DECOLORIZATION OF TEXTILES DYES PERFORMED BY THE ENDOPHYTIC STRAIN Neofusicoccum sp. LGMF1505, ISOLATED FROM Illex paraguariensis (ERVA-MATE)

Endophytic fungi are a diverse and rich group of organisms capable to colonize many plants in different habitats and presents a wide enzymatic production. However, the distaining ability of this group of fungi is still somehow ignored. Neofusicocum genus comprehends endophytes and plant-pathogens and some strains are described producing ligninolytic enzymes as laccases. Laccases are enzymes widely applied in the degradation of recalcitrant polymers as lignin and used for bioremediation, in pulp and paper industry and textile dye decolorization. Considering enzymatic production, Neofusicoccum strains could represent a potential for biodegradation of textile dyes, which are very hazardous to the environment. The aim of the study was to evaluate the decolorization activity of the strain Neofusicoccum sp. LGMF1505, isolated as endophytic from Ilex paraguariensis "Erva-mate”, belonging to LabGeM culture collection of Universidade Federal do Paraná. The decolorization activity was calculated by the absorbance of the dye solution, using a spectrophotometer. The dye decolorization was evaluated after 15 days of growth in liquid minimal medium (LMM: 6.0 g NaNO3, 1.5 g, KH2PO4, 0.5 g KCl, 0.5 g MgSO4, 0.01 g FeSO4 7H2O, 0.02 g ZnSO4 7H2O, 10.0 g glucose, at pH 6.8) containing one of the textile dyes RB220, RR198 or RY107 (0.1 g L-1). Different culture portions were assayed to determinate the fraction responsible for the activity. Mycelia derived from 15 d culture in LMM were tested fresh, autoclaved or in the presence of sodium azide (laccase inhibitor) in a 1.1 mL solution of salt medium (SM: LMM without carbon and nitrogen sources) containing RB220 (0.1 g L-1) and left for 24 hours at room temperature. Supernatants were evaluated in the same way. The effect of simple and complex carbon sources (glucose and carboxymethyl cellulose) in different concentrations (5, 10 and 15 g L-1) was also evaluated. After 15 days, strain LMGF1505 greatly decolorized (80,2%) the RB220 dye. For RY107 and RR198 dyes, decolorization taxes were 50% and 17%, respectively. Different carbon sources did not significantly influence the decolorization. The distaining activity was proved to be a laccase related to the mycelium because in the presence of sodium azide, the distaining activity of mycelium was completely inhibited, supernatant did not present activity as well. These results show a great potential of the isolate to be applied in an environmental-friendly alternative for textile dye treatments. The enzyme localization could represent higher stability and advantages in industrial scale, dispensing the immobilization processes.