Zhongguo youzhi (Dec 2022)
微胚乳玉米醇溶蛋白的提取及氨基酸组成分析Extraction and amino acid composition analysis of zein from micro-endosperm maize
Abstract
为促进微胚乳玉米醇溶蛋白的开发和应用,以微胚乳玉米为原料,分别采用乙醇浸提法和超声波辅助乙醇浸提法提取玉米醇溶蛋白,通过单因素实验优化工艺条件,并对微胚乳玉米醇溶蛋白的氨基酸组成进行分析。结果表明:乙醇浸提法提取微胚乳玉米醇溶蛋白的最优工艺条件为提取温度50 ℃,提取时间 2.0 h,乙醇体积分数80%,料液比1∶ 12;超声波辅助乙醇浸提法提取微胚乳玉米醇溶蛋白的最优工艺条件为乙醇体积分数80%,超声时间40 min,料液比1∶ 20,超声功率500 W。在各自最优条件下,超声波辅助乙醇浸提法所得微胚乳玉米醇溶蛋白提取率和蛋白质含量分别为4588%和82.1%,显著优于乙醇浸提法的32.61%和79.2%。微胚乳玉米醇溶蛋白的非极性氨基酸占比为59.11%,高于普通玉米醇溶蛋白的53.38%。综上,与乙醇浸提法相比,超声波辅助乙醇浸提法具有较强的优越性;微胚乳玉米醇溶蛋白较普通玉米醇溶蛋白显示出更强的疏水性。 To promote the development and application of zein from micro-endosperm maize, zein was extracted from micro-endosperm maize by ethanol extraction method and ultrasonic assisted ethanol extraction method. The process conditions were optimized by single factor experiments, and the amino acid composition of zein from micro-endosperm maize was analyzed. The results showed that the optimal conditions for ethanol extraction method were obtained as follows: extraction temperature 50 ℃, extraction time 2.0 h, ethanol volume fraction 80% and solid-liquid ratio 1∶ 12. The optimal conditions for ultrasonic assisted ethanol extraction method were obtained as follows: ethanol volume fraction 80%, ultrasonic time 40 min, solid-liquid ratio 1∶ 20 and ultrasonic power 500 W. Under these optimal conditions, the extraction rate and protein content of zein from micro-endosperm maize extracted by ultrasonic assisted ethanol extraction method were 45.88% and 82.1%, respectively, which were significantly better than 32.61% and 79.2% extracted by ethanol extraction method. The non-polar amino acid proportion of zein from micro-endosperm maize was 59.11%, which was higher than 53.38% of common zein. In conclusion, compared with ethanol extraction method, ultrasonic assisted ethanol extraction method has stronger advantages, and zein from micro-endosperm maize shows stronger hydrophobicity than common zein.
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