Investigation on the interaction between γ-cyclodextrin and α-amylase
A growing interest has been shown regarding the impact of α-amylase on the quality of fermented foods. Therefore, the interaction between γ-cyclodextrin and α-amylase was investigated in this article. The results showed that γ-cyclodextrin had an inhibitory effect on the activity of α-amylase under certain conditions, obtaining the strongest inhibitory effect when the concentration of γ-cyclodextrin was 10 mmol/L, the reaction temperature was 45 °C, pH = 5.9 and reaction time of 120 min. The results also showed important changes in the secondary structure of α-amylase induced by γ-cyclodextrin, including the transformation of α-helix, β-fold and random coil. Moreover, the addition of γ-cyclodextrin could induce the change of endogenous fluorescence intensity by changing the microenvironment of the α-amylase. According to the results of NMR, a part of the α-amylase molecule enters the cavity of the γ-cyclodextrin, and the other part forms a hydrogen bond with the outer cavity, forming a complex. The experimental results provide references for the application of γ-cyclodextrin and α-amylase.