光谱法研究抗氧化剂、DPPH与人血清蛋白三元体系的作用

选取几种天然抗氧化剂杨梅素、桑色素、辣椒碱、甜菜碱作为研究对象，运用荧光光谱法、同步荧光光谱法以及三维荧光光谱法研究了几种抗氧化剂以及DPPH自由基与人血清蛋白相互作用，结果表明辣椒碱、甜菜碱、V_C不与人血清蛋白发生猝灭反应，杨梅素、桑色素、DPPH均能够与人血清蛋白发生猝灭反，反应均为形成了稳定复合物而导致的静态猝灭，通过疏水作用力与HSA结合，结合位点数均为1，主要结合位点在色氨酸基团附近，DPPH与人血清蛋白猝灭过程改变了人血清蛋白结构的疏水性，引起蛋白质构象发生变化，而杨梅素、桑色素与人血清蛋白相互作用未造成其构象发生了变化。运用荧光光谱法研究了几种抗氧化剂抑制DPPH直接损伤人血清蛋白的能力，杨梅素、桑色素、辣椒碱、甜菜碱、V_C对DPPH损伤HSA的抑制率分别为25%，18.30%，85.38%，4.02%和84.58%。根据分子结构分析辣椒碱主要通过清除DPPH自由基作用从而抑制其损伤人血清蛋白，根据二元体系反应结果可知杨梅素与桑色素三元体系反应过程中两种抗氧化剂与DPPH竞争结合位点，因此杨梅素、桑色素主要通过占据结合位点的方式抑制DPPH损伤人血清蛋白，而甜菜碱既不能占据结合位点也不能清除自由基，因而抑制能力最弱。分析表明几种天然抗氧化剂的抑制能力与其分子结构中主要官能团结构密切相关。

The Effects of Antioxidant,DPPH and Human Serum Albumin Ternary System Studied by Spectrophotometry

In this study, the natural antioxidants myricetin, morin, capsaicin and betaine were selected as the research objects, and the interaction between several antioxidants, DPPH free radical and human albumin was studied by synchronous fluorescence spectroscopy and three-dimensional fluorescence spectroscopy. Results showed that capsaicin, betaine, VC do not have quench effects with human serum albumin, and myricetin, morin and DPPH have quench effects with human albumin. The reactions are static quenching caused by stable complexes, combining hydrophobic interaction with HSA.,The binding sites are 1, the main binding sites are near the tryptophan groups, and DPPH and human serum albumin’s quenching process changes the structure of human serum protein hydrophobicity, causes protein conformation changes, and the interaction between myricetin, morin and human albumin does notcause its conformation changes. Fluorescence spectroscopy were used to study the inhibitory effect of several antioxidants on DPPH-induced direct damage to human serum albumin. The inhibition rate of myricetin, morin, capsaicin, betaine and VC to DPPH damage HSA was 25%, 18.30%, 85.38%, 4.02% and 84.58%. Capsaicin inhibits the damage of human serum albumin by inhibiting the action of DPPH. The binary system reaction results showed that myricetin reacted with Morin ternary system to form competitive binding sites with DPPH, and Myricetin and Morin inhibit DPPH damage to human serum albumin by occupying binding sites, while Betaine can neither occupy the binding sites nor scavenge free radicals, so the inhibition ability is the weakest. The results showed that the inhibitory ability of several natural antioxidants is closely related to the main functional groups in the molecular structure.