Natural phenolic compounds are abundant in the vegetable kingdom, occurring mainly as secondary metabolites in a wide variety of chemical structures. Around 10,000 different plant phenolic derivatives have been isolated and identified. This review provides an exhaustive overview concerning the electron transfer reactions in natural polyphenols, from the point of view of their in vitro antioxidant and/or pro‐oxidant mode of action, as well as their identification in highly complex matrixes, for example, fruits, vegetables, wine, food supplements, relevant for food quality control, nutrition, and health research. The accurate assessment of polyphenols’ redox behavior is essential, and the application of the electrochemical methods in routine quality control of natural products and foods, where the polyphenols antioxidant activity needs to be quantified in vitro, is of the utmost importance. The phenol moiety oxidation pathways and the effect of substituents and experimental conditions on their electrochemical behavior will be reviewed. The fundamental principles concerning the redox behavior of natural polyphenols, specifically flavonoids and other benzopyran derivatives, phenolic acids and ester derivatives, quinones, lignins, tannins, lignans, essential oils, stilbenes, curcuminoids, and chalcones, will be described. The final sections will focus on the electroanalysis of phenolic antioxidants in natural products and the electroanalytical evaluation of in vitro total antioxidant capacity.

中文翻译：

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天然酚类抗氧化剂电化学：迈向新的食品科学方法

天然酚类化合物在植物界中含量丰富，主要作为多种化学结构的次生代谢物存在。已经分离和鉴定了大约 10,000 种不同的植物酚类衍生物。这篇综述从体外的角度对天然多酚中的电子转移反应进行了详尽的概述。抗氧化剂和/或促氧化作用模式，以及它们在高度复杂的基质中的识别，例如，水果、蔬菜、葡萄酒、食品补充剂，与食品质量控制、营养和健康研究相关。多酚氧化还原行为的准确评估是必不可少的，电化学方法在天然产品和食品的常规质量控制中的应用，其中多酚的抗氧化活性需要在体外定量, 是最重要的。将回顾苯酚部分的氧化途径以及取代基和实验条件对其电化学行为的影响。将描述关于天然多酚，特别是黄酮类和其他苯并吡喃衍生物、酚酸和酯衍生物、醌、木质素、单宁、木脂素、精油、芪、姜黄素和查耳酮的氧化还原行为的基本原理。最后几节将重点介绍天然产物中酚类抗氧化剂的电分析和体外总抗氧化能力的电分析评估。