In order to isolate keratinase producing bacteria, the enrichment process using
some natural sources including chicken feather, soil, compost and poultry waste
digester was carried out. Screening program was conducted at two steps at 30 and
55°C uSing mil~ 'agar plates to .detect the proteolytic potency of obtained isolates. The
third step of screeninq programme was carried out using a liquid cultivation medium
. containing feather as source for nitrogen and carbon source measuring both total
soluble protein and free amino acids as indicators for keratinase production at 37°C . . The identiflcatlon tests were also . followed· for the selected. isolates. Different cuttivation media were also used for. bacterial growth and keratinase production. Obtained results showed that sporeforminq bacteria represent 51.7% of the total .. obtained isolates and' about 36.4% of the totat bacterial isolates of chicken feather. Data showed also that two isolates of spore forming bacteria which were most acnve . in keratinase -production -are belonging to the genus Bacillus. Following the protocol of the Bergy's Manual of Systematic Bacteriology, the two isolates showed to be .
closely related to B. licnenitotmis. To sefect the most keratinase productive cultivation.
medium among est five media used,. the values of kerafinase activity, total soluble.
protein, and free amino acldsobtained from each medium were also considered.