Production of laccase from a white rot fungi isolated from the Amazon forest for oxidation of Remazol Brilliant Blue-R

Abstract

The purpose of this study was to investigate the production of laccase from a white rot fungi isolated from the Amazon forest for oxidation of Remazol Brilliant Blue-R (RBB-R). Initially, a small screening was carried out aiming to find laccase producers. The next step was to investigate, using factorial design and Response Surface Methodology (RSM), the influence of the content of glucose, peptone and CuSO 4 in the production of laccase by the selected fungi. Subsequently, the ability of the produced laccases to oxidize RBB-R was investigated. As a result, Agaricomycete (UFAM1) presented the highest laccase production (117.2 U/L) in the screening assay. Using the factorial design and surface responses was possible to determine the best conditions for laccase production by Agaricomycete (UFAM1). Then, the excellent medium to produce laccase was composed of glucose-20 g/L, peptone-10 g/L and CuSO 4 -500 µM. However, in the RBBR decolourization assays, the filtered of the culture promoted a decolourization activity of 2 U/L. This is the first research that demonstrates a fungal strain from the Amazon forest able to produce high levels of laccase, without demonstrating metabolic repression to high contents of carbon and nitrogen sources and that the produced laccases are able to cause oxidative degradation of RBB-R, an important model of recalcitrant compound.