Hanifatul Azizah, Suharti Suharti
Chicken feathers are waste containing 82% protein in the form of keratin that enzymatically can be degraded by a class of protease called keratinase. Bacillus sp. MD24 and Salinivibrio proteolyticus DV TG6, were both able to degrade chicken feathers at 37°C, and pH 8. This condition offer possibility to combine both organisms as a consortium to work synergistically in degrading chicken feathers. This paper reports our work on the production of keratinase by Bacillus sp. MD24 and Salinivibrio proteolyticus DV TG6 consortium. This paper also reports our work on improving keratinase by the consortium through the addition of metal ions and additional carbon sources. The keratinase production was performed by submerged fermentation and Co2+; Ni3+; Mn2+; Ca2+; Zn2+; Cu2+; and Fe2+ were tested as metal ions supplement during fermentation. Various additional carbon sources were tested including glucose, corn flour, coconut pulp, and corn cobs. The result showed that keratinase production by the consortium was slightly increased compared to its member alone. Interestingly, although Mn2+; Ca2+; Zn2+; Cu2+; and Fe2+ ions improved keratinase production by Salinivibrio proteolyticus DV TG6 it suppressed keratinase production by Bacillus sp. MD24 and none of those metal ions improved keratinase production by the consortium. However, Mn2+ did not suppress the enzyme production. Coconut pulp shortened keratinase production by Salinivibrio proteolyticus DV TG6 but not for Bacillus sp. MD24 and the consortium. Overall, it concluded that the consortium did not work well. The keratinase production by Salinivibrio proteolyticus DV TG6 alone was improved by adding some metal ions and coconut pulp; however, its activity was relatively low compared to the production by Bacillus sp. MD24 and the consortium. Salinivibrio proteolyticus DV TG6 originated from a salt pond and it might be better to produce keratinase under higher salt concentrations. © 2024 Author(s).
Department of Chemistry, Faculty of Mathematics and Natural Sciences, State University of Malang, Jl. Semarang 5, Jawa Timur, Malang, Indonesia