摘要
为了促进蛋白酶的生产及应用,开展了从海水白鲳鱼肠道中筛选蛋白酶高产菌以及相关研究.经平板筛选和摇瓶发酵筛选,获得一株蛋白酶高产菌种EF21,该菌种被鉴定为蜡样芽胞杆菌(Bacillus cereus).通过产酶条件的初步研究,优选蛋白胨为菌种EF21产蛋白酶的最佳氮源,并确定产酶的最佳初始pH为7.5,最佳温度为20℃,最佳时间为64 h.在最佳条件下,发酵液中蛋白酶活力达1 292 U/m L.相对于文献报道的数据,菌种EF21低温环境中具有较强的产酶能力,具有一定的应用潜力.经过初步分析,菌种EF21在低温下良好生长情况与其来源于海洋环境有关,同时,由于EF21的16S rDNA序列与NCBI数据库中菌种的最大同源性仅为97%,可能是新发现的微生物菌种,今后通过开展毒性试验、所产蛋白酶的酶学性质以及发酵条件的优化方面的深入研究,可以进一步促进工业化应用.
To promote the protease production and application,related research were carried out to isolate strains having ability of protease-producing from gastrointestinal tract of seawater white pomfret. Using plate screening and shake flask fermentation,a protease high-yield strain EF21 was obtained and identified as bacillus cereus.The results of the enzyme-producing conditions showed that peptone was the optimum nitrogen source for protease production. At the same time,the optimal conditions for the protease production was the initial p H of7.5,temperature of 20 ℃ and culture time of 64 h. Under the optimum conditions,the highest protease activity of fermentation broth was reached to 1 292 U/m L. Strain EF21 possesed strong enzyme-producing capability under low-temperature environment maybe as a result of its screening source from marine environment.Moreover,the homologous analysis of 16 S r DNA sequences between the EF21 and strains of NCBI database was only 97%,so EF21 possibly can be found as a new microbial species. In conclusion,further study need to do in order to promote the industrial application of strain EF21,including toxicity test,enzymology properties and optimizing fermentation conditions
出处
《河南工业大学学报（自然科学版）》
CAS
北大核心
2015年第6期37-41,50,共6页
Journal of Henan University of Technology：Natural Science Edition
基金
广东省高层次人才项目(粤财教2013[246]号)
省部产学研结合项目(2012B091000040)
广东轻工职业技术学院自然科学启动基金项目(KJ201307)
创新强校工程专项资金自主创新能力提升项目(2A30305
1A20201)
关键词
蛋白酶
筛选
鉴定
产酶条件
protease
screening
identification
enzyme-producing condition
