果胶酶高产菌株AspT7的分离及筛选鉴定

Screening and Identification for a High-yield Pectinase-producing Strain AspT7

用3种分离培养基培养供试菌株黑曲霉Ja,分别观察菌落生长情况,通过测量透明圈大小定性比较聚半乳糖醛酸酶活力大小,确定溴酚蓝平板培养基为较好的分离培养基。从土壤样本中通过富集培养、驯化、溴酚蓝平板初筛和摇瓶复筛,筛选出1株高产聚半乳糖醛酸酶的菌株AspT7,产聚半乳糖醛酸酶活力达到了6.5万U/mL,经初步鉴定为黑曲霉,将其命名为Aspergillus niger AspT7。

Aspergillus niger Ja was cultured in three different isolation mediums, and the growth of these colonies were observed separately. The enzymatic activity of polygalacturonic acid enzyme was compared qualitatively by measuring Dp/Dc of transparent circles, and bromophenol blue medium was chosen as a better isolation medium. A high - yield polygalacturonic acid enzyme strain, As- pT7, was selected from natural soil through enrichment culture, acclimating, bromophenol blue medium screening and shake flask rescreening. Its enzyme activity of polygalacturonase - producing reached 65000 U/mL. It was preliminary identified as Aspergillus niger, and named as Aspergillus niger AspT7.