Characterizing hydrolysate from duck feather degradation by Pseudomonas sp. PK4, Bacillus cereus TD5B, and Bacillus cereus LS2B

Duck feathers are mainly composed of keratin, which is difficult to degrade. We want to know the ability of indigenous strains to produce keratinase and the ability to degrade duck feather's keratin and observe the hydrolysate's amino acid profile. All the strains were confirmed to produce keratinase from the formation of clear zones on an agar medium., Bacillus cereus LS2B, Bacillus cereus TD5B, and Pseudomonas sp. PK4 had the maximum enzyme activity on the casein substrate with 10.52 U/mL, 6.24 U/mL, and 16.42 U/mL, respectively. In addition, Strains LS2B, TD5B, and PK4 have activity of 5.23 U/mL, 7.01 U/mL, and 11.3 U/mL, respectively, while growing on the keratin substrate. Pseudomonas sp. PK4, Bacillus cereus LS2B, and Bacillus cereus TD5B degraded 38%, 38%, and 19% of the substrate, respectively. We found 12 amino acids during HPLC analysis. This study concludes that strains Strain PK4, LS2B, and TD5B can produce keratinase and can degrade the keratin of the duck feather substrate into amino acids.