Structural and Functıonal Characterızatıon of an Alcalase-Derıved Proteın Hydrolysate from Rapana Venosa for Functıonal Food Applıcatıons With Elemental Safety Assessment

Abstract Rapana venosa is a benthic marine gastropod with high protein content; however, its use as a food-derived protein source is limited by concerns regarding potentially toxic elements. In this study, a protein hydrolysate was produced from R. venosa muscle using Alcalase and characterized in terms of structural, functional, and elemental properties. The hydrolysate showed a high degree of hydrolysis (55.5%), supported by amino acid profiling and SDS-PAGE analysis indicating the predominance of low-molecular-weight peptides. The amino acid composition revealed a substantial proportion of essential and functional amino acids, with glutamic and aspartic acids as dominant components. The hydrolysate exhibited notable antioxidant activity, achieving 55.17% DPPH radical scavenging at 1 mg/mL. No significant reducing capacity was observed in the CUPRAC assay, suggesting that antioxidant activity is mainly associated with radical scavenging rather than metal ion reduction. No antimicrobial activity was detected against Staphylococcus aureus or Escherichia coli, consistent with the association of antimicrobial defense in mollusks with hemolymph-derived components rather than muscle tissue. Elemental analysis indicated the absence of chromium and cadmium, while lead and mercury were present at low levels. Nutritionally relevant minerals, including magnesium, iron, zinc, and copper, were retained in the protein-rich fraction. These findings demonstrate that enzymatic hydrolysis of R. venosa muscle yields a structurally and functionally favorable protein ingredient with a controlled elemental profile.