Tang Ning, Zhuang Hong
Authors are with Dept. of Food Science and Engineering, Jilin Univ, Changchun, China.
J Food Sci. 2014 Nov;79(11):C2174-84. doi: 10.1111/1750-3841.12686. Epub 2014 Oct 28.
Zein protein was extracted from the by-product corn gluten meal. The obtained zein protein was 1st hydrolyzed by 4 different proteases. The antioxidant activities of the hydrolysates or peptides were evaluated by free radical scavenging activity, metal ion chelating activity, and lipid peroxidation inhibitory capacity. Among hydrolysates produced, alkaline protease hydrolysates exhibited the highest antioxidant activity. A regression model was established by uniform design to optimize the alkaline protease hydrolysis conditions. The hydrolysates with molecular weight < 3 kDa obtained from ultrafiltration showed the highest antioxidant activities in all relevant assays. The hydrolysates with molecular weight <3 kDa were subsequently purified by gel filtration chromatography, and fraction F3 exhibited the highest antioxidant activities. Two peptides were identified from fraction F3 using LC-ESI-Q-TOF MS/MS as Pro-Phe (263.13 Da) and Leu-Pro-Phe (375.46 Da). These peptides exhibited good free radical scavenging activity and lipid peroxidation inhibitory effect. The results clearly indicated that zein protein fractions are good sources for the development of natural antioxidants for the food industry.
玉米醇溶蛋白是从副产品玉米蛋白粉中提取的。将得到的玉米醇溶蛋白首先用4种不同的蛋白酶进行水解。通过自由基清除活性、金属离子螯合活性和脂质过氧化抑制能力来评估水解产物或肽的抗氧化活性。在所产生的水解产物中，碱性蛋白酶水解产物表现出最高的抗氧化活性。通过均匀设计建立回归模型以优化碱性蛋白酶的水解条件。通过超滤获得的分子量<3 kDa的水解产物在所有相关测定中表现出最高的抗氧化活性。随后通过凝胶过滤色谱法对分子量<3 kDa的水解产物进行纯化，F3组分表现出最高的抗氧化活性。使用LC-ESI-Q-TOF MS/MS从F3组分中鉴定出两种肽，分别为Pro-Phe（263.13 Da）和Leu-Pro-Phe（375.46 Da）。这些肽表现出良好的自由基清除活性和脂质过氧化抑制作用。结果清楚地表明，玉米醇溶蛋白组分是食品工业开发天然抗氧化剂的良好来源。
