摘要
从腐烂的木薯中分离得到1株降解生淀粉能力较强的菌株ITBB FC2,经形态学鉴定和18S rDNA序列分析,初步鉴定属于黑曲霉（Aspergillus niger）。该菌株用2%生木薯粉培养基摇瓶,37℃,200 r/min培养3 d后,发酵液葡萄糖含量为970 mg/L,生淀粉酶活力为495.04 U/mL。采用固体产酶培养基（麸皮∶水=1∶1）培养,所得酶活力为6 330 U/g。酶反应最适pH为4.0~5.0。Ca2＋对酶活力有一定的促进作用。
Aspergillus niger strain ITBB FC2, isolated from decayed raw cassava root showed strong raw-starch-digrading-glucoamylase （RSDG） activity in liquid fermentation medium with 2% cassava flour. The crude enzyme had an activity of 495.04 U/mL and produced 970 mg/L of glucose in the 2% cassava flour fermentation medium when inculated at 37 ℃, 200 r/rain for 3 days, while it had an activity of 6 330 U/g in solid fermentation medium （bran：water=l：l）. The optimal pH was 4-5. 2 mmol/L. Ca^2＋ promoted the enzyme activity by 133.74%.
出处
《热带作物学报》
CSCD
北大核心
2012年第7期1239-1244,共6页
Chinese Journal of Tropical Crops
基金
科技部国际科技合作计划项目“热带生物质能源高效转化及综合利用”(No.2010DFA62040)
关键词
黑曲霉
生淀粉糖化酶
酶学性质
AspergiUus niger
Raw-starch-digrading-glucoamylase
Enzymatic characterization
