高产淀粉酶细菌的分离鉴定及产酶条件优化

从赊店老酒大曲中分离筛选产淀粉酶的细菌,通过碘熏蒸产生透明圈法进行初筛,淀粉酶活力测定进行复筛,结合菌落形态观察和16SrDNA同源序列分析以及生理生化对筛选获得的高产淀粉酶细菌进行鉴定,研究影响细菌产淀粉酶能力的单因素:碳源、发酵时间、初始pH、接种量,采用响应面优化确定最佳产酶条件。结果表明,6-10菌株为贝莱斯芽孢杆菌(Bacillus velezensis),通过响应面优化确定产酶工艺条件最佳为:发酵时间4d,初始pH 5,接种量10%。优化后产酶能力达到(164.37±3.25)U/mL,是优化前产酶能力的4.43倍,具有较强的产淀粉酶能力。

Isolation and identification of amylase bacterial and optimization of enzyme production conditions by response surface

The amylase-producing bacteria were isolated and screened from the old liquor of Dadian,and the retort was used to perform the preliminary screening by the iodine fumigation method,The amylase activity was measured by rescreening,combined with colony morphology observation,16S rDNA homologous sequence analysis,and physiological and biochemical screening.The high-yield amylase bacteria were identified to study the single factors affecting the ability of the bacteria to produce amylase,including carbon sources,fermentation time,initial pH and inoculum size,and the optimal enzyme production conditions were determined by response surface optimization.The results showed that strains 6-10 were Bacillus velezensis.The optimal conditions for enzyme production were determined by response surface optimization i.e.fermentation for 4 d,initial pH value at 5,and inoculum size at 10%,After optimization,the enzyme production capacity reached(164.37±3.25)U/mL,which increased by 4.43 times.