摘要
交联酶聚集体法(cross-linked enzyme aggregates,CLEAs)是一种新型的无载体酶固定化方法。使用该法固定化黑曲霉产单宁酶,制备无载体固定化单宁酶(Cross-linkedenzyme aggregates-tannase,CLEAs-TA),并对其制备条件、结构特征、酶学性质进行分析。结果表明,最优制备条件为单宁酶游离粗酶液在冰水浴中经80%的硫酸铵沉淀30min后,以1.5%戊二醛水溶液进行酶聚集体交联反应,可获得较高活性、较高稳定性的交联酶聚集体,酶活回收率达47.33%,对酯键水解作用的最适温度、最适pH值分别为50℃、4.5,与游离酶相比,表现更高的pH及温度稳定性,重复使用6次后,活力剩余32.86%,其良好的操作稳定性有利于没食子酸丙酯高效转化为没食子酸及广泛应用于水解茶饮料中单宁的反应。
Cross-linked enzyme aggregates（CLEAs）were first used to immobilize tannase from Aspergillus niger.CLEAs-TA was precipitated by 80% ammonium sulfate solution for 30 min at 0 ℃,then the aggregates were cross-linked by 1.5% glutaraldehyde solution.The obtained cross-linked tannase aggregates remained 47.33% of total enzyme activity.Its optimum reaction temperature and pH value,react propyl gallate（PG） to gallate acid（GA）were 50 ℃,pH 4.5 respectively.Compared to the free tannase,the CLEAs-TA had higher affinity to the substrate.The conversion rate was 32.86% when cross-linked tannase aggregates were employed to GA from PG for 6 times.It shows the CLEAs-TA had further application in hydrolysis PG to GA in food industry.
出处
《食品与机械》
CSCD
北大核心
2012年第1期154-158,共5页
Food and Machinery
关键词
单宁酶
交联酶聚集体
无载体固定化
没食子酸丙酯
应用
tannase
cross-linked enzyme aggregates
carrier-free immobilization
propyl gallate
application
