【摘要】 该实验利用透明圈平板初筛,固态发酵测定酶活复筛的方法从黄酒麦曲中筛选到一株产淀粉糖化酶活力较高的菌株A17,其初始酶活为1835U/g干曲。根据其形态特征和ITS序列分析,该菌株为米曲霉(Aspergillus oryzae)。该糖化酶的最适温度为60℃,在30℃~55℃内酶比较稳定,最适作用pH值为4.0;Ca2+、Mg2+对酶有一定的激活作用,而Fe3+、Mn2+、Cu2+有较强的抑制作用。更多还原

【Abstract】 A starch-digesting glucoamylase producing strain A17 was isolated from wheat Qu by primary screening with transparent circle medium and rescreening with solid-state fermentation.The glucoamylase activity was 1835U/g medium(dry basis).Based on its morphological characteristics and ITS sequence analysis,the strain was identified as Aspergillus oryzae.The optimum conditions were as follows,temperature 60℃,pH 4.0.The enzyme was stable at 30℃~55℃,and can be activated by Ca2+ and Mg2+,while inhibited by Fe3+,Mn2+ and Cu2+.更多还原