Cometabolism of methyl tert-butyl ether (MTBE) with alkanes |
| |
Authors: | Verónica Nava Marcia Morales Sergio Revah |
| |
Institution: | (1) Instituto Mexicano del Petróleo, Programa de Medio Ambiente y Seguridad, Eje Central Lázaro Cárdenas No. 152 Col. San Bartolo Atepehuacan, C.P. 07730 México D.F., México;(2) Universidad Autónoma Metropolitana-Cuajimalpa. C/O UAM- Iztapalapa, Av. San Rafael Atlixco No. 186, C.P. 09340 México D.F., México |
| |
Abstract: | The release of methyl tert-butyl ether (MTBE) to the environment, mainly from damaged gasoline underground storage tanks or
distribution systems spills, has provoked extended groundwater pollution. Biological treatments are, in general, a good alternative
for bioremediation of polluted sites; however, MTBE elimination from environment has constituted a challenge because of its
chemical structure and physicochemical properties. The combination of a stable ether link and the branched moiety hinder biodegradation.
Initial studies found MTBE to be highly recalcitrant but, in the last decade, reports of its biodegradation have been published
first under aerobic conditions and just recently under anaerobic conditions. Microbial MTBE degradation is characterized by
bacteria having low growth rates (0.35 day−1) and biomass yields (average value 0.24 g biomass/g MTBE). Alternatively, cometabolism (defined as the transformation of
a non-growth substrate in the obligate presence of a growth substrate), has been considered since it uncouples biodegradation
of the contaminant from growth, reducing the long adaptation and propagation period. This period has been reported to be of
several months in systems where it is degraded as sole carbon source. Cometabolic degradation rates are between 0.3 and 61 nmol/min/mg
protein (in the same range of direct aerobic metabolism). However, a major concern in MTBE cometabolism is that the accumulation
of tert-butyl alcohol (TBA) may, under certain cases, result in an incomplete site cleanup. This paper reviews in detail the
implicated enzymes and field treatments for the cometabolism of MTBE degradation with alkanes as growth substrates. |
| |
Keywords: | Alkanes Biodegradation Cometabolism Co-oxidation Monooxygenases |
本文献已被 SpringerLink 等数据库收录! |
|