TY - JOUR
T1 - Anaerobic transformation and toxicity of trichlorophenols in a stable enrichment culture
AU - Madsen, Torben
AU - Aamand, Jens
PY - 1992
Y1 - 1992
N2 - The transformation and toxicity of trichlorophenols (TCPs) were studied with a methanogenic enrichment culture derived from sewage sludge. Transformation of TCPs rapidly resumed after heating of the culture at 80°C for 1 h, suggesting that the dechlorinating bacteria are spore-forming anaerobes. 2,4,6-TCP was rapidly dechlorinated via 2,4-dichlorophenol to 4- chlorophenol. During the transformation of 2,4,6-TCP, the most probable number of dechlorinating bacteria increased by 4 orders of magnitude. The most extensive dechlorination was observed in media with complex carbon sources such as yeast extract, peptone, and Casamino Acids, but glucose, galactose, and lactose were also used by the consortium. Experiments using chloramphenicol indicated that the reductive dechlorination of 2,4,6-TCP was regulated by an inducible enzyme system. The highest initial concentration at which dechlorination of 2,4,6-TCP was observed was 400 μM. 2,4,5-TCP and 3,4,5-TCP were dechlorinated to, respectively, 3,4-dichlorophenol and 3- chlorophenol at initial concentrations of ≤40 μM. Toxicity for the acid- producing and methanogenic bacteria in the consortium was a function of chemical structure, as the inhibition of these activities increased from 2,4,6-TCP, via 2,4,5-TCP, to 3,4,5-TCP.
AB - The transformation and toxicity of trichlorophenols (TCPs) were studied with a methanogenic enrichment culture derived from sewage sludge. Transformation of TCPs rapidly resumed after heating of the culture at 80°C for 1 h, suggesting that the dechlorinating bacteria are spore-forming anaerobes. 2,4,6-TCP was rapidly dechlorinated via 2,4-dichlorophenol to 4- chlorophenol. During the transformation of 2,4,6-TCP, the most probable number of dechlorinating bacteria increased by 4 orders of magnitude. The most extensive dechlorination was observed in media with complex carbon sources such as yeast extract, peptone, and Casamino Acids, but glucose, galactose, and lactose were also used by the consortium. Experiments using chloramphenicol indicated that the reductive dechlorination of 2,4,6-TCP was regulated by an inducible enzyme system. The highest initial concentration at which dechlorination of 2,4,6-TCP was observed was 400 μM. 2,4,5-TCP and 3,4,5-TCP were dechlorinated to, respectively, 3,4-dichlorophenol and 3- chlorophenol at initial concentrations of ≤40 μM. Toxicity for the acid- producing and methanogenic bacteria in the consortium was a function of chemical structure, as the inhibition of these activities increased from 2,4,6-TCP, via 2,4,5-TCP, to 3,4,5-TCP.
KW - chlorinated phenols
KW - anaerobic
KW - reductive dechlorination
UR - http://www.scopus.com/inward/record.url?scp=0026532735&partnerID=8YFLogxK
U2 - 10.1128/aem.58.2.557-561.1992
DO - 10.1128/aem.58.2.557-561.1992
M3 - Article
C2 - 1610181
AN - SCOPUS:0026532735
SN - 0099-2240
VL - 58
SP - 557
EP - 561
JO - Applied and Environmental Microbiology
JF - Applied and Environmental Microbiology
IS - 2
ER -