Chiu, Tzu-ChuanTzu-ChuanChiuJUI-HUNG YENHsieh, Yar-NingYar-NingHsiehWang, Yei-ShungYei-ShungWang2018-09-102018-09-102005-09http://www.scopus.com/inward/record.url?eid=2-s2.0-21844446844&partnerID=MN8TOARShttp://scholars.lib.ntu.edu.tw/handle/123456789/315405A pathway of dieldrin transformation to aldrin by epoxide reduction was found in this study. Investigation of dieldrin degradation under anaerobic conditions was performed with a mixed culture containing indigenous microorganisms obtained from sediment of the Er-Jen River in Taiwan. During the incubation, the transformation of dieldrin to aldrin was analyzed by GC-ECD and GC-MS. Effects of incubation factors including dieldrin concentrations, incubation temperatures and kinds of carbon sources on the degradation of dieldrin were also studied. Original concentrations (from 0.5 to 10 μg ml-1) of dieldrin affect the transformation rate of dieldrin, and lower concentrations indicated the higher degradation rates. But once the concentration higher than 100 μg ml-1, almost no degradation occurred. The optimal temperature for degradation in mixed culture was found at 40°C in this study. Dieldrin transformation rates varied with the type of major carbon sources in the mixed culture and were in order of yeast extract > sodium acetate > glucose. In addition, the denaturing gradient gel electrophoresis (DGGE) fingerprint revealed that four microbials evolved in dieldrin-amended cultures, but not in the dieldrin-free cultures. Partial sequence of 16S rDNA for these four organisms exhibited 94-99% similarity to those of genera Clostridium, Acidaminobacter and an uncultured bacterial group. These results suggest that the four microbials might promote the dieldrin transformation.Anaerobic transformationBiodegradationDenaturing gradient gel electrophoresis (DGGE)DieldrinEpoxide reduction[SDGs]SDG14journal article10.1016/j.chemosphere.2005.02.0182-s2.0-21844446844WOS:000231774100002