Alternative Iron Source Research Articles

Treatment of textile dyes with steel flakes via Fenton and Electro-Fenton processes: An experimental analysis

The textile production process is well recognised as one of the most water-intensive industries, with an estimated daily water consumption of several thousand cubic metres. The main objective of the study is to remove the colour and COD of three reactive dyes namely reactive blue, reactive yellow and reactive black by Fenton and Electro Fenton Process. In this research paper, new novel catalyst steel flakes have been employed as part of the Fenton and Electro-Fenton process, replacing the conventional Fenton and Electro-Fenton catalyst. Scanning Electron Microscope (SEM), Energy-Dispersive X-ray Analysis (EDAX), Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and Thermo Gravimetric Analysis (TGA) was done to characterize the steel flakes. The pH, dye concentration, FeSO4 dosage and H2O2 dosage were studied. The maximum colour and Chemical Oxygen Demand (COD) removal in Fenton process was 98.47 % and 74 % respectively. In Electro Fenton Oxidation the maximum colour and COD removal was 99.65 % and 78 % respectively. The best colour and COD removal was observed by Fenton and Electro Fenton oxidation with optimum Fenton molar ratio of 50:1 and pH 3 in all three dyes. In the laboratory-scale feasibility tests on the Electro-Fenton process, the highest colour removal effectiveness was observed at catalyst dosages of 1 g/L, 132 mM H2O2, and pH 3. The novel modified heterogeneous Electro-Fenton approach presents a distinct cost-effectiveness benefit in comparison to both the conventional Electro-Fenton reaction and the Electro-Fenton reaction employing alternative iron sources.

A Robust Static Model of Basic Oxygen Furnace for Analyzing Emerging Steelmaking Scenarios

A robust static model, which incorporates emerging steelmaking scenarios in terms of solid charge mix with the given hot metal in basic oxygen furnace process, is developed. It employs mass and enthalpy balances to comprehend nonequilibrium conditions, considering four key empirical parameters: iron loss, post‐combustion ratio, heat loss, and undissolved lime content in slag, which are fine‐tuned using plant data through a multivariate approach, ensuring the reliability. The model is validated in a basic oxygen furnace (BOF) shop using data from over 4000 heats, achieving a strike rate of ≈77% for input lime prediction within ±1 ton and ≈80% for input oxygen prediction within ±600 Nm3. Model implementation in BOF shop provides valuable guidance to the operators, resulting in the reduction of average oxygen and lime consumption by 139 Nm3 and 652 kg heat−1, respectively. The model also enables the determination of the maximum scrap utilization of ≈16% for 0.8% silicon and ≈14% for 0.6% silicon in hot metal, respectively. The model aids in calculating the maximum tap temperature for varying hot metal silicon and iron ore addition. Overall, the model optimizes primary steelmaking, enhancing efficiency, reducing resource consumption, and offering insights into alternative iron sources like direct reduced iron.

Quality of edible bird’s nest treated by keratinolytic enzymes-based cleaning solution

Edible bird's nest (EBN) is one of the luxury foods that is widely used as a healthy food due to its nutritional value and therapeutic benefits. The traditional EBN washing process causes a reduction in weight and nutrient content and an increase in pollutants due to the use of hydrogen peroxide. An exploratory observation method was used to examine the quality of EBN from Collocalia fuciphaga before and after washing using a washing solution based on keratinolytic enzymes. There are four stages of EBN cleaning i.e. cleaning by tap water, ethanol solution, enzyme solution at room temperature and 50oC and drying at 40oC for 42 hrs. A total of 60 EBN (unclean, n = 30) and clean, n = 30) were analyzed using the AOAC method. The mineral content of Ca, Fe, K and Mg using atomic absorption spectrophotometry (AAS) except that P was measured by spectrophotometer. A carbohydrate estimation kit was used to measure glycoprotein content and the amino acid content was determined using the HPLC method. Evaluation of the cleanliness was carried out using a scoring system by semi-trained panelists. The results obtained showed that the clean EBNs were slightly yellowish-white in color, and the cleanliness of EBN before and after cleaning increased from 2.35 to 3.84. Clean EBN protein content decreased by 7.2% while total amino acids decreased from 38.51% to 32.71%. Clean EBN contains eight essential amino acids of 17.93% with high levels of leucine, valine, arginine, and threonine (2.42-2.96%). EBN's clean ash content increased from 3.7% to 7.8%. Carbohydrate content and iron in clean EBN were 39.19±0.76% and 14.35 mg/100 g dry matter, respectively. The high levels of carbohydrates and iron appear to be good sources of glycoprotein to support health and have the potential as an alternative source of iron for people with anemia. The stepwise EBN washing method using tapwater, ethanol and a washing solution based on keratinolytic enzymes can be applied to reduce weight loss and improve the quality of EBN.

The effect of iron absorption in ferrous gluconate form from enriched rice flour using an in vitro digestion model and a Caco-2 cell model.

Iron deficiency can cause serious diseases in infants and young children such as indigestion, anemia, and nervous system dysplasia. Consumption of high-iron rice flour can prevent iron deficiency. The objective of this study was to evaluate the potential application of ferrous gluconate as an iron source in high-iron rice flour used as a type of accessory food for infants and young children. In this study, the differences in iron absorption ability between ferrous gluconate and ferrous fumarate in rice flour with the same ingredients in both high and low phytic acid systems were evaluated. The results showed that there was no significant difference in the bioaccessibility/bioavailability between ferrous gluconate and ferrous fumarate at both low and high phytic acid contents. In low phytic acid and high phytic acid systems, the iron absorption rate of ferrous gluconate is 11.53% and 13.45% higher than that of ferrous fumarate, respectively (p < 0.05). In summary, the iron absorption rate of ferrous gluconate was higher than that of ferrous fumarate in the rice flour system. Additionally, the low phytic acid environment is more conducive to iron uptake and utilization. Therefore, ferrous gluconate can be used as an alternative source of iron in accessory foods for infants and young children.

An overview of the most actual methods of pyrite ash valorization

The obtaining process of sulfuric acid, that involves roasted of pyrite ores, leads to accumulation of a significant amount of secondary matter known as pyrite ash. This waste, that is found worldwide in quantities of millions of tons, it is highlighted by his chemical composition, based on the presence of high concentrations of hematite and magnetite. By implementing worldwide of the concept of circular economy, the use of pyritic ash as an alternative source of iron is a topic of current interest. This study is proposing to present the latest trends in the methods of valorization of pyritic ash that are presented in the specialty literature, which can be implemented in various branches of industry.

The effect of dechitinization on iron absorption from mealworm larvae (Tenebrio molitor) flour added to maize meals: stable-isotope studies in young females with low iron stores

Edible insects have a low ecological footprint and could serve as an alternative dietary iron source. However, chitin, a major component of insects, avidly binds iron and might inhibit iron absorption. We aimed to measure fractional iron absorption (FIA) from Tenebrio molitor-based test meals with and without dechitinization, and to assess the effect of native and low chitin T. molitor on FIA from iron-fortified maize porridge. We measured iron absorption in young females with low iron stores (n=21) from 1) labeled (54FeSO4) fortified maize porridge (maize alone); 2) intrinsically labeled (57Fe added during rearing) T. molitor larvae with native chitin content (NC) added to maize alone; and 3) dechitinized intrinsically labeled (57Fe) T. molitor larvae with low chitin content (LC) added to maize alone. We determined FIA using erythrocyte isotope incorporation and measured in vitro iron dialyzability from the 3 meals. NC and LC T. molitor had similar mean±SD iron content (12.0±0.1mg/100g). Geometric mean (95% CI) FIAs from the 3 test meals were 1) maize alone: 5.8% (3.2%, 10.8%); 2) maize+NC T. molitor: 5.3% (2.5%, 11.3%) and 4.1% (1.9%, 8.7%); and 3) maize+LC T. molitor: 4.6% (2.0%, 10.3%) and 4.0% (1.8%, 9.2%), for extrinsic and intrinsic labels, respectively. FIA from NC and LC T. molitor did not significantly differ, and both were lower (P<0.005) than FIA from the labeled maize porridge in the 3 meals, which did not significantly differ. The slopes of the relations between FIA and serum ferritin in the different meals and from the intrinsic and extrinsic labels did not significantly differ. T. molitor biomass does not strongly affect iron absorption when added to maize porridge. Our data suggest T. molitor iron is absorbed from the common nonheme iron pool. Native T. molitor is high in iron which is moderately well absorbed, suggesting it could be a valuable dietary iron source.This trial was registered at clinicaltrials.gov as NCT04510831.

A pseudokinase version of the histidine kinase ChrS promotes high heme tolerance of Corynebacterium glutamicum.

Heme is an essential cofactor for almost all living cells by acting as prosthetic group for various proteins or serving as alternative iron source. However, elevated levels are highly toxic for cells. Several corynebacterial species employ two paralogous, heme-responsive two-component systems (TCS), ChrSA and HrrSA, to cope with heme stress and to maintain intracellular heme homeostasis. Significant cross-talk at the level of phosphorylation between these systems was previously demonstrated. In this study, we have performed a laboratory evolution experiment to adapt Corynebacterium glutamicum to increasing heme levels. Isolated strains showed a highly increased tolerance to heme growing at concentrations of up to 100 μM. The strain featuring the highest heme tolerance harbored a frameshift mutation in the catalytical and ATPase-domain (CA-domain) of the chrS gene, converting it into a catalytically-inactive pseudokinase (ChrS_CA-fs). Reintroduction of the respective mutation in the parental C. glutamicum strain confirmed high heme tolerance and showed a drastic upregulation of hrtBA encoding a heme export system, conserved in Firmicutes and Actinobacteria. The strain encoding the ChrS pseudokinase variant showed significantly higher heme tolerance than a strain lacking chrS. Mutational analysis revealed that induction of hrtBA in the evolved strain is solely mediated via the cross-phosphorylation of the response regulator (RR) ChrA by the kinase HrrS and BACTH assays revealed the formation of heterodimers between HrrS and ChrS. Overall, our results emphasize an important role of the ChrS pseudokinase in high heme tolerance of the evolved C. glutamicum and demonstrate the promiscuity in heme-dependent signaling of the paralogous two-component systems facilitating fast adaptation to changing environmental conditions.

Effects of Dietary Iron Quantities and Sources on Lymantria dispar (Lepidoptera: Erebidae) Survival and Development.

Lymantria dispar L. is a serious invasive defoliator of broadleaf trees in both North America and Eurasia. When rearing L. dispar for research, the artificial diet must have a source of iron that is bioavailable and in the quantity needed to ensure normal development and survival. The standard iron supplement in L. dispar diet, amorphous ferric phosphate, is no longer commercially available, which motivated studies on alternative iron sources and concentrations. The responses of three L. dispar populations (including an L. dispar asiatica Vnukovskij population) to seven different iron doses were determined over two generations. The response to eight iron compounds and no added iron was also assessed over two generations for an L. dispar dispar population. The optimal levels of iron were 100, 150, and 198 mg/l of available iron for the New Jersey Standard Strain, a near-wild West Virginia population, and a near-wild Russian Far East population, respectively. All three populations showed symptoms of insufficient iron when reared on the lowest dose of iron and signs of excess iron at the highest two doses. All of the alternate iron sources evaluated provided adequate available iron, although three sources had some issues that may not make them the best options. These results reveal differences in nutritional requirements among different populations of L. dispar and verify the existence of viable replacement sources of iron for the standard amorphous ferric phosphate long used in L. dispar rearing.

Insights into the formation mechanism of hard sludge on the secondary side of PWR steam generators

• Mixtures of alumina, silica and magnetite have been aged in hydrothermal conditions. • Kaolinite has been identified as a cement binding the magnetite particles. • In presence of metallic iron, iron silicate precipitates. In the secondary circuit of nuclear Pressurized Water Reactors, corrosion products and impurities lead to the formation of undesirable hard deposits, called hard sludge, on the tube sheet of steam generators. Theses deposits are mainly composed of iron (magnetite), alumina and silica. The formation of hard sludge piles is investigated by reproducing the reaction of precursor oxides in the conditions of the steam generator (275 °C, 58 bar). Mixtures of magnetite, γ-alumina and amorphous silica in binary or ternary systems in an alkaline ethanolamine-ammonia solution at pH 25°C = 9.6 are studied. Carbon steel was tested as an alternative source of iron. The analysis of the evolution of the suspensions, completed by the industrial feedback, allows to explain the process of hard sludge formation in the steam generators. The following sequence is proposed: sedimentation of magnetite/confinement of the interstitial fluid/concentration of aqueous species such as aqueous silica and alumina/sorption of Al on magnetite and/or growth of boehmite/reaction with aqueous silica to form kaolinite as a resistant cement. Once formed, the kaolinite cement tends to densify over time while magnetite is passive. The absence of Fe-phyllosilicates predicted by thermodynamics is explained by the low solubility of magnetite making unfavorable the precipitation of Fe-silicate. By contrast, metallic iron is not stable at contact with water and the continual production of divalent iron, whose solubility is much higher than that of magnetite, allows to overpass a threshold concentration what makes possible the precipitation of a berthierine layer at the surface of corroded steel. This layer constitutes the nucleation site for the further precipitation of other aluminosilicates.

Effect of temperature on the slag/refractory interfacial reaction with directed reduced iron (DRI) addition in an electric arc furnace (EAF) process: Diffusional growth of magnesiowüstite layer by Boltzmann-Matano analysis

This study investigated the effect of temperature (1550–1650 °C) on the electric arc furnace (EAF) slag and magnesia refractory interfacial reaction with 20% direct reduced iron (DRI) addition as an alternative iron source in an Ar atmosphere. Variations in MgO content from initial to final stage were proportional to the temperature, indicating that MgO degradation by molten EAF slag was affected by the concentration gradient between initial and saturation conditions depending on temperature. In addition, the temperature affected MgO content more dominantly than DRI did. In other words, temperature control in an EAF process using DRI is relatively more important than the control of DRI itself for preventing MgO refractory degradation. The magnesiowüstite (MW) intermediate layer thickness and MgO refractory dissolution depth increased as the temperature increased because MgO solubility in molten EAF slag is proportional to temperature. Finally, the inter-diffusivity (D˜Fe−Mg, m2/s), which was estimated by Boltzmann-Matano analysis, ranged D˜Fe−Mg=10−12.0−10−12.5 and logD˜Fe−Mg generally decreased with decreasing temperature. The activation energy was found to be approximately 240 kJ/mol. Therefore, it can be concluded that suitable control of temperature in an EAF process using DRI is important to minimize refractory degradation.

Pemanfaatan Tepung Kelakai Sebagai Bahan Pangan Alternatif Sumber Zat Besi Dalam Subtitusi Produk Cookies Chickpea Untuk Ibu Hamil Anemia

The prevalence of anemia in pregnant women in Indonesia increased significantly from 37.1% in 2013 to 48.9% in 2018. Anemia can be prevented and treated by consuming iron source foods. The purpose of this research is to utilize kelakai flour as an alternative food source of iron in the substitution of chickpea cookies products for pregnant women with anemia. The study used a Complete Randomized Design (RAL) consisting of three levels of treatment and two repetitions, namely: Comparison of chickpea flour and kelakai flour F1 (30g : 15g), F2 (27.5g: 17.5), F3 (25g : 20g). Analysis of organoleptic test data and chemical properties analysis used Kruskall Wallis test and ANOVA test. The results showed that in organoleptic testing substitution of kelakai flour had a real effect (p<0.05) on taste and aroma parameters. The result of substitution kelakai flour had a real effect (p<0.05) on ash, protein and iron content of cookies. Cookies F3 is the best formulation that had a chemical composition; 463.02 kcal of energy, 17.18% fat, 10.23% protein, 66.87% carbohydrates, 6.97mg of iron. The iron content of cookies F3 has qualified the claim of iron source of food products required by BPOM.

Novel Foods and Sustainability as Means to Counteract Malnutrition in Madagascar

Although the trends of international reports show an increase in overweight and obesity, even in developing countries, there are still areas of the world, such as Sub-Saharan Africa, strongly affected by undernutrition. Specifically, in Madagascar, the percentage of stunted children under 5 is extremely high. Furthermore, the COVID-19 pandemic is expected to increase the risk of all forms of malnutrition, especially in low-income countries, including Madagascar, with serious intergenerational repercussions. This narrative review aims at investigating eating habits and cooking methods of the Malagasy population, addressing sustainable healthy diets through promotion of novel foods. While novel foods are a recent concept, there are data that describe how they may contribute to counteract food insecurity and malnutrition considering context and place. Efforts to promote native, traditional foods as Moringa oleifera, an indigenous plant in Asia and Africa including Madagascar, rich in protein and micronutrients, as well as edible insects, alternative sustainable source of protein, lipids, iron, and zinc, would provide not only nutritional but also cultural and economic benefits. The potential synergies between food traditions and agroecology have the potential to impact health addressing larger issues of sustainability and food security. Regional, national, and international policies are needed to develop and support one health approach actions.

Mineralogical Characterization-Assisted Reduction Roasting of Banded Hematite Jasper Ore

In many parts of India, because of depletion in high grade iron ore, efforts are focused on the use of low-grade iron ore for steel production. As an alternative iron source, low-grade banded iron ores have attracted attention. The beneficiation and utilization of banded iron ore is closely connected to their mineralogical characteristics, nature of impurity inclusion and liberation behavior. Characterization studies indicated that ore was low in iron value (~ 36.5 wt%), and contained high amount of silica (~ 46.3 wt%), which made it difficult to process by conventional beneficiation method. Therefore, we used reduction roasting method on the ore to produce the pellet feed material. Different process parameters such as roasting time, temperature and coal-ore ratio were optimized to achieve the maximum recovery and grade of magnetic product. Using coal as reducing agent, the optimum condition was found to be as, reduction temperature: 900 °C, time: 90 min, and coal-ore ratio: 15%. Under the optimum condition, maximum recovery and grade of magnetic product were found to be 72% and 65%, respectively.

Evaluation and comparison of Fenton-like oxidation with Fenton’s oxidation for hazardous methoxyanilines in aqueous solution

Methoxyanilines are aniline derivatives that are important chemical precursors for numerous Dye and Pharmaceuticals industries. Wastewater containing methoxyanilines have high toxicity and carcinogenic properties and if discharged without prior treatment into fresh water resources, can result in possible detrimental eff ;ects to aquatic life and public health. Therefore, in this work Fenton-like oxidation was evaluated for the degradation of 2-methoxyaniline (2-MA) and 4-methoxyaniline (4-MA) separately using abundantly available Laterite soil as an alternative source of iron against commercially procured iron (CI) in Fenton-oxidation. Parameters like hydrogen peroxide (H2O2), iron and initial methoxyanilines concentration were investigated for each of the methoxyanilines in separate experiments. For initial methoxyanilines concentration of 0.5mM, the maximum methoxyanilines removal of 83.28±0.26% and 86.34±0.34% and COD removal of 71.91±0.31% and 72.64±0.29% for 2-MA and 4-MA at pH 3 and pH 2.5 was attained at laterite soil iron [LSI] of 0.05mM respectively. From kinetic studies of 2-MA and 4-MA, reaction time was estimated to be 360min. Degradation with LSI was found to be slower and lesser than CI, but is comparable and can be applied as a replacement of CI for treatment of wastewater containing toxic and incalcitrant chemicals.

Nitrate Reduction of the Siilinjärvi/Finland Mine Water with Zero-valent Iron and Iron Waste as Alternative Iron Sources

Nitrate reduction was optimized in water from the Siilinjarvi/Finland mine site with iron powder and iron nanoparticles. Iron waste from a mold machining industry was then tested as a potential alternative. Complete reduction of nitrate from the mine water was achieved with the iron powder and nanoparticles at pH 2. The iron waste, though less efficient, still achieved 53% nitrate reduction. Examination of the surface of the iron powder and waste by SEM–EDS showed iron corrosion: crystals of iron oxides grew on the iron surface as the pH increased during NO3− reduction, until about pH 5. The major by-product of the NO3− reduction of mine water was NH4+, with low NO2− concentrations (< 7%). Although iron powder and nanoparticles were more reactive, the iron waste results are promising. Despite its low BET surface area, the use of iron waste to treat high volumes of mine water would appear to have economical and sustainable advantages. More efficient NO3− reduction could possibly be attained with iron waste of higher BET surface area and/or by combining it with other chemical treatments.

Potential applications of ASR fly ash in photo-Fenton like process for the degradation of tetracycline at neutral pH: Fixed-bed approach

The current research work investigated the effective utilization of automobile shredder residue (ASR) fly ash as an alternative iron source to degrade recalcitrant organic pollutants like tetracycline (TC) via a visible-light-driven photo-Fenton-like process at neutral pH. The whole photodegradation process was carried out in a fixed mode by using highly durable ASR fly ash beads as the catalyst in the photo-Fenton reaction. As confirmed through several characterization techniques, these beads contained hematite, goethite, magnetite, pyrite and wustite forms of iron oxides. Moreover, iron cations (Fe2+ and Fe3+) had leached out from the ASR fly ash beads during the reaction, which further promoted the photo-Fenton process. The detailed mechanism for the photodegradation of TC using ASR fly ash beads was studied. The high photodegradation efficiency of TC after 3 h of natural solar irradiation further confirmed the real-time applications of ASR fly ash in wastewater treatment. The ASR fly ash beads remained active and stable even after 10 recycling tests, as cross confirmed through characterization tests. Therefore, the obtained results clearly indicated that the use of ASR fly ash in wastewater treatment can add value to waste while providing a low cost and sustainable solution to various industries.

Fractional Absorption of Iron from Crickets Consumed with Refined or Whole Meal Maize Porridge in Young Adult Women (OR07-06-19)

ObjectivesEdible insects are considered as an alternative source of proteins, but in addition are also rich sources of minerals. However, no studies have investigated the bioavailability of minerals from edible insects in humans. House cricket (Acheta domesticus) is an edible insect species that is commonly consumed in low and middle income countries where the prevalence of iron deficiency and anaemia is relatively high. We aimed to assess the fractional iron absorption of iron from house crickets in humans after addition to either a refined (low-phytate) or a whole meal (high-phytate) maize porridge meal. A second objective was to assess the fractional iron absorption from maize porridge meals when crickets were added. MethodsA single blind randomized cross-over trial was conducted. We recruited 24 females (18–30 years) with serum ferritin < 25 ng/mL and body weight < 65 kg. Six different meals with equivalent amounts of iron were randomly administered to each participant in two series, consisting of either refined (low-phytate) or whole meal (high-phytate) maize porridge with A) intrinsically 57Fe labelled house crickets; B) 58FeSO4; and C) unlabelled house crickets and 54FeSO4. Fractional iron absorption was determined by measuring shifts in Fe isotope ratios incorporated into erythrocytes that were collected before and 14 days after administration of each series of experimental meals. ResultsFor refined maize porridge, mean fractional absorption of iron from meal B was higher (13.55%; P < 0.001) than from meals A (1.99%) and C (3.12%). As expected, iron absorption was significantly lower from meals prepared from whole meal maize flour as compared to those prepared from refined flour (P < 0.001). For whole meal maize porridge, fractional absorption of iron from meals A, B and C was 1.31%, 3.12% and 2.30%, respectively. ConclusionsFractional absorption of iron from edible house crickets added to maize porridge was generally low, and addition of crickets to refined maize porridge reduced fractional iron absorption from the meal. Before promoting edible insects as an alternative source of iron, further investigation into their anti-nutritional properties is required. Funding SourcesWellcome Trust, UK.

Acid mine drainage sludge as an alternative raw material for M-type hexaferrite preparation

Two types of dewatered acid mine drainage sludge were sampled from abandoned Japanese mines. The sludge shows great potential to be completely reused as alternative iron and calcium sources to synthesize M-type calcium substituted barium hexaferrite with addition of BaCO3 by solid-state reaction. The precursors and as-prepared samples were investigated by X-ray diffraction (XRD), field-emission scanning electron microscopy, and thermogravimetry–mass spectroscopy. The effect of sludge addition on phase formation and microstructure evolution during calcination was discussed in details. For sludge content up to 93.9 mass % with addition of 6.1 mass % BaCO3, M-type hexaferrite can be identified in the XRD patterns of as-prepared samples calcined at 1100, 1200, and 1300 °C. The impurities in the sludge, such as silicon, and aluminum, result in formation of secondary aluminosilicates phases; another impurity sulfur in the sludge may increase M-type hexaferrite formation temperature owing to barium or calcium sulfate formation in the precursor. The impurities also contribute to the difference in the microstructure for lower melting point. Possible applications of the sludge-derived hexaferrite products such as magnetic material or microwave absorber are suggested.

Toxic but tasty - temporal dynamics and network architecture of heme-responsive two-component signaling in Corynebacterium glutamicum.

SummaryHeme is an essential cofactor and alternative iron source for almost all bacterial species but may cause severe toxicity upon elevated levels and consequently, regulatory mechanisms coordinating heme homeostasis represent an important fitness trait. A remarkable scenario is found in several corynebacterial species, e.g. Corynebacterium glutamicum and Corynebacterium diphtheriae, which dedicate two paralogous, heme‐responsive two‐component systems, HrrSA and ChrSA, to cope with the Janus nature of heme. Here, we combined experimental reporter profiling with a quantitative mathematical model to understand how this particular regulatory network architecture shapes the dynamic response to heme. Our data revealed an instantaneous activation of the detoxification response (hrtBA) upon stimulus perception and we found that kinase activity of both kinases contribute to this fast onset. Furthermore, instant deactivation of the PhrtBA promoter is achieved by a strong ChrS phosphatase activity upon stimulus decline. While the activation of detoxification response is uncoupled from further factors, heme utilization is additionally governed by the global iron regulator DtxR integrating information on iron availability into the regulatory network. Altogether, our data provide comprehensive insights how TCS cross‐regulation and network hierarchy shape the temporal dynamics of detoxification (hrtBA) and utilization (hmuO) as part of a global homeostatic response to heme.

A novel nano-iron supplement to safely combat iron deficiency and anaemia in young children: The IHAT-GUT double-blind, randomised, placebo-controlled trial protocol

Background: Iron deficiency and its associated anaemia (IDA) are the leading forms of micronutrient malnutrition worldwide. Conventional oral iron supplements have limited efficacy and have been associated with increased infection, diarrhoea, and detrimental changes to the gut microbiome, particularly in young children. Here we describe the rationale and design of the first clinical trial evaluating the efficacy and safety of a novel nano iron supplement, iron hydroxide adipate tartrate (IHAT), for the treatment of IDA in young children (IHAT-GUT trial).Methods:IHAT-GUT is a three-arm, double-blind, randomised, placebo-controlled trial conducted in Gambian children 6-35 months of age. The intervention consists of a 12-week supplementation with either IHAT, ferrous sulphate (both at doses bioequivalent to 12.5 mgFe/day) or placebo. Assessments are conducted at baseline, Day 15, and Day 85 of the supplementation period. The trial aims to include 600 children with IDA who will be randomly assigned (1:1:1) to each arm. The primary objectives are to test non-inferiority of IHAT in relation to ferrous sulphate at treating IDA, and to test superiority of IHAT in relation to ferrous sulphate and non-inferiority in relation to placebo in terms of diarrhoea incidence and prevalence. Secondary objectives are to test whether IHAT reduces the burden of enteric pathogens, morbidity, and intestinal inflammation, and that it does not cause detrimental changes to the gut microbiome, particularly in relation toLactobacillaceae,BifidobacteriaceaeandEnterobacteriaceae.Discussion:This trial will test the hypothesis that supplementation with IHAT eliminates iron deficiency and improves haemoglobin levels without inducing gastrointestinal adverse effects. If shown to be the case, this would open the possibility for further testing and use of IHAT as an alternative iron source for micronutrient intervention strategies in resource-poor countries, with the ultimate aim to help reduce the IDA global burden.Registration:This trial is registered at clinicaltrials.gov (NCT02941081).