Effect of MTBE on growth and metabolism of degrading microorganisms

摘要

Methyl tert-butyl ether (MTBE) is a synthetic compound that was developed as a technological solution to a technology-derived problem created by air pollution from vehicle emissions. Because of its undesirable effects on drinking water and ecologically harmful effects, MTBE removal has become a public health and environmental concern. Potential method used for MTBE removal from soils and aquifers is microbial decomposition. Genotoxicity of MTBE was monitored by Ames test with Salmonella typhimurium his~-(TA98, TA 100, YG1041, YG1042) as indicator strains. Concentrations of MTBE/plate tested were 3.0 mg and1.5mg. Obtained results did not prove the MTBE genotoxicity. Among the MTBE aerobic degradation products of indigenous bacterial strains tert-butyl alcohol (TBA) was found using GC. The genotoxicity of TBA was tested using the identical system. All so far measured data indicate that MTBE will be cometabolically oxidized by monooxygenase (MO) enzyme activity that is induced by oxidation of n-alkanes under aerobic conditions. The MO enzyme requires molecular oxygen to oxidize the target chemical; this process is called β-oxidation and is common mechanism for n-alkane biodegradation. Its role in MTBE biodegradation is evaluated.