摘要
采用检测水解透明圈和测定蛋白酶活力的方法,从章鱼肠道中分离筛选出一株高产蛋白酶的菌株QDV-3,并对其产酶条件及酶学性质进行研究。结果表明:QDV-3菌株在以果糖为碳源,蛋白胨为氮源,培养基初始pH8.0,培养温度30℃的条件下振荡培养3.5d时,所产蛋白酶活力最高,Mn2+和Ba2+对菌株产蛋白酶有促进作用。所产蛋白酶在SDS-PAGE电泳上显示至少有5种蛋白酶,分子质量范围为32.4～124.2kD,蛋白酶的最适作用温度为50～60℃,最适作用pH值为9～11,在50℃条件下保温1h,剩余酶活力为95%,热稳定性较好。
A protease-producing bacterial strain was isolated and screened from the intestine of Octopus vulgaris by detecting hydrolysis circle of protease and its activity and identified as QDV-3. The optimal fermentation conditions for protease production and its enzymatic properties were also investigated. The highest protease production was achieved when strain QDV-3 was cultured at 30 ℃ for 3.5 d under shaking conditions in a medium at pH 8.0 with fructose as the carbon source and peptone as the nitrogen source. Meanwhile, protease production was improved in the presence of Mn2＋ and Ba2＋. At least five proteases were identified by SDS-PAGE, with molecular weights between 32.4 kD and 124.2 kD. The optimal reaction temperature and pH for the fermentation supernatant were 50-60 ℃ and 9-11, respectively. The fermentation supernatant exhibited high thermal stability, and 95% of its initial activity was retained after 1 h incubation at 50 ℃.
出处
《食品科学》
EI
CAS
CSCD
北大核心
2013年第1期189-193,共5页
Food Science
基金
山东省自然科学基金项目(ZR2011CM023)
关键词
产蛋白酶菌
蛋白酶
酶学性质
protease-producing bacterial strain： protease
enzymatic properties
