Ralstonia eutropha as a biocatalyst for desulfurization of dibenzothiophene
Ralstonia eutropha as a biocatalyst for desulfurization of dibenzothiophene
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DOI：
10.1007/s00449-017-1760-8
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发表时间：
2017-07-01
影响因子：
3.8
通讯作者：
Habibi, Alireza
中科院分区：
文献类型：
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作者：
Dejaloud, Azita;Vahabzadeh, Farzaneh;Habibi, Alireza
在生长和静止细胞条件下研究了富养罗尔斯通氏菌作为二苯并噻吩（DBT）脱硫生物催化剂的潜力。结果表明，DBT在脱硫的同时生成了2-羟基联苯（2-HBP）。在生长细胞实验中，葡萄糖被用作初始浓度为55 mM（能量有限）和111 mM（能量充足）的能量供应底物。利用逻辑斯蒂方程和维持概念定量描述了细胞的生长行为。结果表明，能量充足的培养基2-HBP产量较高，但比生长速率和维持系数低于能量受限的培养基。此外，动力学研究表明，半饱和常数的能量有限的培养物是2倍高的能量充足的抑制常数（0.08 mM）和最大比DBT脱硫速率（0.002 mmol g（细胞）（-1）h（-1））几乎是恒定的。通过定义包括生物量浓度和达到特定DBT转化百分比的时间的生物量容量（D（DBT）），确定了23%g（cell）L-1 h（-1）的最佳条件，其对应于在指数生长中期收获的静息细胞。
The potential of Ralstonia eutropha as a biocatalyst for desulfurization of dibenzothiophene (DBT) was studied in growing and resting cell conditions. The results of both conditions showed that sulfur was removed from DBT which accompanied by the formation of 2-hydroxybiphenyl (2-HBP). In growing cell experiments, glucose was used as an energy supplying substrate in initial concentrations of 55 mM (energy-limited) and 111 mM (energy-sufficient). The growing cell behaviors were quantitatively described using the logistic equation and maintenance concept. The results indicated that 2-HBP production was higher for the energy-sufficient cultures, while the values of the specific growth rate and the maintenance coefficient for these media were lower than those of the energy-limited cultures. Additionally, the kinetic studies showed that the half-saturation constant for the energy-limited cultures was 2 times higher than the energy-sufficient ones where the inhibition constant (0.08 mM) and the maximum specific DBT desulfurization rate (0.002 mmol g(cell) (-1) h(-1)) were almost constant. By defining desulfurizing capacity (D (DBT)) including both the biomass concentration and time to reach a particular percentage of DBT conversion, the best condition for desulfurizing cell was determined at 23% g(cell) L-1 h(-1) which corresponded with the resting cells that were harvested at the mid-exponential growth phase.