Comparative assessment of radical scavenging potential of A1 and A2 cow's milk casein pre- and post-enzymatic hydrolysis

Abstract

This paper aimed to explore the antioxidant activity of A1 and A2 casein hydrolysates and compare their effectiveness. Enzymatic hydrolysis of casein produces bioactive peptides that offer various health benefits, including antioxidant, antihypertensive, antidiabetic, antithrombotic, and immunomodulatory properties. In this study, A1 and A2 casein were hydrolyzed using trypsin at different time intervals (2, 4, and 6 h). The degree of hydrolysis (DH) was determined to assess the extent of peptide bond cleavage during proteolysis. The hydrolysates were then evaluated for their radical scavenging potential using DPPH and ABTS assays, as well as their reducing power. The results indicate that both A1 and A2 casein can be effectively hydrolyzed with trypsin, with 6 h of hydrolysis found to be optimal in terms of DH and scavenger activity. Both A1 and A2 casein hydrolysates demonstrated antioxidant activity against DPPH radical and ABTS radical cation. However, at a high concentration (5% casein), A2 hydrolysate exhibited significantly higher antioxidant activity compared to A1. These findings offer insights into the potential use of A1 and A2 casein hydrolysates as natural antioxidants in functional foods and nutraceuticals, providing a safer and more sustainable alternative to synthetic antioxidants.