (H<sub>2</sub>) as electron donors for acetogenesis, either separately or simultaneously, but with a preference for the electron use from humin. The acetogenic activity was accelerated 14 times by FeS at 0.2 g/L as the optimal concentration, while being inhibited by MgSO<sub>4</sub> at concentration above 0.02 g/L and by NaCl at concentrations higher than 6 g/L. Another consortium did not utilize humin but H<sub>2</sub> as electron donor, suggesting that humin was not a universal electron donor for acetogenesis. For methanogenesis, both consortia did not utilize extracellular electrons from humin unless H<sub>2</sub> was present. The methanogenesis was promoted by FeS at 0.2 g/L or higher concentrations, especially without humin, and with NaCl at 2 g/L or higher concentrations regardless of the presence of humin, while no significant effect was observed with MgSO<sub>4</sub>. Comparative sequence analysis of partial 16S rRNA genes suggested that minor groups were the humin-utilizing acetogens in the consortium dominated by <i>Clostridia</i>, while <i>Methanobacterium</i> was the methanogen utilizing humin with H<sub>2</sub>."],"journal":["International journal of environmental research and public health"],"pubmed_title":["Effect of Humin and Chemical Factors on CO<sub>2</sub>-Fixing Acetogenesis and Methanogenesis."],"pmcid":["PMC8909181"],"funding_grant_id":["20H04363, 20K15431, 21K19862","2020 Research Project","2020 research project","L-2019-003"],"pubmed_authors":["Ha BN","Kasai T","Pham DM","Katayama A","Awata T"],"additional_accession":[]},"is_claimable":false,"name":"Effect of Humin and Chemical Factors on CO<sub>2</sub>-Fixing Acetogenesis and Methanogenesis.","description":"Acetogenesis and methanogenesis have attracted attention as CO<sub>2</sub>-fixing reactions. Humin, a humic substance insoluble at any pH, has been found to assist CO<sub>2</sub>-fixing acetogenesis as the sole electron donor. Here, using two CO<sub>2</sub>-fixing consortia with acetogenic and methanogenic activities, the effect of various parameters on these activities was examined. One consortium utilized humin and hydrogen (H<sub>2</sub>) as electron donors for acetogenesis, either separately or simultaneously, but with a preference for the electron use from humin. The acetogenic activity was accelerated 14 times by FeS at 0.2 g/L as the optimal concentration, while being inhibited by MgSO<sub>4</sub> at concentration above 0.02 g/L and by NaCl at concentrations higher than 6 g/L. Another consortium did not utilize humin but H<sub>2</sub> as electron donor, suggesting that humin was not a universal electron donor for acetogenesis. For methanogenesis, both consortia did not utilize extracellular electrons from humin unless H<sub>2</sub> was present. The methanogenesis was promoted by FeS at 0.2 g/L or higher concentrations, especially without humin, and with NaCl at 2 g/L or higher concentrations regardless of the presence of humin, while no significant effect was observed with MgSO<sub>4</sub>. Comparative sequence analysis of partial 16S rRNA genes suggested that minor groups were the humin-utilizing acetogens in the consortium dominated by <i>Clostridia</i>, while <i>Methanobacterium</i> was the methanogen utilizing humin with H<sub>2</sub>.","dates":{"release":"2022-01-01T00:00:00Z","publication":"2022 Feb","modification":"2025-08-23T03:08:55.352Z","creation":"2025-04-04T13:21:55.619Z"},"accession":"S-EPMC8909181","cross_references":{"pubmed":["35270239"],"doi":["10.3390/ijerph19052546"]}}