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Background The co-transformation of solid waste of natural and anthropogenic origin can be carried out through solid-state-fermentation systems to obtain bio-products with higher added value and lower environmental impact. Methods To evaluate the effect of Pleurotus ostreatus on co-transformation of oxo-degradable low-density polyethylene (LDPEoxo) sheets and lignocellulosic biomass (LCB), were assembled two 0.75 L microcosm systems in vertical (VMS) and horizontal (HMS) position. The pre-treated sheets with luminescent O2 plasma discharges were mixed with pine bark, hydrolyzed brewer’s yeast and paper napkin fragments and incubated for 135 days at 20 ± 1.0 °C in the presence of the fungus. With the co-transformation residues, biochar (BC) was produced at 300 ± 1.0 °C (BC300) for 1 h, then used to carry out adsorption studies, using the malachite green dye (MG) at pH 4.0, 7.0 and 9.0 ± 0.2. Finally, the biochar was the substrate for the germination of carnation seeds (Dianthus caryophyllus) and Ray-grass (Lolium sp.) in vitro. Results For HMS, the decrease in static contact angle (SCA) was 63.63% (p = 0.00824) and for VMS 74.45% (p = 0.00219), concerning the pristine. Plastic roughness in VMS was higher (26%) concerning the control. Throughout the 135 days, there were fungal growth and consequently laccase (Lac), manganese peroxidase (MnP) and lignin peroxidase (LiP) activities. During the first 75 days, CO2 production increased to 4.78 ± 0.01 and 4.98 ± 0.01 mg g-1 for HMS and VMS, respectively. In MG adsorption studies, the highest amount of the colourant adsorbed at both pH 4.0 and 7.0 ± 0.2. Conclusions Finally, the biochar or the biochar enriched with low concentrations of plant growth-promoting microorganisms and inorganic fertilizer favours the germination of Dianthus caryophyllus and Lolium sp., seeds.

Los residuos líquidos producidos al elaborar tinciones biológicas contienen mezclas de compuestos químicos y microorganismos, que generan un elevado impacto ambiental si no son tratados adecuadamente. Por esta razón, en el presente trabajo se evaluaron a Pleurotus ostreatus, Trametes versicolor, Enterobacter xianfangensis, Pseudomonas azotoformans, Pseudomonas sp., Bacillus subtilis y Pseudomonas fluorescens, para el tratamiento de un residuo líquido que contenía colorantes trifenilmetánicos y azóicos, a escala de laboratorio. Inicialmente, se seleccionaron las cepas con menor efecto antagónico y se determinó su potencial para producir las enzimas Lacasa, Manganeso Peroxidasa y Lignino Peroxidasa, al emplear sustratos inductores y mezclas de colorantes. Para el consorcio fúngico/bacteriano la disminución del color y demanda química de oxígeno fueron del 99 % y 70 % a las 96 h. La remoción de estos parámetros se relacionó con la interacción positiva entre las poblaciones de hongos, bacterias y la producción de enzimas ligninolíticas, obteniendo valores a las 96 h de 7.0 y 14.0 unidades logarítmicas para hongos y bacterias, con unas actividades enzimáticas de 75 U/L, 205 U/L y 0.63 U/L para Lacasa, MnP y LiP, respectivamente.

Modelado de la biodegradación en biorreactores de lodos de hidrocarburos totales del petróleo intemperizados en suelos y sedimentos (Biodegradation modeling of sludge bioreactors of total petroleum hydrocarbons weathering in soil and sediments)