Current State of Knowledge on the Antioxidant Effects and Mechanisms of Action of Polyphenolic Compounds

Abstract

Quality-of-life improvements have resulted in increasing attention being paid to research on antiaging and antioxidation. Polyphenols are natural antioxidants with excellent biological activities, such as antioxidation and scavenging of free radicals and antiviral activity. Abundant availability and low toxicity of polyphenols have attracted the attention of researchers. In this paper, the antioxidant activities of flavonoids, phenolic acids, stilbenes and lignan polyphenols are analyzed, the corresponding antioxidant mechanisms are investigated, and the antioxidant effects of polyphenols are systematically reviewed. Thus, an effective reference based on the recent literature is compiled for the study of the antioxidant mechanisms of polyphenols that provides a significant theoretical basis for the development of products that are components of polyphenols.

Antioxidant, Antihypertensive, Hypoglycaemic and Nootropic Activity of a Polyphenolic Extract from the Halophyte Ice Plant (Mesembryanthemum crystallinum)

“…Diosmin has been reported as a potent antioxidant in in vitro and in vivo studies [ 54 ]. The antioxidant effect of the flavonoids and phenolic acids found in the extract could be attributed to the presence of hydroxyl groups in their structure, which may act as hydrogen donors and directly scavenge reactive oxygen free radicals, thus reducing their activity, as well as the ability to chelate metal ions [ 55 ]. It cannot be ruled out that the antioxidant activity was also the result of a synergistic effect of the phenolic compounds with other unidentified compounds that may be present in the fraction.…”

“…It cannot be ruled out that the antioxidant activity was also the result of a synergistic effect of the phenolic compounds with other unidentified compounds that may be present in the fraction. The activity would then be superior to that of each of the individual components [ 55 ].…”

Glycosylation of Epigallocatechin Gallate by Engineered Glycoside Hydrolases from Talaromyces amestolkiae: Potential Antiproliferative and Neuroprotective Effect of These Molecules

“…The antioxidant capacity of phenolic compounds such as EGCG depends on the presence of free hydroxyl groups, which act as hydrogen donors to scavenge reactive oxygen free radicals. Therefore, it is expected that the glycosylation of these compounds causes a worsening of their antioxidant capacity, since some of the OH of the aglycon have disappeared when the glycosidic bonds are formed [ 28 , 29 ]. This activity loss was also reported in the glycosides of other phenolic compounds such as phloretin [ 30 ], resveratrol [ 31 ], and gallic acid [ 32 ], as well as EGCG [ 14 ].…”

Profiling of bioactive compounds and antioxidant activity of aquatic weedIpomoea aquatica

“…These bioactive mixes are acknowledged for their oxide reduction properties (Diep et al., 2020; Khan et al., 2020; Št'astná et al., 2019), which might assume a momentous role in the mopping up of ROS and resultant antioxidant activity. The phenolic hydroxyl groups of polyphenol compounds act as hydrogen donors to directly react with radicals and reduce the activities of •O 2 −, H 2 O 2 , •OH, ROO•, 1 O 2 and other active radicals; polyphenol compounds lessen the formation of free radicals by inhibiting the enzyme activities required to produce free radicals; polyphenol compounds chelate metal ions that prompt free radical production, thus reducing the generation of free radicals; polyphenol compounds inhibit oxidation reactions by increasing the activity of antioxidant enzymes or the expression of antioxidant proteins; and polyphenol compounds generate synergistic antioxidant effects with other substances (Lv et al., 2021; Santos‐Sánchez et al., 2019). Polyphenols and polyphenol‐rich diets boost antioxidant defences, immunological response, disease resistance, reproductive performance, growth performance, proximate body composition, digestive enzyme activities and gut bacterial community diversity, among other things (Elumalai et al., 2020; Ji et al., 2018; Volpe et al., 2018).…”