Shao Pengfei, Yao Jun, Li Miaomiao, Min Ning
School of Water Resources and Environment, Research Center of Environmental Science and Engineering, China University of Geosciences (Beijing), 29 Xueyuan Road, Haidian District, Beijing, 100083, China.
Biodegradation. 2025 Jul 22;36(4):67. doi: 10.1007/s10532-025-10159-9.
Phthalate esters (PAEs) are widely used as plasticizers and beneficiation flotation agents in ore smelters, which are ubiquitously distributed emerging contaminants in the environment. The biodegradation of PAEs by degrading microbes is a promising method for their remediation. In this study, we isolated a novel PAE-degrading bacteria, Sinomonas sp. S2, from a contaminated area of a metal(loid) smelter in Guangxi Zhuang Autonomous Region, China. Strain S2 is capable of degrading short-chain PAEs, including dimethyl phthalate (DMP), diethyl phthalate (DEP), di-iso-butyl phthalate (DIBP) and di-n-butyl phthalate (DBP). Sinomonas sp. S2 can completely degrade DBP at concentrations of 400 mg·L within 24 h. The degradation kinetics of PAEs followed the modified Gompertz model. Strain S2 demonstrated good environmental adaptability thriving at pH ranging from 5 to 9 and temperatures between 20 and 40 °C, indicated by its growth on DBP. The optimal pH and temperature for degradation were found to be 7 and 40 °C, respectively. Additionally, several metabolites of DBP were identified, including phthalic acid (PA), butyl acetate, ethyl propionate and methyl 2-methylbutyrate. The reconstructed degradation pathway of DBP may involve protocatechuic acid, β-carboxy-cis, cis-mucronate and γ-carboxy muconolactone, ultimately leading to the tricarboxylic acid (TCA). In a bioaugmentation experiment involving soil artificially contaminated with DBP, strain S2 could promote the degradation of DBP in soil. The results indicate that strain S2 had high degradation capacity and environmental tolerance, which had the potential to be applied in the bioremediation of DBP-contaminated environments.
邻苯二甲酸酯（PAEs）作为增塑剂和选矿浮选剂在矿石冶炼厂中被广泛使用，是环境中普遍存在的新兴污染物。通过降解微生物对PAEs进行生物降解是一种很有前景的修复方法。在本研究中，我们从中国广西壮族自治区某金属（类金属）冶炼厂的污染区域分离出一株新型PAE降解细菌——中华单胞菌属菌株S2。菌株S2能够降解短链PAEs，包括邻苯二甲酸二甲酯（DMP）、邻苯二甲酸二乙酯（DEP）、邻苯二甲酸二异丁酯（DIBP）和邻苯二甲酸二正丁酯（DBP）。中华单胞菌属菌株S2能够在24小时内完全降解浓度为400 mg·L的DBP。PAEs的降解动力学符合修正的Gompertz模型。菌株S2在pH值为5至9、温度为20至40°C的环境中生长良好，表现出良好的环境适应性，其在DBP上的生长情况表明了这一点。发现降解的最佳pH值和温度分别为7和40°C。此外，还鉴定出了DBP的几种代谢产物，包括邻苯二甲酸（PA）、乙酸丁酯、丙酸乙酯和2-甲基丁酸甲酯。重建的DBP降解途径可能涉及原儿茶酸、β-羧基-顺，顺-粘康酸和γ-羧基粘康内酯，最终通向三羧酸（TCA）循环。在一项涉及人工受DBP污染土壤的生物强化实验中，菌株S2能够促进土壤中DBP的降解。结果表明，菌株S2具有较高的降解能力和环境耐受性，具有应用于DBP污染环境生物修复的潜力。
