Premium
Anaerobic mineralization of pentachlorophenol (PCP) by combining PCP‐dechlorinating and phenol‐degrading cultures
Author(s) -
Yang Suyin,
Shibata Atsushi,
Yoshida Naoko,
Katayama Arata
Publication year - 2008
Publication title -
biotechnology and bioengineering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.136
H-Index - 189
eISSN - 1097-0290
pISSN - 0006-3592
DOI - 10.1002/bit.22032
Subject(s) - pentachlorophenol , phenol , mineralization (soil science) , chemistry , biodegradation , bioremediation , reductive dechlorination , anoxic waters , microbial consortium , environmental chemistry , sulfate , bioaugmentation , microorganism , electron acceptor , microbial biodegradation , anaerobic exercise , sulfate reducing bacteria , organic chemistry , bacteria , biology , nitrogen , physiology , genetics
The dechlorination and mineralization of pentachlorophenol (PCP) was investigated by simultaneously or sequentially combining two different anaerobic microbial populations, a PCP‐dechlorinating culture capable of the reductive dechlorination of PCP to phenol and phenol‐ degrading cultures able to mineralize phenol under sulfate‐ or iron‐reducing conditions. In the simultaneously combined mixture, PCP (about 35 µM) was mostly dechlorinated to phenol after incubation for 17 days under sulfate‐reducing conditions or for 22 days under iron‐reducing conditions. Thereafter, the complete removal of phenol occurred within 40 days under both conditions. In the sequentially combined mixture, most of the phenol, the end product of PCP dechlorination, was degraded within 12 days of inoculation with the phenol degrader, without a lag phase, under both sulfate‐ and iron‐reducing conditions. In a radioactivity experiment, [ 14 C–U]–PCP was mineralized to 14 CO 2 and 14 CH 4 by the combined anaerobic microbial activities. Analysis of electron donor and acceptor utilization and of the production and consumption of H 2 , CO 2 , and CH 4 suggested that the dechlorinating and degrading microorganisms compete with other microorganisms to perform PCP dechlorination and part of the phenol degradation in complex anoxic environments in the presence of electron donors and acceptors. The presence of a small amount of autoclaved soil slurry in the medium was possibly another advantageous factor in the successful dechlorination and mineralization of PCP by the combined mixtures. This anaerobic–anaerobic combination technology holds great promise as a cost‐effective strategy for complete PCP bioremediation in situ. Biotechnol. Bioeng. 2009;102: 81–90. © 2008 Wiley Periodicals, Inc.