A Review on Coordination Properties of Al(III) and Fe(III) toward Natural Antioxidant Molecules: Experimental and Theoretical Insights

Abstract

This review focuses on the ability of some natural antioxidant molecules (i.e., hydroxycinnamic acids, coumarin-3-carboxylic acid, quercetin, luteolin and curcumin) to form Al(III)- and Fe(III)-complexes with the aim of evaluating the coordination properties from a combined experimental and theoretical point of view. Despite the contributions of previous studies on the chemical properties and biological activity of these metal complexes involving such natural antioxidants, further detailed relationships between the structure and properties are still required. In this context, the investigation on the coordination properties of Al(III) and Fe(III) toward these natural antioxidant molecules might deserve high interest to design water soluble molecule-based metal carriers that can improve the metal’s intake and/or its removal in living organisms.

Caffeic Acid/Eu(III) Complexes: Solution Equilibrium Studies, Structure Characterization and Biological Activity

“…There is also a more recent study from Beneduci et al [ 60 ], but performed at T = 310.15 K. In contrast, due to the fast reduction of Fe 3+ in aqueous solution in the presence of CFA, no data regarding Fe 3+ /CFA system were reported [ 61 ]. Concerning other ligands, it is worth comparing the chelation properties of CFA towards Eu 3+ with those of the simple catechol system [ 62 ] and gallic acid (3,4,5-trihydroxybenzoic acid) [ 63 ] towards the same cation.…”

Modeling the Solubility of Phenolic Acids in Aqueous Media at 37 °C

“…A variety of phenolic compounds are currently among the most studied categories of natural antioxidants [1]. Phenolic acids contain one or more hydroxyl groups (polar part) attached to an aromatic ring (non-polar part) and are often found in plants as esters or glycosides [1][2][3][4][5][6].…”

“…A variety of phenolic compounds are currently among the most studied categories of natural antioxidants [1]. Phenolic acids contain one or more hydroxyl groups (polar part) attached to an aromatic ring (non-polar part) and are often found in plants as esters or glycosides [1][2][3][4][5][6]. Due to their ubiquitous presence in plant-based foods (fruit, vegetables, grain, tea, coffee, spices), the intake of phenolic acids is estimated as 25 × 10 −3 -1 g per day, depending on diet [7].…”

“…In general, the solubility of a non-electrolyte can increase or decrease by the addition of an electrolyte, but the effect is dependent on the solvent salt used. Equation (1) relates the solubility of the neutral species, S • , to its activity coefficients, γ:…”

Antiradical and Membranotropic Actions of Quercetin and Its Complex With Aluminum

“…Хотя соединения алюминия не так токсичны, как тяжелые металлы, чрезмерное поступление алюминия в организм человека может вы-звать серьезные проблемы со здоровьем, такие как повреждение нервной системы, потеря памяти, болезнь Альцгеймера, анемия, остеомаляция, неврологический синдром [7]. В одном из последних обзоров [8] большое внимание уделяется способности природных молекул антиоксидантов, в частности кверцетина, образовывать комплексы Al (III) и Fe (III) с целью оценки координационных свойств, так как структурная характеристика комплексов (схема 1) имеет первостепенное значение для понимания их потенциальной применимости.…”