Valorization of turkey cruor through peptic hydrolysis: peptidomic and machine learning approaches for the identification of antimicrobial peptides.

The slaughterhouse blood remains an underexploited by-product with promising potential for producing natural antimicrobial agents. This study investigated the hydrolysis of turkey cruor with pepsin under varying durations, as well as the impact of discoloration on the peptide population and antimicrobial activities. The discoloration at pH 4 effectively removed heme and enhanced antifungal and anti-yeast activities, particularly against Rhodotorula mucilaginosa, Paecilomyces spp., and Mucor racemosus. Comparative peptidomics combined with partial least squares-discriminant analysis enabled the identification of potential peptide sequences associated with antifungal and anti-yeast activities. Twenty-four peptides were synthesized, of which eleven showed strong fungicidal activity. The active peptides shared physicochemical characteristics, including a net positive charge and amphipathicity, which facilitated effective membrane targeting. Overall, these findings highlight turkey cruor as a valuable source of antifungal and anti-yeast peptides and demonstrate the efficiency of integrating peptidomics with machine learning to discover new bioactive peptides.