基于荧光及紫外光谱法对红松种鳞多酚与乳清蛋白相互作用的研究

Interaction between the Polyphenols from Pinus koraiensis Seeds Scales and Whey Protein Studied by Fluorescence and Ultraviolet Spectroscopy

摘要:

利用紫外-可见吸收光谱法和荧光光谱法，研究了红松种鳞多酚与乳清蛋白之间的相互作用及其作用方式。紫外-可见吸收光谱表明：红松种鳞多酚与乳清蛋白发生了相互作用并生成新的复合物，改变了蛋白质芳香族残基在空间结构中所处的微环境，诱导乳清蛋白的构象发生改变。荧光光谱表明：红松种鳞多酚对乳清蛋白有较强的荧光猝灭作用且猝灭类型为生成复合物的静态猝灭作用。通过计算得出在不同温度下其二者相互作用的表观结合常数（KA）分别为：1.111×104 L/mol（25 ℃），2.201×104 L/mol（30 ℃），6.206×104 L/mol（35 ℃），对应的结合位点数（n）分别为：0.885、0.937、1.043。由热力学参数分析确定红松种鳞多酚与乳清蛋白间的相互作用反应是吸热过程，反应的主要作用力是疏水作用力。

Abstract:

The interaction between the polyphenols from Pinus koraiensis seed scales and whey protein and associated modes of action were studied by ultraviolet-visible absorption spectroscopy and fluorescence spectroscopy. The analysis by ultraviolet-visible absorption spectroscopy revealed that the polyphenols from Pinus koraiensis seed scales interacted with whey protein and yielded new complexes, which also changed the microenvironment surrounding the spatial structures of the aromatic residues of proteins, and induced the conformational change of whey protein. The fluorescence spectroscopy analysis showed that the polyphenols had a strong fluorescence quenching effect on the whey protein, and the quenching type belonged to the static quenching of the formed complexes. The apparent binding constants (KA) of their interactions at different temperatures were calculated as: 1.111 × 104 L/mol (25 ℃), 2.201 × 104 L/mol (30 ℃), 6.206×104 L/mol (35 ℃), and the corresponding number of the binding sites (n) were 0.885, 0.937 and 1.043, respectively. The analysis of thermodynamic parameters revealed that the interaction between the polyphenols from Pinus koraiensis seed scales and whey protein was an endothermic process, and the main interactive force was hydrophobic interaction.