Biotechnological Aspects and Perspective of Microbial Keratinase Production

Figure 3

Plate clearance assay for proteolytic activity. Secretion of proteolytic enzymes by Aspergillus species, Mucor species, and Mycelia sterilia is shown as example. The 8% gelatin agar plates were prepared and a pinpoint inoculum was spotted at the center. The clear zone around the colonies indicated the presence of proteolytic activity, which was due to the complete degradation of gelatin. Aqueous saturated solution of ammonium sulfate was added on the surface of the agar for clear visualization.