单宁酶产生菌的筛选和发酵条件研究

利用富集培养技术，从天然源分离得到具有较高单宁酶活性的黑曲酶Ｎｏ．１７株（ＡｓｐｅｒｇｉｌｕｓｎｉｇｅｒＮｏ．１７）．该菌株能把五倍子中的单宁酶法水解成没食子酸，在对Ｎｏ．１７株开展产酶条件和参数优化实验的基础上，进行了实验室酶法制备没食子酸试验，并获得产物浓度为１４．１ｇ／Ｌ的没食子酸，经大孔吸附树脂分离，最终净产率达到７０％．该样品经熔点测定、元素分析、ＴＬＣ、红外等理化方法分析检测，结果均与没食子酸标样一致

STUDIES ON SCREENING OF TANNASE PRODUCING STRAINS AND THEIR FERMENTATION CONDITIONS

Aspergillus niger No.17 with higher tannase activity was isolated by using enrichment culture technigue from natural resources. This strain was able to hydrolyze tannin from Chinese gallotannin into gallic acid(GA). Based on the studies on tannase producing conditions and optimal fermentation parameters of No.17, the preparation of GA was developed on laboratory scale. The results showed that the GA concentration was about 14.1 g/L, the net yield of GA was upto 70% by means of macroreticulate resin separation. Physical and chemical data of the product were determined, including melt point,element analyses, TLC and IR. These data were identical with the authentic GA.