Biodegradation of carbazole by newly isolated Acinetobacter spp.

In this study, two bacterial isolates designated Alp6 and Alp7 were isolated from soil collected from dye industries and screened for their ability to degrade carbazole. Growing cells of the isolates Alp6 and Alp7 could degrade 99.9% and 98.5% of carbazole, respectively in 216 h. The specific activity for degradation by the resting cells of Alp6 was found to be 7.96 μmol/min/g dry cell weight, while for Alp7 it was 5.82 μmol/min/g dry cell weight. Phylogenetic analysis based on 16S rDNA gene sequences showed that isolates Alp6 and Alp7 belonged to the genus Acinetobacter. To the best of our knowledge, this is the first report on the Acinetobacter spp. showing utilization of carbazole as carbon and nitrogen source.