Activity-guided peptidomic and metabolomic characterization of egg yolk plasma fractions with antimicrobial properties against foodborne pathogens

Antimicrobial compounds are important for food safety, shelf-life extension, and quality preservation. Hen egg yolk is a rich but underexplored source of such bioactive molecules. In this study, water-soluble egg yolk plasma components were separated by reversed-phase HPLC into 47 fractions and screened for antimicrobial activity. Two early-eluting fractions (1Y and 2Y) exhibited strong bactericidal effects against Pseudomonas fluorescens BF13, while only fraction 2Y was active against Listeria monocytogenes SA, reducing viable cells by more than 5log₁₀ CFU/mL after 1 h. Integrated peptidomic and metabolomic analyses revealed endogenous glycosylated peptides mainly derived from vitellogenin-2 together with low-molecular-weight metabolites, including amino acids, γ-glutamyl peptides, sugar derivatives, pantothenic acid-related compounds, and Maillard-type conjugates. Comparative profiling highlighted compositional differences between 1Y and 2Y that may contribute to their distinct antimicrobial spectra. These findings identify egg yolk plasma as a source of antimicrobial fractions with potential relevance for food preservation applications.