摘要
以米曲霉1-7.3为出发菌株,通过紫外诱变,采用含有不同制霉菌素药物浓度的PDA培养基,初筛得到生长速度快、孢子颜色和菌落形态发生变化的菌株125株。通过制曲复筛进一步得到了一株综合酶系优良的目标菌株80110,该菌株产生的酸性蛋白酶和中性蛋白酶的酶活力较之1-7.3分别提高了230.10%和17.50%,糖化酶活力较之传统生产菌株3.042高出15.10%。用80110、1-7.3和3.042三种菌株进行酱油低盐固态发酵比较,80110发酵得到的酱油,总氮含量和氨基态氮含量都明显高于1-7.3和3.042。
Aspergillus oryzae 1-7.3 as the original strain was mutagenized by UV rays and screened with PDA medium containing different concentrations of the Nystatin as selecting pressure. We had primary screened 125 mutants which grow faster and change in the color of spore and colonial morphology. A multienzyme system modified objective mutant 80110 was obtained by the secondary screening of koji--making. It can product acidic protease and neutral protease in an increasing ratio of 230. 10% and 17.50% respectively as comparing with strain 1-7. 3 . Besides, its glucoamylase activity is 15.10% higher than 3. 042, which is often used as the classical producing strain. In low--salt solid--state fermentation of soy sauce, the total nitrogen and amino nitrogen produced by 80110 were obviously higher than those by 1-7.3 and 3. 042.
出处
《中国调味品》
CAS
北大核心
2009年第9期57-60,共4页
China Condiment
基金
国家科技支撑计划2007BAK36B03
2008BAI63B06支持项目
关键词
米曲霉
紫外诱变
蛋白酶
低盐固态发酵
Aspergillus oryzae
protease
UV mutagenesis
low-- salt solid-- state fermentation
