title: Deep desulfurization of hydrodesulfurization-treated diesel oil by a facultative thermophilic bacterium Mycobacterium sp. X7B.
abstract: The dibenzothiophene (DBT) desulfurization pathway of a facultative thermophilic bacterium Mycobacterium sp. X7B was investigated. Metabolites were identified by gas chromatography-mass spectrometry, and the results showed that 2-hydroxybiphenyl, the end product of the previously reported sulfur-specific pathway (also called 4S pathway), was further converted to 2-methoxybiphenyl. This is the first strain to possess this ability and therefore, an extended 4S pathway was determined. In addition, the DBT-desulfurizing bacterium Mycobacterium sp. X7B was able to grow on DBT derivatives such as 4-methylDBT and 4,6-dimethylDBT. Resting cells could desulfurize diesel oil (total sulfur, 535 ppm) after hydrodesulfurization. GC flame ionization detection and GC atomic emission detection analyses were used to qualitatively evaluate the effect of Mycobacterium sp. X7B treatment on the content of the diesel oil. The total sulfur content of the diesel oil was reduced 86% using resting cell biocatalysts for 24 h at 45 degrees C.
authors.affiliation: State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, PR China.
authors.forename: Fu Li
authors.initials: FL
authors.lastname: Li
authors.forename: Ping
authors.initials: P
authors.lastname: Xu
authors.forename: Cui Qing
authors.initials: CQ
authors.lastname: Ma
authors.forename: Lai Long
authors.initials: LL
authors.lastname: Luo
authors.forename: Xiao Shan
authors.initials: XS
authors.lastname: Wang
mesh_terms: D000393:Air Pollutants / Q000378:metabolism; D001713:Biphenyl Compounds / Q000378:metabolism; D005648:Fuel Oils / Q000382:microbiology*; D008401:Gas Chromatography-Mass Spectrometry; D005742:Gasoline / Q000382:microbiology*; D009161:Mycobacterium / Q000378:metabolism*; D013455:Sulfur / Q000378:metabolism*
chemical_list: D000393:Air Pollutants; D001713:Biphenyl Compounds; D005648:Fuel Oils; D005742:Gasoline; D013455:Sulfur; C004369:2-phenylphenol