PRODUCTION AND PARTIAL OPTIMIZATION OF MICROBIAL KERATINASE ENZYME BY Bacillus tropicus, KS3 NOVEL ISOLATE FROM POULTRY WASTE SOIL SAMPLES

Feather waste is generated abundantly but rich in natural protein which largely contributes to environmental pollution. The present study reports potent feather-degrading bacteria isolated from poultry waste-contaminated soil. A novel isolated bacterium was identified as Bacillus tropicus (Accession Number MT075474; Strain Number KS3). The medium components and culture conditions were optimized to enhance keratinase production through shake flask culture by one factor at a time (OFAT). In chicken feather meal (5 g/l) media highest keratinase production was shown when pomegranate peel powder (5 g/l) was used as a carbon source and peptone (5 g/l) as a nitrogen source. Pomegranate peel powder is very, low cost, and easily available. After optimization, the maximum yield of keratinase was found at 24 h of incubation and at 37 °C with pH of 6.5 and inoculums volume 4.5% under 150 rpm when chicken feather, peptone, and pomegranate peel powder were used as nutrient sources. This study reveals that higher keratinase production under OFAT conditions is 107.06 U/ml that shows 3.0-fold increased when all optimized parameters were applied simultaneously. Therefore, Bacillus tropicus KS3 is used for large-scale production of keratinase for industrial purposes in less time.