Graduate Program in Environmental Biotechnology, Universidade Estadual de Maringá, Brazil.
Department of Biochemistry, Universidade Estadual de Maringá, Brazil.
Bioresour Technol. 2019 Oct;289:121655. doi: 10.1016/j.biortech.2019.121655. Epub 2019 Jun 15.
A single laccase with molecular weight of 41 kDa was produced by the white-rot fungus Oudemansiella canarii cultured on solid state fermentation using a mixture of sugarcane bagasse-wheat bran as substrate. The enzyme (5 U) was able to decolourize 80% of 50 mg/L Congo red within 24 h at 30 °C and pH 5.5. The relationship between the decolorization rate and dye concentration obeyed Michaelis-Menten kinetics, with K and V values of 46.180 ± 6.245 µM and 1.840 ± 0.101 µmol/min, respectively. Fourier transform infrared spectroscopy (FTIR) and mass spectrometry allowed to conclude that the laccase acts not only on the dye chromophore group, but also that it cleaves different covalent bonds, causing an effective fragmentation of the molecule. The action of the laccase caused a significant reduction in toxicity, as indicated by the Microtox test. In conclusion, O. canarii laccase could be useful in future biological strategies aiming at degrading azo dyes.
一株白腐真菌——canarii 被用于固态发酵，以甘蔗渣-麦麸混合物作为基质，产生了一种分子量为 41kDa 的单漆酶。该酶（5U）在 30°C 和 pH 值为 5.5 的条件下，24 小时内可将 50mg/L 的刚果红脱色 80%。脱色速率与染料浓度之间的关系遵循米氏动力学，K 和 V 值分别为 46.180±6.245µM 和 1.840±0.101µmol/min。傅里叶变换红外光谱（FTIR）和质谱分析表明，漆酶不仅作用于染料的生色团，还能切断不同的共价键，导致分子的有效断裂。微毒测试表明，漆酶的作用使毒性显著降低。综上所述，canarii 白腐真菌漆酶可用于未来旨在降解偶氮染料的生物策略。
