菠萝蛋白酶水解泥鳅蛋白制备ACE抑制肽的研究

为了探讨利用泥鳅蛋白制备功能性肽的可能性，采用高效液相色谱法测定泥鳅肉水解物对血管紧张素转换酶(ACE)的抑制作用，从胰蛋白酶、胃蛋白酶、菠萝蛋白酶、复合风味蛋白酶、复合蛋白酶5种酶中筛选出菠萝蛋白酶作为酶解泥鳅肉制备具有降血压活性水解物的适宜水解酶。在单因素试验的基础上，采用L9(34)正交试验设计对该酶的酶解条件进行优化。结果表明最佳水解条件为：温度55℃，固液比1:3，pH6.5，加酶量1000U/g pro，水解时间90min。在该条件下，水解物的ACE抑制率IC50值为0.0184mg/mL，ACE抑制肽的相对分子质量主要集中在924左右。

Preparation of ACE Inhibitory Peptides by Bromelain Hydrolysis of Loach(Misgurnus anguillicaudatus) Protein

The present deals with the enzymatic preparation of angiotensin-converting enzyme(ACE) inhibitory active peptides from loach(Misgurnus anguillicaudatus) protein.An L9(34) orthogonal array design methods based on single factor experiments was used to optimize the hydrolysis conditions for achieving maximum ACE inhibitory activity of loach protein hydrolysates.HPLC was used to determine ACE inhibitory activity of loach protein hydrolysates.Bromelain was found to be more suitable to prepare ACE inhibitory active peptides than trypsin,pepsin,flavourzyme and protamex.The optimal hydrolysis conditions were temperature of 55 ℃,solid-to-liquid ratio of 1:3,pH of 6.5,bromelain dose of 1000 U/g protein and hydrolysis duration of 90 min.The IC50 of the loach protein hydrolysate obtained under these conditions was 0.0184 mg/mL and the relative molecular weight distribution of ACE inhibitory peptides in it was mainly concentrated around 924.