Enzymatic Dehairing of Goat Skin Using Keratinase from Bacillus sp . MD24, A Newly Isolated Soil Bacterium

摘要

A newly keratin-degrading bacterium was isolated from a residential soil at Wajak district, Malang, East Java, Indonesia. Sequence homology analysis showed the 16S rRNA had only 89% sequence identity to the available bacterial 16S rRNA which led to a discovery of a new species of Bacillus. The bacterium was named Bacillus sp MD24. The isolated bacterium degraded 71% mass of whole chicken feathers within 10 days. Keratinase fermentation using 1% of chicken feathers as sole source of carbon and nitrogen exhibited highest enzyme activity at third day under optimum condition (pH of 8 and temperature of 37o C). At enzyme concentration of 0.3 U/mL, the crude extract keratinase started to exhibit dehairing activity on goat skin after an overnight incubation; the best incubation was achieved at 72 hours. Surface of enzymatically dehaired goat skin was compared to chemically dehaired skin goat. The result showed similar or improved surface of the skin which makes the crude keratinase from Bacillus sp MD24 a potential candidate for application in leather industry to avoid pollution problems due to the use of chemicals.