Evaluation of individual fungal species and their co-culture for degrading a binary mixture of dyes under solid-state fermentation

Abstract

Description of the subject. In recent years, biological methodologies, such as solid-state fermentation, have acquired a great relevance for bioremediation of complex molecules because of their efficiency and low environmental impact. Specifically, the use of white-rot fungi in different biotechnological processes has emerged as a promising strategy given their broad enzymatic potential. Objectives. Evaluation of three individual fungal species, as well as various fungal consortia of these species, for the degradation of a mixture of dyes, brilliant blue -allura red, through solid-state fermentation. Method. The species Pleurotus pulmonarius, Pleurotus ostreatus and Trametes versicolor were assessed, both individually, and in their binary consortia. The interaction between the mycelia of the different white-rot fungi was taken into account as a criterion for using their consortia to degrade the mixture of pollutants under solid conditions. The dyes were adsorbed onto the agro-industrial by-products flower stems and corncob. The fermentative process was carried out over 20 days, after which the degradation percentage was quantified by UV-Vis spectroscopy.Results. The highest degradation percentage was obtained after fermentation by T. versicolor alone. This species reached an average degradation of 79.57% of the binary mixture of dyes, brilliant blue -allura red. Meanwhile, the best consortium, composed of P. ostreatus and T. versicolor, achieved a degradation of 63.24%. Conclusions. These results suggest that the use of fungal consortia, in solid media, does not always lead to a synergy between species for improved dye degradation by the integrated strategy that includes the processes of adsorption and solid-state fermentation. Instead, competition for space and nutrients associated with growth on a solid substrate could decrease the degradation efficiency.

Biodecolorization and biotransformation of methylene blue using mixed cultures of brown-rot fungus Daedalea dickinsii and filamentous fungus Aspergillus oryzae: identification of metabolites and degradation pathway

“…According to Correa et al , using fungal consortia can result in greater substrate colonization, enhanced synthesis of pertinent enzymes, and improved resistance to contamination by other organisms, making their use potentially more efficient. 21 For instance, Kuhar et al reported Ganoderma lucidum – Trametes versicolor consortium exhibited a higher rate of malachite green degradation when compared to other conditions. 22 While El-Rahim et al also revealed that a fungal consortium was able to achieve up to 100% degradation efficiency for a number of different types of azo dyes.…”