In this study, the production of a-amylase using a pure culture of Bacillus sp. KR-8104, a locally isolated strain, was optimized and tested for the simultaneous desizing of cotton fabric. Optimum production was obtained at 45 degrees C, pH 5.0-6.0 in two media: one contained soya powder and chicken excrement and the second contained meat powder and chicken excrement; these media provided novel nitrogen sources. Optimum desizing was obtained at 40-45 degrees C, pH 5.0-6.0, 10 h pi (TEGEWA scale 6) and 22-24 h pi (TEGEWA scale 9). This alternative process is very attractive for the textile industries and facilitates an economical technology with low resource consumption and emission. Due to the application of different and very inexpensive raw materials and to the simultaneous enzyme production and desizing, which may be referred to as fermentative desizing, the economic perspective of this method is promising. (C) 2014 Elsevier Ltd. All rights reserved.