米酒乳杆菌素分离纯化条件研究

目的：对米酒乳杆菌产生的广谱细菌素进行分离纯化技术研究。方法和结果：采用活性炭脱色、冷乙醇沉淀、Sephadex G50 葡聚糖凝胶层析和高效液相色谱技术对米酒乳杆菌产生的细菌素进行分离纯化。结果表明，发酵浓缩液脱色的最佳工艺条件为活性炭加量3.5%、温度40℃、脱色时间20h，脱色率达64.5%。冷乙醇沉淀的最佳乙醇终浓度为80%，葡聚糖凝胶层析的洗脱液流速为0.5ml/min，上样量3ml，高效液相色谱纯化的流动相为90% 的甲醇水溶液，在此条件下可得到电泳纯的细菌素。结论：确定了米酒乳杆菌素的分离纯化条件，为细菌素的理化性质和抑菌机理的研究提供依据。

Study on Isolation and Purification Technology of Sakacin from Fermentation Broth of Lactobacillus sake G2

Objective: To study the isolation and purification technology of a broad-spectrum bacteriocin, sakacin produced by Lactobacillus sake G2. Methods: The cell-free fermentation broth of Lactobacillus sake G2 containing sakacin was decolored with active carbon and precipitated with cold ethanol to remove macromolecular impurities, and purified by Sephadex G50 column chromatography and HPLC. Results: The optimum conditions for isolation and purification were as follows: decoloring the cell-free supernatant of Lactobacillus sake G2 with 3.5% of active carbon addition at 40 ℃ for 20 h (the decolorization rate reached 64.5%), finial ethanol concentration 80%, elution flow rate of Sephadex G50 column 0.5 ml/min, sampling volume 3 ml, and taking 90% methanol aqueous solution as mobile phase for HPLC. Under these conditions, the electrophoretic purity of sakacin was obtained. Conclusions: This study can lay the foundation for the future study of physicochemical properties and bacteriostatic mechanism of sakacin.