Desulfurization of Dibenzothiophene by a Novel Strain Brevibacillus Invocatus C19 Isolated from Egyptian Coke

Abstract

In this study, an effective enrichment technique was applied to isolate different bacterial strains with capabilities to utilize dibenzothiophene (DBT) as a model compound of polyaromatic sulfur heterocyclic compounds (PASHs). Twenty-eight different desulfurizing bacterial strains were isolated from a mineral coke sample with sulfur content of 3.8%. Only nine of them showed the ability to utilize DBT as a sole-sulfur source through the 4S-pathway without altering its hydrocarbon skeleton. From all; a Gram +ve bacterial isolate designated C19 showed a higher biodesulfurization (BDS) efficiency relevant to the well-known biodesulfurizing bacterium strain R. erythropolis IGTS8, recording 66.85% and 50% removal of 1000 ppm DBT with the production of 31.98 and 31.34 ppm 2-hydroxybiphenyl (2-HBP), as a dead end product, respectively. C19 was identified by 16S rDNA gene sequence analysis to be Brevibacillus invocatus C19 (NCBI Gene Bank Accession no. KC999852) with similarity of 99.05%. BDS of different PASHs was also studied and Brevibacillus invocatus C19 showed good BDS capabilities compared to those of IGTS8.