The biological decolorization methodology and the mechanism involved in the degradation of Acid Red 66 was chosen as a model of azo dye using the white rot fungi Trametes versicolor was studied. Biodecolorization of Acid Red 66 using white rot fungi T versicolor was demonstrated by the decolorization of the culture medium, the extent of which was determined by monitoring the decrease in absorbance at 506 nm. The biodecolorization kinetics of Acid Red 66 (100 ppm) was found to be first order and the degradation rate coefficient is 1.312 x 10(-2) min(-1) (R = 0.96683, n = 8) at 30 degrees C. The effects of independent variables such as carbon sources, nitrogen sources pH, and temperature on the biodecolorization of Acid Red 66 was also investigated. (C) 2009 Elsevier B.V. All rights reserved.