Abstract: Egg yolk lecithin is a natural animal-derived phospholipid complex, primarily composed of phosphatidylcholine, phosphatidylethanolamine, sphingomyelin, lysophosphatidylcholine, and lysophosphatidylethanolamine, and has multiple bioactivities such as neuroprotection, hepatoprotection, anti-aging, and immunomodulation. Techniques such as solvent extraction, supercritical fluid extraction, membrane separation and column chromatography can effectively isolate lecithin from egg yolk, and the lecithin can be precisely characterized by mass spectrometry (MS)-based lipidomics. Egg yolk lecithin, a unique amphiphilic substance containing a hydrophilic polar phosphate head and a hydrophobic tail consisting of fatty acid chains, can form bilayer vesicles, making it suitable for encapsulating sensitive active substances or small molecule drugs to improve their bioavailability. The application scope of egg yolk lecithin has expanded from traditional foods to high-value-added pharmaceuticals, health foods and cosmetics, showing significant development potential. This article systematically reviews the structural characteristics, extraction and identification methods, bioactivities, and applications of egg yolk lecithin, with a view to providing a theoretical reference for its future research and high-value-added application.

Key words: egg yolk lecithin; structural characterization; extraction and identification; bioactivities; applications