产漆酶真菌筛选及其固态发酵条件初步探究.docVIP

产漆酶真菌筛选及其固态发酵条件初步探究摘要：目的筛选产漆酶真菌，优化固态发酵培养基组成，研究粗酶的酶学性质。方法平板筛选获得菌株，通过测定漆酶活性优化培养基的组成。结果获得了固态发酵条件下产漆酶活性较高的菌株。优化后培养基的组成：豆粕和木屑比例1∶1，木糖0.5 %，酒石酸铵2.0 %，培养基含水量65 %。漆酶最适温度60 ℃，低于50 ℃时漆酶较稳定，最适pH 3.5，pH 6.5～9.0之间漆酶稳定性较好。结论得到了产漆酶活性较高的菌株，培养基优化后漆酶活性提高7倍。 关键词：漆酶；筛选；固态发酵；粗酶性质 中图分类号：Q554文献标识码：A文章编号：1672-979X(2009)01-0011-04 Screening of Laccase-Producing Fungal Strain and the Preliminary Study on the Solid-State Fermentation Conditions SHI Xiao-yan1, CAI Yu-jie1, WANG Zhi-xin1, LIAO Xiang-ru1*, ZHANG Da-bing2 (1. The Ministry of Education, Key Laboratory of Industrial Biotechnology, School of Biotechnology, Jiangnan University, Wuxi 214122 China; 2. Hanbon Science Technology Co. Ltd, Huai’an 223001, China) Abstract：Objective To Screen the laccase-producing fungi and optimize its solid-state fermentation medium as well as study the property of crude enzyme. Methods The strains wereobtained by plate screening and the optimization of medium was performed by measuring the activity of laccase. Results A fungal strain with a high laccase-producing activity was obtained under solid-state fermentation. The optimal medium contained: soybean meal and sawdust with the ratio of 1∶1, 0.5 % xylose, 2.0 % ammonium tartrate and 65 % moisture. The optimal temperature was 60 ℃ for laccase, and the laccase was stable at less than 50 ℃. The optimal pH value was 3.5, and the laccase was stable at pH 6.5～9.0. Conclusion A fungal strain with a high laccase-producing activity was obtained and the activity of laccase was increased 7 times with the optimization of medium. Key words：laccase; screening; solid-state fermentation; property of crude enzyme 漆酶（laccase，ρ-diphenol oxidase，EC 1.10.3.2）是一种结合多个铜离子的多酚氧化酶，能催化酚类、芳胺类、羧酸类、甾体类激素、生物色素、金属有机化合物和非酚类物质生成醌类化合物、羰基化合物和水。漆酶与抗坏血酸氧化酶和哺乳动物血浆铜蓝蛋白同源，都属于蓝色多铜氧化酶家族[1]。 漆酶能降解木素，可与有毒的酚类物质作用，还可降解苯氧基类除草剂及去除石油工业废水的毒性。漆酶用于食品加工可提高产量、效率和质量，而且不明显增加投资和生产成本，不产生有毒物质。如：用于提高果汁、果酒和啤酒的稳定性[2,3]；处理食品工业中产生的废水[4]；用于面包加工可增加面包体积，改善面包结构和柔软性，提高面团的机械强度、稳定性，降低面团黏性[5]。漆酶可特异降