利用黑曲霉单宁酶酶法制取没食子酸的研究

STUDIES ON ENZYMATIC PRODUCTION OF GALLIC ACID WITH THE TANNASE FROM ASPERGILLUS NIGER

利用已有的 10株高单宁酶活性的菌株为起始菌 ,经活化分离选择 ,借助Ⅱ级发酵培养程序、生物转化、结合TLC分析进行筛选实验。最后选出具有高单宁酶活性的 1号和 5 0号菌株 ,开展了没食子酸 (GA)克量级生物转化法制备实验 ,结果表明 ,本酶法工艺是可行的 ,在发酵液中GA的浓度分别达到2 0 .6mg/ml和 2 1 3mg/ml,产品产率 (以从五倍子提取的单宁酸计 )达到 41 2 %和 42 6 % 。

In this dissertation,studies on the enzymatic hydrolysis of tannic acid extracted from Chinese gallotannin into gallic acid in aqueous media was reported by using Aspergillus niger tannase.Through several steps of selection,including two-stage formentation procedure,bioconversion screening,NO.1 and NO.50 were finally selected from 10 original strains Aspergillus niger.The gramme-grade preparation experiments of gallic acid in culture broth was done.The results shown that the activity of tannase selected two strains was high in this work,as the concentration of gallic acid were accumulated to 20.6 mg/ml and 21.3 mg/ml respectivlly during a period of 48 hours of bioconversion.