灵芝漆酶对直接蓝86的催化脱色性能

Decolorization of Direct Bule 86 catalyzed by laccase from Ganoderma lucidum

利用灵芝菌Ganoderma lucidum U-281漆酶对直接蓝86进行酶促氧化脱色,并对其降解机理进行了探讨。结果表明,染料-漆酶共反应体系在20～50℃及pH小于5.0范围内,直接蓝86均可脱色50%以上;漆酶对直接蓝86具有宽泛的浓度适应性,对300 mg/L的该染料仍具有耐受性。最优脱色工艺参数为温度40℃、pH 5.0、染料初始浓度200 mg/L、漆酶用量1 U/mL。在优化条件下,直接蓝863 h的脱色率达到54.54%,48 h脱色率达到91.54%。紫外-可见吸收光谱分析表明,漆酶的酶促氧化导致染料的分子结构产生了变化,是造成直接蓝86脱色的主要发生机制。

The enzymatic oxydative decolorization of Direct Blue 86 by laccase from Ganoderma lucidum U- 281 was studied. Besides, the degradation mechanism was discussed. The results show that in laccase-dye co-reaction system more than 50% of Direct Blue 86 is decolorized under conditions of 20℃ to 50℃ and pH value less than 5.0. Laccase has a wide range of adaptability towards the dye concentration and is endurable with 300 mg/L of Direct Blue 86. The optimum decoloration parameters are as follows ： 200 mg/L of initial dye concentration, 1 U/mL of laccase dosage, 40℃and pH 5.0 without rotation. Decoloration rates of Direct Blue 86 are 54.54% and 91.54% , respectively after 3 hours and 48 hours under the optimum conditions. UV-visible light spectrum analysis suggests that enzymatic oxidation results in changes of dye molecular structures, which is the primary mechanism causing decoloration of Direct Blue 86.