Li Li, Yang Zuo-Yi, Yang Xiao-Qun, Zhang Gui-He, Tang Shu-Ze, Chen Feng
Research and Development Center of Food Proteins, College of Light Industry and Food Science, South China University of Technology, Guangzhou, 510641, China.
J Ind Microbiol Biotechnol. 2008 Jan;35(1):41-7. doi: 10.1007/s10295-007-0264-y. Epub 2007 Oct 18.
Effects of the enzymes in Actinomucor elegans extract and the enzyme Alcalase 2.4L on debittering the soybean protein hydrolysates were investigated. When the protein was treated only with the latter, a strong bitterness formed; but it decreased if the protein was treated with both the enzymes. The more the enzymes were used, weaker was the bitterness tasted. SDS-PAGE profile and ESI-MS spectrum of the hydrolysates evidenced that the Alcalase could convert the protein into peptides rapidly, while the enzymes in the A. elegans extract were able to further degrade some peptides which were difficult or unable to be hydrolyzed by the Alcalase. Further systematic analysis of the peptidases showed that the Alcalase exhibited a significant endopeptidase activity towards NBZ-Phe-pNA substrate (p < 0.01), whereas many exopeptidases in the A. elegans extract had the carboxypeptidase activity towards N-CBZ-Ile-Leu (p < 0.01). It is concluded that those exopeptidases presented in the A. elegans extract can benefit by decreasing the bitterness of the soybean protein hydroysate. They are also capable of being used with the Alcalase in a single-step enzymatic reaction to prepare the bitterless protein hydrolysate, which may be an efficient application for food industry.
研究了雅致放射毛霉提取物中的酶和碱性蛋白酶Alcalase 2.4L对大豆蛋白水解物脱苦的影响。当仅用后者处理蛋白质时，会形成强烈的苦味；但如果用两种酶处理蛋白质，苦味会降低。使用的酶越多，尝起来的苦味越淡。水解物的SDS-PAGE图谱和ESI-MS光谱表明，碱性蛋白酶可以迅速将蛋白质转化为肽，而雅致放射毛霉提取物中的酶能够进一步降解一些难以或无法被碱性蛋白酶水解的肽。对肽酶的进一步系统分析表明，碱性蛋白酶对NBZ-Phe-pNA底物表现出显著的内肽酶活性（p < 0.01），而雅致放射毛霉提取物中的许多外肽酶对N-CBZ-Ile-Leu具有羧肽酶活性（p < 0.01）。得出的结论是，雅致放射毛霉提取物中存在的那些外肽酶可以通过降低大豆蛋白水解物的苦味而发挥作用。它们还能够与碱性蛋白酶在一步酶促反应中一起使用，以制备无苦味的蛋白水解物，这可能是食品工业中的一种有效应用。
