Low-dosage ozonation in gas-phase biofilter promotes community diversity and robustness

Abstract Background The ozonation of biofilters is known to alleviate clogging and pressure drop issues while maintaining removal performances in biofiltration systems treating gaseous volatile organic compounds (VOCs). effects ozone on the biofilter microbiome terms biodiversity, community structure, metabolic abilities, dominant taxa correlated with performance remain largely unknown. Methods This study investigated two high-concentration toluene operating parallel, one acting as control other exposed low-dosage (200 mg/m 3 ) ozonation. microbial diversity, rates different carbon sources, functional predictions, co-occurrence networks both communities were examined. Results Consistently higher biodiversity over 30% was observed after ozonation, increased overall abilities for amino acids carboxylic acids. relative abundance species reported stress-tolerant biofilm-forming significantly increased, a consortium changes predicted biological pathways, including shifts degradation pathways intermediate compounds, correlation top ASVs genus indicators showed diversifications microbiota responsible degradation. A network decrease average path distance betweenness Conclusion Major degrading highly shifted Increases coupled improvements metabolizing multiple sources could explain consistent commonly seen despite biomass, avoiding acid buildup long-term operation. presence microbes decentralization suggest that not only ameliorate but also provide more robust loading shock full-scale biofilters.