【摘要】 采用物理化学诱变方法,对纳豆菌进行复合诱变,以期筛选出纳豆激酶(NK)活力高的优良菌株。以实验室分离、筛选的纳豆菌NK-8作为出发菌,通过紫外线和氯化锂对其进行复合诱变,经过菌种的初筛和复筛,得到了酶活较出发菌提高2.2倍的菌株JN-14,并对初始菌株与诱变菌株进行了一系列的比较。实验进一步研究了该菌株产纳豆激酶的发酵过程,比较了不同的营养源与生长条件对菌株产酶的影响,优化、确定了菌株产纳豆激酶的产酶条件。更多还原

【Abstract】 The Bacillus natto was mutated by physical or chemical methods to improve nattokinase(NK) activity. An strain of B.subtilis NK-8, isolated from our laboratory, was mutated by UV rays and Lithium Chloride. A mutant JN-14 producing 2.2 times more nattokinase activity than its parent strain was obtained after preliminary screening and ambo-sieving. The influences of different nutrient sources and growth medium on JN-14 were studied, and the fermentation condition of producing nattokinase was optimized and determined.更多还原