褐藻胶裂合酶高产菌株的筛选及其发酵产酶条件优化

Screening of Alginate Lyase Synthase Producing Strain and Optimization of Its Fermentation Conditions

摘要: 通过系统的菌种选育方法，从样品的采集开始，到样品处理，目标菌驯化富集，再到高产菌株的初筛，复筛，最优菌株发酵产酶条件优化等步骤，最终从海洋藻类马尾藻中选育出1株酶活力很高的产褐藻胶裂合酶菌株，初步鉴定为一种革兰氏阳性细菌。该菌株在培养基配方为：褐藻酸钠0.8%，玉米浆干粉0.9%，硫酸铵0.3%，氯化钠3%，磷酸氢二钾0.2%，硫酸镁0.05%，余量为自来水，用氢氧化钠调节初始pH7.2，培养工艺为：150 ml三角瓶装液50 ml进行恒温振荡培养，培养温度全程控制在30℃，摇床转速设定在180 r/min的条件下，好氧发酵18~24 h酶活高达580 U/ml左右。另外通过实验鉴定该菌株所产的酶为胞外酶，具有非常好的研究应用价值。

Abstract: Through systematic method of strain selection, from sample collection to sample treatment, by target bacteria acclimatization and enrichment, then high-yield strain screening, re-screening, optimization of fermentation conditions for enzyme production of the optimal strain and other steps, finally, a strain with high alginic acid degradation enzyme activity was selected from marine algae. It was initially identified as Gram-positive bacteria. The strain was formulated in the medium as: Sodium alginate 0.8%, corn pulp 0.9%, ammonium sulfate 0.3%, sodium chloride 3%, potassium bisphosphate 0.2%, magnesium sulfate 0.05%. The rest is tap water. The initial pH 7.2 was adjusted with sodium hydroxide. The culture process is: 150 ml triangular bottle liquid 50 ml for constant temperature oscillation culture, the culture temperature is controlled at 30˚C, and the rocker speed is set at 180 r/min. The enzyme activity of aerobic fermentation after 18 - 24 h is up to 580 U/ml or so. In addition, the enzyme produced by the strain was experimentally identified as an extracellular enzyme. It has a very good research and application value.