Selective-desulfurization of dibenzothiophene by Microbacterium sp. ZD-M2 and optimization of growth conditions
A newly isolated strain was identified as Microbacterium sp. ZD-M2, which can specifically remove sulfur from the model compound of dibenzothiophene (DBT). 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. Biphenyl) was also produced as the deoxidized metabolites. In aqueous phase the strain grew well in the pH range of 6.5—9.5.The optimal temperature for growth was 30 ℃ and the appropriate concentration of ammonium chloride as the source of nitrogen was 1.0 g·L~(-1). Glycerol and DBT were selected as the best carbon and sulfur sources for its growth, and the optimal concentrations were 2.0 g·L~(-1) and 0.2 mmol·L~(-1),respectively.