Protection of ascorbic acid from copper(II)-catalyzed oxidative degradation in the presence of flavonoids: quercetin, catechin and morin
Protection of ascorbic acid from copper(II)-catalyzed oxidative degradation in the presence of flavonoids: quercetin, catechin and morin
复制标题
DOI：
10.3109/09637486.2011.552486
复制
发表时间：
2011-08-01
影响因子：
3.9
通讯作者：
Apak, Resat
中科院分区：
文献类型：
--
作者：
Beker, Bilge Yildogan;Sonmezoglu, Inci;Apak, Resat
保护抗坏血酸（AA）（维生素C）免受Cu（II）催化的自氧化是抗氧化剂化学的一个重要方面。AA的自氧化的存在和不存在的Cu（II）离子的情况下，在通气的溶液中，在室温和I = 0.1的离子强度（KNO3）的影响进行了研究，三种不同的黄酮类化合物的类似结构（槲皮素，桑色素和儿茶素）和它们的混合物上的AA系统进行了研究。用改进的铜离子还原抗氧化能力分光光度法测定了溶液中残留的未氧化AA浓度。在pH 4.5的Cu（II）催化氧化遵循一级动力学相对于AA浓度。稳定的槲皮素和桑色素配合物的Cu（II）比儿茶素复合物的AA的催化自氧化抑制到更大的程度。混合物的抑制有效性顺序提供了有关类黄酮抗氧化剂可能的协同或拮抗组合的信息，这应进一步证实与其他抗氧化剂试验。
Protection of ascorbic acid (AA) (vitamin C) from Cu(II)-catalyzed autoxidation is an important aspect of antioxidant chemistry. The autoxidation of AA in the absence and presence of Cu(II) ions was investigated in aerated solution at room temperature and I = 0.1 ionic strength (KNO3); the effects of three different flavonoids of similar structure (quercetin, morin and catechin) and their mixtures on the AA system were studied. The concentration of unoxidized AA remaining in solution was measured with the modified cupric ion reducing antioxidant capacity spectrophotometric method. The Cu(II)-catalyzed oxidation at pH 4.5 followed first-order kinetics with respect to AA concentration. Catalytic autoxidation of AA was inhibited to a greater extent by stable quercetin and morin complexes of Cu(II) than by catechin complex. The inhibitive effectiveness order of mixtures gives information about possible synergistic or antagonistic combinations of flavonoid antioxidants, which should be further confirmed with other antioxidant tests.