An alkaline and thermostable pectinase production from Bacillus subtilis SS was optimized under submerged fermentation and its application was tested in textile industry for desizing and bioscouring of cotton and micropoly fabrics. Desizing of fabric was the best with 5 U/g pectinase treatment for 120 min at pH 9.5 and 65 C. Under optimized conditions of bioscouring, desized cotton showed highest reducing sugar liberation and weight loss than desized micropoly. Along with enzyme, addition of chelating (EDTA) and wetting agent markedly enhanced the weight loss compared to single use of enzyme or EDTA alone. Agitation (50 +/- 2) enhanced the weight loss values of cotton (1.9%) and micropoly fabric (1.7%) at pH 9.5 after treatment time of 2h. Bioscouring of fabrics with pectinase resulted in enhancement of various physical properties of fabrics viz. whiteness (1.2%), tensile strength (1.6%) and tearness (3.0%) over conventionally alkaline scoured fabrics. (C) 2009 Elseiver Ltd. All rights reserved.