黑毛茶中产单宁酶真菌的筛选及产酶条件研究

摘要

In this study,screening of the tannase-producing fungi from raw dark tea by the medium plate riched in tannins acid was investigated,and the strains were identified as Aspergillus niger .The fermentation conditions and culture medium composition of strain WC-2 were optimized.The optimum conditions were as fol-lows:dullnut dregs content of 80%,1%α-lactose as additional carbon source,0.5% ammonium nitrate as addi-tional nitrogen source,fermentation temperature of 37 ℃,fermentation time of 72 h.Under above conditions, the enzymatic activity of tannase reached 27.06 U·g-1 .%采用富含单宁酸的平板培养基对黑毛茶中产单宁酶的真菌进行筛选，经纯化后初步鉴定该菌为黑曲霉，并对其中一株黑曲霉 WC-2产单宁酶的发酵条件以及发酵培养基的组成进行了优化。优化后的条件为：五倍子渣含量80％，外加碳源为α-乳糖、添加量1％，外加氮源为硝酸铵、添加量0.5％，发酵温度37℃，发酵时间72 h。在此条件下，单宁酶活力最高达到27.06 U·g－1。