利用Alcalase 2.4L酶解鱼鳞明胶制备具有血管紧张素转化酶（ACE）抑制活性的降血压肽，通过超滤处理富集得到具有较高活性的ACE抑制肽，并对该组分进行分子量分布、氨基酸组成分析及抗消化性研究。结果表明：水解明胶6 h所得水解物的ACE抑制活性最高，其IC50为0.56 mg/mL，水解度为15.54%；超滤膜处理分离后，分子量小于5 kDa的多肽组分Ⅱ的ACE抑制活性最高，其回收率达90%以上；多肽中对ACE抑制活性贡献大的脯氨酸、羟脯氨酸、色氨酸等疏水性氨基酸的保存率高；体外消化实验显示，该抑制肽在胃肠道消化酶作用下能保持较好的ACE抑制活性。

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.

新世纪优秀人才支持计划资助（NCET-10-0362），中央高校基本科研业务费专项资金资助（2012ZG0007）