Biological liquefaction and dehairing of tannery hides using protease crude extract from Bacillus safensis

Abstract

Background: The contemporary usage of leather products has established large number of tanneries worldwide and increased the production of leather goods, releasing huge solid and liquid tannery waste. The amount of firm waste from the unprocessed skins and hides generated from tannery is increased day by day posing a solemn threat to the health and environment. It was reported to account 5-7% of the total solid wastes. This study aims for the biological approach of utilizing tannery hide waste for the production of bacterial enzymes. Proteases produced by the microbes have multiple commercial and industrial applications. Methods: The physiochemical property of raw trimming of bovine tannery hides was analyzed for the segregation of protease constructing bacteria. Seven bacterial isolates from the raw trimming bovine tannery hides were isolated and screened for their protease production and activity. The isolated bacterial strains were documented through morphological, biochemical tests and confirmed by MALDI-TOF and 16S rRNA sequencing as Bacillus safensis. Results: Among the seven isolates, Bacillus safensis established better proteolytic action. The culture conditions and media requirements were optimized for the maximum growth of the chosen bacteria. The crude proteolytic enzyme from Bacillus safensis was extracted, analyzed for its application in tannery hide dehairing activity through microbial fermentation. Further, the antibacterial and antioxidant properties displayed by the protease crude extract from Bacillus safensis could be explored for potential industrial and pharmaceutical applications. Conclusion: The verdict of the present study reveals a novel source of protease enzyme with the superior dehairing activity. Further, the research shed light on the strategies to reduce environmental pollution by the conversion of tannery waste into economically important products.