Abstract:Fish scalses gelatin was hydrolyzed by Alcalase 2.4L protease and concentrated by ultrafiltration to gather the bioactive peptides. The inhibitory activity, molecular weight distribution, amino acid composition and the resistance of digestive proteases were determined. The results showed that the hydrolysate has the highest ACE-inhibitory activity with an IC50 of 0.56 mg/mL and a DH of 15.54% after a 6-hour- hydrolysis. Component Ⅱ (peptides <5 kDa) obtained after ultrafiltration showed the strongest inhibitory activity and a high recovery rate above 90%. The hydrophobic amino acids of alanine, tryptophan and proline which contribute the most for ACE-inhibitory activity were well reserved in component Ⅱ. Artificial gastrointestinal digestion test indicated that the bioactive peptides in fish scale were resistant to digestive proteases.
