Abstract: The interaction modes and nanoparticle characteristics of bovine serum albumin (BSA) with quercetin (QUE) and anthocyanin (ACN) were comparatively investigated. The fluorescence of BSA was greatly quenched by QUE in both static (at low concentration) and dynamic (at high concentration) modes, while fluorescence quenching of BSA by ACN was just in a static mode. The binding constant of BSA with QUE was higher than that with ACN. BSA interacted with QUE and ACN by hydrophobic force and electrostatic force, respectively, to form BSA-QUE and BSA-ACN nanoparticles. The average diameters of BSA-QUE and BSA-ACN were 42.5 nm and 53.7 nm, respectively. The ζ-potentials of BSA-QUE and BSA-ACN were −25.64 and −21.50 mV, respectively. One mole of BSA could combine 8 moles of QUE or 10 moles of ACN. BSA-QUE nanoparticles were smaller and more stable than BSA-ACN nanoparticles. The DPPH and ABTS radical scavenging rates of BSA-QUE were higher than those of BSA-ACN.

Key words: bovine serum albumin (BSA), quercetin (QUE), anthocyanin (ACN), interaction, nanoparticle