Enrichment and characterization of microbial consortium XY04 with high phenol tolerance and biodegradation capacity

AIMS: This study aims to obtain a highly efficient and tolerant microbial community for the treatment of high-concentration phenolic and formaldehyde wastewater and analyze its community response mechanisms to high-concentration pollution. METHODS AND RESULTS: Using acclimation techniques, we developed microbial consortium XY04, capable of degrading up to 3000 mg L-1 phenol and 2000 mg L-1 formaldehyde. XY04 degraded 1500 mg L-1 phenol within 24 h (62.5 mg L-1·h-1) and 1500 mg L-1 formaldehyde within 12 h (125 mg L-1·h-1). The consortium maintained high degradation efficiency across a wide range of conditions (pH 3-9, salinity 0%-3%, 20-35°C), and retained activity under extreme conditions (5% salinity, pH 11). Substrate spectrum analysis showed metabolic capacity for phenols, aldehydes, and aromatic hydrocarbons, with enhanced degradation efficiency from moderate carbon source supplementation. Community analysis revealed compositional shifts under high- and low-concentration conditions, with functional prediction indicating enhanced genes for phenol meta-cleavage and carbon, amino acid, and lipid metabolism under stress. ASV (amplicon sequence variant)-function coupling analysis showed that amplicon sequence variants enriched in high-concentration environments contributed to these pathways, suggesting community restructuring for stress adaptation. CONCLUSIONS: A highly efficient microbial consortium XY04 was obtained for phenolic and formaldehyde wastewater treatment, exhibiting tolerance to various environmental conditions and the ability to adapt to high-concentration pollution through community self-organization.