摘要
从实验室产壳聚糖酶菌株出发,研究壳聚糖酶的发酵培养基配方及发酵条件。结果表明,最佳的碳源是壳聚糖10 g/L、葡萄糖6 g/L,最佳的氮源是硫酸铵20g/L,最佳初始p H为7.0。摇瓶最佳培养条件是温度32℃,转速150r/min,装液量300/500m L。5L发酵罐培养结果表明,在搅拌速度为100r/min、通风比为0.75条件下,培养66h,可以得到酶活12.5 U/m L的酶液。酶液最佳的反应条件是p H 5.6、温度50℃,酶液长期存储需要采用-20℃冷冻,3天内短期存储可以4℃冷藏,酶活可以保留90%以上。壳聚糖酶的动力学分析表明,反应符合米氏方程,米氏常数Km为0.247g/L,最大反应速率Vm为10.65μmol/min。
The research on optimal fermentation mediums and conditions of a chitosanase producing bacterium was studied. The results showed that the best carbon source were powder chitosan 10 g/L, glucose 6 g/L, and the best nitrogen source was （NH4）2SO420g/L, and the optimal initial pH was 7.0. The optimal conditions of culture shaking were at 32℃, 150r/min shaking speed and shaking 300mL medium in 500mL flask.The optimal conditions of 5L fermenter were ： fermenter agitation 100 r/min and ventilation amount 0.751/（1· min）. Under the optimized conditions, the chitosanase activity could reach to 12.5U/mL after incubated for 66 hours. The optimum pH and temperature of the chitosanase were 5.6 and 50 ℃ . The chitosanase can maintain 90% activity within 30 days under -20 ℃, or within 3 days of 4℃ cold storage. The Michaelis-Menten parameters （Km）, maximum velocity （Vmax） of the enzyme were 0.247g/L, 10.65μmol/min at 50 ℃ and pH5.6.
出处
《中国食品添加剂》
北大核心
2017年第7期80-86,共7页
China Food Additives
基金
山东省科学院-无棣产学研协同创新基金
关键词
壳聚糖酶
发酵条件
发酵罐发酵
chitosanase
fermentation conditions
fermentor culture conditions
