贝壳状革耳菌诱变提高产漆酶能力及其生物漂白的研究  

Improving Laccase Activity of Panus Conchatus by Mutagenesis and Used for Biobleaching

作　　者：莫佳琳[1] 付时雨[1] 詹怀宇[1] 

机构地区：[1]华南理工大学制浆造纸工程国家重点实验室,广东广州510640

出　　处：《中国造纸学报》2006年第4期29-33,共5页Transactions of China Pulp and Paper

摘　　要：本研究从贝壳状革耳菌(Panus conchatus,是一株具有选择性降解木素的白腐菌)菌株出发,通过原生质体融合和紫外诱变技术处理,获得产漆酶酶活较高的诱变融合菌株,诱变株28-7的漆酶酶活高峰达17290 IU/L,比原始菌的酶活高峰2318 IU/L提高约7.5倍。诱变菌株分泌的漆酶预处理荻苇浆、麦草浆和芦苇浆,LQP浆和OLQP浆的白度较未经处理的高,卡伯值下降,黏度变化不大。经过漆酶/介体生物处理可提高纸浆的可漂性,对后续漂白有促进作用。实验结果初步证明,原生质体融合和紫外诱变技术可以作为改良白腐菌Panus conchatus的手段。Panus conchatus, a kind of white rot fungi, produces laccase with high yield, which degrades lignin selectively. Lacease has been used widely in many fields and it has an interest in enzyme engineering and environmental protection. However, the most important thing for us was to obtain the strains with higher laccase activity. The purpose of the study was to screen the strains with higher laccase activity, and then, the pulp was biobleached with these mutant strains. In this paper, the mutant strains with higher laccase activity were obtained by pretoplast fusion and ultraviolet mutagenesis. 19 mutant strains with higher laccase activity were obtained by screening and the highest laccase activity was 17290 IU/L, which was 7.5 times higher than that of the primary strain. In the experiment, three kinds of pulp were treated by laccase producing by mutant strains. Another bleaching sequence was I.accase/mediator biobleaching, i.e.I.accase/NHA treatment （L）, oxygen treatment （O）, chelating agent treatment （Q） and hydrogen peroxide bleaching（P）, the physical properties of the bleached pulp were improved in a certain extent. The brightness of LQP pulp and OLQP pulp was higher, Kappa value was lower and viscosity had a little decrease compared with the unbleaching pulp. The pulp bleaching perfommnce was improved comparatively after treatment by laccase/mediator system. It was proved that protoplast fusion and ultraviolet mutagenesis are the effective methods to improve laccase activity of Panus conchatus, and the results of our work are significant for the potential application of laccase.

关 键 词：漆酶 原生质体融合 紫外诱变 酶活 生物漂白 

分 类 号：Q55[生物学—生物化学]