Oxidative enzymes secreted by white rot fungi can be applied in several technological processes within the paper industry, biofuel production and bioremediation. The discovery of native strains from the biodiverse Misiones (Argentina) forest can provide useful enzymes for biotechnological purposes. In this work, we evaluated the laccase and manganese peroxidase secretion abilities of four newly discovered strains of Trametes sp. that are native to Misiones. In addition, the copper response and optimal pH and temperature for laccase activity in culture supernatants were determined.The selected strains produced variable amounts of laccase and MnP; when Cu2+ was added, both enzymes were significantly increased. Zymograms showed that two isoenzymes were increased in all strains in the presence of Cu2+. Strain B showed the greatest response to Cu2+ addition, whereas strain A was more stable at the optimal temperature and pH. Strain A showed interesting potential for future biotechnological approaches due to the superior thermo-stability of its secreted enzymes.

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There is a need to explore lignocellulosic materials to select an adequate substrate for lignocellulolytic enzyme production. Utilization of some residues provides an opportunity to produce high yields of lignocellulolytic enzymes in a simple medium. The aim of the present work was to study the effect of wood flour as a carbon source on the cellulolytic and xylanolytic secretion of white-rot fungi native from Misiones. Fungi were incubated with 5 g Pinus sp. wood flour/L and 5 g Eucalyptus sp. wood flour/L as carbon sources in a reciprocal shaker at 80 rpm and 29ºC for 15 days. Total cellulase, endo-1,4-β-glucanase, β-glucosidase, cellobiohydrolase and endo-1,4-β-xylanase activities were determined in culture supernatants. Tested fungi showed high endo-1,4-β-xylanase activity between 6 and 12 days. Total cellulase showed the highest activity between 12-15 culture days. The test did not show differences among Pycnoporus sanguineus LBM 014, P. sanguineus BAFC 2126, Irpex lacteus BAFC 1171, Irpex sp. LBM 032, Irpex sp. LBM 034 and Lenzites elegans BAFC 2127, showing the highest activity for this group regard the others strains. I. lacteus BAFC 1171 was the strain with major endo-1,4-β-glucanase activity at day 9 (847 U/L). In the case of β-glucosidase and cellobiohydrolase, P. sanguineus BAFC 2126 was the strain with the highest activity between 12-15 culture days (18 U/L), and between 9-15 culture days (39 U/L), respectively. Wood flour proved to be a suitable carbon source to produce hydrolytic enzymes. I. lacteus BAFC 1171 and P. sanguineus BAFC 2126 have potential for cellulase production whereas P. sanguineus LBM 008 is a good endo-1,4-β-xylanase producer.

Los hongos de pudrición blanca, como Trametes villosa BAFC 2755, son los únicos organismos capaces de degradar eficientemente la lignina debido a que poseen un sistema enzimático oxidativo. Una de las enzimas más importantes en este proceso es la lacasa. Esta es una fenoloxidasa, que posee aplicaciones en varios procesos biotecnológicos incluyendo la deslignificación de la pulpa de papel, detoxificación de químicos recalcitrantes, degradación de compuestos policíclicos aromáticos, biorremediación de suelos y aguas contaminadas. El presente trabajo tuvo como objetivo evaluar el efecto del pH, la temperatura y el tiempo de incubación sobre el crecimiento y el potencial oxidativo de T. villosa BAFC 2755. Para ello se llevaron a cabo ensayos en medio de cultivo ME y se determinó la actividad lacasa. Para complementar el análisis de caracterizó una región del gen que codifica para una lacasa. Los resultados obtenidos mostraron que las condiciones que mejoraron la producción de biomasa no fueron las que soportaron la mayor actividad lacasa. Los máximos niveles de actividad se registraron a 25° C al día 14 para pH 5,5 siendo de 200 U/L. El perfil de isoenzimas de lacasa fue afectado por el pH, la temperatura y el tiempo de cultivo, encontrándose tres isoenzimas de 64 kDa, 123 kDa y 132 kDa. Además, se obtuvo una secuencia nucleotídica de 779 pb de un gen que codifica para lacasa, cuya secuencia proteica mostró identidad de 90% con secuencias pertenecientes al gen lacasa de otras especies de Trametes sp