Burch Tucker R, Sadowsky Michael J, LaPara Timothy M
Department of Civil, Environmental, and Geo-Engineering, University of Minnesota, 500 Pillsbury Drive SE, Minneapolis, MN, 55455, USA.
Biotechnology Institute, University of Minnesota, St. Paul, MN, 55108, USA.
Appl Microbiol Biotechnol. 2016 Feb;100(3):1437-1444. doi: 10.1007/s00253-015-7043-x. Epub 2015 Oct 19.
This study investigated the use of thermophilic anaerobic digestion for removing antibiotic resistance genes (ARGs) from residual municipal wastewater solids. Four laboratory-scale anaerobic digesters were operated in 8-day batch cycles at temperatures of 40, 56, 60, and 63 °C. Two tetracycline resistance genes (tet(W) and tet(X)), a fluoroquinolone resistance gene (qnrA), the integrase gene of class 1 integrons (intI1), 16S rRNA genes of all Bacteria, and 16S rRNA genes of methanogens were quantified using real-time quantitative PCR. ARG and intI1 quantities decreased at all temperatures and were described well by a modified form of the Collins-Selleck disinfection kinetic model. The magnitudes of Collins-Selleck kinetic parameters were significantly greater at thermophilic temperatures compared to 40 °C, but few statistically significant differences were observed among these parameters for the thermophilic anaerobic digesters. This model allows for the direct comparison of different operating conditions (e.g., temperature) on anaerobic digestion performance in mitigating the quantity of ARGs in wastewater solids and could be used to design full-scale anaerobic digesters to specifically treat for ARGs as a "pollutant" of concern.
本研究调查了利用嗜热厌氧消化去除城市污水剩余污泥中抗生素抗性基因(ARGs)的情况。四个实验室规模的厌氧消化器在40、56、60和63℃的温度下以8天的批次循环运行。使用实时定量PCR对两个四环素抗性基因(tet(W)和tet(X))、一个氟喹诺酮抗性基因(qnrA)、1类整合子的整合酶基因(intI1)、所有细菌的16S rRNA基因以及产甲烷菌的16S rRNA基因进行了定量分析。在所有温度下,ARG和intI1的数量均有所下降,并且通过改进形式的柯林斯 - 塞莱克消毒动力学模型能够很好地描述这种下降情况。与40℃相比,嗜热温度下柯林斯 - 塞莱克动力学参数的幅度显著更大,但对于嗜热厌氧消化器而言,这些参数之间几乎没有观察到统计学上的显著差异。该模型能够直接比较不同运行条件(如温度)对厌氧消化性能的影响,以减轻污水污泥中ARGs的数量,并且可用于设计全规模厌氧消化器,专门针对作为关注“污染物”的ARGs进行处理。