Evidence for Copigmentation Interactions between Deoxyanthocyanidin Derivatives (Oaklins) and Common Copigments in Wine Model Solutions

Abstract

The aim of this study was to investigate interactions possibly taking place in red wine between oaklins, which are deoxyanthocyanidin derivatives (guaiacylcatechin-pyrylium and syringylcatechin-pyrylium), and several copigments: catechin (CP1), epicatechin (CP2), chlorogenic acid (CP3), epigallocatechin (CP4), and procyanidin B3 (CP5). The results show that oaklins, like common anthocyanins, also present copigmentation interactions that further stabilize the flavylium cation in hydroalcoholic solutions. Molecular dynamics simulations were also performed to interpret the binding data, to specify the relative arrangement of the pigment and copigment molecules within the complexes, and to interpret their absorption properties in the visible range.

Copigmentation of malvidin-3-O-glucoside with five hydroxybenzoic acids in red wine model solutions: Experimental and theoretical investigations

“…Besides, such as the ionic strength, pH, solvent, temperature, the presence of metal salts (Asen, Stewart, & Norris, 1972;Raymond Brouillard & Dangles, 1994;Mistry, Cai, Lilley, & Haslam, 1991), the molecular structures of anthocyanins and cofactors are also important for the copigmentation (Sousa et al, 2014). In addition, as a special case, another copigmentation mechanism caused by anthocyanins themselves when their concentrations were higher than 1 mM was also reported, which was named as self-association (Boulton, 2001).…”

Anthocyanin Encapsulated by Ferulic Acid-Grafted-Maltodextrin (FA-g-MD) Microcapsules Potentially Improved its Free Radical Scavenging Capabilities Against H2O2-Induced Oxidative Stress

“…As shown in Figure 4, ANC had a maximum absorption peak at 533nm, which is the characteristic absorption of anthocyanin [28]. Moreover, the combination of ANC and FA-g-MD showed a slight bathochromic shift of λ max as the FA-g-MD concentration increased, which clearly indicated some physically intermolecular interactions [29]. This phenomenon resulted from co-pigmentation effect between ANC and FA-g-MD [30], which may attribute to intermolecular H-bonding or π–π stacking.…”

3‐Deoxyanthocyanidin Colorant: Nature, Health, Synthesis, and Food Applications

“…These compounds exhibit photochromic character, and their physical and chemical properties are similar to common 3‐deoxyanthocyanidins. Oaklins are more stable than anthocyanins, and their ability to copigment with some wine pigments further increases their stability in aqueous solution (Sousa et al., ).…”