Characteristics of Collagen from Parrotfish (Chlorurus Sordidus), Tiger Grouper (Epinephelus Fuscoguttatus) and Pink Ear Emperor (Lethrinus Lentjan): Effect of Acetic Acid Concentration and Extraction Time

The use of marine fish's skin waste such as parrotfish (Chlorurus sordidus), tiger grouper (Epinephelus fuscoguttatus), and pink ear emperor (Lethrinus lentjan) needs improvement to increase its economic value and sustainability. Therefore, this study aims to investigate the effect of fish skin to acetic acid ratio with different extraction times on the yield and characteristics of skin collagen obtained from three-marine fishes (parrotfish, tiger grouper, and pink ear emperor). The skin samples were divided into 4 groups (A, B, C and D) and treated with different sample to acetic acid ratios and extraction time of A. [ratio 1:10 (w/v) with 24 h]; B. [ratio 1:10 (w/v) with 36 h]; C. [ratio 1:20 (w/v) with 24 h]; and D. [ratio 1:20 (w/v) with 36 h]. Furthermore, characterization of collagen functional groups was carried out using FTIR while the peptide pattern analysis was carried out with SDS-polyacrylamide gel electrophoresis. The results showed that the collagen yield from the groups was different and the longer the extraction time, the higher the yield. Collagens from the three fishes in the treatment groups had wave spectra that were consistent with the standard collagen amide band while the peptide patterns showed α1 and α2 chains with molecular weights of 93-106 kDa and the dominant amino acids were glycine, proline, and alanine. They were also identified as collagen type 1 with similar protein patterns and FTIR spectra.