In the dissertation, we have been determining Fe concentration in grain of various sorts of wheat, its places of accumulation, and its binding forms. We have been determining the Fe concentrations with Standard Energy-Dispersive X-ray Fluorescence Spectrometry, the localization of Fe on tissue level of grain with Micro X-ray Absorption Spectroscopy and Fe binding forms in the whole grain and in separate tissues with Micro- X-ray Fluorescence Spectroscopy. As expected, various sorts differed in Fe content, with the sort »Super žitarka« containing the most Fe. Fe compounds that have corresponded to our measured spectres have been the same in all sorts: Fe2+ phytate, Fe3+ phytate and Fe3+ citrate. Their shares have also been comparable in all sorts, with the exception of the sort »Katrina« that contained more Fe2+ phytate and less Fe3+ citrate than other sorts, which shows inferior bioaccessibility of Fe in the said sort. The tissues most rich in Fe are the pericarp, nucleus and alveron. The pericarp does not contain Fe3+ phytate, which effects the greater bioaccessibility of Fe. The embryo also stands out with the increased content of Fe3+ citrate according to the Fe3+ phytate in comparison with the other tissues. For biofortification, it would be particularly necessary to use wheat bran that are rich in Fe and are lost in the processing.
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