Physicochemical stability-increasing effects of anthocyanin via a co-assembly approach with an amphiphilic peptide

To enhance the stability of anthocyanin, an amphiphilic peptide C6 with tryptophan amino acid was used to co-assemble with anthocyanin C3G. The characterization, stabilities, and antioxidant activity of peptide-anthocyanin (C6-C3G) nanocomposites (70.82 +/- 12.41 nm) were investigated. To illustrate the interaction between peptide and anthocyanin, circular dichroism spectroscopy and fluorescence quenching method were used. Here, the peptide C6 switches from random coil structure to beta-sheet structure and the fluorescence of tryptophan amino acid in peptide quenched during the intermolecular interaction between them, which was further confirmed a static quenching. The nanocomposites significantly enhance the stabilities of anthocyanin to different alkaline conditions, high temperature of 80 degrees C, long time storage, and various concentration of Cu2+ ion. In addition, it maintained the excellent intrinsic capacity of anthocyanin to scavenge free radicals. The approach of using an amphiphilic peptide to enhance the stabilities of anthocyanin presents a high potential to expand its application.

Automated summary

The study utilized an amphiphilic peptide with tryptophan amino acid to co-assemble with anthocyanin, resulting in nanocomposites with enhanced stability and antioxidant activity. The interaction between peptide and anthocyanin was characterized using spectroscopy and fluorescence methods, demonstrating the potential for expanding the application of anthocyanin through this approach.