牛血清白蛋白与槲皮素及花青素相互作用方式及其纳米颗粒特征的比较

摘要

实验比较了牛血清白蛋白(bovine serum albumin,BSA)与脂溶性小分子槲皮素(quercetin,QUE)和水溶性花青素(anthocyanin,ACN)相互作用方式及其纳米颗粒的特征.QUE对BSA荧光猝灭作用为静态猝灭方式(低浓度),但在较高浓度时为静态与动态并存的复合猝灭方式,两者的相互作用力为疏水作用力;ACN对BSA的荧光猝灭程度小于QUE对BSA的,为静态猝灭方式,相互作用力为静电作用力.BSA与QUE的结合常数大于BSA与ACN的结合常数.BSA与QUE或ACN相互作用可形成纳米颗粒,其大小分别为42.5 nm和53.7 nm,ξ-电势分别为-25.64 mV和-21.50 mV.1 mol BSA分子可分别与8 mol QUE和10molACN结合.BSA与QUE形成的纳米颗粒(BSA-QUE)粒径较BSA与ACN (BSA-ACN)的小,且稳定性较高.BSA-QUE对DPPH自由基和ABTS+·清除率均高于BSA-ACN.%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 ξ-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.