Institute of Nutritional and Food Sciences, Molecular Food Technology , University of Bonn , Endenicher Allee 19b , D-53111 Bonn , Germany.
J Agric Food Chem. 2019 Aug 21;67(33):9344-9353. doi: 10.1021/acs.jafc.9b03108. Epub 2019 Aug 12.
Anthocyanins determine the color and potential health-promoting properties of red fruit juices, but the juices contain remarkably less anthocyanins than the fruits, which is partly caused by the interactions of anthocyanins with the residues of cell wall polysaccharides like pectin. In this study, pectin was modified by ultrasound and enzyme treatments to residues of polysaccharides and oligosaccharides widely differing in their molecular weight. Modifications decreased viscosity and degrees of acetylation and methylation and released smooth and hairy region fragments. Native and modified pectin induced different effects on the concentrations of individual anthocyanins after short-term and long-term incubation caused by both hydrophobic and hydrophilic interactions. Results indicate that both pectin and anthocyanin structure influence these interactions. Linear polymers generated by ultrasound formed insoluble anthocyanin complexes, whereas oligosaccharides produced by enzymes formed soluble complexes with protective properties. The structure of the anthocyanin aglycone apparently influenced interactions more than the sugar moiety.
花色苷决定了红色果汁的颜色和潜在的促进健康的特性，但果汁中的花色苷含量明显低于水果，这部分是由于花色苷与果胶等细胞壁多糖的残留物相互作用造成的。在这项研究中，果胶通过超声和酶处理被修饰成分子量差异很大的多糖和寡糖残基。修饰降低了粘度和乙酰化及甲基化程度，并释放出光滑和多毛区域的片段。天然果胶和修饰后的果胶通过疏水和亲水相互作用，在短期和长期孵育后，对单个花色苷浓度产生不同的影响。结果表明，果胶和花色苷结构都影响这些相互作用。超声产生的线性聚合物形成不溶性的花色苷复合物，而酶产生的寡糖则形成具有保护作用的可溶性复合物。花色苷糖苷元的结构显然比糖基部分更能影响相互作用。
