Grupo de Investigación en Polifenoles (GIP), Departamento de Química Analítica, Nutrición y Bromatología, Facultad de Farmacia, Universidad de Salamanca, Salamanca E37007, Spain.
LAQV, REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, 4169-007 Porto, Portugal.
J Agric Food Chem. 2024 Jan 31;72(4):1894-1901. doi: 10.1021/acs.jafc.2c08502. Epub 2023 Feb 7.
Supramolecular study of the interactions between the major wine anthocyanin, malvidin-3--glucoside (Mv3G) and different wine phenolic compounds (quercetin 3--β-glucopyranoside (QG), caffeic acid, (-)-epicatechin, (+)-catechin, and gallic acid) has been performed at two different molar ratios (1:1 and 1:2) in acidic medium where flavylium cation predominates (pH ≤ 2). Color variations have been evaluated by differential colorimetry using CIELAB color space. These studies have been complemented with isothermal titration calorimetry assays and molecular dynamics simulations. The color of Mv3G flavylium cation is modified by the interaction with QG toward more bluish and intense colors. Interaction constants between the anthocyanin and the different phenolic compounds were obtained, ranging from 9.72 × 10 M for QG to 1.50 × 10 M for catechin. Hydrophobic interactions and H-bonds are the main driving forces in the pigment/copigment aggregation, except for the interactions where caffeic acid is involved, in which hydrophobic interactions acquire greater preponderance.
已在酸性介质中（pH ≤ 2，其中花色素阳离子占优势）以两种不同的摩尔比（1:1 和 1:2）对主要葡萄酒花色苷（矢车菊素-3-O-葡萄糖苷（Mv3G）与不同葡萄酒酚类化合物（槲皮素 3-O-β-吡喃葡萄糖苷（QG）、咖啡酸、（-）-儿茶素、（+）-儿茶素和没食子酸）之间的相互作用进行了超分子研究。使用 CIELAB 颜色空间通过差示比色法评估了颜色变化。这些研究通过等温滴定量热法测定和分子动力学模拟得到了补充。Mv3G 花色素阳离子的颜色通过与 QG 的相互作用而发生变化，向更蓝和更强烈的颜色转变。获得了花色苷与不同酚类化合物之间的相互作用常数，范围从 QG 的 9.72×10^M 到儿茶素的 1.50×10^M。除了涉及咖啡酸的相互作用外，疏水力和氢键是色素/共色素聚集的主要驱动力，在涉及咖啡酸的相互作用中，疏水力占据更大的优势。
