Assessment of Peptides and Membrane Physico-Chemical Characteristics on Migration Selectivity and Recovery of Antimicrobial Fractions Using Electrodialysis with Ultrafiltration Membrane on a Calf Cruor Hydrolysate

In recent years, cruor from slaughterhouse blood has garnered growing interest as a potential source of antimicrobial peptides obtained through enzymatic hydrolysis. In addition, electrodialysis with ultrafiltration membrane (EDUF) represents a strategy for valorizing peptide-rich hydrolysates, enabling the selective separation and concentration of antimicrobial peptides, according to their size and charge. Hence, this study evaluated the potential of EDUF to fractionate, for the first time, calf cruor hydrolysate and explore its use as a novel source of antimicrobial peptides. The resulting peptide fractions were characterized to investigate the selectivity of peptide migration in relation to peptide physico-chemical characteristics and membrane properties and to finally assess their antimicrobial activity. High migration rates of 12.75 ± 2.17 g/m2h and 8.94 ± 0.38 g/m2h were observed for the cationic (P+) and anionic (P−) recovery fractions, respectively. These results suggested that peptide migration from calf cruor hydrolysate to both recovery fractions during EDUF was influenced by the combined effects of molecular weight, net charge, hydrophobicity, specific amino acid residues (L, Y), and peptide–membrane interactions. Furthermore, the initial and final hydrolysates as well as P+ fractions exhibited antifungal activities against Paecilomyces spp. and Rhodotorula mucilaginosa with minimum inhibitory concentrations (MIC) ranging from 0.312 to 0.615 mg/mL and minimum fungicidal concentrations (MFCs) ranging from 0.312 to 1.250 mg/mL. In contrast, the P− fraction did not exhibit antifungal activity, but a slight anti-Listeria activity was detected, with a MIC of 10 mg/mL. These findings highlight the potential of upcycling calf blood into functional antifungal and antibacterial agents, supporting a circular economy approach and transforming waste streams into value-added ingredients that enhance food preservation.