Studies on the interaction between homological proteins and anthocyanins from purple sweet potato (PSP): Structural characterization, binding mechanism and stability. (30th January 2023)

• Record Type: Journal Article
• Authors: Zhang, Rui; Ye, Shuxin; Guo, Ying; Wu, Muci; Jiang, Sijia; He, Jingren
• Is Part Of: Food chemistry. Volume 400(2023)
• Publication Date: 2023-01-30
• Subjects: Protein-bound anthocyanins -- Interactions -- Purple sweet potato -- Characterization -- Stability -- Anti-ultraviolet; PSP purple sweet potato -- FAC-PSP free anthocyanins from purple sweet potato -- p-BAC-PSP protein-bound anthocyanins from purple sweet potato -- p-PSP proteins from purple sweet potato; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2022.134050
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: The interaction between homological proteins (p-PSP) and anthocyanins (FAC-PSP) was firstly investigated. Their interaction followed a combination of static and dynamic quenching (static dominant). Hydrophobic interactions were dominant for the formation of complex (p-BAC-PSP). An obvious secondary structure change was observed between p-PSP and p-BAC-PSP. The p-BAC-PSP exhibited better stabilities and anti-ultraviolet activity than FAC-PSP. Abstract: The protein-bound anthocyanin complexes are naturally existed in food systems by their spontaneous interaction. In this study, the interaction mechanism of homological proteins (p-PSP) and anthocyanins (FAC-PSP) was investigated to explore the binding characteristic of native protein-bound anthocyanins from purple sweet potato (p-BAC-PSP). The structural characterization, stability and anti-ultraviolet property of p-BAC-PSP were also evaluated. Results revealed that hydrophobic interaction is dominant binding force for forming p-BAC-PSP. The binding resulted in protein secondary structure changes with more β-sheet and lower β-turn, random coil structures. Fluorescence spectroscopy demonstrated that FAC-PSP quenched p-PSP fluorescence in a combination of static and dynamic mode (static dominant) with a binding constant of 10 5 L/mol reflecting strong affinity of FAC-PSP to p-PSP. Moreover, the complex form exhibited better protective effects on anthocyanins for pH, light, thermal stabilities and higher anti-ultraviolet activity. These findings further expanded the application of anthocyanins as stable, functional food and cosmetic ingredients.