title: Biodegradation of Methyl Tertiary Butyl Ether (MTBE) by a Microbial Consortium in a Continuous Up-Flow Packed-Bed Biofilm Reactor: Kinetic Study, Metabolite Identification and Toxicity Bioassays.
abstract: This study investigated the aerobic biodegradation of methyl tertiary-butyl ether (MTBE) by a microbial consortium in a continuous up-flow packed-bed biofilm reactor using tezontle stone particles as a supporting material for the biofilm. Although MTBE is toxic for microbial communities, the microbial consortium used here was able to resist MTBE loading rates up to 128.3 mg L-1 h-1, with removal efficiencies of MTBE and chemical oxygen demand (COD) higher than 90%. A linear relationship was observed between the MTBE loading rate and the MTBE removal rate, as well as between the COD loading rate and the COD removal rate, within the interval of MTBE loading rates from 11.98 to 183.71 mg L-1 h-1. The metabolic intermediate tertiary butyl alcohol (TBA) was not detected in the effluent during all reactor runs, and the intermediate 2-hydroxy butyric acid (2-HIBA) was only detected at MTBE loading rates higher than 128.3 mg L-1 h-1. The results of toxicity bioassays with organisms from two different trophic levels revealed that the toxicity of the influent was significantly reduced after treatment in the packed-bed reactor. The packed-bed reactor system used in this study was highly effective for the continuous biodegradation of MTBE and is therefore a promising alternative for detoxifying MTBE-laden wastewater and groundwater.
authors.affiliation: Departamento de Ingeniería Bioquímica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, México.
authors.forename: Guadalupe
authors.initials: G
authors.lastname: Alfonso-Gordillo
authors.affiliation: Unidad de Biotecnología y Prototipos, Facultad de Estudios Superiores-Iztacala, Universidad Nacional Autónoma de México, Tlalnepantla, Estado de México, México.|Laboratorio Nacional en Salud, Facultad de Estudios Superiores-Iztacala, Universidad Nacional Autónoma de México, Tlalnepantla, Estado de México, México.
authors.forename: César Mateo
authors.initials: CM
authors.lastname: Flores-Ortiz
authors.affiliation: Departamento de Ingeniería Bioquímica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, México.
authors.forename: Liliana
authors.initials: L
authors.lastname: Morales-Barrera
authors.affiliation: Departamento de Ingeniería Bioquímica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, México.
authors.forename: Eliseo
authors.identifier: http://orcid.org/0000-0002-8470-0711
authors.initials: E
authors.lastname: Cristiani-Urbina
mesh_terms: D001673:Biodegradation, Environmental; D018441:Biofilms; D001681:Biological Assay; D018533:Biomass; D019149:Bioreactors; D008738:Methyl Ethers / Q000737:chemistry / Q000378:metabolism*; D059013:Microbial Consortia
chemical_list: D008738:Methyl Ethers; C043243:methyl tert-butyl ether