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Coriolopsis trogii and Cerrena unicolor were investigated for laccase production in submerged fermentation with different nutrient medium containing metal ions and lignocellulosic materials. The maximum laccase activity of C. trogii Han751 was 8584.44 ± 98.45 U/L and was obtained from nutrient medium 7. However, the maximum laccase activity of C. unicolor Han 849 was 16144.26 ± 635.30 U/L from nutrient medium 9. Thus, the capacity of secreting laccase of C. unicolor Han 849 was superior to that of C. trogii Han751. Different fungal species have different medium components suitable for laccase production. The content of CuSO4·5H2O and MnSO4 in nutrient medium with the concentration of 0.25 g/L and 0.151 g/L, respectively, was more beneficial to C. trogii Han751 secreting laccase. However, the vital components of nutrient medium that contribute to the laccase activity of C. unicolor Han 849 were corncob, glucose, and CuSO4·5H2O, with the corresponding concentrations of 1 g/flask, 5 g/L, and 0.25 g/L, respectively. The results will contribute to the development of new methods to produce low-cost laccase.

Lignocellulosic biomass is widely used in the field of laccase production because it has the advantages of low price and easy availability. Thus, a comparative analysis was performed of the laccase secretion ability of five white-rot fungi in submerged fermentation using single or mixtures of lignocellulosic biomass. Maximum laccase activity of Trametes gibbosa An 360, Vanderbylia fraxinea An 369, Perenniporia pyricola Han 202, Coriolopsis trogii Han 474, and Trametes versicolor Han 1504 was 55.83 ± 0.28 U/L on the mixture of corncob and cottonseed hull, 77.96 ± 1.60 U/L on corncob, 443.33 ± 15.49 U/L on corncob, 686.57 ± 16.49 U/L on corncob, and 162.04 ± 11.33 U/L on cottonseed hull. The mixed lignocellulosic material effectively improved the laccase activity of T. gibbosa An 360 compared with other fungal strains. However, the presence of corncob contributed to the secretion of laccase activity for V. fraxinea An 369, P. pyricola Han 202, and C. trogii Han 474. Meanwhile, cottonseed hull was conducive to the secretion of laccase of T. versicolor Han 1504. Laccase activity of P. pyricola Han 202 was very stable throughout most of the fermentation time. The results from this study provide new methods and increase fungal strains to improve laccase activity. [ABSTRACT FROM AUTHOR]

Laccase activity secreted by Pleurotus eryngii Han 1787 and Lentinus edodes Han 1788 grown on six types of agroindustrial wastes was investigated. Maximum laccase activity of P. eryngii Han 1787 on Ulmus pumila, Juniperus formosana, Pinus tabuliformis, cottonseed shell, corncob, and leaf of corncob was nearly 5.77-fold, 2.37-fold, 2.78-fold, 2.81-fold, 11.53-fold, and 6.73-fold higher than that of L. edodes Han1788 on corresponding agroindustrial wastes. In general, the capacity of secreting laccase of P. eryngii Han 1787 was superior to that of L. edodes Han 1788. Furthermore, laccase activity of P. eryngii Han 1787 on the leaf of corncob, the corncob, Ulmus pumila, and Juniperus formosana was relatively stable during the whole fermentation process. Different fungi showed different preferences in different agroindustrial wastes to secret laccase on whole fermentation stage. The presence of leaf of corncob was useful for improving laccase activity of P. eryngii Han 1787, while L. edodes Han 1788 was more preferred to produce laccase along with the presence of Juniperus formosana. These results were preliminary conducive in laying the foundation for increasing industrial laccaseproducing strains and producing low-cost laccase. [ABSTRACT FROM AUTHOR]

The laccase activity of three cultivated Pleurotus strains was investigated using different lignocellulosic biomasses for solid-state fermentation. The lignocellulosic biomasses were Sophora japonica, Salix babylonica, Populus beijingensis, and Pinus tabuliformis, which were selected because of their laccase producing ability and low cost. The maximum laccase activities from P. ostreatus Han 1189, P. citrinopileatus Han 1192, and P. eryngii Han 1205 using Sophora japonica were 768.74 U/L ± 11.25 U/L, 144.77 U/L ± 9.70 U/L, and 200.42 U/L ± 6.85 U/L, respectively. The three species of Pleurotus showed consistency in having a preference of hardwood to secret laccase under solid-state fermentation when facing hardwood and softwood as substrates. Furthermore, the presence of Sophora japonica was beneficial to improving the laccase activity for three Pleurotus strains. The capacity of the laccase secretion of P. ostreatus Han 1189 was superior to the capacity of P. citrinopileatus Han 1192 and P. eryngii Han 1205. The discovery was helpful for obtaining new highproducing strains and suitable wood materials, as well as expanding these high-producing strains for industrial applications to obtain high laccase activity, high laccase yield, and low cost laccase. [ABSTRACT FROM AUTHOR]

Laccase has huge potential application in all aspects of biotechnology due to the ability of laccase to oxidize a wide range of phenolic and nonphenolic compounds. The future success of such applications requires large amounts of laccase with low costs. White-rot fungi are important groups of laccase production. In this study, three white-rot fungi, Phlebia acerina Han 618, Trametes hirsuta Han 726, and Coriolopsis trogii Han 751, isolated from a native North China habitat, were identified by the method of molecular biology and preliminary screening of the ability of laccase-production by guaiacol selection medium. Then they were fermented on different lignocellulosic biomass. Three species showed consistency in preference of lignocellulosic biomass, and the presence of stalk of Sorghum bicolor was more suitable for secreting laccase. The capacity of laccase secretion from different species was significantly different. The capacity of secreting laccase of C. trogii Han 751 was superior to that of P. acerina Han 618 and T. hirsuta Han 726. The discovery of a new strain with superior capacity of secreting laccase and suitable lignocellulosic biomass were helpful for laying a foundation for the optimization of the fermentation conditions for the highest laccase production, the isolation and purification of laccase, and the industrial application of laccase. [ABSTRACT FROM AUTHOR]