植物乳杆菌和蛋白酶协同发酵水解大米蛋白ACE抑制肽高活性组分的氨基酸序列分析

利用低大米蛋白制备过程发酵水解液中富含大米蛋白和肽。以乳杆菌L2-18+风味蛋白酶/菠萝蛋白酶+胃蛋白酶/酸性蛋白酶分步获得的大米蛋白水解液为研究对象,通过超滤获得小于3 kDa蛋白肽。经阳离子交换、凝胶柱层析和高效液相色谱(high performance liquid chromatography,HPLC)三步分离纯化,确定出高活性ACE抑制肽组分,IC_(50)值为33.81μg/mL。经液质联用(liquid chromatograph-mass spectrometer,LC-MS)鉴定分析,其多肽序列为VVFFAAAL。     

大米蛋白肽的制备与ACE抑制活性分析

通过优化大米蛋白的单酶酶解与双酶酶解工艺,确定了采用碱性蛋白酶加蛋白酶B复合酶解制备大米蛋白肽的工艺.蛋白回收率高达43.9％,制备的大米蛋白肽感官评价高、苦味低、分子质量小.对比市售的大豆蛋白肽、鱼胶原蛋白肽,3种蛋白肽的水分含量、蛋白质含量、脂肪含量基本接近.大米蛋白肽与大豆蛋白肽中分子质量<2000 Da的总比例...     

逆流超声辅助酶解法制备大米ACE抑制肽

研究逆流超声预处理大米蛋白对其碱性蛋白酶酶解制备血管紧张素转换酶(Angiotensin-I Converting Enzyme,ACE)抑制肽的影响。首先从米渣中提取大米蛋白,以ACE抑制率为主要指标,水解度为辅助指标,运用单因素逐级优化法对酶解反应的底物浓度、时间、温度、加酶量和pH进行参数优化,在此基础上筛选逆流超声模式的最佳超声参数。结果表明最佳酶解参数为底物浓度30 g/L、加酶量(E/S)7.5%、温度50 ℃、pH8.5和酶解时间60 min,此时酶解产物ACE抑制率为45.59%,水解度为21.49%。最佳超声参数为超声频率20 kHz、功率密度170 W/L、时间12.5 min。此时酶解液ACE抑制率达72.24%,水解度为21.64%,相较于未超声组ACE抑制率提高了57.42%,相较于传统超声组,ACE抑制率提高了11.36%。结果表明逆流超声波辅助酶解法能有效提高酶解效率、减少能耗、促进ACE抑制肽制备。     

酶解丝素蛋白制备ACE抑制肽的研究

本研究首次探讨利用Alcalase酶解丝素蛋白制备高活性ACE抑制肽.以水解度为主要评价指标,研究了温度、浓度、pH、加酶量以及反应时间对酶解反应的影响.分析了不同水解度下的酶解产物与ACE体外抑制活性、肽得率和蛋白回收率的关系.确定了制备ACE抑制肽的最佳酶解反应DH值为17.12％,此时所得丝素蛋白肽的肽得率为50...     

大米免疫活性肽水解用酶的筛选

研究Neutrase、Acalase 2.4 L、Papain、Pepsin、Trypsin、Flavourzyme、Acid protease、Protamex与Bromelain 9种蛋白酶水解大米蛋白的进程特性,考察9种蛋白酶水解物的免疫活性。结果表明,胰脏蛋白酶Trypsin可作为制备大米免疫活性肽的最适水解酶,Trypsin酶解物对小鼠巨噬细胞(RAW264.7)的增值指数(stimulating index,SI)为1.597(1 000μg/m L);其酶解物中相对分子质量1 000的组分比例最高,达到74.11%。     

酶水解米渣蛋白制备大米肽研究

该研究利用米渣蛋白制备大米肽的适宜酶水解条件,结果表明:在pH 8．5、温度55℃、酶用量2．0％条件下水解3h,水解液中5％TCA可溶性肽含量可达37％以上。     

花生蛋白水解产物ACE抑制活性的研究

采用胰蛋白酶、碱性蛋白酶、中性蛋白酶水解花生蛋白,研究了水解过程中水解度的变化,并对水解产物的ACE抑制活性进行了探讨。得出三种酶对花生蛋白的水解作用:碱性蛋白酶>胰蛋白酶>中性蛋白酶。碱性蛋白酶水解产物ACE抑制活性明显高于胰蛋白酶和中性蛋白酶,水解产物的ACE抑制活性高达89.73%,中性蛋白酶水解产物ACE抑制率仅为27.24%。     

贻贝中ACE抑制活性肽的酶解制备及表征

以贻贝为原料,制备具有血管紧张素Ⅰ转换酶(ACE)抑制作用的活性肽.采用水解度DH、蛋白质回收率及ACE抑制活性为指标,筛选水解贻贝粗蛋白的最适酶种;通过响应面分析(RSM)对水解贻贝粗蛋白的工艺条件进行优化;探讨水解度(DH)与ACE抑制活性的关系;利用HPLC方法分析活性肤的相对分子质量分布.试验结果表明碱性蛋白酶Alcalase 2.4 L是水解贻贝粗蛋白的最适酶种;碱性蛋白酶在[E]/[S]1.64、pH 9.12、温度57 ℃水解条件下,酶解物的ACE抑制作用最强,其DH26.41%,IC50 34.64g/mL.就贻贝粗蛋白的水解而言,控制水解度为25%～30%为宜.碱性蛋白酶水解贻贝粗蛋白所得活性肤,主要是以相对分子质量较小的短肽组成,其中,相对分子质量在1 000 Da以内的占90.42%.本研究结果表明以贻贝为原料,可以开发具有显著ACE抑制活性的降血压肤.     

酶解燕麦蛋白制备ACE抑制肽的研究

本研究以燕麦蛋白为原料,分别选用Alcalase、Neutrase 和Protamex 进行单独或联合水解,经活性炭YD-303脱色、大孔吸附树脂DA-201C Ⅱ脱盐及分级纯化、Sephadex G-25 凝胶色谱柱进一步分离,以获得高纯度、高活性的血管紧张素转化酶(angiotensin converting enzyme,ACE)抑制肽。结果表明：单酶反应时,Alcalase 水解2h所获得的产物对ACE 的抑制率可达85.40%;YD-303 处理燕麦蛋白酶解液脱色最优工艺为添加量1.5%(W/V)、pH3.5、温度40℃、脱色时间75min。利用75% 乙醇洗脱大孔吸附树脂DA-201C Ⅱ所获得的组分ACE 抑制活性最高,其经Sephadex G-25 进一步分离纯化,得到四个分离组分,第四组分的ACE 抑制活性最高,抑制率为95.6%。     

酶法制备燕麦麸蛋白ACE抑制肽的研究

采用碱溶酸沉法制备了燕麦麸蛋白,并利用7种商业化蛋白酶对其进行酶解以考察生产ACE抑制肽的效果,结果表明Alcalase为最适用酶。优化了Alcalase水解燕麦麸蛋白的工艺条件,在[S]=5.0%,E/S=1.33%,pH7.5,温度60℃条件下酶解90min,酶解产物的ACE抑制活性最强(IC50=0.291mg/mL),此时水解度为11.0%,产物的相对分子质量主要集中在880Da以下。     

三斑海马蛋白ACE抑制肽的制备及其二级结构的研究

以三斑海马为原料,经碱性蛋白酶酶解,获得富含血管紧张素转化酶(angiotensin I-converting enzyme,ACE)抑制肽的酶解液。酶解液经透析、Sephadex G-25凝胶过滤色谱和反相高效液相色谱得到进一步分离纯化。结果表明,透析产物的IC50值为(0.44±0.26)mg/mL,相比酶解液(0.81±0.12)mg/mL,其ACE抑制活性更强。透析产物经Sephadex G-25凝胶柱分离纯化后,得到3种组分,其中组分F2的ACE抑制活性最强,IC50值为(0.11±0.08)mg/mL。F2经反相高效液相色谱进一步分离后,得到6个具有ACE抑制活性的组分峰,其中组分F2-4的ACE抑制活性最强,IC50值为(0.005 7±0.000 9)mg/mL。经过3步分离纯化后,成功从三斑海马蛋白中分离得到一种活性较强ACE抑制肽:ProAla-Gly-Pro-Arg-Gly-Pro-Ala(PAGPRGPA),多肽分子量为721.39 Da。圆二色谱分析多肽二级结构表明其主要含无规则卷曲。因此,从三斑海马蛋白中分离得到的多肽可能成为营养保健品和抗高血压药品及相关疾病的一种有益成分,且对海马蛋白资源的开发利用具有重要意义。     

小龙虾头中血管紧张素转化酶抑制肽提取工艺优化研究

采用胃蛋白酶水解小龙虾头制备血管紧张素转化酶(ACE)抑制肽,通过体外检测法测定ACE抑制率。采用二次旋转优化组合试验对制备工艺进行优化,结果表明:pH2.4,温度40.85℃,底物浓度10.05%,酶-底物质量比6.97,水解4.5 h时ACE抑制率可达到80.9%。     

我国豆酱血管紧张素转换酶抑制活性的比较

文章对我国三种市售豆酱的血管紧张素转换酶(ACE)抑制活性及其主要化学组成进行比较分析,所试样品的IC50值分别为1.373、0.876和1.691 mg/mL,活性最高样品中的多肽含量为24.09g/100g dry matter,不同样品间多肽分布无明显差异。样品的ACE抑制活性应为多种活性物质综合作用的结果,对其中ACE抑制剂构效关系的研究可为我国豆酱功能性的研发提供指导。     

Effects of Lycii fructus and Edible Mushroom, Pholiota adiposa, on the Quality and Angiotensin I-Converting Enzyme Inhibitory Activity of Korean Traditional Rice Wine

The goal of this study was to develop a high value Korean traditional rice wine possessing the antihypertensive functionality. The effects of the Lycii fructus and Pholiota adiposa on the alcohol fermentation and its angiotensin I-converting (ACE) inhibitory activity of Korean traditional rice wine, yakju were investigated. Optimal fermentation conditions for the preparation of yakju consisted of the koji added at 10% and a fermentation period of 10 days at 25˚C. The best acceptability appeared with the Lf-1 traditional rice wine that was brewed by the addition of 1% Lycii fructus into the mash containing cooked rice, koji and antihypertensive S. cerevisiae. Its antihypertensive ACE inhibitory activity was 76%. Its ACE inhibitory activity was also increased about 8% by the addition of 0.1% of the edible mushroom Pholiota adiposa ASI 24012 fruiting bodies into the mash, showing good sensory characteristics. From these results, Lf-Pa1 yakju which was brewed by addition of 1% Lycii fructus and 0.1% Pholiota adiposa into the mash, has the potential to become a new functional Korean traditional rice wine with high antihypertensive properties.     

Effects of Lycii fructus and Edible Mushroom,Pholiota adiposa,on the Quality and Angiotensin I-Converting Enzyme Inhibitory Activity of Korean Traditional Rice Wine

The goal of this study was to develop a high value Korean traditional rice wine possessing the antihypertensive functionality. The effects of the Lycii fructus and Pholiota adiposa on the alcohol fermentation and its angiotensin I-converting (ACE) inhibitory activity of Korean traditional rice wine, yakju were investigated. Optimal fermentation conditions for the preparation of yakju consisted of the koji added at 10% and a fermentation period of 10 days at 25?C. The best acceptability appeared with the Lf-1 traditional rice wine that was brewed by the addition of 1% Lycii fructus into the mash containing cooked rice, koji and antihypertensive S. cerevisiae. Its antihypertensive ACE inhibitory activity was 76%. Its ACE inhibitory activity was also increased about 8% by the addition of 0.1% of the edible mushroom Pholiota adiposa ASI 24012 fruiting bodies into the mash, showing good sensory characteristics. From these results, Lf-Pa1 yakju which was brewed by addition of 1% Lycii fructus and 0.1% Pholiota adiposa into the mash, has the potential to become a new functional Korean traditional rice wine with high antihypertensive properties.     

Selected Quality Properties and Angiotensin I-Converting Enzyme Inhibitory Activity of Low-Salt Sufu,A New Type of Chinese Fermented Tofu

Low salt diets have become a trend due to the increase in health awareness. This study was carried out to investigate the quality and angiotensin I-converting enzyme inhibitory activity of low-salt sufu. Results showed that fermentation and the ripening process led to the release of peptides, greatly improving angiotensin I-converting enzyme inhibitory activity of low-salt sufu. Angiotensin I-converting enzyme inhibitory activity of low-salt sufu had thermostability, and its activity increased with a decrease in pH value. After in vitro protease digestion, angiotensin I-converting enzyme inhibitory activity increased significantly. When treated with protease alone, the sample digested with pepsin had the highest angiotensin I-converting enzyme inhibitory activity. Furthermore, the samples digested by gastrointestinal proteases in combination showed an even higher angiotensin I-converting enzyme inhibitory activity. Specifically, the sample digested by pepsin + α-chymotrypsin exhibited the lowest IC50 value of 0.015 mg/ml. These results suggested that low-salt sufu had a great potential to serve as a functional food in hypertension prevention.     

Angiotensin I-Converting Enzyme Inhibitory Activity of Soy Protein Digests in a Dynamic Model System Simulating the Upper Gastrointestinal Tract

ABSTRACT: The objective of this study was to investigate whether peptides with inhibitory activity against angiotensin I-converting enzyme (ACE) would be produced by digestion of isolated soy protein (ISP) in a dynamic model system simulating gastrointestinal conditions. Using the model system, 5% ISP solution was pumped into the stomach reactor containing pepsin and HCl. The peptic digest was continuously pumped into the duodenum reactor containing pancreatin and Oxgall bile. The effects of blanching (100°C, 10 min) followed by pasteurization (75°C, 15 s) or sterilization (121°C, 20 min) of ISP before digestion on the inhibitory activity were also investigated. During the first 30 min of digestion, significantly higher ( P < 0.05) ACE-inhibitory activity was generated from unheated ISP after sequential digestion in both reactors compared with after peptic digestion only in the stomach reactor. However, at 90 min, subsequent digestion by pancreatin of unheated and blanched-sterilized ISP decreased ACE-inhibitory activity compared with peptic digestion alone. The IC₅₀ values at the end of 90 min digestion in both reactors were 0.38 ±0.01, 0.37 ± 0.02, and 0.44 ± 0.02 mg/mL for unheated, blanched-pasteurized, and blanched-sterilized ISP, respectively. The results suggest the potential production of peptides with ACE-inhibitory activity upon physiological digestion of soy protein, including products that have been subjected to heat processing. Although clinical trials would be required to provide final evidence of efficacy of the soy peptides, the present findings support the application of soy protein as an ingredient for functional foods.     

微生物发酵法制备大豆ACE抑制肽菌种的筛选

以大豆分离蛋白为底物,以血管紧张素转化酶(ACE)抑制率和肽含量为检测指标,选择5株乳酸菌、3株霉菌和1株枯草芽孢杆菌为出发菌种,通过微生物发酵筛选出具有高ACE抑制活性的发酵菌株。结果表明:乳酸菌中具有强ACE抑制活性的菌株为保加利亚乳杆菌,ACE抑制率和肽含量分别为57.93%和3.27mg/mL;霉菌中具有强ACE抑制活性的菌株为米曲霉,ACE抑制率和肽含量分别为41.23%和2.17mg/mL;枯草芽孢杆菌ACE抑制率和肽含量分别为45.02%和2.25mg/mL。综合比较9种菌株的发酵特性,选用保加利亚乳杆菌作为制备大豆抗高血压活性肽优良菌株。