Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China.
Biodegradation. 2010 Nov;21(6):1057-66. doi: 10.1007/s10532-010-9366-8. Epub 2010 May 14.
In the present study, a new bacterial strain isolated from activated sludge has been identified as Lysinibacillus sphaericus based on its morphology, physiochemical properties, and the results of 16S ribosomal RNA (rRNA) gene sequence analysis. This new bacterial strain uses ethanethiol as both carbon source and energy source. The key factors for controlling the degradation efficiency of ethanethiol by this strain were found to be initial ethanethiol concentration, temperature, and pH value of solutions. Under the optimized conditions, as well as 4 mg l(-1) ethanethiol, 30°C, and pH = 7.0, almost 100% ethanethiol can be degraded within 96 h and sulfate as a final product was detected in aqueous medium. The degradation reaction of ethanethiol over this newly isolated strain can be described by pseudo first-order equation in which the maximum degradation rate constant K and the minimum half-life were respectively calculated to be 0.0308 h(-1) and 22.5 h under the optimal conditions.
在本研究中，从活性污泥中分离出的一株新细菌菌株，根据其形态、理化特性和 16S 核糖体 RNA(rRNA)基因序列分析结果，被鉴定为球形赖氨酸芽孢杆菌。该新细菌菌株以乙硫醇作为碳源和能源。发现控制该菌株降解乙硫醇效率的关键因素是初始乙硫醇浓度、温度和溶液的 pH 值。在优化条件下，以及 4mg/L 乙硫醇、30°C 和 pH=7.0 下，乙硫醇几乎可以在 96h 内完全降解，并且在水介质中检测到硫酸根作为最终产物。乙硫醇在新分离的菌株上的降解反应可以用拟一级方程来描述，其中在最佳条件下，最大降解速率常数 K 和最小半衰期分别计算为 0.0308/h 和 22.5h。
