title: Aerobic biodegradation of tert-butyl alcohol (TBA) by psychro- and thermo-tolerant cultures derived from granular activated carbon (GAC).
abstract: Tert-butyl alcohol (TBA) is a metabolite of methyl tert-butyl ether and is itself possibly a fuel oxygenate. The goals of this study were to enrich and characterize TBA-degrading micro-organism(s) from a granular activated carbon (GAC) unit currently treating TBA. The results reported herein describe the first aerobic, TBA-degrading cultures derived from GAC. Strains KR1 and YZ1 were enriched from a GAC sample in a bicarbonate-buffered freshwater medium. TBA was degraded to 10% of the initial concentration (2-5 mM) within 5 days after initial inoculation and was continuously degraded within 1 day of each re-amendment. Resting cell suspensions mineralized 70 and 60% of the TBA within 24 h for KR1 and YZ1, respectively. Performance optimization with resting cells was conducted to investigate kinetics and the extent of TBA degradation as influenced by oxygen, pH and temperature. The most favorable temperature was 37 degrees C; however, TBA was degraded from 4 to 60 degrees C, indicating that the culture will sufficiently treat groundwater without heating. This is also the first report of psychrotolerant or thermotolerant TBA biodegradation. The pH range for TBA degradation ran from 5.0 to 9.0. Phylogenetic data using a partial 16S rRNA gene sequence (570 bases) suggest that the primary members of KR1 and YZ1 include uncharacterized organisms within the genera Hydrogenophaga, Caulobacter, and Pannonibacter.
authors.affiliation: Department of Civil and Environmental Engineering, University of Illinois-Urbana Champaign, NCEL 205 N. Mathews, Urbana, IL 61801, USA.
authors.forename: Kimberly M
authors.initials: KM
authors.lastname: Reinauer
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhang
authors.forename: Xiaomin
authors.initials: X
authors.lastname: Yang
authors.forename: Kevin T
authors.initials: KT
authors.lastname: Finneran
mesh_terms: D001420:Bacteria, Aerobic / Q000378:metabolism*; D001673:Biodegradation, Environmental; D002244:Carbon / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D010802:Phylogeny; D013696:Temperature; D020002:tert-Butyl Alcohol / Q000378:metabolism*
chemical_list: D002244:Carbon; D020002:tert-Butyl Alcohol