Enhanced biodegradation of sulfamethazine in swine manure composting: Pathway elucidation, mechanism insights, and optimization of a novel Bacillus sp. strain

作者：Xiaojun Lin, Jingtong Li, Chunyan Chen, Zifeng Luo, Hongxing Tu, Yuwan Pang, Xiujuan Wang, Qianyi Cai, Zebin Wei, Jianfeng Huang, Jingwen Zeng, Jinrong Qiu · 发表于：International Biodeterioration & Biodegradation · 年份：2025 · DOI：10.1016/j.ibiod.2025.106112 · 被引用次数：2 · 研究领域：Pharmaceutical and Antibiotic Environmental Impacts、Analytical chemistry methods development、Water Treatment and Disinfection

Sulfamethazine (SMZ), a widely used sulfonamide antibiotic frequently detected in livestock waste streams, requires enhanced microbial degradation strategies to prevent its accumulation and associated environmental hazards. While several microbial strains with SMZ degradation capability have been isolated, comprehensive elucidation of metabolic pathways remains incomplete. This study identified Bacillus sp. strain DLY-11, exhibiting exceptional SMZ degradation performance, from thermally treated swine manure compost substrates. Under optimized parameters (5 % (v/v) bacterial inoculum, 59.7 °C operational temperature, pH 8.08 maintained with buffer system, and 0.4 g/L MgSO 4 supplementation), the strain achieved 97.1 % elimination of 20 mg/L SMZ within 48-h incubation. Metabolic pathway analysis through detected intermediates revealed two distinct biodegradation mechanisms involving sulfonamide bond cleavage, oxidative hydroxylation, sulfur dioxide elimination, ring oxidation, amino group substitution, and glucuronic acid conjugation. These findings enhance understanding of sulfonamide antibiotic catabolism while offering a promising microbial resource for controlling veterinary antibiotic contamination in agro-industrial ecosystems.