Mechanistic study on inhibition of porcine pancreatic α-amylase using the flavonoids from dandelion.

This study was designed to investigate quantitatively the inhibition and molecular mechanism of pancreatic α-amylase exhibited by flavonoids from dandelion to reveal its potential use in relieving postprandial hyperglycemia. The results show that the flavonoids reversibly inhibited the α-amylase in a non-competitive manner with Michaelis-Menten constant (Km) and half-inhibitory concentration (IC50) value of 10.51 and 0.0067 mg/mL, respectively. The flavonoids present a strong ability to quench the intrinsic fluorescence of α-amylase through static quenching by forming a complex. The values of the binding site (n) at different temperatures were found to be approximately the unity, indicating the presence of a single class of molecular binding of the dandelion flavonoids on α-amylase. The positive values of enthalpy and entropy change reveal that the binding was predominately driven by hydrophobic interactions. This study suggests a benefit of incorporating the dandelion flavonoids in making functional foods in managing the diet of the diabetes.