中文摘要：

对胞壁结合型生物破乳菌 Alcaligenes sp. S-XJ-1的表面破乳活性物质进行提取和初步鉴定,并探讨了菌体和表面活性物质的破乳过程,以揭示生物破乳菌的破乳特性. 采用碱液提取破乳菌表面活性物质,并通过单因素试验和正交试验得到最优提取条件：温度35℃、碱液浓度0.08 mol·L-1、料液比12 g·L-1、提取时间4 h,在此条件下提取率为36.1%, 500 mg·L-1破乳菌表面活性物质48 h破乳率为77%; 采用凝胶过滤色谱和红外光谱对破乳菌表面活性物质的分子量和表面基团进行分析,发现其相对分子质量分布于55~61256,表面存在糖脂类、脂类和蛋白类物质的特征基团; 成分分析表明破乳菌表面活性物质含糖类、脂类和蛋白类分别为22.2%、7.5%和13.4%. 胰蛋白酶处理破乳菌表面活性物质几乎使其完全丧失破乳活性,表明蛋白类物质是其破乳活性的关键因素. 使用稳定性分析仪对破乳菌菌体和表面活性物质的破乳过程进行分析,发现二者破乳过程有较大差异,菌体表面活性物质是菌体破乳活性的主要来源,菌体表面结构在破乳过程中起辅助作用,菌体的破乳性能是破乳活性物质和菌体形态共同作用的结果.

英文摘要：

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℃, 0.08 mol·L-1 of alkali concentration, 12 g·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·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 61256. 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.