Graf E, Empson K L, Eaton J W
J Biol Chem. 1987 Aug 25;262(24):11647-50.
The catalysis by iron of radical formation and subsequent oxidative damage has been well documented. Although many iron-chelating agents potentiate reactive oxygen formation and lipid peroxidation, phytic acid (abundant in edible legumes, cereals, and seeds) forms an iron chelate which greatly accelerates Fe2+-mediated oxygen reduction yet blocks iron-driven hydroxyl radical generation and suppresses lipid peroxidation. Furthermore, high concentrations of phytic acid prevent browning and putrefaction of various fruits and vegetables by inhibiting polyphenol oxidase. These observations indicate an important antioxidant function for phytate in seeds during dormancy and suggest that phytate may be a substitute for presently employed preservatives, many of which pose potential health hazards.
铁催化自由基形成及随后的氧化损伤已得到充分证明。尽管许多铁螯合剂会增强活性氧的形成和脂质过氧化,但植酸(在可食用豆类、谷物和种子中含量丰富)会形成一种铁螯合物,它能极大地加速Fe2+介导的氧还原,同时阻止铁驱动的羟基自由基生成并抑制脂质过氧化。此外,高浓度的植酸通过抑制多酚氧化酶来防止各种水果和蔬菜的褐变和腐烂。这些观察结果表明植酸盐在种子休眠期间具有重要的抗氧化功能,并表明植酸盐可能是目前使用的许多具有潜在健康危害的防腐剂的替代品。