Interactions of Natural Flavones with Iron Are Affected by 7--Glycosylation, but Not by Additional 6″-Acylation.

In iron-fortified bouillon, reactivity of the iron ion with (acylated) flavone glycosides from herbs can affect product color and bioavailability of iron. This study investigates the influence of 7--glycosylation and additional 6″--acetylation or 6″--malonylation of flavones on their interaction with iron. Nine (6″--acylated) flavone 7--apiosylglucosides were purified from celery (), and their structures were elucidated by mass spectrometry (MS) and nuclear magnetic resonance (NMR).

Reactivity of Fe(III)-containing pyrophosphate salts with phenolics: complexation, oxidation, and surface interaction.

Mixed pyrophosphate salts with the general formula CaFe(PO) potentially possess less iron-phenolic reactivity compared to ferric pyrophosphate (FePP), due to decreased soluble Fe in the food-relevant pH range 3-7. We investigated reactivity (i.e.

Transition metal cations catalyze O/O exchange of catechol motifs with HO.

Catechol motifs are ubiquitous in nature, as part of plant, animal and microbial metabolites, and are known to form complexes with various metal cations. Here, we report for the first time that complexation with transition metal cations, especially Fe(III), results in rapid O/O exchange of the catecholic hydroxyl groups with HO. We discuss the implications of this finding for mechanistic studies using HO and potential relevance for production of O-labeled catechol derivatives.

Unravelling discolouration caused by iron-flavonoid interactions: Complexation, oxidation, and formation of networks.

Iron-flavonoid interactions in iron-fortified foods lead to undesirable discolouration. This study aimed to investigate iron-mediated complexation, oxidation, and resulting discolouration of flavonoids by spectrophotometric and mass spectrometric techniques. At pH 6.

Revealing the main factors and two-way interactions contributing to food discolouration caused by iron-catechol complexation.

Fortification of food with iron is considered to be an effective approach to counter the global health problem caused by iron deficiency. However, reactivity of iron with the catechol moiety of food phenolics leads to discolouration and impairs bioavailability. In this study, we investigated the interplay between intrinsic and extrinsic factors on food discolouration caused by iron-catechol complexation.