Preliminary studies on the application of Trametes trogii crude extracts to the biobleaching of loblolly Kraft pulp

DA RE V, PAPINUTTI, VL, VILLALBA L, FORCHIASSIN F, LEVIN L

Madison, EUA

Congreso; 10 International Congress in biotechnology in the pulp and paper industry; 2007

Trametes trogii (BAFC 463), Coriolus versicolor var. antarcticus (BAFC 266) and Trametes villosa (BAFC 2755) are Argentinean white rot fungi that proved to be efficient ligninolytic enzyme producers in previous works. The aim of the present study was investigating the ability of their crude extracellular extracts for the biobleaching of loblolly Kraft pulp. The production of laccase, manganese peroxidase, endoxylanase and endoglucanase was also evaluated. Culture supernatants from T. trogii grown for 21 days in a synthetic medium with glucose and asparagine as carbon and nitrogen sources respectively, with the addition of 1 mM copper sulfate, produced manganese peroxidase (0.25 U/ml) and high levels of laccase (44 U/ml), and gave the best results when they were applied to biobleaching. After the enzymatic treatment, the requirement of hydrogen peroxide decreased, and the lightness of the pulp attained a value of 92.5%. Addition of known laccase mediators such as HBT, ABTS, and HBA did not improve the process.