3.3. In Vitro α-Amylase Inhibition Assay

α-amylase inhibition was tested using previously reported methods [11] 50 µL of the CSEs or control (Acarbose) in DMSO (final concentration 50 µg/mL) were taken in test tubes to which 100 µL of porcine pancreatic α-amylase (5 U/mL) and 460 µL of 0.05 M sodium phosphate buffer pH 6.8 were added. The tubes were then incubated at 37 °C for 10 min. Next, 450 µL of 0.5% starch solution was added and the tubes were incubated for a further 20 min at 37 °C. Finally, 500 µL of Dinitro Salicylic Acid (DNSA) reagent was added and the tubes were placed in a boiling water bath for 15 min. The absorbance of the tubes was recorded at 540 nm and the % inhibition calculated using the same formula as for α-glucosidase,