酱油发酵用2种米曲霉中性蛋白酶的酶学性质比较  

Characteristic Comparison of Two Neutral Proteases Used for Soy Sauce Fermentation

作　　者：王栋[1,2] 冯杰[1,2] 郑志永[1,2] 张丽敏[1,2] 詹晓北[1,2] 

机构地区：[1]江南大学生物工程学院 [2]江南大学工业生物技术教育部重点实验室,江苏无锡214122

出　　处：《食品与生物技术学报》2012年第5期479-485,共7页Journal of Food Science and Biotechnology

基　　金：国家"十一五"科技支撑计划项目(2008BAI63B06;2007BAK36B03);国家"十二五"科技支撑计划项目(2011BAD23B04)

摘　　要：米曲霉产蛋白酶的性质对酱油品质有重要的影响。研究以一株产中性蛋白酶的米曲霉CICIM F0899为研究对象,首先对其进行扫描电镜观察,与米曲霉沪酿3.042比较表明F0899的分生孢子头较小,分生孢子大于沪酿3.042。其次对F0899和沪酿3.042产蛋白酶酶学性质研究表明F0899产蛋白酶在20～40℃保持稳定,最适反应温度为60℃,在pH 6.0～8.0时保持稳定,最适反应pH为8.0,在盐浓度为18%的条件下,仍能保留20%的酶活,可达沪酿3.042的2.2倍,Ag+对F0899有严重的抑制作用,Fe3+没有明显的抑制。因此,米曲霉CICIM F0899产的蛋白酶在耐高温、耐低pH和耐高盐的性能优于沪酿3.042。The characterization of protease from Aspergillus oryzae has a significant impact on soy sauce quality.In this study,an Aspergillus oryzae CICIM F0899 capable of producing neutral protease was investigated.Morphology of Aspergillus oryzae F0899 and Aspergillus oryzae 3.042 were imaged by SEM.The conidial head of Aspergillus oryzae F0899 was relatively smaller than that of the strain 3.042.Its conidia were larger than that of the 3.042 strain.In addition,properties of the protease secreted by this strain were tested and compared with profiles of an industrially strain Aspergillus oryzae 3.042.The results showed that the optimum temperature for the extracellular protease from F0899 was 60℃,with the stable temperature range between 20~40℃.The optimal pH was 8.0,with the stable pH range between 6.0~8.0.It could tolerate 18% sodium chloride and still retains 20% activity,which is as high as 2.2 times than that from 3.042 under the same condition.The activity of the enzyme was severely inhibited by Ag+,but affected by Fe3+ only slightly.Therefore,protease from Aspergillus oryzae F0899 can bear higher temperature,lower pH and higher NaCl concentration than that from 3.042.

关 键 词：酱油发酵 大曲 蛋白酶 酶学性质 米曲霉 

分 类 号：TS264.21[轻工技术与工程—发酵工程]