Wheat flour iron (Fe) fortification is mandatory in 75 countries worldwide yet many Fe fortificants, such as Fe-ethylenediaminetetraacetate (EDTA), result in unwanted sensory properties and/or gastrointestinal dysfunction and dysbiosis. Nicotianamine (NA) is a natural chelator of Fe, zinc (Zn) and other metals in higher plants and NA-chelated Fe is highly bioavailable in vitro. In graminaceous plants NA serves as the biosynthetic precursor to 2′ -deoxymugineic acid (DMA), a related Fe chelator and enhancer of Fe bioavailability, and increased NA/DMA biosynthesis has proved an effective Fe biofortification strategy in several cereal crops. Here we utilized the chicken (Gallus gallus) model to investigate impacts of NA-chelated Fe on Fe status and gastrointestinal health when delivered to chickens through intraamniotic administration (short-term exposure) or over a period of six weeks as part of a biofortified wheat diet containing increased NA, Fe, Zn and DMA (long-term exposure). Striking similarities in host Fe status, intestinal functionality and gut microbiome were observed between the short-term and long-term treatments, suggesting that the effects were largely if not entirely due to consumption of NA-chelated Fe. These results provide strong support for wheat with increased NA-chelated Fe as an effective biofortification strategy and uncover novel impacts of NA-chelated Fe on gastrointestinal health and functionality.
Bibliographical noteFunding Information:
This work was supported by grants from the HarvestPlus Challenge program to A.A.T.J. We thank Adrian Cox, Leigh Smith, Shahajahan Miyan and Ed Barrett‐Lennard at the Department of Primary Industries and Regional Development Western Australia (Western Australia, Australia) and Marcus Newberry and Crispin Howitt at The Commonwealth Scientific and Industrial Research Organisation (CSIRO, Canberra, Australia) for excellent technical assistance related to field trial and grain milling components of our research. We also thank Mary Bodis, Yongpei Chang and Shree Giri for invaluable help provided throughout the project. Analysis of NA and DMA was carried out at Metabolomics Australia (School of BioSciences, The University of Melbourne, Australia), an NCRIS initiative under Bioplatforms Australia Pty Ltd. The authors wish to dedicate this manuscript in memory of Adrian Cox.
© 2020, The Author(s).