São Paulo State University (UNESP), Institute of Biosciences, Department of General and Applied Biology, Laboratory of Environmental and Industrial Mycology, Rio Claro, SP, 01049-010, Brazil.
State University of Campinas (UNICAMP), Research Center for Chemistry, Biology, and Agriculture, Microbial Resources Division, Campinas, SP, 13083-970, Brazil.
J Microbiol. 2021 Jul;59(7):634-643. doi: 10.1007/s12275-021-0395-2. Epub 2021 May 15.
Soil contamination with diesel oil is quite common during processes of transport and storage. Bioremediation is considered a safe, economical, and environmentally friendly approach for contaminated soil treatment. In this context, studies using hydrocarbon bioremediation have focused on total petroleum hydrocarbon (TPH) analysis to assess process effectiveness, while ecotoxicity has been neglected. Thus, this study aimed to select a microbial consortium capable of detoxifying diesel oil and apply this consortium to the bioremediation of soil contaminated with this environmental pollutant through different bioremediation approaches. Gas chromatography (GC-FID) was used to analyze diesel oil degradation, while ecotoxicological bioassays with the bioindicators Artemia sp., Aliivibrio fischeri (Microtox), and Cucumis sativus were used to assess detoxification. After 90 days of bioremediation, we found that the biostimulation and biostimulation/bioaugmentation approaches showed higher rates of diesel oil degradation in relation to natural attenuation (41.9 and 26.7%, respectively). Phytotoxicity increased in the biostimulation and biostimulation/bioaugmentation treatments during the degradation process, whereas in the Microtox test, the toxicity was the same in these treatments as that in the natural attenuation treatment. In both the phytotoxicity and Microtox tests, bioaugmentation treatment showed lower toxicity. However, compared with natural attenuation, this approach did not show satisfactory hydrocarbon degradation. Based on the microcosm experiments results, we conclude that a broader analysis of the success of bioremediation requires the performance of toxicity bioassays.
土壤受到柴油污染在运输和储存过程中是很常见的。生物修复被认为是一种安全、经济且环保的受污染土壤处理方法。在这种情况下，使用烃类生物修复的研究侧重于总石油烃 (TPH) 分析，以评估处理效果，而忽略了生态毒性。因此，本研究旨在选择能够降解柴油的微生物群落，并将该群落应用于通过不同生物修复方法对受这种环境污染物污染的土壤进行生物修复。气相色谱 (GC-FID) 用于分析柴油降解，而使用生物指示剂盐水丰年虾 (Artemia sp.)、发光菌 (Aliivibrio fischeri)（Microtox）和黄瓜 (Cucumis sativus) 的生态毒理学生物测定来评估解毒作用。在生物修复 90 天后，我们发现生物刺激和生物刺激/生物增强方法与自然衰减相比，显示出更高的柴油降解率（分别为 41.9%和 26.7%）。在降解过程中，生物刺激和生物刺激/生物增强处理中的植物毒性增加，而在 Microtox 测试中，这些处理中的毒性与自然衰减处理中的毒性相同。在植物毒性和 Microtox 测试中，生物增强处理显示出较低的毒性。然而，与自然衰减相比，这种方法并未显示出令人满意的烃类降解。基于微宇宙实验结果，我们得出结论，更广泛地分析生物修复的成功需要进行毒性生物测定。
