DYE DECOLORIZATION AND BIOMASS DEGRADATION BY Pleurotus pulmonarius AND Pleurotus ostreatus

Uncontrolled release of dyes and coloring materials as industrial effluents is one of the primary causes of environmental pollution. The present work was conducted to evaluate two fungal strains, Pleurotus pulmonarius and Pleurotus ostreatus in terms of their biodegradation ability of different dyes. The influence of pH on laccase activity and dye adsorption, phenol oxidase activity, ecotoxicity, and biomass degradation ability of cigarette butts (filters) was also included. In case of Pleurotus pulmonarius, the highest dye degradation activities was observed in methylene blue, while Pleurotus ostreatus showed the highest dye degradation activity in crystal violet. Percent dye degradation activity was significantly higher in Pleurotus pulmonarius than Pleurotus ostreatus (in case of methylene blue and crystal violet). It was seen for both the strains pH 5-7 was an optimum showing maximum dye adsorption (in case of methylene blue and crystal violet) and laccase activity. At higher pH values, the adsorption ability decreases. But both strains decolorized basic fuchsin at high pH (pH 7-9) only. Both the fungal strains were found to have extracellular phenol oxidase activity. The present study showed that after the bioremediation the dye solution had insignificant ecotoxicity. Biomass of cigarette filters was significantly reduced with Pleurotus pulmonarius while in case of Pleurotus ostreatus, the effect was less significant.