Optimization of keratinase production by Bacillus SLII-I bacteria in chicken feather waste medium

Maharani Pertiwi Koentjoro, Endry Nugroho Prasetyo*, Ahmad Marzuki Rahmatullah

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

2 Citations (Scopus)


Keratin is an undissolved protein in water and difficult to transform by proteolytic enzymes because there is a cystine disulphide bond. One of the bacteria that produce keratinase enzyme is Bacillus sp. which is able to break the disulfide bond on the keratin protein into a soluble protein. The purpose of this research is to produce keratinase optimally through analysis of bacterial growth profile, protein content, and keratinase activity by varying pH conditions and composition of chicken feather waste medium. The optimization of keratinase was based on the growth curve of bacteria cultured on 3 medium types namely Nutrien broth, minimal medium feather meal, minimal medium feather meal pepton 1% and 3 types of pH 7, 8, and 9, for keratinase activity from crude enzyme extract, While for protein profile analysis using ammonium sulphate method, isoelectric point, and SDS-PAGE was done to find out protein profile. From the result of optimum keratinase production from minimal medium feather meal pH 7, the highest keratinase enzyme activity was 0.34 unit / ml. The isoelectric point of the keratinase enzyme is known at pH 5.3 while the molecular weight based on the SDS-PAGE yield is 38kDa.

Original languageEnglish
Pages (from-to)482-488
Number of pages7
JournalARPN Journal of Engineering and Applied Sciences
Issue number2
Publication statusPublished - 1 Jan 2018


  • Bacillus sp.
  • Keratin
  • Keratinase optimization
  • Protein profile


Dive into the research topics of 'Optimization of keratinase production by Bacillus SLII-I bacteria in chicken feather waste medium'. Together they form a unique fingerprint.

Cite this