ABSTRACT

Sesame seed was defatted and subsequently fractionated into albumin, globulin, glutelin and prolamin. The defatted flour was also subjected to alkaline solubilization and acid precipitation to obtain protein isolate. The sesame seed protein isolate was hydrolyzed using a combination of pepsin and pancreatin to produce the protein hydrolyzate. The defatted flour, protein fractions, isolate and hydrolyzate were evaluated for their amino acid profiles as well as in vitro antioxidant and enzyme inhibitory activities. The results showed that the glutelin fraction had higher amounts of essential amino acid (38.1%) when compared with albumin (35.6%), globulin (31.3%), prolamin (37.1%), protein isolate (37.1%) and protein hydrolyzate (36.7%). The defatted flour exhibited the strongest DPPH radical scavenging activity while only the globulin, isolate and hydrolyzate exhibited superoxide radical scavenging activity. The defatted flour also had the strongest hydroxyl radical scavenging activity of 91.79%, although lower than the 95.93% for the control peptide (glutathione). The hydrolyzate had the strongest metal chelating activity (75.53%), while the isolate had the highest ferric antioxidant reducing power. The albumin was the most effective inhibitor of angiotensin converting enzyme and α-amylase with values of 30.04% and 29.44%, respectively. In contrast, renin activity was strongly inhibited (89.87%) by the isolate but acetylcholinesterase was weakly inhibited by the hydrolyzate (16.89%) and prolamin (16.29%). We conclude that the defatted flour and protein products are potential ingredients that could be incorporated into foods to extend shelf-life but also with potential bioactive properties.

摘要

将芝麻种子脱脂，然后分级分离为白蛋白，球蛋白，谷蛋白和谷醇溶蛋白。还将脱脂的面粉进行碱溶解和酸沉淀以获得蛋白质分离物。使用胃蛋白酶和胰酶的组合将芝麻籽蛋白分离物水解以产生蛋白水解物。对脱脂面粉，蛋白质级分，分离物和水解产物的氨基酸谱以及体外抗氧化剂和酶抑制活性进行了评估。结果表明，与白蛋白（35.6％），球蛋白（31.3％），谷醇溶蛋白（37.1％），分离蛋白（37.1％）和蛋白水解物（36.7）相比，谷蛋白部分具有更高的必需氨基酸含量（38.1％）。 ％）。脱脂面粉显示出最强的DPPH自由基清除活性，而只有球蛋白，分离物和水解物显示出超氧自由基清除活性。脱脂面粉还具有最强的清除羟自由基的活性，为91.79％，尽管低于对照肽（谷胱甘肽）的95.93％。水解产物具有最强的金属螯合活性（75.53％），而分离物具有最高的三价铁抗氧化剂还原能力。白蛋白是血管紧张素转化酶和α-淀粉酶的最有效抑制剂，其值分别为30.04％和29.44％。相反，分离物强烈抑制肾素活性（89.87％），而水解产物（16.89％）和醇溶蛋白（16.29％）则弱抑制乙酰胆碱酯酶。