Structural changes and molecular mechanism study on the inhibitory activity of epigallocatechin against α-glucosidase and α-amylase

Abstract

In this study, the inhibition and mechanism of epigallocatechin (EGC) on two key glycoside hydrolases (α-glucosidase, α-amylase) were explored from the molecular structure level. The chemical structure of EGC was characterized by X-ray diffraction, Fourier transform infrared (FTIR) spectroscopy, and proton nuclear magnetic resonance spectroscopy. EGC’s inhibition on these enzymes was colorimetrically determined. The effects of EGC on the chemical structure and spatial configuration of the enzymes were explored via FTIR spectroscopy, fluorescence spectroscopy, and molecular docking techniques. The results showed that EGC exhibited the inhibition of α-glucosidase and α-amylase in a non-competitive manner, showing a continuous upward trend as EGC’s concentration increased. There was a fluorescence quenching effect of EGC on α-glucosidase and α-amylase. Molecular docking confirmed that EGC can bind to amino acid residues in the enzyme through intermolecular hydrogen bonds and hydrophobic interactions, resulting in the changed chemical structure and spatial conformation of the enzymes. This decreased enzyme activity. This result suggested that EGC has the potential to inhibit two key glycoside hydrolases, and it would be beneficial to incorporate EGC into functional foods for diabetics.

Design and Preparation of a Bifunctional Nanobiohybrid Catalyst by Combining Palladium and α‐Amylase Enzyme: Application in One‐pot Chemoenzymatic Catalysis

“…Additionally, the absorption band positioned at 1286 cm −1 is assigned to the amide III bond which is due to the C−O−C stretching vibration. In the literature, similar findings were observed, and the appearance of bands 1400–1600 cm −1 and 1100–1300 cm −1 were attributed to the amide II and amide III bands respectively [19] . The detected spectral vibrations of catalyst (IV) validate the stable binding of α‐amylase over functionalized HNTs.…”

“…In the literature, similar findings were observed, and the appearance of bands 1400-1600 cm À 1 and 1100-1300 cm À 1 were attributed to the amide II and amide III bands respectively. [19] The detected spectral vibrations of catalyst (IV) validate the stable binding of α-amylase over functionalized HNTs. Along with this, it verifies the actual structural integrity of HNTs after profitable anchoring of αamylase over functionalized HNTs.…”

Phytochemical Profile, Antioxidant, Enzyme Inhibition, Acute Toxicity, In Silico Molecular Docking and Dynamic Analysis of Apis Mellifera Propolis as Antidiabetic Supplement

“…Inhibiting α‐AE and α‐GE can reduce the digestion of carbohydrates, thereby decreasing the absorption of glucose into the bloodstream. This could help maintain blood glucose levels within a healthy range, which is important for managing diabetes and preventing complications [4,24] . Our observation results of the α‐AE and α‐GE inhibitory assays are presented in Figure 2.…”

“…This could help maintain blood glucose levels within a healthy range, which is important for managing diabetes and preventing complications. [4,24] Our observation results of the α-AE and α-GE inhibitory assays are presented in Figure 2. The higher concentration of propolis in 1000 μg/ml could inhibit 75.84 % of α-GE activity with an IC50 value of 1525.36 � 59.246 μg/ml.…”