Optimized production of extracellular proteases by Bacillus subtilis from degraded abattoir waste



Proteases are ubiquitous in occurrence and are found in all living organisms. These are essential for cell growth and differentiation. The extracellular proteases are of a high commercial value and find multiple applications in various industrial sectors. The present study describes the screening of protease producing bacteria from a hitherto unexplored source i.e. degraded waste from abattoir. Three isolates were found namely yellow, white and orange coloured bacteria. Amongst them, white colored colony was found to be more suitable for protease production. The morphological, cultural, biochemical and 16S rRNA confirmed that the isolate was Bacillus subtilis. Physical and chemical parameters were optimized for maximum protease production and optimum temperature and pH was found to be 40oC at pH 14. Glucose as a carbon source and yeast extract as a nitrogen source further stimulated the production process giving maximum protease activity to be 20.74 U/ml and 20.67 U/ml. The applications of protease in detergent and solvent industry were tested and it was revealed that the purified enzyme can be used as an additive in detergent industry.

Key words: Bacillus subtilis, protease, textiles, abattoir waste, enzyme activity, optimization, detergent industry

Volume 5, Number 1 (2016) pp. 29-36   [ Full Text (PDF) ]