Biodegradation of 17β‐estradiol by drug‐resistant Stenotrophomonas maltophilia MN08 and Pseudomonas aeruginosa KL10 isolated from the sediment sample

Abstract

Abstract17 β‐Estradiol is produced by animals, and humans and excreted through excreta, and has endocrine‐disrupting activity. Bacterial degradation is one of the suitable methods used for the removal of 17 β‐estradiol (E2) from the natural environment. In this study, E2‐degrading bacteria were screened from the enriched sediment sample from the wastewater environment. Two bacterial strains of E2‐degrading bacteria (Stenotrophomonas maltophilia MN08 and Pseudomonas aeruginosa KL10) were determined and >70% of E2‐degradation was achieved. The strain MN08 could rapidly remove approximately 86.5% ± 1.3% of E2 within 7 days of treatment. In addition, the strain KL10 removed 79.5% ± 1% of E2 within the same period. Optimized culture temperature and pH of the medium could improve E2‐degradation. The results demonstrated that the strain MN08 exhibited maximum E2‐degradation activity at 35°C, and pH 8.0. The optimal pH for strain KL10 to degrade E2 ranged from 7.0 to 9.0. The E2‐degradation level for the mixture culture systems can exhibit synergistic E2‐degradation activity. The degradation of the MN08 and KL10 individual strains was 87.3% ± 1.2% and 81.4% ± 1.5%, respectively. The E2‐degradation potential for the mixed culture system was 91.3% ± 2.9% under optimized conditions in which 100 mg/L of E2 served as the sole source of carbon and energy. The present finding demonstrates that the co‐culture of S. maltophilia MN08 and P. aeruginosa KL10 may provide a promising bio‐treatment strategy for the removal of steroids from wastewater.