Degradation of pentachlorophenol by anaerobic subsurface microorganisms

Microbial populations from subsurface soil collected from a hydrocarbon contaminated site and a pristine site with no history of contamination had the ability to degrade pentachlorophenol (PCP) in anaerobic enrichment cultures. Increasing concentrations of PCP in nitrate, sulfate and yeast extract-mineral salts media were used to acclimate the cultures. Nitrate enrichments, previously incubated in an anaerobic phenol-mineral salts medium, showed 23% degradation in medium containing 40 μg ml⁻¹ PCP during a 32 d incubation period. Cultures not adapted to phenol degradation did not degrade PCP at concentrations over 20 μg ml⁻¹. Enrichment cultures grown in the anaerobic yeast extract-mineral salts medium did not degrade PCP at concentrations over 20 μg ml⁻¹ and phenol adaptation did not enhance PCP degradation. The sulfate reducing enrichment containing 1 μg ml⁻¹ PCP showed 71.3% degradation after 32 d incubation. No degradation occurred at or above 5 μg ml⁻¹ PCP. PCP intermediates, 2,4,6-trichlorophenol (TCP) and 3,4,5 TCP were found in the spent culture of the nitrate reducing enrichment. In the spent culture of the sulfate reducing enrichment, 3,4,5 TCP and 2,3,4,5-tetrachlorophenol were found. Attempts to obtain a pure culture of an anaerobic PCP degrading bacterium were unsuccessful.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Microbiology

Department dc:contributor.department

Microbiology

Grantor dc:publisher

Virginia Polytechnic Institute and State University

Year dc:date.issued

1989

Author dc:creator

• Baranow, Steven A.

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language.iso

en_US

Handle dc:identifier.uri

http://hdl.handle.net/10919/54376

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/54376