Crude proteolytic enzyme from Bacillus halodurans BCRC 910501 and its application in leather processing

Enzymes are biological catalysts that exist in all living organisms. Proteases are one of the most important enzymes in the industry; microbial proteases are widely used in the food, textile, detergent, and leather industries. Traditionally, alkaline proteases are used in the leather industry for bating, however, due to environmental issues, there are many investigations for the application of proteolytic enzymes in other operations such as soaking, unhairing, and derma opening up. This study aimed to produce a proteolytic enzyme from B. halodurans BCRC 910501 and apply it to the soaking of salted hide. After cultivation, the crude enzyme was used for further analysis and leather processing. The results showed an enzyme with higher caseinolytic activity compared to keratinolytic activity. A soaking study found that enzyme improves rehydration, non-collagenous protein, and salt removal. Enzymatic soaking affected collagenous proteins more than the control, but did not significantly impact wet-blue leather properties. Using this enzyme in leather processing might be suitable to reduce the duration of soaking and the number of process steps.