2.8. α-Glucosidase Inhibition Activity Assay

This assay was carried out using a commercial kit (Sigma-Aldrich, α-glucosidase Activity Assay Kit, St. Louis, MO, USA). Thus, 20 μL of protein hydrolysate was added to 50 μL of 1 mg/mL of α-glucosidase enzyme from Saccharomyces cerevisiae, then the sample was stored at 37 °C for 5 min, and 200 μL of the Master Reaction Mix containing 200 μL of pH 7 buffer and 8 μL of α-NPG substrate were added and incubated again at 37 °C for 60 min. The absorbance was measured at 405 nm. α-glucosidase inhibition activity (%) = (Absorbance control − Absorbance sample)/(Absorbance control) × 100. Bidistilled water and acarbose were used as the negative and positive control, respectively.