Akademik Veri Yönetim Sistemi
INTERNATIONAL BIODETERIORATION & BIODEGRADATION, cilt.51, sa.2, ss.119-127, 2003 (SCI-Expanded)
The purpose of this research was to determine the level of toxicity of (tetrachloroethylene) (TCE) and carbontetrachloride (CT) in batch cultures inoculated with three sources of inoculum, namely granular sludge, anaerobic sludge and Methanosaeta sp., when glucose was the carbon source. Also, to evaluate the biodegradation of TCE and CT when cultures set in the same conditions as above were acclimated for 60 days in the presence of various levels of TCE and CT. Although the concentrations of TCE and CT resulting in 50% inhibition of the rate of methane gas production (IC50) values was found to be 18 mg/l TCE and 1.9 mg/l CT, respectively; 75 and 83% removal efficiencies were obtained in 8 mg/l CT and 30 mg/l TCE in cultures inoculated with granular sludge at the end of acclimation studies (60 days). The methane gas and specific methanogenic activity (SMA) were 50% of control in samples containing 15 mg/l CT at the end of the 60 day acclimation period. The cumulative methane gas and SMA were also found to be approximately 50% of control at a TCE concentration of 40 mg/l at the end of 60 days of adaptation. The IC50 values for TCE were found to be 15 and 10 mg/l in cultures containing Methanosaeta (Methanothrix) sp. and anaerobic sludge, respectively. The IC50 values for CT were calculated as 1.8 and 1.7 mg/l in cultures containing Methanosaeta (Methanothrix) sp. and anaerobic sludge, respectively. Among all the sources of inoculum granular sludge exhibited the best results. Low SMA, and inhibitions in methane gas production were achieved in cultures containing Methanosaeta (Methanothrix) sp. and anaerobic sludge compared to granulated sludge cultures. 76, 33% TCE and 62, 58% CT removal efficiencies were determined in cultures inoculated with Methanosaeta (Methanothrix) sp. and anaerobic sludge, respectively. (C) 2002 Elsevier Science Ltd. All rights reserved.