Wang Yangyang, Li Fangfang, Ruan Xinling, Song Jian, Lv Lv, Chai Liyuan, Yang Zhihui, Luo Lin
School of Resources and Environment, Hunan Agricultural University, Changsha, China.
Key Research Institute of Yellow River Civilization and Sustainable Development & Collaborative Innovation Center on Yellow River Civilization of Henan Province, Henan University, Kaifeng, China.
PLoS One. 2017 May 25;12(5):e0178213. doi: 10.1371/journal.pone.0178213. eCollection 2017.
A stable bacterial consortium (LV-1) capable of degrading di-n-butyl phthalate (DBP) was enriched from river sludge. Community analysis revealed that the main families of LV-1 are Brucellaceae (62.78%) and Sinobacteraceae (14.83%), and the main genera of LV-1 are Brucella spp. (62.78%) and Sinobacter spp. (14.83%). The optimal pH and temperature for LV-1 to degrade DBP were pH 6.0 and 30°C, respectively. Inoculum size influenced the degradation ratio when the incubation time was < 24 h. The initial concentration of DBP also influenced the degradation rates of DBP by LV-1, and the degradation rates ranged from 69.0-775.0 mg/l/d in the first 24 h. Degradation of DBP was best fitted by first-order kinetics when the initial concentration was < 300 mg/l. In addition, Cd2+, Cr6+, and Zn2+ inhibited DBP degradation by LV-1 at all considered concentrations, but low concentrations of Pb2+, Cu2+, and Mn2+ enhanced DBP degradation. The main intermediates (mono-ethyl phthalate [MEP], mono-butyl phthalate [MBP], and phthalic acid [PA]) were identified in the DBP degradation process, thus a new biochemical pathway of DBP degradation is proposed. Furthermore, LV-1 also degraded other phthalates with shorter ester chains (DMP, DEP, and PA).
从河流污泥中富集得到了一个能够降解邻苯二甲酸二丁酯(DBP)的稳定细菌群落(LV-1)。群落分析表明,LV-1的主要菌科为布鲁氏菌科(62.78%)和中华杆菌科(14.83%),主要菌属为布鲁氏菌属(62.78%)和中华杆菌属(14.83%)。LV-1降解DBP的最适pH值和温度分别为pH 6.0和30℃。当培养时间<24 h时,接种量会影响降解率。DBP的初始浓度也会影响LV-1对DBP的降解速率,在前24 h内降解速率范围为69.0 - 775.0 mg/l/d。当初始浓度<300 mg/l时,DBP的降解最符合一级动力学。此外,在所有考虑的浓度下,Cd2+、Cr6+和Zn2+均抑制LV-1对DBP的降解,但低浓度的Pb2+、Cu2+和Mn2+会增强DBP的降解。在DBP降解过程中鉴定出了主要中间产物(邻苯二甲酸单乙酯[MEP]、邻苯二甲酸单丁酯[MBP]和邻苯二甲酸[PA]),因此提出了一条新的DBP降解生化途径。此外,LV-1还能降解其他酯链较短的邻苯二甲酸酯(DMP、DEP和PA)。