The degradation dynamics of lignin and cellulose were analyzed by means of a solid state biodegradation experiment, using residues from the essential oil extraction of the Palo Santo tree (Bursera graveolens). As such, two native Xylaria spp. and an exotic mushroom Trametes versicolor were incubated on the spent substrate (Residues of B. Graveolens, BGR’s). The relatively high lignin and cellulose contents of the BGRs (9.1% and 19%, respectively) indicated the potential of this resource for the production of methane (biogas) and ethanol. However, the degradation of the lignin and cellulose content could be traced back to the relatively high activity of the enzymes laccase, cellulase, and xylanase, produced by the fungi. The results showed that laccase (30.0 U/L and 26.6 U/L), cellulase (27.3 U/L and 35.8 U/L) and xylanase (189.7U/L and 128.3 U/L) activities of Xylaria feejeensis and Xylaria cf. microceras were generally higher than T. versicolor (9.0 U/L, 29.5 U/L, 99.5 U/L respectively). Furthermore, the total carbon (TC: 47.3%), total nitrogen (TN: 1.5%), total phosphorus (TP: 0.2%) and total potassium (TK: 1.2%) dynamics were analyzed during the experiment and their importance for the degradation process highlighted. The results of this work might serve as guidance for future studies in dry forest areas, while furthering the understanding of the potential use of native fungi as ecologic lignocellulosic decomposers and for industrial proposes.

Se optimizaron condiciones para la producción de lacasa por Trametes villosa mediante la metodología de superficie de respuesta: relación C:N, nivel de Cu+2 (mM) y tiempo de fermentación. El extracto crudo se inoculó en vinaza diluida al 25% y se evaluó el cambio en algunos parámetros de calidad de agua residual. La optimización produjo un aumento en la actividad de lacasa de 2,86 veces con respecto al medio no optimizado. Se observó reducción en los valores de DQO, fenoles y color en la vinaza tratada de 46,33%, 73,98% y 52,87% respectivamente. El pH aumentó de 6,50 a 6,57 y la actividad enzimática mostró un marcado aumento en medio con vinaza. Se confirma la utilidad de la metodología de superficie de respuesta en la optimización de condiciones en procesos de fermentación. Selected conditions for laccase production by Trametes villosa were optimized by surface response methodology: C:N ratio, Cu+2 level (mM), and fermentation time. The crude extract was inoculated on 25% (v/v) diluted sugarcane vinasse and some residual water quality parameters were evaluated. A 2.86-fold increase in the enzymatic activity was obtained upon optimization. Reduction of COD, phenol and color values on the treated vinasse were 46.33%, 73.98% and 52.87% respectively. pH increased from 6.50 to 6.57 and laccase enzymatic activity in vinasse media increased considerably. The advantage of surface respond methodologies for optimization of fermentation conditions is confirmed.

Se evaluó el efecto de distintos niveles de cobre (II) sobre la velocidad específica de crecimiento de Trametes villosa en medio PDA 4% y medio PDA 4% con 25% (v/v) de vinaza. La velocidad específica de crecimiento se obtuvo a partir de los datos de área micelial y de la ecuación para el modelo logístico de crecimiento. Las mejores condiciones para el crecimiento micelial fueron PDA 4% con 25% (v/v) de vinaza y niveles de cobre divalente de 0,5 y 1,0 mM. Estos resultados indican que, de acuerdo con las condiciones de cultivo utilizadas, ambos suplementos favorecen el crecimiento micelial y entregan información esencial para el desarrollo de potenciales procesos de reutilización y valorización de la vinaza. The effect of different levels of copper (II) on the specific growth rate of Trametes villosa was evaluated. The strain was grown on 4% PDA and 4% PDA on a 25% (v/v) vinasse dilution. The specific growth rate was obtained from the mycelial area data which was modeled with the logistic equation. The best growth condition was 4% PDA in a 25% (v/v) vinasse dilution with copper (II) concentrations of 0.5 and 1.0 mM. These results indicate that under the utilized culture conditions, both supplements favor mycelial growth and provide essential information for potential processes of vinasse reuse and valorization.