Ruiz-Matute A I, Sanz M L, Corzo N, Martín-Alvarez P J, Ibañez E, Martínez-Castro I, Olano A
Instituto de Química OrgAnica General, C.S.I.C., Juan de al Cierva, 3 28006 Madrid, Spain.
J Agric Food Chem. 2007 May 2;55(9):3346-50. doi: 10.1021/jf070018u. Epub 2007 Mar 30.
The viability of the purification of lactulose from a mixture with lactose [70:30 (w/w)] using pressurized liquid extraction (PLE) at 1500 psi for 30 min was studied. Different temperatures (from 40 to 130 degrees C) and proportions of ethanol:water (70:30, 80:20, 90:10, 95:5, and 100:0) as the extraction solvent were assayed. Lactose and lactulose were measured by gas chromatographic analysis as their trimethylsilyl derivatives. Data were fitted through multiple linear regressions to different quadratic models to describe both the extraction yield (in terms of mg of lactulose) and the purity of the lactulose extracted. The optimum extraction conditions provided by the model were as follows: extraction temperature, 40 degrees C; and solvent composition, 70:30 ethanol:water. PLE extraction under the optimized conditions was also applied to purify lactulose from lactose in a synthesis mixture. To our knowledge, this is the first time that PLE has been tested for extraction and purification of lactulose from its mixture with lactose; this technique showed several advantages over classical methods such as the short extraction time and the low solvent consumption.
研究了在1500磅力/平方英寸的压力下使用加压液体萃取（PLE）30分钟从乳糖混合物[70:30（w/w）]中纯化乳果糖的可行性。测定了不同温度（40至130摄氏度）以及乙醇与水的不同比例（70:30、80:20、90:10、95:5和100:0）作为萃取溶剂的情况。乳糖和乳果糖通过气相色谱分析其三甲硅烷基衍生物进行测定。数据通过多元线性回归拟合到不同的二次模型，以描述萃取产率（以乳果糖毫克数计）和所萃取乳果糖的纯度。该模型提供的最佳萃取条件如下：萃取温度40摄氏度；溶剂组成，70:30乙醇:水。优化条件下的PLE萃取也应用于从合成混合物中的乳糖中纯化乳果糖。据我们所知，这是首次测试PLE从其与乳糖的混合物中萃取和纯化乳果糖；该技术相对于传统方法显示出几个优点，如萃取时间短和溶剂消耗低。
