Biotransformation of trichloroethene by pure bacterial cultures

Abstract

From natural samplex eleven isolates were obtained which were capable of cometabolic degradation of trichlsoroethylene (TCE) by an enzyme system for phenol degradation. At an initial TCE concentration of 1 mg/l, the resting cells of particular cultures degraded 33 - 94 % TCE in 24 hours and their transformation capacities ranged from 0.3 to 3.1 mg TCE/g organic fraction. Further an analysis of a mixed phenol-fed culture with an excellent TCE-degrading ability was performed. A markedly minority isolate represented in the consortium was found to be responsible for this property. This culture, designated RF2, degraded TCE even at a low inoculum density and attained a transformation capacity of 14.7 mg TCE/g. The increase in chslorides concentration after degradation was quantitative when compared with the decrease in organically bound chlorine. Attention was further given to the effect of dimethyldisulphide on the degree of TCE degradation while proving this substance can significantly reduce dthe degrading ability of some tested cultures (as much as 60 %)

however, it does not cause this inhibition with others.