Deltares, Subsurface and Groundwater Systems, Daltonlaan 600, 3584 BK, Utrecht, the Netherlands; Wageningen University & Research, Laboratory of Microbiology, Stippeneng 4, 6708 WE, Wageningen, the Netherlands.
Wageningen University & Research, Laboratory of Microbiology, Stippeneng 4, 6708 WE, Wageningen, the Netherlands.
Water Res. 2019 Jan 1;148:314-323. doi: 10.1016/j.watres.2018.10.050. Epub 2018 Oct 22.
EtBE is a fuel oxygenate that is synthesized from (bio)ethanol and fossil-based isobutylene, and replaces the fossil-based MtBE. Biodegradation of EtBE to harmless metabolites or end products can reduce the environmental and human health risks after accidental release. In this study, an algal-bacterial culture enriched from contaminated groundwater was used to (i) assess the potential for EtBE degradation, (ii) resolve the EtBE degradation pathway and (iii) characterize the phylogenetic composition of the bacterial community involved in EtBE degradation in contaminated groundwater. In an unamended microcosm, algal growth was observed after eight weeks when exposed to a day-night light cycle. In the fed-batch reactor, oxygen produced by the algae Scenedesmus and Chlorella was used by bacteria to degrade 50 μM EtBE replenishments with a cumulative total of 1250 μM in a day/night cycle (650 lux), over a period of 913 days. The microbial community in the fed-batch reactor degraded EtBE, using a P450 monooxygenase and 2-hydroxyisobutyryl-CoA mutase, to tert-butyl alcohol (TBA), ethanol and CO as determined using C nuclear magnetic resonance spectroscopy (NMR) and gas chromatography. Stable isotope probing (SIP) with C labeled EtBE in a fed-batch vessel showed no significant difference in community profiles of the C and C enriched DNA fractions, with representatives of the families Halomonadaceae, Shewanellaceae, Rhodocyclaceae, Oxalobacteraceae, Comamonadaceae, Sphingomonadaceae, Hyphomicrobiaceae, Candidatus Moranbacteria, Omnitrophica, Anaerolineaceae, Nocardiaceae, and Blastocatellaceae. This is the first study describing micro-oxic degradation of EtBE by an algal-bacterial culture. This algal-bacterial culture has advantages compared with conventional aerobic treatments: (i) a lower risk of EtBE evaporation and (ii) no need for external oxygen supply in the presence of light. This study provides novel leads towards future possibilities to implement algal-bacterial consortia in field-scale groundwater or wastewater treatment.
乙基叔丁基醚（EtBE）是一种由（生物）乙醇和化石基异丁烯合成的燃料含氧化合物，可替代化石基甲基叔丁基醚（MtBE）。EtBE 生物降解为无害代谢物或最终产物可以降低意外泄漏后对环境和人类健康的风险。在这项研究中，从受污染的地下水中富集的藻类-细菌培养物用于（i）评估 EtBE 降解的潜力，（ii）确定 EtBE 降解途径，以及（iii）表征参与受污染地下水中 EtBE 降解的细菌群落的系统发育组成。在未添加补充物的微宇宙中，当暴露在日夜光照周期下时，经过八周观察到藻类生长。在分批进料反应器中，藻类 Scenedesmus 和 Chlorella 产生的氧气被细菌用于降解 50μM EtBE 补料，在一天/夜周期（650 lux）中，共进行了 1250μM 的降解，持续了 913 天。分批进料反应器中的微生物群落使用 P450 单加氧酶和 2-羟基异丁酰-CoA 变位酶将 EtBE 降解为叔丁醇（TBA）、乙醇和 CO，这是通过 C 核磁共振光谱（NMR）和气相色谱确定的。在分批进料容器中用 C 标记的 EtBE 进行稳定同位素探测（SIP）显示，C 和 C 富集 DNA 分数的群落图谱没有显著差异，具有 Halomonadaceae、Shewanellaceae、Rhodocyclaceae、Oxalobacteraceae、Comamonadaceae、Sphingomonadaceae、Hyphomicrobiaceae、Candidatus Moranbacteria、Omnitrophica、Anaerolineaceae、Nocardiaceae 和 Blastocatellaceae 家族的代表。这是首次描述藻类-细菌培养物对微氧 EtBE 降解的研究。与传统的需氧处理相比，这种藻类-细菌培养物具有以下优势：（i）EtBE 蒸发的风险较低，（ii）在有光的情况下无需外部供氧。本研究为未来在现场规模的地下水或废水处理中实施藻类-细菌联合体提供了新的思路。
Zotero 插件