母乳中1,3-二不饱和脂肪酸-2-棕榈酸甘油三酯的组成及其功能特性研究进展Composition of 1,3-diunsaturated fatty acid-2-palmitin triacylglycerols in human milk and their functions: a review

1,3-二不饱和脂肪酸-2-棕榈酸甘油三酯（UPU）是指甘油骨架的sn-1、sn-3位连接不饱和脂肪酸、sn-2位连接棕榈酸的一类甘油三酯的总称，其在母乳脂肪中含量最高，可为婴儿提供更加均衡的脂肪酸和甘油三酯，对婴儿生长发育有特殊的生理功能。为对开发新型母乳结构脂肪提供理论支持，系统介绍了不同国家、地区母乳脂肪中3种sn-2棕榈酸甘油三酯UPU、UPS、SPS的含量，我国成熟期母乳中UPU的组成和含量，从降低婴儿粪便硬度、促进脂肪和矿物质吸收、保护肠道健康，提供更多种类、比例更稳定均衡的脂肪酸等方面，论述了UPU的功能作用及其消化和吸收特性，另外对比了市售营养强化剂OPO与母乳中UPU组成的差异，通过分析提出LC-MS方法更适合婴儿配方奶粉中OPO含量的测定。 1,3-Diunsaturated fatty acid-2-palmitin triacylglycerols (UPU) are the triacylglycerols that unsaturated fatty acids combined at sn-1 or 3 position, and palmitic acid located at the sn-2 position. UPU has the highest content in human milk fat, providing infant balanced fatty acids and triacylglycerols which are important for infant growth. In order to provide the scientific basis for the development of novel human milk fat substitutes, the contents of three sn-2 palmitate triglycerides UPU, UPS and SPS in human milk fat in different countries and regions, and the composition and contents of UPU in maturing human milk in China were systematically introduced, the function of UPU in terms of reducing fecal hardness, promoting fat and mineral absorption, protecting intestinal health of infants, providing a wider variety of fatty acids in a more stable and balanced ratio, and its digestive and absorption properties were discussed, and the differences in the composition of commercially available nutritional fortifier OPO and UPU in human milk were compared.The LC-MS method was proposed to be more suitable for the determination of OPO content in infant formula.