Characteristics of collagen from the skin of clown featherback (Chitala ornata)

Acid soluble collagen (ASC) and pepsin soluble collagen (PSC) from the skin of clown featherback (Chitala ornata) were isolated and characterised. Yields of ASC and PSC were 27.64 and 44.63% (dry weight basis) with total collagen recovery of 82.08%. Both collagens contained glycine as the major amino acid with relatively high content of proline, hydroxyproline and glutamic acid/glutamine. Nevertheless, they had the low content of cysteine, histidine and tryrosine. The collagen was characterised as type I, comprising (1)(2)2-heterotrimer. Pepsin-aided process did not affect triple-helical structure of PSC as determined by FTIR spectra. Thermal transition temperature of ASC (36.28 degrees C) was slightly higher than that of PSC (35.23 degrees C). However, no differences in isoelectric point (5.54-5.68) between ASC and PSC were observed. Therefore, collagen from the skin of clown featherback could be successfully extracted for further applications.