Ma Xiao-Kui, Li Ting-Ting, Fam Hala, Charles Peterson Eric, Zhao Wei-Wei, Guo Wenying, Zhou Bo
a Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry, Ministry of Education, National Engineering Laboratory for Resource Developing of Endangered Chinese Crude Drugs in Northwest of China, College of Life Science, Shaanxi Normal University , Xi'an , Shaanxi , People's Republic of China.
b Department of Chemical Engineering , Queen's University , Kingston , ON , Canada.
Environ Technol. 2018 Aug;39(16):2128-2137. doi: 10.1080/09593330.2017.1351492. Epub 2017 Jul 16.
Co-contamination of polycyclic aromatic hydrocarbons (PAHs) with heavy metals (HMs) in aquatic environments is a global threat; however, little is understood about PAH biodegradation in these sites. In this study, PAHs' biodegradation in the presence of HMs in water by a metal-tolerant consortium composed of Bacillus subtilis and fungus Acremonium sp. was investigated. The consortium demonstrated higher tolerance to the tested HMs (Fe, Al, Ni, Cu, Mn and Zn) than the individual consortium components, and the tolerance to individual metals decreased with increasing metal concentrations. In the absence of HMs in aquatic systems, the consortium efficiently degraded naphthalene, fluorine, phenanthrene, anthracene and fluoranthene individually (50 mmol/L) over 10 days. However, while Ni supplementation (5 mmol/L) suppressed phenanthrene and anthracene removal (p ≤ 0.01), enhanced fluoranthene degradation relative to the control was observed. Cu, Zn, Fe and Al supplementation demonstrated significant inhibition against individual phenanthrene, anthracene and fluoranthene removal, and Cu showed a more significant effect on the degradation of these PAH compounds compared to other metals. Conversely, Mn significantly enhanced the removal of fluorene, phenanthrene and fluoranthene, but inhibited anthracene degradation. HM contamination in aquatic systems did not show any effect on naphthalene bioremediation, possible due to its rapid degradation over a short time. Thus, metals affect PAH aquatic biodegradation by consortia, depending on metal species and PAH compound, underlining the complex nature of co-contaminated systems containing HMs and PAHs. To our knowledge, this is the first study to examine the influence of HMs on PAHs' bioremediation by such PAH-degrading consortia in water.
水生环境中多环芳烃（PAHs）与重金属（HMs）的共同污染是一个全球性威胁；然而，对于这些场所中PAH的生物降解了解甚少。在本研究中，研究了由枯草芽孢杆菌和真菌顶孢霉组成的耐金属菌群在水中HMs存在的情况下对PAHs的生物降解。该菌群对测试的HMs（铁、铝、镍、铜、锰和锌）表现出比单个菌群组分更高的耐受性，并且对单个金属的耐受性随着金属浓度的增加而降低。在水生系统中不存在HMs的情况下，该菌群在10天内能够有效单独降解萘、氟、菲、蒽和荧蒽（50 mmol/L）。然而，添加镍（5 mmol/L）会抑制菲和蒽的去除（p≤0.01），但相对于对照观察到荧蒽降解增强。添加铜、锌、铁和铝对菲、蒽和荧蒽的单独去除表现出显著抑制作用，并且与其他金属相比，铜对这些PAH化合物的降解影响更显著。相反，锰显著增强了芴、菲和荧蒽的去除，但抑制了蒽的降解。水生系统中的HM污染对萘的生物修复没有任何影响，可能是由于其在短时间内快速降解。因此，金属对菌群在水中对PAH的生物降解有影响，这取决于金属种类和PAH化合物，突显了含有HMs和PAHs的共同污染系统的复杂性。据我们所知，这是第一项研究HMs对这种水中PAH降解菌群对PAHs生物修复影响的研究。
