|dc.description.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.||en_US