Role of Uronic Acid Polymers on the Availability of Iron to Plants
Role of Uronic Acid Polymers on the Availability of Iron to Plants
复制标题
糖醛酸聚合物对植物铁利用率的作用
DOI：
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发表时间：
2003
期刊：
影响因子：
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通讯作者：
C. Marzadori
中科院分区：
文献类型：
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作者：
S. Deiana;A. Premoli;C. Senette;C. Gessa;C. Marzadori
摘要研究了聚半乳糖醛酸在丙酮酸、苹果酸和柠檬酸存在和不存在的情况下与铁（III）的相互作用。动力学数据和FT - IR分析表明，多糖基体作为铁（III）的蓄能器，金属离子与多糖基体的羧基和其他官能团发生静电相互作用。铜（II）离子对多糖的羧基有很高的亲和力，对铁（III）的吸收没有明显的影响，这表明羧基在铁（III）的积累过程中不是决定性的。此外，结果表明原纤维内的铁以水解形式或作为铁（III）羟基聚合物存在。在苹果酸和柠檬酸的存在下，铁（III）在pH为4.7和6.0时的积累量明显低于丙酮酸的存在，这是由于柠檬酸和苹果酸对金属离子的亲和力更高。
Abstract The interaction between polygalacturonic acid and Fe(III) was studied in the presence and in the absence of pyruvic, malic, and citric acids. Kinetical data and FT‐IR analyses show that the polysaccharidic matrix acts as an accumulator of Fe(III) and that the metal ion interacts electrostatically with both the carboxylic and other functional groups of the polysaccharidic matrix. Copper(II) ions, which have a high affinity towards the carboxylic groups of the polysaccharide, do not influence markedly the Fe(III) absorption indicating that the carboxylic groups are not determining in the Fe(III) accumulation process. Furthermore, the results suggest that iron inside the fibrils is under an hydrolyzed form or as Fe(III) hydroxy polymer. In the presence of malic and citric acids the amount of Fe(III) accumulated at pH 4.7 and 6.0 is markedly lower than that found in the presence of pyruvic acid what was attributed to the higher affinity of citric and malic acid towards the metal ion.