酚酸物质抗氧化性及溶剂化效应的理论计算  

Theoretical Calculation on Antioxidative Activity and Solvation Effect of Phenolic Acids

作　　者：卢俊 高涵 卢庆华 王国泽 吕俊丽 王建华 左文欢 LU Jun;GAO Han;LU Qinghua;WANG Guoze;LÜJunli;WANG Jianhua;ZUO Wenhuan(School of Life Science and Technology,Inner Mongolia University of Science and Technology,Baotou 014010,China)

机构地区：[1]内蒙古科技大学生命科学与技术学院,内蒙古包头014010

出　　处：《食品科学》2024年第7期52-60,共9页Food Science

基　　金：内蒙古自治区自然科学基金项目(2021LHMS02005);2023内蒙古大学生创新创业训练项目(202310127011,202310127040);2022年昆区科技计划项目(YF2022016);内蒙古科技大学基本科研业务费专项(2023QNJS143,2022-18;2023RCTD020)。

摘　　要：运用M06-2X泛函对12种酚酸物质进行理论计算,以抗氧化性指标键解离焓(bond dissociation enthalpy,BDE)、电离势(ionization potential,IP)、质子解离焓(proton dissociation enthalpy,PDE)、质子亲和力(proton affinity,PA)和电子转移焓(electron transfer enthalpy,ETE)为理论指标,对酚酸在气相及溶剂中进行分析,阐释其抗氧化性及溶剂化效应。结果表明:以BDE为标准,气相中龙胆酸(C5)的BDE最低;在苯中抗氧化性最好的是咖啡酸(C6),丙酮中为龙胆酸(C5),乙醇和水中为3,4-二羟基苄醇(C2);以IP为标准,在气相及4种溶剂中抗氧化性最好的均为白藜芦醇;就抗氧化机制而言,酚酸物质主要发生氢原子转移机制。通过5种表征抗氧化性指标IP、BDE、PDE、PA和ETE分析得出,无论是酚酸脱氢阴离子还是阳离子,生成脱氢自由基的能力与受到溶剂极性大小的影响一致。总体来说,弱极性溶剂丙酮中的抗氧化能力相对最强,强极性溶剂水和乙醇中抗氧化能力稍弱于丙酮,在非极性溶剂中,酚酸的抗氧化能力相对最弱。In this study,12 phenolic acids were theoretically calculated using the M06-2X functional.To explain their antioxidant and solvation effects,bond dissociation enthalpy(BDE),ionization potential(IP),proton dissociation enthalpy(PDE),proton affinity(PA)and electron transfer enthalpy(ETE)were calculated for each phenolic acid in the gas phase and solvents.The results showed that the BDE of gentianic acid(C5)in the gas phase was the lowest.In terms of BDE,caffeic acid(C6)had the strongest antioxidant effect in benzene,gentianic acid(C5)in acetone,and 3,4-dihydroxybenzyl alcohol(C2)in ethanol and water.In terms of IP,resveratrol had the best antioxidant activity in 4 solvents and in the gas phase.The antioxidant mechanism of phenolic acids was mainly related to hydrogen atom transfer(HAT).It was found that the ability of dehydrogenated anions and cations of phenolic acids to generate dehydrogenated free radicals was consistent with the influence of solvent polarity on IP,BDE,PDE,PA and ETE.In general,the antioxidant capacity of phenolic acids was the strongest in the weakly polar solvent acetone,followed by the strongly polar solvents water and ethanol,and phenolic acids had the weakest antioxidant capacity in non-polar solvents.

关 键 词：酚酸 抗氧化性 溶剂效应 密度泛函理论 

分 类 号：Q617[生物学—生物物理学]