ANTIOXIDANT PROPERTIES OF CATFISH SKIN PROTEIN HYDROLYSATES

ABSTRACT Diabetes mellitus is a chronic metabolic disorder characterized by persistent hyperglycemia, often accompanied by increased oxidative stress, which contributes to the progression of diabetic complications. Antioxidant peptides derived from natural protein sources have emerged as potential therapeutic agents for managing oxidative stress associated with diabetes. This study investigates the antioxidant properties of protein hydrolysates obtained from catfish skin, an underutilized by-product rich in collagen and bioactive compounds. Catfish skin protein was isolated and subjected to enzymatic hydrolysis to obtain peptide-rich hydrolysates. The percentage protein yield from isolation and peptide yield after hydrolysis were determined to assess the efficiency of extraction and hydrolysis processes. The degree of hydrolysis (DH) was measured to evaluate the extent of protein breakdown, which correlates with bioactivity. Antioxidant activities of the hydrolysates were assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, Ferric Reducing Antioxidant Power (FRAP), and superoxide radical scavenging activity assays. The results indicated a high protein yield and peptide content, indicating the viability of using catfish skin for bioactive peptide synthesis. In all experiments, the hydrolysates demonstrated considerable antioxidant activity, including free radical scavenging and ferric ion imhibition. These findings indicate that catfish skin protein hydrolysates have excellent antioxidant capabilities and may help combat the oxidative stress associated with diabetes mellitus. The study supports the potential application of catfish-derived peptides as functional food ingredients or nutraceuticals in diabetes management. Keywords: Catfish, Diabetes mellitus, Antioxidant, Hydrolysates