The milk fat globule membrane: A potential source of health-promoting glycans

The milk fat globule membrane that surrounds the lipid globules in milk is assembled and secreted by the epithelial cells of the mammary gland and consists of a complex mixture of proteins, enzymes, glycoproteins, neutral lipids, polar lipids, and glycolipids. Many nutritional and health-promoting properties have been linked with these MFGM components including anticarcinogenic and anticholesterol activity as well as improving long-term memory. Glycosylated MFGM proteins and lipids, in particular, have been credited with a number of health-promoting properties. For instance, these glycoconjugates are thought to act as specific bacterial and viral ligands, which, when present in the gastrointestinal tract of young mammals, contribute to the prevention of infection. MFGM glycoproteins have also been linked with the prevention of inflammatory diseases such as multiple sclerosis. In this chapter, we provide an overview of the composition, structure, and biological activities of glycosylated MFGM compounds sourced from various mammalian milks, using human MFGM for comparative purposes. We also discuss the potential use of MFGM as a source of health-promoting glycans that could be incorporated into functional foods.