Keratin cannot be degraded solely by common proteolytic enzymes such as pepsin,
trypsin, and papain. Keratinases have been produced up to a significant level by some
microorganisms [7] including bacilli [8–10], fungi [11–13], and actinomycetes [14, 15]. The
ability of microbes to degrade keratin and the level of keratinase production vary according
to species, type of substrates, and, also, culture conditions [16].