产岩藻聚糖硫酸酯酶微生物的筛选及产酶条件优化

Screening of Fucoidanase-producing Microorganisms and Optimization of Condition for Fucoidanase Production

利用岩藻聚糖硫酸酯酶对岩藻聚糖硫酸酯进行降解,是获得低分子质量岩藻聚糖硫酸酯的最佳途径,这对岩藻聚糖硫酸酯的结构研究和活性低聚糖的开发具有重要意义。本文通过次甲基蓝法从麦岛海域海水中筛选出1株岩藻聚糖硫酸酯酶的高产菌株MD3,经高效排阻色谱验证其具有降解岩藻聚糖硫酸酯的能力。优化的发酵产酶条件:发酵温度25℃,发酵初始pH8.0,250mL三角瓶装液50mL,摇床转速200r/min,发酵时间72h。优化后MD3产酶能力由2.1U/mL提高到4.0U/mL,为岩藻聚糖硫酸酯酶的生产及活性低聚糖的开发奠定基础。

Using fucoidan-degrading enzyme to digest fucoidan into oligosaccharides is the best method to analyze the structures of fucoidan and gain bioactive component. Fucoidanase-producing microorganisms are appropriate resources for preparing fucoidan-degrading enzyme. A fucoidanase-producing microorganism MD3 had been screened by the method of methylene blue from the seawater in the sea area of MaiDao. The ability of MD3 to degrade fucoidan and to produce fucoidanase was reconfirmed by the method of High-Performance Size Exclusion Chromatography （HPSEC） and SomogyiNelson. The conditions for fucoidanase production was optimized and the results were as follows： fermentation temperature 25 ℃, initial pH 8.0, the holding amount 50mL, speed of rotation 200r/min, cultured time 72h. Under the optimal fermentation conditions, the ability of fucoidanase-producing of MD3 increased to 4.0U/mL comparing to 2.1U/mL of initial conditions.