Topic
Chelating Activity
About: Chelating Activity is a research topic. Over the lifetime, 80 publications have been published within this topic receiving 5923 citations.
Papers published on a yearly basis
Papers
TL;DR: The diversity and multiple mechanisms of flavonoid action, together with the numerous methods of initiation, detection and measurement of oxidative processes in vitro and in vivo offer plausible explanations for existing discrepancies in structure-activity relationships.
Abstract: Flavonoids are a class of secondary plant phenolics with significant antioxidant and chelating properties. In the human diet, they are most concentrated in fruits, vegetables, wines, teas and cocoa. Their cardioprotective effects stem from the ability to inhibit lipid peroxidation, chelate redox-active metals, and attenuate other processes involving reactive oxygen species. Flavonoids occur in foods primarily as glycosides and polymers that are degraded to variable extents in the digestive tract. Although metabolism of these compounds remains elusive, enteric absorption occurs sufficiently to reduce plasma indices of oxidant status. The propensity of a flavonoid to inhibit free-radical mediated events is governed by its chemical structure. Since these compounds are based on the flavan nucleus, the number, positions, and types of substitutions influence radical scavenging and chelating activity. The diversity and multiple mechanisms of flavonoid action, together with the numerous methods of initiation, detection and measurement of oxidative processes in vitro and in vivo offer plausible explanations for existing discrepancies in structure-activity relationships. Despite some inconsistent lines of evidence, several structure-activity relationships are well established in vitro. Multiple hydroxyl groups confer upon the molecule substantial antioxidant, chelating and prooxidant activity. Methoxy groups introduce unfavorable steric effects and increase lipophilicity and membrane partitioning. A double bond and carbonyl function in the heterocycle or polymerization of the nuclear structure increases activity by affording a more stable flavonoid radical through conjugation and electron delocalization. Further investigation of the metabolism of these phytochemicals is justified to extend structure-activity relationships (SAR) to preventive and therapeutic nutritional strategies.
4,281 citations
TL;DR: In this article, the authors determined the iron chelating activity of some medicinal plants and determined to find alternative sources with lower side effects in thalassemic patients by soaking dry material of the selected plant in appropriate solvent.
Abstract: Thalassemia major is characterized by anemia, iron overload, further potentiation of reactive oxygen species (ROS) and damage to major organs, especially the cardiovascular system. Antioxidant and other supportive therapies protect red blood cells (RBC) against antioxidant damage. Chelation therapy reduces iron-related complications and thereby improves quality of life and overall survival. The poor oral bioavailability, short plasma half-life and severe side effects of available chelators are still not optimal. In this study, iron chelating activity of some medicinal plants was determined to find alternative sources with lower side effects in thalassemic patients. Extracts were prepared by soaking dry material of the selected plant in appropriate solvent. Phenol and flavonoid content of the extract were measured by folin ciocalteu and AlCl3 assays. Phenol content of the extracts varied between 9 -290 mg/g. The largest amount of phenolic compounds and highest chelating activity were found in Mellilotus arvensis. All extracts contained various amount of flavonoids from 10 to 60 mg/g. Extracts with high phytochemicals and chelating activity can be observed as a good source of new agents for thalassemic patients.
393 citations
TL;DR: Inhibition of AGE formation results primarily from the chelating or antioxidant activity of the AGE inhibitors, rather than their carbonyl trapping activity.
338 citations
TL;DR: It is concluded that cefIDERocol forms a chelating complex with iron, which is actively transported into P. aeruginosa cells via iron transporters, resulting in potent antibacterial activity of cefiderocol against P.aerug inosa.
Abstract: Cefiderocol (S-649266) is a novel parenteral siderophore cephalosporin conjugated with a catechol moiety at the third-position side chain. The in vitro activity of cefiderocol against Pseudomonas aeruginosa was enhanced under iron-depleted conditions, whereas that of ceftazidime was not affected. The monitoring of [thiazole- 14 C]cefiderocol revealed the increased intracellular accumulation of cefiderocol in P. aeruginosa cells incubated under iron-depleted conditions compared with those incubated under iron-sufficient conditions. Cefiderocol was shown to have potent chelating activity with ferric iron, and extracellular iron was efficiently transported into P. aeruginosa cells in the presence of cefiderocol as well as siderophores, while enhanced transport of extracellular ferric iron was not observed when one of the hydroxyl groups of the catechol moiety of cefiderocol was replaced with a methoxy group. We conclude that cefiderocol forms a chelating complex with iron, which is actively transported into P. aeruginosa cells via iron transporters, resulting in potent antibacterial activity of cefiderocol against P. aeruginosa.
276 citations
TL;DR: Fractions coming from the isolate and phaseolin had similar activities except for iron chelation, suggesting that phaseolin is the major contributor to the antioxidant and copper chelating activities of the hydrolysed protein isolate.
261 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2021 | 2 |
| 2020 | 5 |
| 2019 | 5 |
| 2018 | 2 |
| 2017 | 7 |
| 2016 | 3 |