摘要
目的从日本成品纳豆中筛选蛋白酶活性高、溶血栓活性显著的纳豆菌,并对筛选获得的菌株进行生物学特征分析。方法用梯度稀释法分离单菌落,然后根据所筛选菌株具有革兰氏染色阳性、淀粉酶活性、高蛋白酶活性、高纤溶酶活性等特征设计纳豆菌株的定向筛选方案。结果获得2株高蛋白酶活性、高纤溶酶活性的纳豆菌BN9和BN23;BN9液体培养物在接种后12 h进入对数生长期,24 h时菌体浓度和蛋白酶活性均达到最高,且生长延滞期的菌体呈长链状结构,对数生长期后期的菌体开始断裂为短杆状。结论采用定向筛选方案获得高溶血栓活性纳豆菌株的方法可行。
Objective To screen the interested strains with high proteinase activity and evident thrombolytic activity from natto products and analyze their biological character. Methods The single colonies were obtained by the gradient dilution method and the oriented screening program of Bacillus subtilis/natto strain was designed on the base of taxonomic characters such as Gram＇s positive, having high activities of amylase, proteinase and plasmin. Results Two strains, BN9 and BN23, were identified with high proteinase and plasmin activity. BN9 liquid culture entered into the logarithmic growth phase after being inoculated for 12 hours and bacteria concentration and proteinase activity reached up to the highest values 24 hours later after being inoculated. And the thalline was longcatenarian in the growth lag phase, then divided into short rod shape in the later logarithmic growth phase. Conclusion The oriented screening method for Bacillus subtilis/natto to obtain high thrombolytic activity is feasible.
出处
《食品与药品》
CAS
2007年第12A期21-23,共3页
Food and Drug
关键词
纳豆菌
定向筛选
生物学特征
Bacillus subtilis/natto
oriented screening
biological character
