Desulfurization of Dibenzothiophene by Pseudomonas aeruginosa Isolated from Iraqi Soils

A dibenzothiophene (DBT) utilizing bacteria, as the sole source of sulfur, were isolated from soil samples contaminated with hydrocarbons. In this study, an effective enrichment technique was applied to isolate bacterial isolates with capabilities to utilize dibenzothiophene (DBT) as a model compound of polyaromatic sulfur heterocyclic compounds (PASHs). From forty samples, sixty three bacterial isolates were obtained and three of them were characterized as biodesulfurising Pseudomonas aeruginosa. A convenient spectrophotometric assay (Gibbs’ assay) was used to determine the quantity of desulfurized product (Hydroxybiphenyl HBP) by these isolates, also these isolates were capable to utilize ethanol as C- source.