Open AccessThermophilic biodesulfurization of hydrodesulfurized light gas oils by Mycobacterium phlei WU‐F1
Author(s) -
Furuya Toshiki,
Ishii Yoshitaka,
Noda Kenichi,
Kino Kuniki,
Kirimura Kohtaro
Publication year - 2003
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1016/s0378-1097(03)00169-1
Subject(s) - mycobacterium phlei , thermophile , chemistry , mycobacterium , microbiology and biotechnology , food science , biology , bacteria , biochemistry , genetics , enzyme
Recalcitrant organosulfur compounds such as dibenzothiophene (DBT) derivatives in light gas oil (LGO) cannot be removed by conventional hydrodesulfurization (HDS) treatment using metallic catalysts. The thermophilic DBT‐desulfurizing bacterium Mycobacterium phlei WU‐F1 grew in a medium with hydrodesulfurized LGO as the sole source of sulfur, and exhibited high desulfurizing ability toward LGO between 30 and 50°C. When WU‐F1 was cultivated at 45°C with B‐LGO (390 ppm S), F‐LGO (120 ppm S) or X‐LGO (34 ppm S) as the sole source of sulfur, biodesulfurization resulted in around 60–70% reduction of sulfur content for all three types of hydrodesulfurized LGOs. In addition, when resting cells were incubated at 45°C with hydrodesulfurized LGOs in the reaction mixtures containing 50% (v/v) oils, biodesulfurization reduced the sulfur content from 390 to 100 ppm S (B‐LGO), from 120 to 42 ppm S (F‐LGO) and from 34 to 15 ppm S (X‐LGO). Gas chromatography analysis with an atomic emission detector revealed that the peaks of alkylated DBTs including 4‐methyl‐DBT, 4,6‐dimethyl‐DBT and 3,4,6‐trimethyl‐DBT significantly decreased after biodesulfurization. Therefore, thermophilic M. phlei WU‐F1, which could effectively desulfurize HDS‐treated LGOs over a wide temperature range up to 50°C, may be a promising biocatalyst for practical biodesulfurization of diesel oil.