Abstract
Fifteen strains of Tetrachloroethylene (PCE)-degrading bacteria were isolated on agar plates from contaminated soils and a culture fluid which was acclimated to PCE with a subsoil of pond. Two strains of the isolates and others degraded PCE to trichloroethylene (TCE) and to cis-1,2-dichloroethylene (DCE) via TCE, respectively. Most of identified isolates were Bacillus species, which is the most common genus of bacteria found in soils. The acclimation of PCE-degrading bacteria with a subsoil of pond was performed readily. These results suggest that some indigenous PCE-degrading bacteria which are present in a PCE-polluted environment grow rapidly and readily acquire a higher degrading ability in the presence of favorable organic compounds as electron donors. The best PCE-degrading bacterium (Pseudomonas species) of isolates thoroughly degraded 160mg·l-1 of PCE to DCE within 4 days at 30°C.
