Analysis of Molecular Weight Distribution and Antioxidant Activities of Cirrhinus molitorella Skin Collagen Hydrolysates

This paper aims to identify molecular weight (MW) distribution and antioxidant activity of fish skin collagen hydrolysates. The MW distribution of hydrolysates was determined using both size exclusion chromatography and matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Fish skin were treated by the alkaline protease 2,709. The result shows that the optional conditions for hyerolysis were 3 hours, temperature 55°C, pH 10.0, substrate concentration 80 g/L and E/S 4%. The results of both methods indicated that the molecular weight of collagen hydrolysates was from 400 to 1,800 Da, and the peptides' molecular weight was less than 1,400 Da, mostly. The reducing power and antioxidant/radical scavenging activity (1,1-diphenyl-2-picryl-hydrazyl free radical scavenging activity) were determined. The results reveal that the fishskin hydrolysate is a potential source of antioxidants.