School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore; Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, CleanTech One, 637141, Singapore.
Singapore Membrane Technology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, CleanTech One, 637141, Singapore.
Sci Total Environ. 2016 Aug 15;562:604-613. doi: 10.1016/j.scitotenv.2016.04.020. Epub 2016 Apr 22.
The potential toxicity of pharmaceutical residues including ibuprofen on the aquatic vertebrates and invertebrates has attracted growing attention to the pharmaceutical pollution control using constructed wetlands, but there lacks of an insight into the relevant microbial degradation mechanisms. This study investigated the bacteria associated with the cometabolic and metabolic degradation of ibuprofen in a horizontal subsurface flow constructed wetland system by high-throughput pyrosequencing analysis. The ibuprofen degradation dynamics, bacterial diversity and evenness, and bacterial community structure in a planted bed with Typha angustifolia and an unplanted bed (control) were compared. The results showed that the plants promoted the microbial degradation of ibuprofen, especially at the downstream zones of wetland. However, at the upstream one-third zone of wetland, the presence of plants did not significantly enhance ibuprofen degradation, probably due to the much greater contribution of cometabolic behaviors of certain non-ibuprofen-degrading microorganisms than that of the plants. By analyzing bacterial characteristics, we found that: (1) The aerobic species of family Flavobacteriaceae, family Methylococcaceae and genus Methylocystis, and the anaerobic species of family Spirochaetaceae and genus Clostridium_sensu_stricto were the most possible bacteria relevant to the cometabolic degradation of ibuprofen; (2) The family Rhodocyclaceae and the genus Ignavibacterium closely related to the plants appeared to be associated with the metabolic degradation of ibuprofen.
包括布洛芬在内的药物残留对水生脊椎动物和无脊椎动物的潜在毒性引起了人们对利用人工湿地控制药物污染的关注，但对相关微生物降解机制仍缺乏深入了解。本研究通过高通量焦磷酸测序分析，研究了水平潜流人工湿地系统中布洛芬共代谢和代谢降解相关的细菌。比较了种植香蒲（Typha angustifolia）和未种植（对照）床中布洛芬降解动力学、细菌多样性和均匀度以及细菌群落结构。结果表明，植物促进了布洛芬的微生物降解，尤其是在湿地的下游区。然而，在湿地的三分之一上游区，植物的存在并没有显著提高布洛芬的降解，这可能是由于某些非布洛芬降解微生物的共代谢行为的贡献大于植物的贡献。通过分析细菌特征，我们发现：（1）好氧的黄杆菌科、甲基球菌科和甲基胞菌属，以及厌氧的螺旋体科和严格梭菌属的种，是与布洛芬共代谢降解最相关的细菌；（2）与植物密切相关的红环菌科和 Ignavibacterium 属可能与布洛芬的代谢降解有关。
