Decolorization of azo dyes by <i>Pycnoporus sanguineus</i> and <i>Trametes membranacea</i>

Abstract

In the present work, decolorization of dyes Orange II and Black V by the fungi Pycnoporus sanguineus and Trametes membranacea was assessed at six, 12 and 18 days, through fractional design, with a total of 16 trials, statistically represented by 2^6-2. The fungi were grown in Erlenmeyer flasks containing the malt and King media supplemented with 0.05% m/v of the dyes Orange II and Black V, respectively under pH 4.5 and 5.0 in the presence or absence of agitation and/or luminosity. The fungal species showed different behaviors on the biomass production and decolorization of the dyes under different growing conditions. P. sanguineus showed the highest production of biomass (7.5 g/l) when grown on King medium supplemented with dye Black V, under the absence or presence of agitation, luminosity and at pH 4.5 and 5.0, while T. membranacea showed a 7.5 g/l of biomass in all growing conditions for the two dyes tested. As for the agitation of the flasks, the rotation speed of 130 rpm was the best condition for color removal. The fungi studied reached a decolorization percentage of over 50% for the dyes in all flasks under agitation.

Keywords: Basidiomycetes, white rot fungi, azo dyes, decolorizations