耐高温胶原蛋白酶菌株的筛选和产酶条件优化

Screening of thermostable collagenase strain and optimizing conditions for enhancing thermostable collagenase production

以透明圈法、Azocoll法和16S r DNA,分离及鉴定耐高温、嗜中性和产胶原蛋白酶的菌株,并利用单因素和正交实验进行产酶条件优化,以提高其胶原蛋白酶活力。结果表明,8株耐高温、嗜中性和产胶原蛋白酶的菌株被选出。其中,胶原蛋白酶活力最高的菌株鉴定为Bacillus glycinifermentans。对B.glycinifermentans的产酶条件进行优化,确定了其最佳产酶条件为培养温度50℃、p H8.0、培养时间16 h、种龄10 h、装液量100 m L和接种量5%。条件优化后使其胶原蛋白酶活力由1.0215 U/m L提高至(5.97±0.52)U/m L。成功筛选到的目标菌,经过条件优化使其最大酶活力提高了4.8倍,为后续鱼骨的高效发酵提供了基础。

To screen and identify a thermostable, neutrophilic and collagenolytic strain by transparent circles, Azocoll method and 16 S r DNA, and optimize the fermentation conditions by the means of single factor experiments and orthogonal test to improve the production of thermostable collagenase. The results showed that eight thermostable, neutrophilic and collagenolytic strains obtained. The strain with the maximum thermostable collagenase production was identified as Bacillus glycinifermentans. Bacillus glycinifermentans’ optimal conditions for the maximum thermostable collagenase production were as follows： the culture temperature was 50 ℃, the initial p H was 8.0, the culture time was 16 h, the inoculum age was 10 h, the culture volume was 100 m L, the inoculum size was 5%, and the thermostable collagenase production developed from 1.0215 U/m L to（5.97±0.52）U/m L after optimizing enzymeproducing conditions. A target strain was isolated successfully and the thermostable collagenase activity was enhanced 4.8 times after optimization of fermentation conditions. These results could provide basic data for fish bone fermentation.