产聚半乳糖醛酸酶菌株Asperaillus niger M-8的筛选及产酶条件研究

从腐烂的葡萄干中定向分离筛选出适合液态发酵法生产聚半乳糖醛酸酶的菌株M-8,鉴定为黑曲霉(Asperaillus niger)。经摇瓶产酶实验可知,此菌株的产酶培养基组成及发酵条件为:果胶0.7%,NaNO30.1%,MgSO40.02%,FeSO40.001%,KH2PO40.03%,豆粉1.0%,马铃薯20.0%;培养温度28℃,初始pH7.0,装液量50mL/250mL,接种量7%(v/v),培养时间48h。在此优化发酵条件下,酶活力达964U/mL。该菌株生长周期短,产酶性状稳定,在食品领域有良好的应用前景。

Screen and Optimization of Polygalacturonase-producing Strain Aspergillus niger.M-8

A Polygalacturonase-producing strain was isolated from rotten raisin and was identified as Aspergillus niger.The optimal medium and the optimal fermentation condition were determined in this paper:pectic 0.7%,NaNO3 0.1%,MgSO4 0.02%,FeSO4 0.001%,KH2PO4 0.03%,bean powder 1.0%,potato 20.0%,culture temperature at 28℃,initial pH at 7.0,the culture medium volume at 50 mL,inoculum concentration of 7%(v/v),and the culture time of 48 h.Under the above conditions,the polygalacturonase activity reached maximal level:964 U/mL.As this strain showed some advantages in growth cycle and genetic stability,some potential applications could be found in food industries.