Phytate: impact on environment and human nutrition. A challenge for molecular breeding
Phytate: impact on environment and human nutrition. A challenge for molecular breeding
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DOI：
10.1631/jzus.b0710640
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发表时间：
2008-03-01
影响因子：
5.1
通讯作者：
Rasmussen, Soren K.
中科院分区：
文献类型：
--
作者：
Bohn, Lisbeth;Meyer, Anne S.;Rasmussen, Soren K.
植酸（Phyticacid，PA）是种子中磷的主要贮藏化合物，占种子总磷的80%以上，占种子干重的1.5%。PA中带负电荷的磷酸盐与Ca、Fe、K、Mg、Mn和Zn的金属阳离子强烈结合，使它们不溶，因此不能作为营养因子。植酸主要积累在蛋白质储存液泡中，呈球状，主要位于糊粉层（小麦、大麦和水稻）或胚（玉米）中。在发芽过程中，植酸盐被内源性植酸酶和其他磷酸酶水解，释放磷酸盐、肌醇和微量营养素，以支持发芽的幼苗。PA及其衍生物还涉及RNA输出、DNA修复、信号传导、内吞作用和细胞囊泡运输。本文介绍了我们近年来在植酸球状体的纯化、矿物组成及植酸酶脱植酸方面的研究。本文介绍了从23种植物中分离纯化的植酸酶的生化数据，比较了不同种类植酸酶对植酸的脱磷酸化途径，并讨论了植酸酶在食品和饲料中的应用。
Phytic acid (PA) is the primary storage compound of phosphorus in seeds accounting for up to 80% of the total seed phosphorus and contributing as much as 1.5% to the seed dry weight. The negatively charged phosphate in PA strongly binds to metallic cations of Ca, Fe, K, Mg, Mn and Zn making them insoluble and thus unavailable as nutritional factors. Phytate mainly accumulates in protein storage vacuoles as globoids, predominantly located in the aleurone layer (wheat, barley and rice) or in the embryo (maize). During germination, phytate is hydrolysed by endogenous phytase(s) and other phosphatases to release phosphate, inositol and micronutrients to support the emerging seedling. PA and its derivatives are also implicated in RNA export, DNA repair, signalling, endocytosis and cell vesicular trafficking. Our recent studies on purification of phytate globoids, their mineral composition and dephytinization by wheat phytase will be discussed. Biochemical data for purified and characterized phytases isolated from more than 23 plant species are presented, the dephosphorylation pathways of phytic acid by different classes of phytases are compared, and the application of phytase in food and feed is discussed.