Comparison of acid-soluble collagen characteristic from three important freshwater fish skins in Mekong Delta Region, Vietnam.

The utilization of three important freshwater fish skins including tra catfish (Pangasianodon hypophthalmus), clown knifefish (Chitala ornata), and tilapia (Oreochromis niloticus) in Mekong Delta Region, Vietnam for acid-soluble collagen (ASC) extraction was investigated. From the SDS-PAGE profile, ASCs can be identified as type I collagen (consisting of two different α- chains and β component in protein pattern).The solubility among individual collagens was highest at pH 1-2, depending on fish species. FTIR spectra showed a close relationship between the lowest wavelength number in amide I and amide III regions and the stabilization of the triple-helical structure in ASC from clown knifefish. ASC from clown knifefish skin had highest ASC yield and contained highest amino acid content as well as the highest denaturation temperature (33.09°C) in comparison with ASCs from tra catfish and tilapia skin. PRACTICAL APPLICATIONS: Acid-soluble collagen (ASC) from three important fish skins in the Mekong Delta Region, Vietnam was characterized. ASC from clown knifefish skin showed the highest of extraction yield and denaturation temperature. The thermal stability of ASC from clown knifefish skin not only related to the content of imino acid but is also had the correlation with the transition of α-helix in amide I and III.