Desulfurization of dibenzothiophene derivatives by whole cells ofRhodococcus erythropolisH-2

The dibenzothiophene desulfurizing bacterium, Rhodococcus erythropolis H-2, could grow on dibenzothiophene derivatives such as 3,4-benzodibenzothiophene, 2,8-dimethyldibenzothiophene and 4,6-dimethyldibenzothiophene as sulfur sources. Using whole cells, the structurally asymmetric dibenzothiophene derivative 3,4-benzodibenzothiophene, added at 1 mM, was completely degraded within 12 h. The reaction product from 3,4-benzodibenzothiophene was identified as an α-hydroxy-β-phenylnaphthalene by gas chromatography-mass spectrometry and nuclear magnetic resonance analyses. The reaction products from structurally symmetrical 2,8- and 4,6-dimethyldibenzothiophenes were also identified as the corresponding monohydroxy dimethyl biphenyls. The initial reaction rates for 2,8-dimethyldibenzothiophene, 4,6-dimethyldibenzothiophene and 3,4-benzodibenzothiophene were about 120, 60 and 20% that of dibenzothiophene.