Morphological Studies on Assembling Behavior of Oligopeptides Obtained by Dissolution of Feather Keratin with Alkali

The self-assembling behavior for the oligopeptides obtained from the dissolution of feather keratins via the alkaline hydrolysis process was investigated. The entities generated from the aqueous solution of oligopeptides showed a dendrite-like and non-birefringent structure. To enhance the molecular orientation for the oligopeptides in the assembling process, the electrospinning was applied. The as-spun fibers showed birefringent structure. However, no crystal diffraction was recognized in the selected-area electron diffraction analysis. To modify the crystallizing property of the oligopeptides, the superheated water treatment was conducted and the cystine and/or cysteine residues were completely destroyed. Then the entities from the aqueous solution of the treated oligopeptides became crystalline. However the crystal growth stopped up to its diameter of ∼40 μm.