Biodegradation of textile dye effluents by Trametes versicolor

Biodegradation of textile dye effluents by Trametes versicolor
The textile industry plays an indispensable role in our day-to-day life while their dye effluents also report a major issue with their contents like grease, dirt, residual dyes and metals, such as Cr, As, Cu, Zn, etc. which are primarily released into soil, water, etc. resulting in pollution and ill effects to both human beings and animals. Certain higher groups of fungi, such as wood rot fungi are widely reported for their capability of degrading these dyestuffs along with its constituents such as lignin. The efficiency of white rot fungi is attributed to its production of extracellular enzymes, such as lignin peroxidase (LiP), manganese dependent peroxidase (MnP), laccase and versatile peroxidase, which are collectively called as lignolytic enzymes. Whereas, LiP, MnP and laccase serve as the predominant enzymes. LiP is an oxidative enzyme with highest redox potential which is the only enzyme capable of degrading non-phenolic lignin which is about 80-90% of total lignin while phenolic lignin constitutes only 10-20% of the total lignin. White rot fungi were found to produce only laccase and/or MnP and others produce LiP in addition to laccase and/or MnP.

Trametes versicolor, a white rot fungus is found to efficiently degrade lignin. It produces only laccase and MnP but not LiP, instead, it degrades lignin by having a high redox potential mechanism; whereby, converting non-phenolic lignin units into phenolic ones which are then further oxidised by MnP/laccase. Trametes versicolor secretes certain low molecular weight compounds, such as organic acids, fatty acids, glycopeptides and Fe3+-chelating compounds. These Fe3+ chelating compounds reduce Fe3+ to Fe2+ and hydrogen peroxide by producing OH radical which are then further oxidised by MnP/laccase. Currently, Trametes versicolor is used extensively in decolourising craft mill effluents. While it is found to degrade carpet dye effluent with an efficiency of 95% within 10 hours of incubation although the effluent did not support the growth of the organism. It is the major organism used for waste water decolourisation extensively in Brazil and Spain.


How to cite this article:
Kiruthiga M. Biodegradation of textile dye effluents by Trametes versicolor. BioLim O-Media. 22 June, 2016. 4(6).
Available from: http://www.biolim.com/read/BOMA0124.