基于一步法萃取婴幼儿奶粉中游离态叶黄素和β-胡萝卜素研究

One-Step Extraction of Free Lutein and β-Carotene from Infant Formula

为建立简单、快速、准确的样品前处理方法以提高婴幼儿奶粉中叶黄素和β-胡萝卜素的提取效率,通过显微镜观察奶粉样品中叶黄素包埋剂的溶解特性,采用有机溶剂一步萃取的方式替代传统耗时的皂化法.样品加水破除包埋剂,后续经乙醇溶解剩余被脂类成分包裹的包埋剂并沉淀蛋白,再用甲基叔丁基醚在单相中一步萃取叶黄素和β-胡萝卜素,方法无需浓缩,适用于高效液相色谱直接分析.结果表明,游离态叶黄素和β-胡萝卜素的线性相关系数均为0.999 9,加标回收率为91%~94%,且所有RSD<5%.

We report, in this work, the establishment of a simple, rapid and accurate sample pretreatment method to improve the extraction efficiency of lutein and β-carotene in infant milk powder. To replace the time-con-suming saponification method, dynamic dissolution processes of different solvents for embedding materials of lutein and simultaneous extraction of lutein and β-carotene by organic solvents were inspected using a microscope. Using water to dissolve the embedding material to free lutein and β-carotene and ethanol to precipitate proteins, we show that the sample can be extracted by methyl tert-butyl ether in monophase. After that, the extraction solution could be analyzed by HPLC without concentration. The calibration curve of free lutein and β-carotene exhibited good line-arity, with both r2 equal to 0. 999 9. Recoveries ranged from 91% to 94% , and relative standard deviations （RSDs） are less than 5% .