泥鳅ACE抑制肽的体外活性研究

以泥鳅蛋白为原料,酶解制备具有降血压活性的短肽,研究该肽的稳定性。在加热温度≤80℃条件下加热2h,泥鳅降血压肽(<2.5ku)的ACE抑制活性没有显著变化。当2.0≤pH≤8.0时,泥鳅降血压肽的ACE抑制活性变化不显著。冷冻干燥优于喷雾干燥。Mg2+对泥鳅降压肽的降压活性起到促进作用,而Zn2+和Mn2+抑制了肽的降压活性。葡萄糖对降压肽活性的影响程度明显大于蔗糖,随着浓度的升高,其ACE抑制活性逐渐降低,褐变程度加深;氯化钠对降压活性的影响不明显。在模拟胃肠道消化体系中,胃蛋白酶的消化显著提高了产物的降压活性;胰酶的消化降低了产物的降压活性。泥鳅多肽属于底物型ACE抑制肽。

Activity of angiotensin-Ⅰ-converting enzyme inhibitory peptide from loach(Misgurnus anguillicaudatus)proteins in vitro

The aim of this study was to investigate the stability of angiotensin-I-converting enzyme inhibitory peptide from loach.The ACE inhibitory activity of loach peptide(<2.5ku) didn’t decrease after 2h heating below 80℃and remained at high active stability from pH2.0 to 8.0.Based on evaluation of ACE inhibitory activity,freeze drying was better than spray drying.Mg2+ promoted the angiotensin-I-converting enzyme inhibitory activity,while the Zn2+ and Mn2+ inhibited the angiotensin-I-converting enzyme inhibitory activity.Effect of glucose on the angiotensin-I-converting enzyme inhibitory activity significantly was greater than sucrose.With the increase of glucose concentration,the ACE inhibition activity gradually decreased and browned greater.Sodium chloride had no significant effect on antihypertensive activity.Peptides exhibited higher angiotensin-I-converting enzyme inhibitory activity hydrolysis by pepsin,but lower angiotensin-I-converting enzyme inhibitory activity after further hydrolysis by trypsin.Loach peptide belonged to the substrate type of ACE inhibitor.