POLYCYCLIC AROMATIC HYDROCARBON BIODEGRADATION OF BACTERIAL STRAINS ISOLATED FROM HERBICIDE/DIOXIN DETOXIFICATION BIOREACTOR

Abstract

From  detoxification  tteatment  of  herbicide/dioxin  contaminated  soil  in  semianaerobic  bioreactor,  four chrysene degraders  and two pyrene degraders were  isolated. Among these bacterial  strains, only two  sfrains, BDNRl  and  BDNR4, were  able to utilize  soil  exfraction  containing  2,3,7,8-TCDD  and  2,4-D,  respectively. Both bacterial  sttains belong to Gram negative. BDNRl  and BDNR4 degraded  seven different  PAHs  such as phenanthrene,  anthracene,  fluoranthene,  naphthalene,  fluorene,  pyrene  and  chrysene.  After   7  days  of

incubation,  BDNRl  degraded  86.2% pyrene,  50% anthracene,  50% naphthalene,  50% phenanthrene, 44.4% fluoranthrene  and 20% fluorene; BDNR4 bacterial  strain also degraded  61.5 % pyrene, 50% anthracene, 50%

naphthalene,  65.3% fluoranthrene, 47%  fluorene  and  23.1% naphthalene.  Based  on  several  morphological properties  and partial  sequence of  16S rRNA  gene, BDNRl  sfrain  should belong  to the genus Pseudomonas

and named  as Pseudomonas sp. BDNRl.  The partial  sequence of  16S rRNA  gene ofthe  sfrain  BDNRl  was deposited in Genbank with an assession number EU726633.