Maciel Helena, Mathis Hugues, Lopes Ferreira Nicolas, Lyew Darwin, Guiot Serge, Monot Frédéric, Greer Charles W, Fayolle-Guichard Françoise
Institut Francais du Petrole, Rueil-Malmaison, France.
J Mol Microbiol Biotechnol. 2008;15(2-3):190-8. doi: 10.1159/000121330. Epub 2008 Jul 28.
Mycobacterium austroafricanum IFP 2012 is able to slowly grow on methyl tert-butyl ether (MTBE), a fuel oxygenate widely used as a gasoline additive. The potential of M. austroafricanum IFP 2012 for aerobic MTBE degradation was investigated in the presence of a secondary carbon source, isopropanol. The strain was then tested for MTBE biodegradation at the laboratory-scale in a fixed-bed reactor using perlite as the matrix, and isopropanol was injected once a week to maintain M. austroafricanum IFP 2012 biomass inside the perlite bed. The biofilter was operated for 85 days at an influent flow rate of 20 ml/h by varying the MTBE concentration from 10 to 20 mg/l. The hydraulic retention time was fixed at 5 days. The removal of MTBE depended on the inlet MTBE concentration and a MTBE removal efficiency higher than 99% was obtained for MTBE concentrations up to 15 mg/l. A set of 16S rRNA gene primers specific for M. austroafricanum species was used to analyze the DNA extracted from the biofilter effluent in order to detect the presence of M. austroafricanum IFP 2012 and to estimate the effect of periodic injections of isopropanol on the release of the strain from the perlite bed. The results demonstrated that the injection of isopropanol served to maintain an active MTBE degrading biomass in the biofilter and that this system could be used to effectively treat MTBE contaminated groundwater.
非洲南部分枝杆菌IFP 2012能够在甲基叔丁基醚（MTBE）上缓慢生长，MTBE是一种广泛用作汽油添加剂的燃料含氧化合物。在存在二级碳源异丙醇的情况下，研究了非洲南部分枝杆菌IFP 2012对MTBE进行好氧降解的潜力。然后在实验室规模的固定床反应器中，以珍珠岩为基质，对该菌株进行MTBE生物降解测试，并每周注入一次异丙醇以维持珍珠岩床内非洲南部分枝杆菌IFP 2012的生物量。通过将MTBE浓度从10 mg/l变化到20 mg/l，生物滤池以20 ml/h的进水流量运行85天。水力停留时间固定为5天。MTBE的去除取决于进水MTBE浓度，对于高达15 mg/l的MTBE浓度，MTBE去除效率高于99%。使用一组对非洲南部分枝杆菌物种特异的16S rRNA基因引物，分析从生物滤池流出物中提取的DNA，以检测非洲南部分枝杆菌IFP 2012的存在，并评估定期注入异丙醇对该菌株从珍珠岩床释放的影响。结果表明，注入异丙醇有助于在生物滤池中维持活跃的MTBE降解生物量，并且该系统可用于有效处理受MTBE污染的地下水。
