. Aktivitas Antioksidan Peptida Bioaktif dari Protein Kulit Patin (Pangasius sp.) yang Dihidrolisis dengan Enzim Alkalase

Abstract

One of the by-products generated from the pangasius (Pangasius sp.) fillet processing industry is skin, which contains a high protein content and has the potential to be utilized as a raw material for fish protein hydrolysate to produce bioactive components. To date, the use of fish skin has primarily focused on the production of collagen and gelatin, while the direct exploration of protein hydrolysates remains limited. Fish protein hydrolysates have the potential to produce bioactive peptides with various biological activities, including antioxidant properties. This study aimed to determine the optimal defatting conditions through variations in NaHCO3 concentration and soaking time in reducing the fat content of pangasius skin, to evaluate the effect of alcalase enzyme concentration and hydrolysis time on the degree of hydrolysis, and to determine the antioxidant activity of fish protein hydrolysates derived from pangasius skin under selected hydrolysis conditions. The study was conducted in three stages. The first stage involved defatting pangasius skin using NaHCO3 solutions at different concentrations and soaking times to determine the optimal treatment for fat reduction. The second stage was the enzymatic hydrolysis process using alcalase with varying enzyme concentrations and hydrolysis times to evaluate the degree of hydrolysis. The third stage involved characterizing the selected fish protein hydrolysate using antioxidant activity assays with 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) methods, as well as molecular weight analysis. The results showed that defatting with 1% NaHCO3 for 15 minutes yielded the highest fat reduction of 72.4%. The use of alcalase enzyme significantly affected the degree of hydrolysis of pangasius skin protein hydrolysates, with values ranging from 36.72 to 43.55%. The selected hydrolysate exhibited the highest antioxidant activity at 3% enzyme concentration, with IC50 values of 22.08 ppm and 7 ppm for DPPH and ABTS methods, respectively. The resulting protein hydrolysate had a molecular weight ranging from 8.20 to 10.96 kDa, indicating the formation of lowmolecular- weight peptides with potential antioxidant activity.