耐热β-葡聚糖酶产生菌AS35产酶条件的研究

Study on fermentation technology of thermostable β-glucanase by strain AS35

本试验对枯草芽孢杆菌(Bacillus subtilis)AS35产β-葡聚糖酶的发酵条件进行优化研究。单因素实验结果表明:该菌产β-葡聚糖酶的最佳碳源为麦糟粉,添加量为3.0%(w/v),最佳麦糟粉颗粒直径为0.5mm左右;最佳氮源为蛋白胨,添加量为0.8%(w/v);最佳培养基初始pH为7.0;最佳摇瓶装液量为50mL/250mL三角瓶;最佳发酵温度为36℃。在上述优化条件下,以接种量10%(v/v)接种菌龄18h的种子于发酵培养基中,200r/min摇床培养60h,β-葡聚糖酶酶活达到32.5U/mL。同时,耐热性实验表明,该酶最适反应温度为65℃。

The fermentation conditions for producing β-glucanaseby Bacillus subtilis AS35 were investigated in this research.The results of single factor experiments showed that the optimum carbon sources was beer lees flour which the optimum particle sizes was about 0.5mm and the addition amount was 3.0%（w/v）;the optimum nitrogen sources was peptone and the addition amount was 0.8%（w/v）;the optimum medium volumn was 50mL/250mL in the flask;the optimum fermentation was 36℃and the optimal initial pH was 7.0.The β-glucanase activity was more enhanced which reached 32.5U/mL when strain ages 18h,inoculate 10%（v/v）,200r/min shaking bed cultivated 60h under the optimal fermentation conditions.Meanwhile,thermal stability experiments showed that the optimum temperature of β-glucanase was 65℃.