7种白藜芦醇及其多羟基位衍生物的清除自由基活性机理的理论预测分析  

The study on the structure activity relationship of scavenging free radical activity of 7 kinds of natural antioxidants of resveratrols by quantum chemistry calculation

作　　者：姜伟 张璐 陆豫[2] 余勃[2] 

机构地区：[1]南昌市食品药品检验所,江西南昌330038 [2]南昌大学资源环境与化工学院,江西南昌330047

出　　处：《南昌大学学报（理科版）》2016年第3期269-275,共7页Journal of Nanchang University(Natural Science)

基　　金：国家自然科学基金项目(31301435)

摘　　要：白藜芦醇是一种具有广泛抗氧化活性的多酚类天然化合物,能有效阻断自由基链式反应。为研究白藜芦醇及其相关衍生物的清除自由基的活性机理及性质,本实验设计7种白藜芦醇及其多羟基衍生物结构并构建分子模型,使用Gaussian 09软件通过密度泛函法DFT对7种分子进行量子化学计算。分析发现原子电荷分布图和前线分子轨道图能直观阐述白藜芦醇及其多羟基衍生物的活性基团;羟基位OH电荷差值和前线分子轨道π电子云密度能很好表征各羟基位活性顺序;根据前线分子轨道能级差△E及能隙Egap对照表征预测了白藜芦醇及其多羟基衍生物的活性大小以及各羟基位的活性顺序,其中各羟基的活性顺序4、4’位羟基>3、3’位羟基>5、5’位羟基,且4、4’位羟基位是主要的活性位点,其相应量化参数能作为推测分子抗氧化活性的主要指标。最终预测3,3’,4,4’,5,5’-六羟基反二苯代乙烯是7种白藜芦醇及其多羟基衍生物中抗氧化活性最高的分子结构。通过量子化学计算研究所得结果对高抗氧化活性的白藜芦醇相关衍生物结构的筛选和设计具有理论指导意义。Resveratrol is an antioxidant activity of polyphenolic natural compounds,and it can effectively block the free radical chain reaction.To study the activity mechanism and properties of resveratrol and its derivatives scavenging free radicals,7kinds of resveratrols and their multi hydroxy derivatives were designed and constructed by using Gaussian 09 software and density functional theory（DFT）,and 7 molecules were analyzed by quantum chemistry calculation.Analysis showed that atomic charge distribution and frontier molecular orbital diagram can directly illustrate active groups of resveratrol and their hydroxyl derivatives.Hydroxyl position OH charge difference and frontier molecular orbitalπelectron cloud density well characterize the hydroxy groups of the activity order.The frontier molecular orbital energy difference and energy gap were used to predict the magnitude of the activity of resveratrol together with its hydroxyl derivatives and the activity order of hydroxy groups.The predicted order is 4,4＇hydroxy 〉3,3＇hydroxy〉5,5＇hydroxy,where the 4,4＇hydroxy bit is the main active sites whose corresponding quantization parameter can be specified as the main indicators of the molecular antioxidant activity.The final prediction showed that the 3,3＇4,4＇,5,5＇-six hydroxyl anti diphenyl ethylene has the highest antioxidant activity among seven kinds of resveratrol and their hydroxyl derivatives.The results via quantum chemistry calculation have a theoretical significance for the selection and design of the structure of the resveratrol related derivatives with high antioxidant activity.

关 键 词：白藜芦醇 量子化学计算 自由基 密度泛函法 

分 类 号：O641.121[理学—物理化学]