Effect of trichloroethylene loading on mixed methanotrophic community stability

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:474274

Strand, S E; Walter, G A; Stensel, H D ^[1]

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1. Univ. of Washington, Seattle, WA (United States)

There is concern that trichloroethylene (TCE) degradation by methanotrophic cultures cannot be maintained due to metabolite toxicity. The purpose of this research was to understand the effects of metabolite toxicity on methanotrophic cultures and to define operating conditions that might minimize these effects. A mixed methanotrophic culture was maintained with continuous supply of methane a/nd nutrients as TCE loading was increased from 4 to 10 {micro}g TCE/(mg protein-d). The maximum sustainable ratio of TCE degraded to methane consumed was 6 {micro}g TCE/mg methane. Biomass, methane consumption, and TCE degradation fell precipitously when the loading exceeded 10 {micro}g TCE/(mg-protein-d). Reactor failure was preceded by a fall in the soluble methane monooxygenase (sMMO) activities. Phospholipid fatty acid analyses of the biomass before and after failure indicated a shift from a type II to a type I methanotrophic culture, a change that suggests a decreased ability to cometabolize TCE. These results suggest that continued exposure of a mixed methanotrophic culture to levels of TCE that damage cell viability can result in loss of cometabolic capabilities and a change in the population of the methanotrophic culture.

• OSTI ID: 474274
• Report Number(s): CONF-950483--; ISBN 1-57477-005-5
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
56 BIOLOGY AND MEDICINE
APPLIED STUDIES
BIODEGRADATION
CHLORINATED ALIPHATIC HYDROCARBONS
IN-SITU PROCESSING
METHANE
METHANOTROPHIC BACTERIA
REMEDIAL ACTION
TOXICITY