Decolorization of reactive dyes by the white rot fungus Trametes versicolor in sequencing batch reactors

Abstract

The white rot fungus Trametes versicolor was shown to be capable of decolorizing three reactive dyes in a sequencing batch process, using glucose as the carbon and energy source over an extended period without supplementation of new mycelium. Decolorization activity was related to the expression of extracellular peroxidases and could be continuously reactivated by sheering the suspended pellets. Pure culture experiments were carried out simultaneously in agitated Erlenmeyer flasks and in completely stirred tank reactors with two azo dyes, C.I. Reactive Black 5 and C.I. Reactive Red 198 as well as the anthraquinone dye C.I. Reactive Blue 19 (Brilliant Blue R). Results show high and stable degrees of decolorization of 91%-99% in both systems, which could be repeated without decrease in activity over time. Under nonsterile conditions only five cycles of decolorization could be achieved. An increasing bacterial population suppressed fungal growth and the formation of peroxidases.

Integrated fungal biomass and activated sludge treatment for textile wastewaters bioremediation

“…During W1 treatment, the nine fungal strains showed in general a good adaptation to the wastewater. A very important aspect to consider is the fact that generally the metabolic capacity of fungi decreases in the absence of sterile conditions, as demonstrated by Borchert and Libra (2001). In our case, the fungal strains remained active even in the presence of the microflora associated with the real dyeing wastewater.…”

Effects of glucose on the decolorization of Reactive Black 5 by yeast isolates

“…Numerous studies were focused on the biological treatment due to the potentially low cost (Borchert and Judy, 2001). Decolorization of various dyes using white rot fungi or their ligninolytic enzymes was widely studied in the past years and several bioreactors in lab-scale were proposed for this purpose (Borchert and Judy, 2001).…”

“…Numerous studies were focused on the biological treatment due to the potentially low cost (Borchert and Judy, 2001). Decolorization of various dyes using white rot fungi or their ligninolytic enzymes was widely studied in the past years and several bioreactors in lab-scale were proposed for this purpose (Borchert and Judy, 2001). However, the rigorous conditions for enzyme production in dye containing wastewater and the risk of contamination by bacteria under non-sterile conditions retard the application of white rot fungi for wastewater treatment (Borchert and Judy, 2001).…”

“…Decolorization of various dyes using white rot fungi or their ligninolytic enzymes was widely studied in the past years and several bioreactors in lab-scale were proposed for this purpose (Borchert and Judy, 2001). However, the rigorous conditions for enzyme production in dye containing wastewater and the risk of contamination by bacteria under non-sterile conditions retard the application of white rot fungi for wastewater treatment (Borchert and Judy, 2001). On the other hand, yeast, another kind of fungi, has been successfully applied to treat industrial effluents such as food-, molasses-, and oil manufacturing wastewater as reported by Japanese scientists (Chigusa et al, 1996;Moriya et al, 1990;Yoshizawa et al, 1981) Although several yeasts were reported to be able to remove dyes through the mechanism of biosorption (Kakuta et al, 1992;Martins et al, 1999;Meehan et al, 2000), reports on decolorization by yeast through the above ligninolytic system have been minimal (Hofrichter, 2002).…”

Fungal Decolourization and Degradation of Synthetic Dyes Some Chemical Engineering Aspects

“…One cycle lasted for 5-20 days. 91-99% of colour removal was achieved in the experiments which lasted up to 200 days (Borchert & Libra, 2001). Various strategies for the decolourization of Reactive Black 5 with Trametes versicolour in a 4-L aerated stirred tank reactor with two flat-blade impellers under non-sterile conditions were compared.…”