红串红球菌USTB-03对4,6-二甲基二苯并噻吩的脱硫研究

Biodesulfurization of 4, 6-dimethyl Dibenzothiophene by Rhodococcus Erythropolis USTB-03

分离出1株能够对4,6-二甲基二苯并噻吩(4,6-DMDBT)进行高效脱硫的微生物菌种,经中国科学院微生物研究所鉴定为红串红球菌USTB-03。研究结果表明,与甘油和乙醇相比,葡萄糖是促进红串红球菌USTB-03生长和提高其脱硫比活性的最好碳源,最高脱硫比活性可达298.1mmol4,6-DMDBT/(kg·h)。在初始pH从4.0到9.0范围内,pH7.0可以使红串红球菌USTB-03保持最大的脱硫比活性。进一步研究显示,红串红球菌USTB-03对4,6-DMDBT脱硫后的最终代谢产物是3,3-二甲基-2-羟基联苯(2-HDMBP),只有C-S键被切断,而C-C键未受到破坏。该脱硫途径类似于二苯并噻吩(DBT)特异性脱硫的途径。

A bacterial strain that has a strong ability in the biodesulfurization of 4,6-dimethyl dibenzothiophene （4,6-DMDBT） was isolated and identified as Rhodococcus erythropolis USTB-03 by Institute of Microbiology, Chinese Academy of Sciences. Compared with glycerol and ethanol tested, glucose was found to be a promising sole carbon source for both the growth and the biodesulfurization activity of R, erythropolis USTB-03, and the maximum specific activity of 4,6-DMDBT biodesulfurization was 298.1 mmol 4,6-DMDBT/（kg ·h）. It showed that the highest biodesulfurization activity of R. erythropolis USTB-03 was found at initial pH 7.0 in range from 4.0 to 9.0. R. erythropolis USTB-03 can selectively remove sulfur in the 4,6-DMDBT, and the dead-end product of 4, 6-DMDBT biodesulfurization was confirmed as 2-hydroxy- 3, 3＇-dimethyl biphenyl （2-HDMBP）, only the bond of C-S rather than C-C was cleaved, which is similar to the sulfur specific biodesuffufization pathway of dibenzothiophene.