Hadi Alkarawi H, Zotz G
Functional Ecology Group, Institute of Biology and Environmental Sciences, University of Oldenburg, Oldenburg, Germany; Foundation of Technical Education, Al-Musaib Technical College, Babylon, Iraq.
Plant Biol (Stuttg). 2014 Jul;16(4):697-701. doi: 10.1111/plb.12136. Epub 2013 Dec 16.
Phytic acid or phytate, the free-acid form of myo-inositolhexakiphosphate, is abundant in many seeds and fruits, where it represents the major storage form of phosphorus. Although also known from other plant tissues, available reports on the occurrence of phytic acid, e.g. in leaves, have never been compiled, nor have they been critically reviewed. We found 45 published studies with information on phytic acid content in leaves. Phytic acid was almost always detected when studies specifically tried to detect it, and accounted for up to 98% of total P. However, we argue that such extreme values, which rival findings from storage organs, are dubious and probably result from measurement errors. Excluding these high values from further quantitative analysis, foliar phytic acid-P averaged 2.3 mg·g(-1) , and represented, on average, 7.6% of total P. Remarkably, the ratio of phytic acid-P to total P did not increase with total P, we even detected a negative correlation of the two variables within one species, Manihot esculenta. This enigmatic finding warrants further attention.
植酸或肌醇六磷酸的游离酸形式，在许多种子和果实中含量丰富，是磷的主要储存形式。虽然在其他植物组织中也有发现，但关于植酸在例如叶片中的存在情况，尚无已发表的报告进行汇总，也未经过严格审查。我们找到了45项已发表的关于叶片中植酸含量的研究。当研究专门试图检测植酸时，几乎总能检测到，其含量占总磷的比例高达98%。然而，我们认为这些与储存器官的研究结果相当的极端值是可疑的，可能是测量误差导致的。在进一步的定量分析中排除这些高值后，叶片中植酸磷的平均含量为2.3毫克·克⁻¹，平均占总磷的7.6%。值得注意的是，植酸磷与总磷的比例并未随总磷含量增加，我们甚至在一种植物木薯中检测到这两个变量之间存在负相关。这一神秘的发现值得进一步关注。
