Pycnoporus sp.SYBC-L3漆酶催化偶氮染料脱色

Decolorization of Azo Ayes by Laccase from Pycnoporus sp.SYBC-L3

为考察Pycnoporus sp.SYBC-L3漆酶Lac-L对偶氮染料的脱色、解毒效果,探究最佳的脱色反应条件,采用单因素分析方法研究了不同的反应条件对Lac-L催化3种偶氮染料(AR1、RB5、RV5R)脱色的影响,得到最佳处理条件,并通过比较被漆酶降解前后的染料对小麦和水稻发芽率及根、芽生长的影响,分析其毒性变化。结果表明:在以HBT为介体、反应温度50℃、pH分别为4.0(AR1,RV5R)和5.0(RB5)、漆酶用量1 U/mL、染料初始质量浓度分别为30 mg/L(AR1)和50 mg/L(RB5、RV5R)条件下,漆酶对3种偶氮染料的脱色效率最高,AR1和RV5R几乎完全降解,脱色率达到96.1%和97.8%,而RB5也有83.8%的脱色率。植物毒理实验表明,3种偶氮染料经漆酶降解后对小麦和水稻发芽率没有影响,对胚芽和根生长的抑制作用也有所降低。

The study aimed to investigate the decolorization and detoxification abilities of laccase from Pycnoporus sp.SYBC-L3 for azo dyes and optimize decolorization reaction conditions.The effect of different reaction conditions on the decolorization of three azo dyes catalyzed by Lac-L was studied by single factor analysis,and the toxicity change was investigated by comparing the effect of dyes before and after degradations on the germination and the growth of roots and buds of wheat and rice.The results showed that the optimum treatment conditions were as follow:HBT as mediator,reaction temperature at 50℃and pH at 4.0(AR1,RV5R)or 5.0(RB5),1 U/mL of laccase dosage,initial dye concentration at 30 mg/L(AR1)or 50 mg/L(RB5、RV5R).Under the optimized conditions,AR1 and RV5R were almost completely degraded with decolorization rates of 96.1%and 97.8%,while RB5 also had a decolorization rate of 83.8%.Plant toxicological experiments showed that the three azo dyes had no effect on the germination rate of wheat and rice after degraded by laccase,and the inhibition on the growth of germ and root was also reduced.