Department of Biochemistry and Molecular Biology, BIOAGRO, Federal University of Viçosa, Viçosa, MG 36.570-000, Brazil.
Laboratory of Renewable Resources Engineering, Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN, 47907-2032, United States.
Enzyme Microb Technol. 2018 Feb;109:25-30. doi: 10.1016/j.enzmictec.2017.09.007. Epub 2017 Sep 19.
Cellulase and hemicellulase activities in a 1:1 ratio of enzymes extracted from Chrysoporthe cubensis and Penicillium pinophilum were evaluated in the presence of known monocomponent phenolic inhibitors and also with phenol mixtures derived from alkali pretreated sugarcane bagasse. The cellulolytic activities from C. cubensis:P. pinophilum displayed a much higher tolerance to phenolic inhibitors than equivalent enzyme activities obtained from Trichoderma reesei and Aspergillus niger. Enzymes from T. reesei and A. niger were deactivated at 0.3 and 1.5mg phenols/mg protein, respectively, as reported previously, while enzymes from C. cubensis:P. pinophilum resisted deactivation at 35mg phenols/mg protein. However, tolerance of xylanase with respect to phenols required the presence of laccase. Removal of laccase (enzyme) activity using sodium azide resulted in a 2x higher xylanase deactivation (from 40% to 80%). This paper identifies enzymes that are phenol tolerant, and whose adoption for lignocellulose hydrolysis could contribute to reductions in enzyme loading needed to hydrolyze alkali pretreated lignocellulosic substrates in the presence of lignin derived phenols.
从 Chrysoporthe cubensis 和 Penicillium pinophilum 中提取的酶以 1:1 的比例混合的纤维素酶和半纤维素酶活性，在已知的单一组分酚类抑制剂以及来自碱预处理甘蔗渣的酚混合物存在下进行了评估。与从 Trichoderma reesei 和 Aspergillus niger 获得的等效酶活性相比，来自 C. cubensis:P. pinophilum 的纤维素酶活性对酚类抑制剂具有更高的耐受性。如前所述，T. reesei 和 A. niger 的酶在 0.3 和 1.5mg 酚/mg 蛋白时失活，而 C. cubensis:P. pinophilum 的酶在 35mg 酚/mg 蛋白时仍能保持活性。然而，木聚糖酶对酚类的耐受性需要漆酶的存在。使用叠氮化钠去除漆酶（酶）活性会导致木聚糖酶失活增加 2 倍（从 40%增加到 80%）。本文鉴定了对酚类具有耐受性的酶，其在木质纤维素水解中的采用可能有助于减少在存在木质素衍生酚的情况下水解碱预处理木质纤维素底物所需的酶用量。
