ABSTRACT
In this study, growth and laccase production of Armillaria mellea and Trametes versicolor in solid-state fermentation were monitored using maize bran as a support, and surface secreted extract was used for synthetic dyes discoloration. The maximum laccase activity was obtained ca. 25 d of culture for both, but a higher specific activity of 751 U/mg for T. versicolor, vs. 487 U/mg for A. mellea was observed. The growth was monitored for 984 h by weight measurements. Laccase activity was determined using syringaldazyne as substrate. In addition, the discoloration of Remazol Brilliant Blue R (RBBR), Methylene Blue (MB), Brilliant Green (GB) and Congo Red (RC) was carried out at pH 5.4 and 4.5, (0.016 U/ml laccase activity) with raw extracts from both fungi, and commercial laccase from T. versicolor as control. In this work, T. versicolor and A. mellea were able to thrive, produce and excrete the enzyme laccase, while grown on maize bran. Synthetic dyes are differentially decolorated within small changes of pH values from 4.5 to 5.4.
