The inhibitory mechanism of chlorogenic acid and its acylated derivatives on α-amylase and α-glucosidase

Due to the poor lipophilicity of chlorogenic acid (CA), five CA derivatives (C2-CA, C4-CA, C6-CA, C8-CA, and C12-CA) with different lipophilicities were synthesized using acylation catalyzed by lipase in present study. The inhibitory activities and mechanisms of CA and its derivatives on α-amylase and α-glucosidase were then determined. Results showed that the inhibitory activities of CA derivatives on α-amylase and α-glucosidase were enhanced as lipophilicity increased, and the inhibitory activities of C12-CA were stronger than those of CA. IC50 values of C12-CA were 13.30 ± 0.26 μmol/mL for α-amylase and 3.42 ± 0.10 μmol/mL for α-glucosidase. C12-CA possessed the smallest Kic and Kiu values, and its inhibitory actions on α-amylase and α-glucosidase were stronger than those of CA and the other derivatives. Effects of C12-CA on microenvironments of amino acid residues and secondary structures of α-amylase and α-glucosidase were greater than those of CA and the other derivatives.