Treatment of protein fibres with enzyme

Enzymatic pre-treatments to protein fibres are generally concentrated on wool and silk. It is possible to remove skin residues, skin grease and vegetable matter ol wool by enzymatic degradation method. Furthermore, the wool surface can be modified, and felt free finishing with simultaneous improvement of lustre and handle of woollen fabric is possible by enzyme treatment. 

The two major morphological parts in the structure of wool are cuticle and cortex. The epi-cuticle of wool fibres surrounds each cuticle, it consists of approximately one-quarter fatty acid and three-quarters protein by mass. The hydrophobic epiCLiticle acts as a barrier to dyes which enter the wool fibre between cuticle cells through the highly cross-linked cell membrane complex (CMC). Enzyme from the liquor can diffuse into the interior of the fibre and hydrolyse parts of the endocuticle and proteins in the cell membrane complex, completely damaging the fibre if not controlled. In contrast, the catalytic action of enzyme on cotton is confined to the surface and the amorphous region only. 

Enzymes such as proteases, lipases, lipoprotein lipases and proteolytic enzyme derived from the bacterium Streptomyces fradie (known as SEP) is capable of attacking natural keratin hydrolysing some peptide linkages. However, proteases arc-most widely used. 

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