Characterisation of acid-soluble collagen from skin and bone of bigeye snapper (Priacanthus tayenus)

The compositions and some properties of acid-soluble collagens (ASC) of the skin and bone of bigeye snapper, (Priacanthus tayenus) were investigated. The collagens were extracted with the yields of 10.94% and 1.59% on the basis of wet weight, from skin and bone, respectively. Similar electrophoretic patterns of collagens from the skin and bone were observed. Both collagens comprised two different α chains, α1 and α2 and were classified as type I collagen. However, peptide maps of collagen from the skin and bone of bigeye snapper, digested by V8 protease and lysyl endopeptidase, revealed differences between collagens from skin and bone, and both were completely different from those of calf skin collagen. Collagen rehydrated in acetic acid had lower Tmax and enthalpy than those rehydrated in deionised water, suggesting a conformational change caused by acid. Collagens form the skin and bone had the highest solubility at pH 2 and 5, respectively. No changes in solubility were observed in the presence of NaCl up to 3% (w/v). However, a sharp decrease in solubility was found with NaCl above 3% (w/v).