10.22376/ijpbs.2019.10.1.p1-12 Volume 4 Issue 3 2013 (July - September) Bismarck Brown Y was selected as model textile dye. The fungal strain lessThan i greaterThan Alternaria brassicae lessThan /i greaterThan TSF – 07 isolated from textile wastewater sludge was screened for decolourization of Bismarck Brown Y. Optimization was carried out with respect to carbon source, nitrogen source, pH, inoculums size, incubation period and temperature. It was found that the optimum inoculum size, pH and temperature were 2.5%, 5.0 and 35 lessThan sup greaterThan 0 lessThan /sup greaterThan C respectively. Fructose at 1.0 % and yeast extract at the concentration of 0.1 % was found to give maximum decolourization. Further, it was found that the culture has brought about almost 96.03% decolourization of a recalcitrant dye, Bismarck Brown Y (100 mgL lessThan sup greaterThan -1 lessThan /sup greaterThan ) at shaking condition within 3 days. This isolate also showed the degradation as evidenced from the reduction in the term of COD mg/L to the extent of 68.09 % within three days. The biodegradation was monitored by UV–Vis and FTIR spectroscopy.This study revealed the enormous biodegradation abilities of indigenous microbial flora. KANYAKUMARI P. SHINDE AND P. R. THORAT Mycoremediation, Alternaria brassicae, optimization, biodecolourization, FTIR, COD. 862-873