Enzymatic desizing of cotton fabric using a Ca2+-independent α-amylase with acidic pH profile

This study aims to optimize the enzymatic desizing of cotton fabric using a metal and Ca2+ ion-independent α-amylase from Bacillus sp. KR-8104 that is highly active under acidic conditions. The optimum desizing in terms of weight loss% and Tegewa violet scale was obtained at 60 °C, pH 5–6 for 30 min in the presence of 4.5 IU of α-amylase. Enzymatic and acid desizing was carried out in the presence of this enzyme simultaneously. Furthermore, enzymatic desizing and demineralization steps can be combined in a single process at lower pHs. The experiments showed that enzymatic desizing could be carried out in a wide range of temperatures between 30 °C and 70 °C. Chloride salts of Ba2+ at 5 and 10 mM and K+ at 10 mM increased enzyme activity and desizing efficiency. Since the desizing yield is not influenced by EDTA, it could be used in the desizing bath to remove most undesirable metallic ion contaminants causing hardness. Overall, our data showed that this α-amylase would improve desizing and its subsequent processes, and result in conservation of time, energy and chemicals.