摘要

       在这项研究中，我们比较了在使用相同初级出水的两个废水处理系统中抗生素抗性细菌 (ARB) 和抗生素抗性基因 (ARG) 的去除情况：传统的废水处理系统（由滴滤器和活性污泥处理组成） ) 与基于藻类的系统相比，采用嗜极藻类 Galdieriasulfuraria。我们的结果表明，与传统处理系统相比，藻类系统可以更有效地降低废水中耐红霉素和磺胺甲恶唑细菌的浓度。在两个处理系统中都观察到总细菌和 ARGs 的下降趋势。然而，在常规系统中，存活细菌中大多数ARGs（qnrA、qnrB、qnrS、sul1）和intI1的相对比例增加；而藻类系统降低了存活细菌中qnrA、qnrS、tetW和intⅠ1的相对丰度。噬菌体在两个系统中 ARG 水平基因转移 (HGT) 中的作用通过噬菌体中 ARG 绝对丰度和细菌中 ARG 相对丰度之间的正相关来表明。五个可检测基因中的四个（qnrS、tetW、sul1 和 intI1）在噬菌体阶段的藻类系统中显着减少，这表明藻类系统中噬菌体介导的 ARG 转移减少。这项研究的结果证明了基于藻类的废水处理系统在减少 ARG 和 ARB 以及最大限度地减少抗生素耐药性对环境的传播方面的可行性。

       In this study, we compared removal of antibiotic resistant bacteria (ARB) and antibiotic resistant genes (ARGs) in two wastewater treatment systems fed with the same primary effluent: a conventional wastewater treatment system (consisting of a trickling filter followed by an activated sludge process) versus an algal-based system, employing an extremophilic alga, Galdieria sulphuraria. Our results demonstrated that the algal system can reduce concentrations of erythromycin- and sulfamethoxazole-resistant bacteria in the effluent more effectively than the conventional treatment system. A decreasing trend of total bacteria and ARGs was observed in both the treatment systems. However, the relative ratio of most ARGs (qnrA, qnrB, qnrS, sul1) and intI1 in the surviving bacteria increased in the conventional system; whereas, the algal system reduced more of the relative abundance of qnrA, qnrS, tetW and intⅠ1 in the surviving bacteria. The role of bacteriophages in horizontal gene transfer (HGT) of ARGs in the two systems was indicated by a positive correlation between ARG absolute abundance in bacteriophage and ARG relative abundance in the bacteria. Four of the five detectable genes (qnrS, tetW, sul1 and intI1) were significantly reduced in the algal system in bacteriophage phase which signified a decrease in phage-mediated ARG transfer in the algal system. Results of this study demonstrate the feasibility of the algal-based wastewater treatment system in decreasing ARGs and ARB and in minimizing the spread of antibiotic resistance to the environment.

https://www.sciencedirect.com/science/article/abs/pii/S0048969719344262