Keratinolytic potential of stains isolated from feather – dumping site

Abstract

Keratin is insoluble macromolecule, comprised of long polypeptide chains that are mainly found in hair, wool, nail, horns and feathers which its stability depends on the adjacent chains linked by disulphide bonds. Several bacteria, fungi and actinomycetes are microorganisms which associate to the secretion of keratinolytic enyzmes called keratinases that play a significant role in the degradation of keratin. For the present study, keratinolytic microorganisms were isolated by keratin baiting technique using feathers and hair as baits. The keratinase enzyme producing microorganism was screened out from soils in different places such as poultry farm, mosque, school and park. Among all places, Aspergillus niger showed the highest numbers of colonies in all places and were selected for screening. Keratinase enzyme produced by A. niger was optimized in different pH concentration of 5, 7 and 9. Moreover, it was also optimized under different temperatures of 25 °C, 37 °C and 45 °C. Standard curve was prepared to estimate the content of crude enzyme protein using Bovine serum albumin (BSA) as standard. Lastly, the keratinase enzyme was evaluated by immersing feather and hair in the protein solution.