The Effect On The Antioxidant Capacity Of Anthocyanins Caused By The Binding Of Anthocyanins With Protein

In this paper, DPPH、FRAP、ORAC methods was used to research the effect on theantioxidant capacity of anthocyanins caused by the binding of anthocyanins withprotein. In order to understand the interaction between anthocyanins and protein, thefluorescence spectroscopy, UV-visabsorbance, Fourier transform infraredspectroscopy, circular dichroism (CD) and molecular modeling techniques wereused. The reason of the antioxidant activity of anthocyanins reduced by the interactionwith protein was discussed. These studies are important for the application ofanthocyanins in the field of health foods and functional beverage. Four chapters areincluded as follows:In the chapter one, the structure and physiological function of anthocyanins, thebasic knowledge of protein, the research progress on the antioxidant activity ofanthocyanins and the progress of research on the effects of antioxidant capacitycaused by the interaction between small molecules and protein were reviewed indetail.In the chapter two, first of all, the mechanism of the interaction betweenCyanidin-3-O-glucoside（C3G）and bovine serum albumin (BSA) by the fluorescencespectroscopy, UV-visabsorbance, Fourier transform infrared spectroscopy, circulardichroism(CD) and molecular modeling techniques were discussed. Then thebinding constant (Ka) and the number of binding sites (n) were calculated. Finally, thequenching mechanism of fluorescence of BSA by C3G was discussed. The result ofmolecular modeling inferred that the main type of binding force between C3G andBSA were hydrogen bonds, and that the hydroxyl groups in the B ring of C3G tookpart in the combination with BSA.In the chapter three, the effect of antioxidant capacity caused by the interaction between Cyanidin-3-O-glucoside and Idei chloride with BSA were studied by usingDPPH、FRAP、ORAC. It showed that the antioxidant capacity of anthocyaninsdeclined because of the binding with BSA by using the statistical analysis.Theanthocyanins didnot play a good role in antioxidant capacity based on the discussionof the anthocyanin serum albumin binding mechanisms in chapter two.In the chapter four, the effects of antioxidant capacity were studied by theinteraction between Cyanidin-3-O-glucoside and idei chloride with casein.The resultsshowed that the antioxidant capacity of anthocyanins was decreased by the bindingwith casein. The combination of casein and the Anthocyanins B ring hydroxyl playeda role in protecting against breaking the anthocyanin antioxidant structure during thetransportation.