漆酶(Laccase,EC 1.10.3.2)属于蓝色氧化酶家族的一种多酚氧化酶,是重要的本质纤维( lingocellulose)降解酶之一(Bertrand et al.,2002).漆酶能催化降解多种芳香族化合物特别是酚类物质(Solomon et al.,1996).由于漆酶具有430～790mV氧化还原电位(Shleev et al.,2003),能够将分子氧直接还原为水,在没有H2O2和其他次级代谢产物存在下,只要存在溶解氧,就可直接氧化底物(韩晓磊等,2005).因此,漆酶广泛用于生物制浆、生物漂白、废水处理等工业过程中(曾涛等,2009).目前在工业应用中提高酶活力、降低酶成本仍然是研究热点.研究表明担子菌等某些高等真菌能够分泌漆酶,通过真菌发酵产漆酶受到多方面因素的影响(如培养基中碳源、氮源的选择及诱导物、底物的浓度等),因此培养条件的研究变得极为重要.%We aimed at revealing the effect of different culture conditions on the laccase activity of Leptographium qinlingensis. Single-factor experimental design was used for different carbon sources, nitrogen sources, Cu 2+ and substrate concentration, combined with the guaiacol method for determining laccase activity, and analysis of variance was used to analyze effects of the different culture conditions on the laccase activity of L. qinlingensis using SAS ( V8.1). The results showed that laccase activity of L. qinlingensis was significantly increased by maltose ( as carbon source) and yeast ( as nitrogen source). The laccase activity was induced by 0. 6 mmol ·L-1 copper ions and reached 292. 36 U · L-1 in the medium containing the Cu 2+ , however, the laccase activity was inhibited by copper ions exceeding 0. 9 mmol·L-1 . Furthermore, the laccase activity was induced by phloem powder of host trees (Pinus armandii). The peak of laccase activity occurred on the 11 d of culture. Different culture conditions had remarkable effect on laccase activity of L. qinlingensis. The maximum laccase activity was 681. 82 U·L-1 when being cultured in the medium containing maltose as carbon source, yeast as nitrogen source, 0. 6 mmol·L-1 Cu2+ and 6 g·L -1 phloem powder of host trees on the llthd.
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