史氏鲟鱼皮肽的提取、鉴定及其血管紧张素转化酶抑制活性

Extraction,Isolation and ACE inhibition of Peptides from Sturgeon(Acipenser schrenckii)Skin

【目的】确定史氏鲟(Acipenser schrenckii)鱼皮肽最佳酶解条件,了解其血管紧张素转换酶(ACE)抑制活性,探究史氏鲟鱼皮在ACE抑制活性肽段的开发应用的可行性。【方法】参照国标方法测定鲟鱼皮基本组成成分;以水解度和ACE抑制率为指标,采用单因素实验对最适水解酶、加酶量、料液比、温度以及时间确定鲟鱼鱼皮肽最佳酶解条件;使用不同截留相对分子质量的超滤膜设备分离纯化鲟鱼皮肽,并比较其ACE抑制率;随后对最优肽组分进行紫外光谱、分子质量范围、肽序列测定和生物学活性预测。【结果与结论】鲟鱼皮干基主要由蛋白质和脂肪组成。确定鲟鱼皮肽最佳酶解条件为使用碱性蛋白酶、酶添加量6000 U/g,料液质量体积比1 g∶5 mL,温度60℃,酶解时间7 h。分离纯化后得到3种相对分子质量不同的鲟鱼皮肽,分别为ASPs-1、ASPs-2和ASPs-3,其中最优肽组分ASPs-1的分子质量范围为172.13~2135.02u,共鉴定获得28条综合得分大于100的肽段,分子质量集中在807.45~1952.96 u;其中GPGGPSGERGPPGPM、GPSGPGGPPGPR、SGPPGFPGSPGPKGE、GPPGKDGQPGHPGPIGPA、GPAGPRGPAGPA五条肽段预测具有ACE抑制功能,水溶性好,无生物学毒性,说明ASPs-1作为ACE抑制剂,有运用于生物体的潜力。

【Objective】To determine the optimal enzymatic hydrolysis conditions and ACE inhibition for Acipenser schrenckii skin peptides(ASPs)and explore the feasibility of their application in the targeted development of angiotensin-converting enzyme(ACE)inhibitory active peptides【Method】The basic components of sturgeon skin were determined according to the national standard method.With the degree of hydrolysis and ACE inhibition as indices,the optimal enzymatic hydrolysis conditions of sturgeon skin peptide were determined by single factor experiment for the optimal hydrolase enzyme,enzyme dosage,solid-liquid ratio,temperature and time.Ultrafiltration membrane equipment with different relative molecular weight cut-offs was used to separate sturgeon skin peptides,and their ACE inhibition rates were compared.Subsequently,the optimal peptide components were studied by ultraviolet spectroscopy,relative molecular weight range determination,peptide sequence determination,and biological activity prediction.【Results and Conclusion】The dry base of sturgeon skin was mainly composed of protein and fat.The optimal enzymatic hydrolysis conditions of sturgeon skin peptide were alkaline protease,enzyme addition 6000 U/g,solid-liquid ratio 1∶5(g/mL),60°C,and 7 h.The relative molecular weight range of ASPs-1,the optimal peptide component,was 172.13-2135.02 u,and a total of 28 peptides with a comprehensive score greater than 100 were identified,with a relative molecular weight of 807.45-1952.96 u.Among them,GPGGPSGERGPPGPM,GPSGPGGPPGPR,SGPPGFPGSPGPKGE,GPPGKDGQPGHPGPIGPA,GPAGPA were predicted to have ACE inhibition function,and had good water solubility and no biological toxicity.Therefore,it is speculated that ASPs-1 has the potential to be used as an ACE inhibitor in living organisms.