Chlorophenol degradation coupled to sulfate reduction

Journal Article · Thu Nov 01 00:00:00 EST 1990 · Applied and Environmental Microbiology; (USA)

OSTI ID:5950279

Haeggblom, M M; Young, L Y ^[1]

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1. New York University Medical Center, NY (USA)

We studied chlorophenol degradation under sulfate-reducing conditions with an estuarine sediment inoculum. These cultures degraded 0.1 mM 2-, 3-, and 4-chlorophenol and 2,4-dichlorophenol within 120 to 220 days, but after refeeding with chlorophenols degradation took place in 40 days or less. Further refeeding greatly enhanced the rate of degradation. Sulfate consumption by the cultures corresponded to the stoichiometric values expected for complete oxidation of the chlorophenol to CO{sub 2}. Formation of sulfide from sulfate was confirmed with a radiotracer technique. No methane was formed, verifying that sulfate reduction was the electron sink. Addition of molybdate, a specific inhibitor of sulfate reduction, inhibited chlorophenol degradation completely. These results indicate that the chlorophenols were mineralized under sulfidogenic conditions and that substrate oxidation was coupled to sulfate reduction. In acclimated cultures the three monochlorophenol isomers and 2,4-dichlorophenol were degraded at rates of 8 to 37 {mu}mol liter{sup {minus}1} day{sup {minus}1}. The relative rates of degradation were 4-chlorophenol > 3-chlorophenol > 2-chlorophenol, 2,4-dichlorophenol. Sulfidogenic cultures initiated with biomass from an anaerobic bioreactor used in treatment of pulp-bleaching effluents dechlorinated 2,4-dichlorophenol to 4-chlorophenol, which persisted, whereas 2,6-dichlorophenol was sequentially dechlorinated first to 2-chlorophenol and then to phenol.

• OSTI ID: 5950279
• Journal Information: Applied and Environmental Microbiology; (USA), Vol. 56:11; ISSN 0099-2240
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
CHLORINATED AROMATIC HYDROCARBONS
BIODEGRADATION
SULFATES
REDUCTION
ESTUARIES
PHENOLS
SEDIMENTS
AROMATICS
CHEMICAL REACTIONS
DECOMPOSITION
HALOGENATED AROMATIC HYDROCARBONS
HYDROXY COMPOUNDS
ORGANIC CHLORINE COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
OXYGEN COMPOUNDS
SULFUR COMPOUNDS
SURFACE WATERS
540310* - Environment
Aquatic- Basic Studies- (1990-)