Abstract:

Collagen was prepared from channel catfish skin by the steps of swelling in acetic acid, beating with blender, dissolving in diluted acetic acid, and neutralizing with sodium hydroxide solution (the final precipitate is collagen). In the present study, the conditions for swelling channel catfish skin in acetic acid were explored emphatically. The results showed that when channel catfish skin was swelled in 0.5 mol/L acetic acid for 6 h, the extraction yield of reached maximum, 92%. Subsequently, the obtained collagen was desalted by water-washing method, and then the impurity proteins in it were removed by neutral protease or alkaline protease. SDS-PAGE analysis indicated that no cleavage happed on α-chain of collagen during extraction and purification. Data from CD and X-ray showed that this purified collagen remained its structural integrity as triple-helix.

Key words: channel catfish skin, collagen, extraction, enzyme, desalination