重组里氏木霉产漆酶及其对2,4,5-三氯酚的高效降解  

Laccase produced by recombinant Trichoderma reesei and its application in high-efficiency degradation of 2,4,5-trichlorophenol

作　　者：周哲浩 夏颖[1] 夏黎明[1] ZHOU Zhe-hao;XIA Ying;XIA Li-ming(Key Laboratory of Biomass Chemical Engineering of Ministry of Education,College of Chemical and biological engineering,Zhejiang University,Hangzhou 310027,China)

机构地区：[1]浙江大学生物质化工教育部重点实验室浙江大学化学工程与生物工程学院

出　　处：《高校化学工程学报》2019年第4期864-871,共8页Journal of Chemical Engineering of Chinese Universities

基　　金：国家自然科学基金(21676247)

摘　　要：漆酶-介体系统在有机污染物治理方面具有较高应用潜能。2,4,5-三氯酚是一种检出率较高的氯酚类污染物,毒性强且难以自然降解,对环境和人类健康危害严重。以水稻秸秆作为底物,对重组里氏木霉进行固态发酵,第12 d滤纸酶活力及漆酶活力分别可达116.96和10.15IU×g^-1,秸秆失重率可达54.73%。利用所产漆酶对土壤污染物2,4,5-三氯酚进行降解试验,探究了5种介体(香草醛、丁香醛、丁香酸、HBT、ABTS)对降解反应的影响,发现天然介体丁香醛可有效促进漆酶降解2,4,5-三氯酚,降解率为86.42%。随后对漆酶-丁香醛催化系统进行优化,考察了不同漆酶用量、丁香醛用量、pH和温度对降解2,4,5-三氯酚反应的影响。在适宜反应条件:漆酶用量0.2 IU·m L^-1,丁香醛用量0.2mmol·L^-1,pH 4.6,60℃,反应180 min后2,4,5-三氯酚降解率达到90.11%。这一研究结果对于秸秆综合利用及漆酶-天然介体系统在2,4,5-三氯酚等土壤有机污染物高效治理方面具有重要的促进作用。Laccase mediator systems show great potential in organic pollutants treatment. 2,4,5-trichlorophenol is a chlorophenolic pollutant with high detection rates. It is highly toxic and difficult to be degraded naturally, which causes serious problems to the environment and human health. In this work, solid-state fermentation of recombinant Trichoderma reesei was performed using rice straw as substrate. At the 12th day of fermentation, the filter paper activity and laccase activity reached 116.96 IU·g^-1 and 10.15 IU·g^-1, respectively, and the mass loss rate was up to 54.73%. The effects of five mediators (vanillin, syringaldehyde, syringic acid, HBT, ABTS) on the degradation reaction of 2,4,5-trichlorophenol were investigated using the laccase produced by recombinant T.reesei under solid-state fermentation. The results show the natural mediator syringaldehyde could effectively promote laccase-catalyzed degradation of 2,4,5-trichlorophenol with degradation rate of 86.42%. The laccase-syringaldehyde system was optimized regarding laccase dosage, syringaldehyde dosage, pH, and temperature. The appropriate conditions for 2,4,5-trichlorophenol degradation are: laccase dosage 0.2 IU·mL^-1, syringaldehyde dosage 0.2 mmol·L^-1, pH 4.6 and 60℃. The degradation rate reached 90.11% after 180 min. The results are important in promoting laccase-natural mediator system in the treatment of soil organic pollutants such as 2,4,5-trichlorophenol.

关 键 词：漆酶 2 4 5-三氯酚 天然介体 丁香醛 

分 类 号：Q814[生物学—生物工程]