• Food Science of Animal Resources
• /
• v.42 no.3
• /
• pp.351-371
• /
• 2022

Milk fats are present as globules emulsified in the aqueous phase of milk and stabilized by a delicate membrane architecture called milk fat globule membrane (MFGM). The unique structure and composition of the MFGM play an important role in fat digestion and the metabolic programming of neonates. The objective of this review is to compare the structure, composition, and physicochemical characteristics of fat globules in human milk, bovine milk, and infant formula. It provides an overview of the fat digestion process and enzymes in healthy infants, and describes the possible roles of the MFGM in association with factors affecting fat digestion. Lastly, the health benefits of the MFGM on infant nutrition and future perspectives are discussed with a focus on brain development, metabolic response, and gut health.

• Journal of Dairy Science and Biotechnology
• /
• v.21 no.2
• /
• pp.138-147
• /
• 2003

We here analyzed and proposed the structures of the N-linked sugar chains of PAS-7 from bovine milk fat globule membrane. The N-linked sugar chains were liberated from PAS-7 by hydrazinolysis and, after modifying the reducing ends with 2-aminopyridine (PA), were separated into one neutral (7N,55%) and two acidic (7M mono-, 43%; 7D, di-, 2%) sugar chain roups. The latter were converted into neutral groups (7MN and 7DN) by sialidase digestion. The structure of each of these PA-neutral sugar chains was determined by sugar analysis, sequential exoglycosidase digestion, partial acetolysis, and 1H-NMR spectroscopy. The results show that the 10 sugar chains were of the biantennary complex type with and without fucose. The structure of 7N2A one of the major sugar chains, was proposed as; [structure: see text] A structural comparison between PAS-6 and -7 indicated that although they shared the same protein core, their sugar moiety was markedly different, involving the existence of a different pathway during the post-transcriptional modification.

• Korean Journal of Food Science and Technology
• /
• v.21 no.5
• /
• pp.726-734
• /
• 1989

To analyze the components of dense coat fractions associated with fat globule membrane, The membrane was treated with various concentrations of Triton X-100, a non-ionic detergent, and the composition of lipids associated to the detergent insoluble material was analyzed. The amount of protein, phospholipid, cholesterol and ganglioside in milk fat globule membrane was reduced consistently with increasing concentrations of Triton X-100. Butyrophilin (band 12), xanthine oxidase (band 3) and band 16 as constituents of insoluble coat materials was revealed after electrophorisis on SDS-polyacrylamide gels. Phosphatidyl ethanolamine, phosphatidyl choline, phosphatidyl serine, phosphatidyl inositol and sphingomyelin were identified as the major phospholipids of the coat materials without selective concentration relative to the original membranes. Percentages of total phospholipid were not changed by any of the treatments. Fatty acids of total lipid were myristate, palmitate, stearate (major saturated acids), oleate and linoleate (major unsaturated acids). Cholesterol contents on a protein basis were slightly reduced with increasing concentrations of Triton X-100. Cholesterol adhered to protein more tightly than other constituents The contents of gangliosides was proportionally refuted with increasing concentration of Triton X-100.

• Food Science of Animal Resources
• /
• v.21 no.4
• /
• pp.367-373
• /
• 2001

Glycoproteins PAS-6(50 kDa) and -7(47 kDa) from the bovine milk fat globule membrane share a common protein core but differ in their carbohydrate moiety. We have analyzed and proposed the structures of the N-linked sugar chains of PAS-7 by Oxford Glyco System(OGS) RAAM2000. The N-linked sugar chains were liberated from PAS-7 by hydrazinolysis and, after modifying the reducing ends with 2-aminobenzamide(2-AB), were separated into one neutral(7N, 55%) and two acidic(7M, mono-, 43%; 7D, di-, 2%) sugar chain groups. 7N was finally separated into 5 chains(a, b, c, d, and e), respectively. The structure of this 2AB-neutral sugar chain was determined by sugar analysis, exoglycosidase digestion with OGS glycosidase Kit and OGS RAAM2000 system. The results show that fraction e was the same of reported 7N1A, the biantennary complex type with a fucose on reducing end and two N-acetyllactosamine branch on non-reducing end. Therefore, it was proved that OGS RAAM2000 method is in conformity with conventional analysis of sugar chain structure from bovine PAS-7.