Biodegradation of organic micropollutants across methanotrophic communities and environmental conditions

The biodegradation of organic micropollutants (OMPs) by microbial communities presents a sustainable solution for water treatment. This study evaluated the effects of adaptation to OMPs and operational parameters on the degradation of 14 compounds using methanotrophic enrichments from groundwater, wastewater inoculums, and mixed methanotrophic cultures derived from a lab-scale fermenter. Experiments tested pre-adapted and non-adapted microbial communities under varying solids retention times, copper levels, methane loading rates, oxygen-to-methane ratios, and nitrogen sources. Pre-adapted communities demonstrated enhanced degradation, with up to 70% removal of specific OMPs by the wastewater-derived inoculums. Copper addition improved degradation, likely via activation of the particulate methane monooxygenase (pMMO), despite literature suggesting the soluble methane monooxygenase (sMMO) as a primary catalyst for biodegradation. Throughout the tested cultures, stable dominance of genera such as Methylobacter and Sedimentibacterium indicated that variability in biokinetics was influenced by shifts in microbial activity or contributions from low-abundance taxa. These findings highlight the potential of pre-adapted microbial communities to enrich specialized degraders, improving OMP removal efficiency in water treatment systems.