Isolation and Characterization of Chicken Yolk Vitelline Membrane Lipids Using Eggs Enriched With Conjugated Linoleic Acid

Abstract

The vitelline membrane (VM) encloses the chicken egg yolk, separating it from albumen. The VM weakens during storage, and dietary lipid modification significantly affects its strength. However, no studies have characterize the fatty acyl residue (FA) composition of the VM, and reports of VM isolation and quantified lipid content are inconsistent. Therefore, the objectives of this study were: (1) to develop a washing and isolation method that removes residual yolk from VM without damage; (2) to determine the FA and lipid composition of CLA-rich egg yolk VM, relative to controls; (3) to determine the effect of 20 days of refrigeration on VM FA and lipid composition. To determine VM FA and lipid composition, 36 hens received either a corn-soybean meal-based control diet ("Control"), or the Control supplemented with either 10 % soy oil ("Soy control"), or 10 % CLA-rich soy oil ("CLA") for 30 days. VM were analyzed the day of collection ("fresh"), or after 20 days of refrigeration ("refrigerated"). There were no differences in FA compositions of fresh and refrigerated membranes within a treatment. CLA-rich yolk VM contains CLA, greater SFA, and significantly greater DHA relative to controls. Direct MALDI-TOF-MS identified 15 phosphatidylcholines, three phosphatidylethanolamines, one sphingomyelin, and 15 triacylglycerols in VM. Lipid species that showed significant differences among egg types included nine phosphatidylcholines and six triacylglycerols. MALDI analysis indicated significant differences in nine lipid classes on the VM inner layer. After refrigeration, five lipid classes on the inner layer and seven lipid classes on the outer layer had statistically significant differences among VM types.

Comparative N-Glycoproteomic Analysis Provides Novel Insights into the Deterioration Mechanisms in Chicken Egg Vitelline Membrane during High-Temperature Storage

“…These proteins involved in lipid binding contained apolipoprotein B, ovocleidin-17, BPI2 domain-containing protein, and the Joining chain of multimeric IgA and IgM. It prompted us to pay attention to the effects of N-glycosylation on lipid distribution or structure in CEVM because lipid content modifications in CEVM significantly affected the strength of CEVM . Glycosaminoglycans, as one of the extracellular matrix components, were believed to affect the rate of fibril formation and fibril diameter .…”

“…It prompted us to pay attention to the effects of N-glycosylation on lipid distribution or structure in CEVM because lipid content modifications in CEVM significantly affected the strength of CEVM. 23 Glycosaminoglycans, as one of the extracellular matrix components, were believed to affect the rate of fibril formation and fibril diameter. 24 Thus, the glycosaminoglycan binding proteins, including apolipoprotein B, ovocleidin-17, and the Joining chain of multimeric IgA and IgM, may play important roles in the CEVM structure.…”

The Golden Egg: Nutritional Value, Bioactivities, and Emerging Benefits for Human Health

“…The total lipid content is relatively stable in the egg ranging from 8.7 to 11.2 per 100 g of whole egg, when considering various EU countries and USA egg composition tables [29]. These lipids are only concentrated in the egg yolk (Figure 2 and Table 1) and a small part may remain tightly associated with vitelline membranes [48,49].…”

Matrix‐assisted ionization Fourier transform mass spectrometry for the analysis of lipids

“…MAI‐FTMS spectra of polar lipids were also compared with previous MALDI and ESI results 16 . About two‐thirds of the lipids in egg yolk are non‐polar and the remainder are polar 17 . The most important polar lipids in egg yolk are phosphatidylcholine and phosphatidylethanolamine.…”