Huang Xiang-Feng, Zhang Shu-Cong, Peng Kai-Ming, Lu Li-Jun, Liu Jia
State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
Huan Jing Ke Xue. 2013 Jul;34(7):2906-11.
Extraction and identification of surface active substance of Alcaligenes sp. S-XJ-1, as well as description of its emulsion breaking process were conducted to reveal the demulsifying characteristics of this demulsifying strain. Alkali solvent was adopted in the extraction process with conditions optimized as 35 degrees C, 0.08 mol x L(-1) of alkali concentration, 12 g x L(-1) of sample to solution ratio, and 4 h of extraction time by launching both single-factor and orthogonal tests. Under this optimal condition, the extracted surface active substance (the extraction ratio was 36.1%) achieved 77% emulsion breaking ratio for 500 mg x L(-1) within 48 h. FT-IR showed the existence of glycolipids, lipids and proteins in the surface active substance, the molecular weight of which mainly scattered between 55 and 61 256. Saccharides, lipids and proteins were identified as the three chief components in surface active substance with the content of 22.2%, 7.5% and 13.4%, respectively. The proteins were further proved to take the most responsibility for the emulsion breaking ability. Moreover, obvious difference in the emulsion breaking process was demonstrated between the original demulsifying strain S-XJ-1 and the extracted surface active substance by real time observation of Turbiscan Lab Expert. The results suggested that the demulsifying efficiency of the strain was jointly contributed by its surface active substance and demulsifying cell morphology, and the former possessed higher functional priority than the latter.
对产碱杆菌属S-XJ-1的表面活性物质进行提取与鉴定，并描述其破乳过程，以揭示该破乳菌株的破乳特性。提取过程采用碱溶剂，通过单因素试验和正交试验优化条件为35℃、碱浓度0.08 mol·L⁻¹、样品与溶液比例12 g·L⁻¹、提取时间4 h。在此最佳条件下，提取的表面活性物质（提取率为36.1%）在48 h内对500 mg·L⁻¹的乳液破乳率达到77%。傅里叶变换红外光谱显示表面活性物质中存在糖脂、脂类和蛋白质，其分子量主要分布在55至61 256之间。糖类、脂类和蛋白质被鉴定为表面活性物质的三种主要成分，含量分别为22.2%、7.5%和13.4%。进一步证明蛋白质对破乳能力起主要作用。此外，通过Turbiscan Lab Expert实时观察，原破乳菌株S-XJ-1与提取的表面活性物质在破乳过程中表现出明显差异。结果表明，该菌株的破乳效率是由其表面活性物质和破乳细胞形态共同作用的，且前者比后者具有更高的功能优先级。
