Biodesulfurization of dibenzothiophene, its alkylated derivatives and crude oil by a newly isolated strain Pantoea agglomerans D23W3

Biocatalytic desulfurization (BDS) of fuels has been shown to be a potential alternative to the conventional hydrodesulfurization (HDS) process used in refineries, since HDS cannot remove the heterocyclic organo-sulfur compounds such as dibenzothiophene (DBT). Herein the isolation of a DBT desulfurizing mesophilic bacterium, characterized as Pantoea agglomerans D23W3, from contaminated soils collected from refinery has been reported. HPLC analysis revealed that P. agglomerans D23W3 could convert DBT to 2-hydroxybiphenyl (2-HBP) via the 4S pathway and that it could degrade 93% of the 100 ppm DBT within 24 h of culture. In addition P. agglomerans D23W3 could also desulfurize 4,6-dimethyl DBT and benzothiophene which are among the most difficult DBT derivatives to be removed by HDS. Further, adapted cells of P. agglomerans D23W3 were found to remove 26.38-71.42% of sulfur from different petroleum oils with highest sulfur removal from light crude oil. Therefore, P. agglomerans D23W3 has a potential for the BDS of the petroleum oils. (C) 2010 Elsevier B.V. All rights reserved.