Figure 4

(A) Functional group characterization and structural changes in intact (blue) and hydrolyzed feather samples at 48 h (black) and 96 h (red) using ATR-FTIR spectra. (B) Chemical fingerprinting of hydrolyzed and unhydrolyzed chicken feathers using Raman spectra of intact feather (blue) and hydrolyzed feathers at 48 h (black) and 96 h (red) incubation.