Isolation and Characterization of Chlorobenzene Degrading Bacteria

Abstract:

In this study, we isolated and characterized chlorobenzene degrading bacteria from the effluent and sludge samples of one chemical plant. Minimal medium supplemented with chlorobenzene as sole carbon source was used during the enrichment and domestication process. Seven major bacterial isolates were obtained and purified. Their 16S rRNA genes were amplified by PCR for sequencing and their identities were determined with homology comparisons. Five of the seven isolates belong to Actinomycetales including Kocuria KD139, Rhodococcus KD140, Rhodococcus KD142, Arthrobacter KD230, and Arthrobacter KD232; one is classified as Bacillus d KD178; and another one as Stenotrophomonas KD237. The phylogenetic tree was also constructed based on the analysis of 16S rRNA gene sequences. Chloro- benzene concentrations were quantified with gas chromatography to investigate the bio-degradation rates of the isolated strains. Stenotrophomonas KD237 degraded 60.78% chlorobenzene in the minimal medium within 24 h.