Effect of Molecular Weight of Isolated Protein Hydrolysate from Sardinella sindensis Obtained Using Pancratin on the Anti-Oxidative and Anti-Diabetic Properties

The purpose of the present study was to hydrolyze Sardinella sindensis protein isolate by pancreatin enzyme and then fractionation hydrolysate based on molecular weight and finally evaluating and comparing the anti-oxidative and anti-diabetic properties of the fractions with hydrolysate.

Protein isolate from Sardinella sindensis muscle was extracted and then hydrolyzed using pancreatin enzyme in two enzyme/substrate ratio of 2.5 and 5% (W/W) for 2h. The hydrolysates were fractionated into three fractions included FPH-I (<2kDa), FPH-II (2-10kDa) and FPH-III (>10kDa) using an ultrafiltration (UF) membranes. The antioxidant and anti-diabetic activiteis of the fractions and hydrolysate were investigated.

The degree of hydrolysis increased with increasing hydrolysis time and it was significant between 30 and 60 minutes (p<0.05). FPH-III showed the highest DPPH radical scavenging activity. In terms of chelating activity on Fe2+, there was no significant difference between the fractions and hydrolysate (p>0.05). Also, FPH-III showed a better ABTS radical-scavenging activity. FPH-III had the highest inhibitory potential against α-amylase at 2.5%. In addition, the inhibitory effect of samples at 20mg/ml against α-glucosidase was less than 50%.

FPH-III from Sardinella sindensis protein isolate by pancreatin enzyme had the highest DPPH radical scavenging, ABTS+ activity and alpha-amylase inhibitory.