Fe In Wheat Research Articles

Global analysis of nitrogen fertilization effects on grain zinc and iron of major cereal crops.

Human zinc (Zn) and iron (Fe) deficiencies can partly be alleviated by enhancing cereal concentrations of these micronutrients. Soil nitrogen (N) levels codetermine cereal grain yields and Zn and Fe nutrition of plants and grains. Grain Zn and Fe concentrations have been reported to be affected by both yield dilution and enhanced acquisition and grain allocation of Zn and Fe. A global meta-analysis of 100 publications concerning wheat, maize, and rice providing 785 records of Zn and 506 records of Fe allowed us to assess their relative importance and quantify the concentrations and bioavailability of Zn and Fe in major cereal grains over a wide range of N fertilization levels. Compared with the no N controls, N application significantly increased grain Zn and Fe concentrations in all crops except maize Zn. The increase in grain protein concentration correlated positively with the increases in Zn and Fe concentrations in all cereals except Zn in maize. In rice, the grain Zn and Fe concentration increase was independent of the rate of N applied. Grain concentrations of Zn and Fe in wheat and Fe in maize were positively correlated with N rate but were only higher than those in the controls above 40–60 kg N ha−1. At lower N rates, the dilution effect was thus stronger than the enhancement effect. N supply had a larger effect on Zn and Fe concentrations in loamy textured soils or at lower soil available N and phosphorus (P), or higher soil organic matter and available Zn contents or with P and Zn fertilization, but the effect sizes differed among crops. Reductions in phytic acid concentration after N fertilization occurred in wheat, potentially improving micronutrient bioavailability. Thus, our findings indicate that N fertilization could be managed in ways that simultaneously support high grain yields and enhance nutritional quality for major cereals.

Harnessing the Wild Relatives and Landraces for Fe and Zn Biofortification in Wheat through Genetic Interventions—A Review

Micronutrient deficiencies, particularly iron (Fe) and zinc (Zn), in human diets are affecting over three billion people globally, especially in developing nations where diet is cereal-based. Wheat is one of several important cereal crops that provide food calories to nearly one-third of the population of the world. However, the bioavailability of Zn and Fe in wheat is inherently low, especially under Zn deficient soils. Although various fortification approaches are available, biofortification, i.e., development of mineral-enriched cultivars, is an efficient and sustainable approach to alleviate malnutrition. There is enormous variability in Fe and Zn in wheat germplasm, especially in wild relatives, but this is not utilized to the full extent. Grain Fe and Zn are quantitatively inherited, but high-heritability and genetic correlation at multiple locations indicate the high stability of Fe and Zn in wheat. In the last decade, pre-breeding activities have explored the potential of wild relatives to develop Fe and Zn rich wheat varieties. Furthermore, recent advances in molecular biology have improved the understanding of the uptake, storage, and bioavailability of Fe and Zn. Various transportation proteins encoding genes like YSL 2, IRT 1, OsNAS 3, VIT 1, and VIT 2 have been identified for Fe and Zn uptake, transfer, and accumulation at different developing stages. Hence, the availability of major genomic regions for Fe and Zn content and genome editing technologies are likely to result in high-yielding Fe and Zn biofortified wheat varieties. This review covers the importance of wheat wild relatives for Fe and Zn biofortification, progress in genomics-assisted breeding, and transgenic breeding for improving Fe and Zn content in wheat.

Biofortification of Wheat with Iron

In various micronutrient-deficient countries, wheat is used as staple food, comprise more than 50% of the diet. Like many staple foods, wheat contain low concentration of iron (Fe). About two billion people globally have iron deficiency, especially in the regions where staple foods are based on cereal crops such as wheat. Because of high rate of Fe deficiency cases, increased Fe intake through staple food has become the main focused research area globally. As wheat is main source of protein and dietary energy for human beings, its potential to support reducing malnutrition related to Fe can be increased through producing genetically modified wheat varieties with high concentration of Fe. High Fe concentration in cereal crop is a major challenge. Even though during wheat is commonly fortify, promising and more long term solution is biofortification of wheat, which bases on the production of new wheat varieties with characteristically higher concentration of iron. Till now, may researches, which focused on increasing Fe in wheat, aimed at producing natural varieties in progenitor or related species. This review focused on the promising and sustainable approaching to maintain the improve concentration of iron in wheat.

Estimation of the Levels of Fe in Wheat and Maize Flour Milled using Commercial Milling Machine and A Home Blender

Milling devices are among the most commonly used in our indigenous markets and homes and variety of elements such as Cu, Ni, Zn, Pb, Ti, Co, Cr, Al, Si, and Fe are used in their manufacture and fabrication. Often times they are present as alloys. With prolonged processing, these metals are gradually introduced as contaminants in the food being processed. Wheat and maize were selected for this study due to their wide usage as sources of protein and carbohydrate in Nigeria and Africa in general. The samples were cleaned by picking out sand, stones and other impurities and ground using the commercial milling machine and a home blender and were digested with HNO3 and HClO4 in the ratio of 4:1 and analyzed using AAS. Average Fe concentration values for both wheat and maize samples milled with commercial milling machine is 13.53 mg/kg and 26.79 mg/kg respectively while samples milled with the home blender gave concentration values of 4.00 mg/kg and 2.64 mg/kg for wheat and maize respectively. The high concentration of Fe in ground maize and wheat milled using the commercial milling machine could be attributed to the abrasive friction of the grinding disc as the grains come in contact with it during grinding resulting in its chipping off into the milled sample. It is therefore recommended that the commercial milling machine be redesigned with the incorporation of a permanent magnet to minimize or totally eliminate the introduction of Fe fillings into the ground grains and other foodstuffs. Keywords: Commercial milling machine, wheat, maize, contaminants, home blender, grinding

A Critical Evaluation of Survey Results of Vitamin A and Fe Levels in the Mandatory Fortified Food Vehicles and Some Selected Processed Foods in Nigeria

ABSTRACT A nationwide survey was conducted to ascertain the levels of Vitamin A and Fe in wheat and maize flours, sugar and vegetable oils and some flour-based processed foods to assess compliance to the Nigerian Industrial Standard. Samples were collected from factories and markets in all the 36 states of the six geopolitical zones of the country; comprising 94 (vegetable oil), 42 (sugar), 95 (flour) and 62 (processed foods) and subjected to vitamin A and iron analyses using HPLC and AAS respectively. Using a 50% acceptable range of the specified minimum standards as basis for compliance, the results showed that only 14.9 – 20.2 % of the samples of vegetable oils analyzed fell within acceptable level (10,000-20,000 IU/kg) but there was no significant difference (p > 0.05) in the results obtained for the six zones. For sugar, only 11.9 – 16.7 % of the samples collected complied with the acceptable range of the standards (12,500 – 25,000 IU/kg) but this varied significantly (p > 0.05) with the zones. The levels of compliance for vitamin A and Fe in flours were found to be 12.2 – 33.3 % and 1.0 – 21.0 % respectively at the acceptable range of 15,000 – 30,000 IU/kg and 34.6 – 46.8 mg/kg, respectively. In all cases, the compliance levels at the 50% range were only marginally higher than at the 30% WHO acceptable range. For the levels of these micronutrients in the processed foods, the values obtained ranged between 5,139 – 7,687 IU/kg for vitamin A and 11.9 – 16.7 mg/kg for Fe. These results call for a critical and holistic review of the fortification strategy in Nigeria.

Improved nitrogen status enhances zinc and iron concentrations both in the whole grain and the endosperm fraction of wheat

This study was conducted to assess the role of increasing N supply in enrichment of whole grain and grain fractions, particularly the endosperm, with Zn and Fe in wheat. The endosperm is the most widely consumed part of wheat grain in many countries. Plants were grown in the greenhouse with different soil applications of N and Zn and with or without foliar Zn spray. Whole grain and grain fractions were analyzed for N, P, Zn and Fe. Increased N supply significantly enhanced the Zn and Fe concentrations in all grain fractions. In the case of high Zn supply, increasing N application enhanced the whole grain Zn concentration by up to 50% and the endosperm Zn by over 80%. Depending on foliar Zn supply, high N elevated the endosperm Fe concentration up to 100%. High N also generally decreased the P/Zn and P/Fe molar ratios in whole grain and endosperm. The results demonstrate that improved N nutrition, especially when combined with foliar Zn treatment, is effective in increasing Zn and Fe of the whole grain and particularly the endosperm fraction, at least in the greenhouse, and might be a promising strategy for tackling micronutrient deficiencies in countries where white flour is extensively consumed.

Effect of nitrogen on uptake, remobilization and partitioning of zinc and iron throughout the development of durum wheat

Deficiencies of zinc (Zn) and iron (Fe) are global nutritional problems and caused most often by their limited dietary intake. Increasing Zn and Fe concentrations of staple food crops such as wheat is therefore an important global challenge. This study investigated the effects of varied nitrogen (N) and Zn supply on the total uptake, remobilization and partitioning of Zn, Fe and N in durum wheat throughout its ontogenesis. Plants were grown under greenhouse conditions with high or low supply of N and Zn, and harvested at 8 different developmental stages for analysis of Zn, Fe and N in leaves, stems, husks and grains. The results obtained showed that the Zn and Fe uptake per plant was enhanced up to 4-fold by high N supply while the increases in plant growth by high N supply were much less. When both the Zn and N supplies were high, approximately 50% of grain Zn and 80% of grain Fe were provided by post-anthesis shoot uptake, indicating that the contribution of remobilization to grain accumulation was higher for Zn than for Fe. At the high N and Zn application, about 60% of Zn, but only 40% of Fe initially stored in vegetative parts were retranslocated to grains, and nearly 80% of total shoot Zn and 60% of total shoot Fe were harvested with grains. All these values were significantly lower at the low N treatment. Results indicate that N nutrition is a critical factor in both the acquisition and grain allocation of Zn and Fe in wheat.