No abstract

Pleurotus fungi are basidiomycetes that stand out in the degradation of recalcitrant organic compounds such as lignin derivatives and phenolic compounds. The aim of this study was to make a comparative evaluation of the capacity of the Pleurotus ostreatus POS 560 and Pleurotus floridae PSP1 fungi in the degradation of 2,4 and 2,6-dinitrotoluene (DNTs) in effluent from an explosive factory. The characterization of the effluent indicated 318 mg L-1 of DNTs, 246 mg L-1 of COD and toxicity factor for Daphnia magna corresponding to 8. The conduct of a multivariate study estimated the influence of the variables pH (5.0 and 6.0), co-substrate concentration (10 and 20 g L-1 of glucose) and species of the fungus Pleurotus (ostreatus and floridae) on the degradation of DNTs, indicating that the variables Fungus and [Glucose] were significant (p <0.05) presenting effects in the order of + 4.45 ± 0.26 and -1.14 ± 0.26, respectively. The reproduction of the best efficiency conditions (P. floridae; pH 6.0 and 10 g L-1 of glucose) in agitated flasks (100 rpm, 26oC) was able to carry out, within 14 days of treatment, the removal of organic matter and toxicity factor in levels on the order of 55 and 50%, respectively, in addition to the complete degradation of DNTs which occurred in the first 120 hours of treatment. In this period, the maximum activity of the peroxidase and Mn-peroxidase enzymes was also characterized, suggesting high potential of the bioprocess under study for remediation of effluents contaminated with nitroaromatic compounds.

This study characterized and evaluated the potential of a combination of treatment strategies for the removal of phenolic compounds, color, and ecotoxicity of an effluent generated by a laminated wood industry. The characterization of a sample of the effluent generated by the pine lamination process collected in an industry in the Southwest region of the state of Paraná confirmed the potential impact of the effluent, with emphasis on the high content of phenolic compounds (1,530 ±50 mg/L), color (2,159 ±30 units), significant acute toxicity (63% mortality of microcrustaceans Artemia salina) and low biodegradability (BOD/COD=0.53), which, if eventually released into receiving bodies, can cause irreversible and harmful effects to the aquatic microbiota. The treatment processes studied in this work involved catalytic ozonation mediated by ferrous catalytic material based on steel scale and biological process with Pleurotus Florida fungi, evaluated in an individual way and sequentially integrated as follows: Catalytic ozonation>>biological process and vice-versa. The best results were obtained by applying the sequence "catalytic ozonation>>biological process", which resulted in reductions of 96.2% in soluble lignin concentrations, 93.3% in color units and more than 99% reduction in total phenols, in addition to a low mortality rate of  A. salina (≈10%). In the integrated process, the application of catalytic ozonation before the biological process presents greater advantages because of the pre-decomposition process of recalcitrant compounds by the chemical action of catalytic ozonation, which can convert these compounds into biodegradable, facilitating the action of the biological process for the remediation of the effluent. Keywords: fungi, ozonation, phenols, wood lamination.