摘要
【目的】优化枯草芽孢杆菌(Bacillus subtilis)BE-91生长及其胞外表达β-甘露聚糖酶的发酵条件。【方法】对影响菌株生长和发酵的主要因素(C源、N源、起始p H、温度等)进行单因素试验后,采用正交试验法研究B.subtilis BE-91生长培养条件和摇瓶发酵条件的优化组合。【结果】优化生长条件为:0.3%牛肉膏、0.2%酵母膏、0.1%葡萄糖、0.4%魔芋精粉、0.5%Na Cl,初始p H6.0、培养温度35°C;胞外表达β-甘露聚糖酶活力的摇瓶发酵条件优化组合为:0.7%魔芋精粉、0.4%大豆蛋白胨、0.1%(NH4)2SO4、0.5%Na Cl,发酵温度35°C和起始p H 6.0;优化条件下发酵10 h,β-甘露聚糖酶活力最高达432.4 IU/m L,比国内外已有相关菌株报道的发酵时间缩短了14-86 h,最高酶活力提高了5倍以上。【结论】B.subtilis BE-91生长与发酵周期短、胞外表达β-甘露聚糖酶的活力高,是酶制剂产业具有重大开发价值的菌种资源。
[Objective] We optimize the growth conditions of Bacillus subtilis BE-91 and its shake flask fermentation conditions producing extracellular β-mannanase. [Methods] Single-factor experiments were used to optimize the main factors （such as carbon source, nitrogen source, pH, temperature and so on） affecting the growth of B. subtilis BE-91 and its extracellular β-mannanase production in shake flask fermentation. Based on one-factor-at-a-time experiment, orthogonal tests were applied to obtain the optimal combination. [Results] The optimum growth conditions of B. subtilis BE-91 showed asfollows： 0.3% beef extract, 0.2% yeast extract, 0.1% glucose, 0.4% konjac powder, 0.5% NaCl, initial pH of 6.0, and culture temperature of 35 ℃. The optimum conditions for extracellularβ-mannanase production were as follows： 0.7% konjac power, 0.4% soybean peptone, 0.1% （NH4）2SO4, 0.5% NaCl, initial pH of 6.0 and fermentation temperature of 35 ℃. Under the optimized conditions, the highest extracellular β-mannanase production of B. subtilis BE-91 was 432.4 IU/mL in 10 h. Its extracellular β-mannanase production was more than 5-fold higher than that from other relevant strains reported, and the time appeared 14-86 h shorter than others. [Conclusion] B. subtilis BE-91 has advantage in short cultivation time and high extracellular production ofβ-mannanase, so it is the specious resources with potential use in the enzyme preparation industry.
出处
《微生物学通报》
CAS
CSCD
北大核心
2015年第12期2300-2307,共8页
Microbiology China
基金
国家创新工程项目(No.ASTIP-IBFC08)
国家863计划项目(No.2012AA022209D)
国家现代农业产业技术体系建设专项项目(No.CARS-19-E24)
