Extraction and Characterization of Type I Collagen from Parrotfish (Scarus sordidus Forsskal, 1775) Scale solubilized with the Aid of Acetic Acid and Pepsin

Waste from marine fish processing is an important source of valuable products. Fish collagen is considered a alternative biomaterial due to its excellent properties, and it is widely used for industrial purposes. Thus, this present study aimed to characterize acid and pepsin-soluble collagens from the waste of parrotfish (Scarus sordidus Forsskal, 1775) scales. The yields (p > 0.05) of acid-soluble collagen (ASC-PFS) and pepsin-soluble collagen (PSC-PFS) were 1.17 g/100 g and 1.00 g/100 g, respectively. Both collagen samples were categorized as type I owing to the presence of two alpha chain subunits (alpha 1 and alpha 1) after being confirmed by a sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Under the fourier transform infrared (FTIR) test, the triple helical structure of type I collagens from the ASC-PFS and PSC-PFS was maintained. Moreover, the study of UV visible spectra and X-ray diffraction (XRD) showed the similarity of collagens derived from different fish species, and the thermostability (T-max) evaluation of all extracted collagens was in the range of 36.22-37.78 degrees C, and their values were comparable to previous research on the fish scale collagens. The effect of various pH and sodium chloride (NaCl) treatments on solubility exhibited that the ASC-PFS and PSC-PFS were highly soluble in an acidic condition (pH < 5.0) and low concentration of sodium chloride (<30 g/L). Taken together, collagens extracted from parrotfish scale waste can be an alternative source for industries.

Automated summary

This study aimed to extract acid-soluble collagen (ASC) and pepsin-soluble collagen (PSC) from parrotfish scale waste and characterize their properties. Both collagen samples were categorized as type I collagens with maintained triple helical structure. The solubility of ASC and PSC was high in acidic condition (pH < 5.0) and low concentration of sodium chloride (<30 g/L). Therefore, collagens extracted from parrotfish scale waste can be a potential alternative source for industries.