Optimization of different factors affecting antioxidant activity of whey protein hydrolysate by response surface methodology

Background and objectives: Due to safety concerns and health aspects over the use of synthetic antioxidants, the natural antioxidant compounds are considered by researchers. In recent years a great deal of attention for application of natural antioxidants, has led to studies in investigation of antioxidative or bioactive potential of hydrolysates peptides from plant or animal sources. Bioactive peptides are considered specific protein fragments that are inactive within the sequence of the parent protein, after they are released by enzymatic hydrolysis, they may exert various physiological functions such as antioxidative activity. Antioxidant activity of bioactive peptides can be attributed to their radical scavenging, metal ion chelation and inhibition of lipid peroxidation properties of peptides.
Materials and methods: In the present study, response surface methodology was used to optimize hydrolysis conditions for preparing protein hydrolysate from the wey protein, using Alcalase. The investigated factors were temperature (43-55°C), time (60-173 min) and enzyme/substrate ratio (40-90 AU/Kg protein) to achieve maximum antioxidant activity. Experiments were designed according to the central composite design.
Results: The optimal conditions to achieve the highest superoxide free radical scavenging capacitywas, temperature (47/2 °C), time (104/02 min) and enzyme/ substrate ratio (96/85 AU/Kg protein).Under these conditions superoxide free radical scavenging capacity was 63/44 %. Regression coefficient for the model (Quadratic type) was, 0.989 ,The values indicated the high accuracy of the model to predict the reaction conditions considering different variables.Background and objectives: Due to safety concerns and health aspects over the use of synthetic antioxidants, the natural antioxidant compounds are considered by researchers. In recent years a great deal of attention for application of natural antioxidants, has led to studies in investigation of antioxidative or bioactive potential of hydrolysates peptides from plant or animal sources. Bioactive peptides are considered specific protein fragments that are inactive within the sequence of the parent protein, after they are released by enzymatic hydrolysis, they may exert various physiological functions such as antioxidative activity. Antioxidant activity of bioactive peptides can be attributed to their radical scavenging, metal ion chelation and inhibition of lipid peroxidation properties of peptides.
Materials and methods: In the present study, response surface methodology was used to optimize hydrolysis conditions for preparing protein hydrolysate from the wey protein, using Alcalase. The investigated factors were temperature (43-55°C), time (60-173 min) and enzyme/substrate ratio (40-90 AU/Kg protein) to achieve maximum antioxidant activity. Experiments were designed according to the central composite design.
Results: The optimal conditions to achieve the highest superoxide free radical scavenging capacitywas, temperature (47/2 °C), time (104/02 min) and enzyme/ substrate ratio (96/85 AU/Kg protein).Under these conditions superoxide free radical scavenging capacity was 63/44 %. Regression coefficient for the model (Quadratic type) was, 0.989 ,The values indicated the high accuracy of the model to predict the reaction conditions considering different variables. Background and objectives: Due to safety concerns and health aspects over the use of synthetic antioxidants, the natural antioxidant compounds are considered by researchers. In recent years a great deal of attention for application of natural antioxidants, has led to studies in investigation of antioxidative or bioactive potential of hydrolysates peptides from plant or animal sources. Bioactive peptides are considered specific protein fragments that are inactive within the sequence of the parent protein, after they are released by enzymatic hydrolysis, they may exert various physiological functions such as antioxidative activity. Antioxidant activity of bioactive peptides can be attributed to their radical scavenging, metal ion chelation and inhibition of lipid peroxidation properties of peptides.
Materials and methods: In the present study, response surface methodology was used to optimize hydrolysis conditions for preparing protein hydrolysate from the wey protein, using