Characterization of detergent stable and feather degrading serine proteases from Bacillus mojavensis A21

The present study describes the characterization of crude protease from Bacillus mojavensis A21 and its evaluation in detergent and chicken feathers hydrolysis. The strain was found to produce at least six major extracellular proteases as shown by casein-zymography. The optimum pH and temperature for proteolytic activity were 8.0-11.0 and 60 degrees C, respectively. The crude protease showed extreme stability towards non-ionic (5% Tween 80 and 5% Triton X-100) and anionic (1% SDS) surfactants, and relative stability towards oxidizing agents. Additionally, it showed excellent stability and compatibility with various solid (7 mg/ml) and liquid (1%; v/v) detergents at temperatures from 30 to 50 C. In the presence of solid detergents, the enzyme preparation retained 100% of its initial activity after pre-incubation for 1 h at 40 C with Axion and Ariel, followed by Nadhif (87%), Dixan (85%) and New Det (82%). With liquid detergents, the enzyme preparation retained 100% of its original activity after pre-incubation for 1 h at 40 degrees C with Dixan and Nadhif. Wash performance analysis revealed that A21 crude protease could effectively remove blood-stains. In addition, B. mojavensis A21 proteolytic preparation showed important feather degrading activity. Considering its promising properties, B. mojavensis A21 enzymatic preparation may be considered a potential candidate for future use in biotechnological processes, particularly in detergent and in the processing of poultry waste. (C) 2010 Elsevier B.V. All rights reserved.