Efficiency of surfactant-enhanced bioremediation of aged polycyclic aromatic hydrocarbon-contaminated soil: Link with bioavailability and the dynamics of the bacterial community
Efficiency of surfactant-enhanced bioremediation of aged polycyclic aromatic hydrocarbon-contaminated soil: Link with bioavailability and the dynamics of the bacterial community
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DOI：
10.1016/j.scitotenv.2018.03.303
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发表时间：
2018-09-01
影响因子：
9.8
通讯作者：
Morelli, Irma S.
中科院分区：
文献类型：
--
作者：
Cecotti, Martina;Coppotelli, Bibiana M.;Morelli, Irma S.
在TritonX-100处理的微宇宙中，在临界胶束浓度（T-CMC）和在两个亚CMC剂量的细菌群落动态，生物有效性和生物降解的多环芳烃（PAHs）的长期污染土壤的变化进行了分析。只有低于CMC剂量的微生态系统达到的吸附多环芳烃浓度显著低于对照组：166 +/- 32和135 +/- 4毫克/千克（-1）干土壤对266 +/- 51毫克/千克（-1）;因此，观察到高分子量和低分子量多环芳烃生物降解的增加。经过63天的孵育焦磷酸测序数据证明差异的多样性和组合物之间的表面活性剂改性的微观世界和控制，与那些与次CMC剂量含有优势的订单鞘氨醇单胞菌，酸杆菌，芽单胞菌（组已知的多环芳烃降解能力）。T-CMC微宇宙表现出较低的丰富度和多样性指数与显着的优势，黄单胞菌目，主要代表的寡养单胞菌属，多环芳烃和Triton X-100降解细菌。在T-CMC微观世界中，初始表面张力为35 mN m（-1），在孵育63天后，记录到增加至40 mN m（-1）。先前的观察和气相色谱数据表明，表面活性剂可能已被降解的CMC由一个高度选择性的细菌群落，从而对多环芳烃生物降解产生负面影响。这项工作获得了强有力的证据，参与物理化学和生物学的影响，确定所研究的微观世界的不同行为。这里报道的结果有助于显着的优化，表面活性剂增强的生物修复策略，长期污染的土壤，因为低于CMC的剂量的应用将降低整体成本。(C)2018 Elsevier B. V.版权所有。
Shifts in the bacterial-community dynamics, bioavailability, and biodegradation of polycyclic aromatic hydrocarbons (PAHs) of chronically contaminated soil were analyzed in Triton X-100-treated microcosms at the critical micelle concentration (T-CMC) and at two sub-CMC doses. Only the sub-CMC-dose microcosms reached sorbed-PAH concentrations significantly lower than the control: 166 +/- 32 and 135 +/- 4 mg kg(-1) dry soil versus 266 +/- 51 mg kg(-1); consequently an increase in high- and low-molecular-weight PAHs biodegradation was observed. After 63 days of incubation pyrosequencing data evidenced differences in diversity and composition between the surfactant-modified microcosms and the control, with those with sub-CMC doses containing a predominance of the orders Sphingomonadales, Acidobacteriales, and Gemmatimonadales (groups of known PAHs-degrading capability). The T-CMC microcosm exhibited a lower richness and diversity index with a marked predominance of the order Xanthomonadales, mainly represented by the Stenotrophomonas genus, a PAHs- and Triton X-100-degrading bacterium. In the T-CMC microcosm, whereas the initial surface tension was 35 mN m(-1), after 63 days of incubation an increase up to 40 mN m(-1) was registered. The previous observation and the gas-chromatography data indicated that the surfactant may have been degraded at the CMC by a highly selective bacterial community with a consequent negative impact on PAHs biodegradation. This work obtained strong evidence for the involvement of physicochemical and biologic influences determining the different behaviors of the studied microcosms. The results reported here contribute significantly to an optimization of, surfactant-enhanced bioremediation strategies for chronically contaminated soil since the application of doses below the CMC would reduce the overall costs. (C) 2018 Elsevier B.V. All rights reserved.