Figure 5: Proteolytic (a) and keratinolytic (b) activity as a result of cultivating Bacillus sp. C4 on basal medium II (empty marks) and on modified basal medium II (filled marks), supplemented with chicken feather (diamond shape) and sheep wool (square shape), 10 g/l each. (c) Illustrates the levels of soluble proteins produced under the same conditions.