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Iron is an essential mineral that supports biological functions like growth, oxygen transport, cellular function, and hormone synthesis. Insufficient dietary iron can lead to anemia and cause fatigue, cognitive impairment, and poor immune function. Animal-based foods provide heme iron, which is more bioavailable to humans, while plant-based foods typically contain less bioavailable non-heme iron. Edible insects vary in their iron content and may have heme or non-heme forms, depending on their diet. Edible insects have been proposed as a protein source that could address issues of food insecurity and malnutrition in low resource contexts; therefore, it is important to understand the bioavailability of iron from insect-based foods. In this study, we used Inductively Coupled Plasma and Mass Spectrometry (IPC-MS) and Caco-2 cell culture models to compare the soluble and bioavailable iron among five different lab-produced tempeh formulations featuring Tenebrio molitor (mealworm) with their non-fermented raw ingredient combinations. Finally, we compared the iron bioavailability of a mealworm tempeh with two sources of conventional beef (ground beef and sirloin steaks) and two commercially available plant-based meat alternatives. The results show that while plant-based meat alternatives had higher amounts of soluble iron, particularly in the Beyond Burger samples, the fermented mealworm-based tempeh had greater amounts of bioavailable iron than the other samples within the set. While all the samples presented varying degrees of iron bioavailability, all products within the sample set would be considered good sources of dietary iron. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate in vitro and in vivo iron bioavailability of biofortified cowpeas (Vigna unguiculata (L) Walp) (Aracê, Xiquexique and Tumucumaque), compared to a conventional cultivar (Pajeú). In vitro bioavailability was evaluated in Caco-2 cells. For the in vivo study, 40 male Wistar rats were induced to anemia during 21 days (depletion phase), then, in repletion phase (14 days), the animals received as iron source (12 ppm): ferrous sulfate; Pajeú; Xiquexique, Aracê; or Tumucumaque. Pajeú had higher levels of complexing compounds than the biofortified cultivars. In Caco-2 cells, the cellular iron uptake index was higher for biofortified cowpeas, particularly Tumucumaque. Concerning the in vivo study, Tumucumaque group had the best hemoglobin regeneration efficiency and relative biological value, and improved colon crypt size. Then, the iron bioavailability was higher in the biofortified cowpeas, especially Tumucumaque, possibly due to the lower content of mineral-complexing compounds and improvement of absorptive area. This work provides important information to support strategies to combat iron deficiency.

Some yellow-colored market classes of dry bean (Phaseolus vulgaris L.) are valued by consumers as an easy-to-digest, fast cooking alternative to darker colored red and black beans, which in comparison generally have longer cooking times and reduced iron bioavailability. There is evidence that the cooking time of yellow beans is linked to the dietary fiber content and may also contribute to nutrient digestibility and bioavailability. Therefore, 52 fast-, moderate-, and slow-cooking yellow beans with diverse iron bioavailability from five market classes (Amarillo, Canario, Green-yellow, Manteca, and Mayocoba) were selected for total dietary fiber (TDF) analysis. TDF was measured as insoluble (IDF) + soluble (SDF) + oligosaccharides (OLIGO) using method AOAC2011.25. Wide variations in the concentrations of IDF (16.0–23.1%), SDF (1.6–7.7%), OLIGO (1.5–3.4%), and TDF (20.6–31.3%) were detected among the yellow beans with various cooking times. Lower concentrations of IDF in yellow beans were associated with shorter cooking times and higher iron bioavailability. The larger sized Andean yellow beans had more SDF than Middle American. One Mayocoba breeding line from Puerto Rico, PR1146-124, had 42% less OLIGOs than average, and may be useful for breeding low-flatulence beans for consumer acceptability. Fast cooking yellow beans provide the same SDF and OLIGO concentrations as yellow beans with longer cooking times but have the added benefit of shorter cooking times (convenience) and provide more bioavailable iron after cooking.

Iron deficiency remains a public health challenge globally. Prebiotics have the potential to improve iron bioavailability by modulating intestinal bacterial population, increasing SCFA production, and stimulating expression of brush border membrane (BBM) iron transport proteins among iron-deficient populations. This study intended to investigate the potential effects of soluble extracts from the cotyledon and seed coat of three pea (Pisum sativum) varieties (CDC Striker, CDC Dakota, and CDC Meadow) on the expression of BBM iron-related proteins (DCYTB and DMT1) and populations of beneficial intestinal bacteria in vivo using the Gallus gallus model by oral gavage (one day old chicks) with 1 mL of 50 mg/mL pea soluble extract solutions. The seed coat treatment groups increased the relative abundance of Bifidobacterium compared to the cotyledon treatment groups, with CDC Dakota seed coat (dark brown pigmented) recording the highest relative abundance of Bifidobacterium. In contrast, CDC Striker Cotyledon (dark-green-pigmented) significantly increased the relative abundance of Lactobacillus (p < 0.05). Subsequently, the two dark-pigmented treatment groups (CDC Striker Cotyledon and CDC Dakota seed coats) recorded the highest expression of DCYTB. Our study suggests that soluble extracts from the pea seed coat and dark-pigmented pea cotyledon may improve iron bioavailability by affecting intestinal bacterial populations. [ABSTRACT FROM AUTHOR]

Dry bean is a nutrient-dense food targeted in biofortification programs to increase seed iron and zinc levels. The underlying assumption of breeding for higher mineral content is that enhanced iron and zinc levels will deliver health benefits to the consumers of these biofortified foods. This study characterized a diversity panel of 275 genotypes comprising the Yellow Bean Collection (YBC) for seed Fe and Zn concentration, Fe bioavailability (FeBio), and seed yield across 2 years in two field locations. The genetic architecture of each trait was elucidated via genome-wide association studies (GWAS) and the efficacy of genomic prediction (GP) was assessed. Moreover, 82 yellow breeding lines were evaluated for seed Fe and Zn concentrations as well as seed yield, serving as a prediction set for GP models. Large phenotypic variability was identified in all traits evaluated, and variations of up to 2.8 and 13.7-fold were observed for Fe concentration and FeBio, respectively. Prediction accuracies in the YBC ranged from a low of 0.12 for Fe concentration, to a high of 0.72 for FeBio, and an accuracy improvement of 0.03 was observed when a QTN, identified through GWAS, was used as a fixed effect for FeBio. This study provides evidence of the lack of correlation between FeBio estimated in vitro and Fe concentration and highlights the potential of GP in accurately predicting FeBio in yellow beans, offering a cost-effective alternative to the traditional assessment of using Caco2 cell methodologies. [ABSTRACT FROM AUTHOR]

A side effect of the raised consumption of Greek yogurt is the generation of massive amounts of yogurt acid whey (YAW). The dairy industry has tried several methods for handling these quantities, which constitute an environmental problem. Although the protein content of YAW is relatively low, given the huge amounts of produced YAW, the final protein amount in the produced YAW should not be underestimated. Taking into consideration the increased interest for bioactive peptides and the increased demand for dietary proteins, combined with protein and peptides content of YAW, efforts should be made toward reintroducing the latter in the food supply chain. In this context and in view of the prevalent dietary iron deficiency problem, the objective of the present study was the investigation of YAW fractions' effect on Fe bioavailability. With this purpose, an in vitro digest approach, following the INFOGEST protocol, was coupled with the Caco2 cell model. To evaluate whether YAW digest fractions exert positive, negative or neutral effect on Fe bioavailability, they were compared with the ones derived from milk, a well-studied food in this context. Milk and YAW showed the same effectiveness on both Fe bioavailability and the expression of relative genes (DCYTB , DMT1 , FPN1 , and HEPH). Focusing further on YAW fractions, by comparison with their blank digest control counterparts, it resulted that YAW 3- to 10-kDa digests fraction had a superior effect over the 0- to 3-kDa fraction on Fe-uptake, which was accompanied by a similar effect on the expression of Fe metabolism-related genes (DCYTB , FPN1 , and HEPH). Finally, although the 3- to 10-kDa fraction of bovine YAW digests resulted in a nonsignificant increased Fe uptake, compared with the ovine and caprine YAW, the expression of DCYTB and FPN1 genes underlined this difference by showing a similar pattern with statistically significant higher expression of bovine compared with ovine and bovine compared with both ovine and caprine, respectively. The present study deals with the novel concept that YAW may contain factors affecting Fe bioavailability. The results show that it does not exert any negative effect and support the extensive investigation for specific peptides with positive effect as well as that YAW proteins should be further assessed on the prospect that they can be used in human nutrition. [ABSTRACT FROM AUTHOR]

ABSTRACT Common bean (Phaseolus vulgaris L.) is a grain legume rich in proteins and micronutrients, particularly iron and zinc. In this study, 30 small‐seeded genotypes were planted in five locations in Ethiopia, following an alpha lattice design with three replications, to determine environmental and genotypic influence on the Fe and Zn concentration. Based on their Fe and Zn contents, bean cultivars were evaluated for adaptability and stability using AMMI analysis. The Fe concentrations of raw bean seed varied from 44.4 to 84.4 μg/g within the panel of small‐seeded genotypes, with an average range of variance of 18 μg/g across environments, and its seed Zn concentrations varied from 19.7 to 32.3 μg/g, with an average range of variance of 12.6 μg/g across environments. The averages bean Fe concentration among the small‐seeded genotypes across sites in Ethiopia was 62.2 and 26.1 μg/g for Zn concentrations. Results from the analysis of variance using the AMMI model indicated that genotypes accounted for 20.53% and 9.49% of the total variance in seed Fe and Zn concentrations, respectively. The environment had a greater impact, affecting 60.92% and 81.52% of total sum of squares for Fe and Zn concentrations, respectively. According to the broad‐sense heritability, there appears to be some genetic control over Fe and Zn concentrations. However, the substantial effects of the environment and genotype‐by‐environment interaction on Fe and Zn concentrations in small‐seeded genotypes indicates breeding for higher amounts of trace minerals in new bean varieties could be a challenging task. This means the notion that beans can be biofortified to have higher concentrations of Fe and Zn might not be achievable in Ethiopia. A shift in breeding strategies that focuses on traits to enhance the bioavailability of Fe and Zn from bean is warranted and could be a solution to enhance the delivery of iron from small‐seeded beans produced in Ethiopia.

Dry bean is a nutrient-dense food targeted in biofortification programs to increase seed iron and zinc levels. The underlying assumption of breeding for higher mineral content is that enhanced iron and zinc levels will deliver health benefits to the consumers of these biofortified foods. This study characterized a diversity panel of 275 genotypes comprising the Yellow Bean Collection (YBC) for seed Fe and Zn concentration, Fe bioavailability (FeBio), and seed yield across 2 years in two field locations. The genetic architecture of each trait was elucidated via genome-wide association studies (GWAS) and the efficacy of genomic prediction (GP) was assessed. Moreover, 82 yellow breeding lines were evaluated for seed Fe and Zn concentrations as well as seed yield, serving as a prediction set for GP models. Large phenotypic variability was identified in all traits evaluated, and variations of up to 2.8 and 13.7-fold were observed for Fe concentration and FeBio, respectively. Prediction accuracies in the YBC ranged from a low of 0.12 for Fe concentration, to a high of 0.72 for FeBio, and an accuracy improvement of 0.03 was observed when a QTN, identified through GWAS, was used as a fixed effect for FeBio. This study provides evidence of the lack of correlation between FeBio estimated in vitro and Fe concentration and highlights the potential of GP in accurately predicting FeBio in yellow beans, offering a cost-effective alternative to the traditional assessment of using Caco2 cell methodologies.

Iron is an important micronutrient required for a number of biological processes including oxygen transport, cellular respiration, the synthesis of nucleic acids and the activity of key enzymes. The World Health Organization has recognised iron deficiency as the most common nutritional deficiency globally and as a major determinant of anaemia. Iron deficiency anaemia affects 40% of all children between the ages of 6 and 59 months, 37% of mothers who are pregnant and 30% of women between the ages of 15 and 49 years worldwide. Dietary iron exists in two main forms known as haem iron and non‐haem iron. Haem iron is obtained from animal sources such as meat and shows higher bioavailability than non‐haem iron, which can be obtained from both plant and animal sources. Different components in food can enhance or inhibit iron absorption from the diet. Components such as meat proteins and organic acids increase iron absorption, while phytate, calcium and polyphenols reduce iron absorption. Iron levels in the body are tightly regulated since both iron overload and iron deficiency can exert harmful effects on human health. Iron is stored mainly as haemoglobin and as iron bound to proteins such as ferritin and hemosiderin. Iron deficiency affects individuals at increased risk due to factors such as age, pregnancy, menstruation and various diseases. Different solutions for iron deficiency are applied at individual and community levels. Iron supplements and intravenous iron can be used to treat individuals with iron deficiency, while various types of iron‐fortified foods and biofortified crops can be employed for larger communities. Foods such as rice, flour and biscuits have been used to prepare fortified iron products. However, it is important to ensure the fortification process does not exert significant negative effects on organoleptic properties and the shelf life of the food product. [ABSTRACT FROM AUTHOR]

Iron deficiency is a global nutritional problem, and adding iron salts directly to food will have certain side effects on the human body. Therefore, there is growing interest in food-grade iron delivery systems. This review provides an overview of iron delivery systems, with emphasis on the controlled release of iron during gastrointestinal digestion, as well as the enhancement of iron absorption and bioavailability. Iron-bearing proteins are easily degraded by digestive enzymes and absorbed through receptor-mediated endocytosis. Instead, protein aggregates are slowly degraded in the stomach, which delays iron release and serves as a potential iron supplement. Amino acids, peptides and polysaccharides can bind iron through iron binding sites, but the formed compounds are prone to dissociation in the stomach. Moreover, peptides and polysaccharides can deliver iron by mediating the formation of ferric oxyhydroxide which is absorbed through endocytosis or bivalent transporter 1. In addition, liposomes are unstable during gastric digestion and iron is released in large quantities. Complexes formed by polysaccharides and proteins, and microcapsules formed by polysaccharides can delay the release of iron in the gastric environment and prolong iron release in the intestinal environment. This review is conducive to the development of iron functional ingredients and dietary supplements. [ABSTRACT FROM AUTHOR]

Low bioavailability of the vital element iron (Fe) limits primary production in large regions of the Southern Ocean, thus impacting phytoplankton community structures. Primary productivity seems to be particularly sensitive to the reduced form of iron (Fe(II)), which is thought to be the most readily bioavailable redox form of Fe in the ocean. Here, we investigated the impact of temperature (3 °C, 5 °C and 7 °C) and Fe(II) additions (+ 5 nM) on growth of two Southern Ocean phytoplankton species Fragilariopsis cylindrus and Phaeocystis antarctica in coastal and open ocean water. At all tested temperatures, growth rates of P. antarctica were significantly higher with added iron, compared to the treatments without added iron in both waters. Temperature only had a significant effect on the growth rate of this species when it was raised to 7 °C in all treatments. For F. cylindrus, growth rates only significantly increased with iron addition at 7 °C in both water types. Temperature did not affect the growth rate of F. cylindrus except for a significant reduction without iron addition at 7 °C in coastal water. These results highlight the complex interactions between Fe bioavailability and temperature on Southern Ocean phytoplankton growth. Thus, certain Southern Ocean phytoplankton species may have higher growth rates in regions of the ocean that will warm the most and possibly experience greater Fe supply under future climate conditions, such as coastal regions. This may result in changes in phytoplankton community structures with implications for carbon sequestration efficiency under future climate conditions. [ABSTRACT FROM AUTHOR]

The benefits of dietary fiber on intestinal health have been well established. However, there is no consensus on the dietary fiber effects on mineral absorption. The objective of this systematic review is to discuss the evidence on the dietary fiber effects on iron absorption and iron status-related biomarkers. A comprehensive search of 3 databases: PubMed, Scopus and Web of Science was carried out. We followed the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines, and a total of 32 studies were included with 9 of them clinical studies and 23 in vivo. The studies included assessment of dietary fiber in the form of fructo-oligosaccharides, galacto-oligosaccharides, inulin, pectin, guar gum, oligofructose, xylo-oligosaccharides, and mannan-oligosaccharide. Hemoglobin (n = 21) and fractional iron absorption (n = 6) were the most frequently reported outcomes. The results showed no significant correlations between consumption of dietary fiber to iron absorption/status-related biomarkers. However, the current evidence may not be substantial to invalidate the recommendation of dietary fiber as an agent to improve dietary iron bioavailability, and absorption. In conclusion, there is a need to conduct further clinical trials with long dietary fiber intervention focusing on population at high risk for iron deficiency. [ABSTRACT FROM AUTHOR]

Bean flour is a highly nutritive, plant-based ingredient with the potential for great utility in many food products. Heat treated flours produced from commercial varieties of white kidney, yellow and black beans, were processed into pastas using high/low extrusion and drying temperatures. Bean pastas made with high extrusion/high drying temperature (H/H) had more favorable sensory attributes and better texture than those made with high extrusion/low drying temperature (H/L). Whereas bean pastas made with low extrusion/low drying temperature (L/L) were unacceptable. H/H pastas favored longer cooking time (8.6 – 13.8 min) versus those extruded at lower temperature (5.0 – 5.7 min). High extrusion temperature (100 °C) with drying temperature high (90 °C) improved iron bioavailability from yellow and white kidney bean pastas, 12.7 and 15 ng ferritin/mg protein, respectively as compared to black bean pasta (0.9 ng ferritin/mg protein). Cultivar, extrusion and drying temperatures are critical for producing bean pastas with high iron bioavailability.

Iron deficiency anemia (IDA) is a major global health problem. Tegillarca granosa has been considered as an excellent source of iron given its high content of iron-binding protein, ferritin. The aim of the present study was to determine the physicochemical properties, protein structures, and iron uptake of ferritin extracted from T. granosa, and to evaluate the potential impacts of chitosan glycosylation on these characteristics. Based on Box-Behnken design and response surface methodology, the optimal conditions for glycosylation included a ferritin/chitosan mass ratio of 4:1, a pH of 5.5, a reaction time of 10 min, and a reaction temperature of 50 °C. Glycosylation caused decreased surface hydrophobicity and elevated water-holding capacity of ferritin due to the introduction of hydrophilic groups. Additionally, glycosylation improved antioxidant capacity of ferritin by 20.69%–189.66%, likely owing to the protons donated by saccharide moiety to terminate free radical chain reaction. The in vitro digestibility of ferritin was elevated by 22.56%–104.85% after glycosylation, which could be associated with less β-sheet content in secondary structure that made the glycosylated protein less resistant to enzymatic digestion. The results of the iron bioavailability in Caco-2 cells revealed that ferritin (78.85–231.77ng mg−1) exhibited better iron bioavailability than FeSO4 (51.48–114.37 ng mg−1) and the values were further elevated by glycosylation with chitosan (296.23–358.20 ng mg−1), which may be related to the physicochemical properties of ferritin via glycosylation modification. These results provide a basis for the development of T. granosa derived ferritin and its glycosylated products, and can promote the utilization of aquatic resources. [ABSTRACT FROM AUTHOR]

Antarctic krill protein–iron complex and peptide–iron complex were acquired to investigate their iron bioavailability, expression of iron-regulated genes, and in vivo antioxidant capacity. Results indicated that the Antarctic krill peptide–iron complex significantly increased the hemoglobin (Hb), serum iron (SI), and iron contents in the liver and spleen in iron-deficiency anemia (IDA) mice (p < 0.05) compared with those of the Antarctic krill protein–iron complex. Despite the gene expressions of the divalent metal transporter 1(DMT1), the transferrin (Tf), and the transferrin receptor (TfR) being better regulated by both Antarctic krill peptide–iron complex and protein–iron complex, the relative iron bioavailability of the Antarctic krill peptide–iron complex group (152.53 ± 21.05%) was significantly higher than that of the protein–iron complex group (112.75 ± 9.60%) (p < 0.05). Moreover, Antarctic krill peptide–iron complex could enhance the antioxidant enzyme activities of superoxidase dismutase (SOD) and glutathione peroxidase (GSH-Px), reduce the malondialdehyde (MDA) level in IDA mice compared with the protein–iron complex, and reduce the cell damage caused by IDA. Therefore, these results indicated that Antarctic krill peptide–iron complex could be used as a highly efficient and multifunctional iron supplement. [ABSTRACT FROM AUTHOR]

Background and objective: Iron deficiency is a global health concern. Fortification of foods with iron is a common strategy to solve the nutritional issue. However, traditional iron fortification methods lead to some challenges with regard to stability and bioavailability of the element. Therefore, finding alternative approaches have been developed. One approach is use of iron-chelating peptides derived from milk proteins. They have attracted a lot of interests in the scientific community due to their potential to enhance iron absorption and bioavailability. This article provides a review on iron-chelating peptides and hydrolysates derived from halal milks, shedding light on their underlying principles in iron complexation and the key binding sites involved. Results and conclusion: The significance of iron-chelating peptides lies in their ability to address the critical issue of dietary iron deficiency. Halal milks' protein-iron complex offer several advantages such as superior bioavailability, minimal impact on taste, and excellent solubility. These characteristics introduce them as promising strategy in iron fortification of halal foods. These complexes are formed through specific chemical interactions between iron and the breakdown products of milk proteins, including hydrolysates or peptides, derived from both whey protein and casein. Several factors affect the efficacy of iron binding including pH, ionic strength, concentration of peptides to reach ideal ratio, temperature and time, appropriate enzyme (which impacts on the peptide characteristic), and potential interaction with other molecules. This multifaceted approach to enhance the iron fortification effectiveness underscores the importance of a deeper understanding of the intricate interplay between these factors in development of iron-fortified foods. [ABSTRACT FROM AUTHOR]

The high prevalence of iron deficiency in humans, alongside the lack of sustainable iron sources call for alternatives. Although understudied, edible insects are high in potentially bioavailable iron. Insect ferritin is thought to make insect-based iron bioavailable (entoferritin). This review examined the use of entoferritin as an iron supplement based on its properties and comparison to mammalian and plant ferritins. Entoferritin is a large, soluble, iron-affine transporting protein complex. These features enable mild entoferritin purification. These purifying methods may not affect other products due to the common structure of edible insect processing chains. The protein complex can accumulate an abundance of bioavailable iron and be absorbed through a human endocytosis mechanism. However, insect ferritin delivery systems into the human iron pool, bioavailability and safety have various possible limits and require further exploration. This paper suggests that entoferritin could help the valorization of edible insects and fight iron deficiency.

Dalam kehamilan anemia merupakan faktor penting yang terkait dengan peningkatan risiko kematian ibu anak. Asupan zat besi dan bioavailabilitas zat besi penting untuk pencegahan anemia defisiensi besi. Penelitian ini bertujuan untuk menganalisis perbedaan asupan makanan dan bioavailabilitas zat besi ibu hamil anemia dan non-anemia di Puskesmas Makasar. Studi cross sectional dilakukan pada 185 wanita hamil dari Mei -September 2019 di Puskesmas Kecamatan Makasar, Jakarta. Asupan makan diukur dengan menggunakan 24 hours food recall dan Semi Quantitative Food Frequency. Lingkar lengan atas diukur dengan metline. Kadar hemoglobin diukur dengan metode cyanmethameglobin. Data dianalisis dengan uji beda dengan nilai p0,05). Secara umum total energi dan asupan protein ibu hamil kurang dari 70% EAR. Asupan makanan pada kelompok anemia lebih tinggi daripada kelompok non-anemia. Tidak ada perbedaan dalam zat besi heme dan non-heme pada anemia dan non-anemia, tetapi kelompok anemia cenderung memiliki asupan zat besi non-heme yang lebih tinggi. Dalam penelitian ini tidak adak perbedaan asupan zat besi pada ibu hamil anemia dan non-anemia.

In this work, an egg yolk protein hydrolysate (EYPH) with a high iron-chelating ability (87.32%) was prepared. The fractionation using 60% (v/v) ethanol concentration (E3 fraction) led to the efficiently accumulating the iron-chelating peptides in EYPH. The characterization results showed that iron mainly chelated with carboxyl, amino and phosphate groups of peptides. From E3 fraction, six iron-chelating peptides with MW ranging from 1372.36 to 2937.04 Da were identified and a hypothesized molecular model of DDSSSpSpSpSpSpSVLSK-Fe was simulated. In vitro stability determination showed that E3-Fe chelate owned a good heat, alkalinity and digestion tolerance, but a relatively bad acid tolerance. Finally, iron transport analysis showed that iron in the E3-Fe would be absorbed in caco-2 cell membrane more effectively than that of iron salts, indicating that it was possible to apply the E3-Fe complex as iron supplements.

Iron deficiency is a common public health problem in the UK. This review examines the role of meat in iron nutrition, focusing on the most vulnerable groups of the UK population. Meat contains haem iron which is absorbed by a different pathway to non-haem iron found in cereals and vegetables. A summary of absorption data from studies using isotopically-labelled haem iron shows that, although there is a wide degree of variation, haem iron bioavailability is consistently higher than non-haem iron. The importance of meat alternatives, such a plant protein, insects, and biofortified crops as a supply of bioavailable iron, and the use of food iron fortification is reviewed. Finally, the consequences of excluding meat from the diet in relation to dietary iron requirements is discussed.

Heart failure, renal dysfunction, anemia, and iron deficiency affect each other and form a vicious cycle, a condition referred to as cardiorenal anemia iron deficiency syndrome. The presence of diabetes further accelerates this vicious cycle. Surprisingly, simply inhibiting sodium-glucose co-transporter 2 (SGLT2), which is expressed almost exclusively in the proximal tubular epithelial cells of the kidney, not only increases glucose excretion into the urine and effectively controls blood glucose levels in diabetes but can also correct the vicious cycle of cardiorenal anemia iron deficiency syndrome. This review describes how SGLT2 is involved in energy metabolism regulation, hemodynamics (i.e., circulating blood volume and sympathetic nervous system activity), erythropoiesis, iron bioavailability, and inflammatory set points in diabetes, heart failure, and renal dysfunction. [ABSTRACT FROM AUTHOR]

Maize is a staple food for many communities with high levels of iron deficiency anemia. Enhancing the iron concentrations and iron bioavailability of maize with traditional breeding practices, especially after cooking and processing, could help alleviate iron deficiency in many of these regions. Previous studies on a small number of maize genotypes and maize flour products indicated that degermination (germ fraction removed with processing) could improve the iron bioavailability of maize. This study expanded upon this research by evaluating the iron bioavailability, mineral concentrations, and phytate concentrations of 52 diverse maize genotypes before (whole kernels) and after degermination. Whole and degerminated maize samples were cooked, dried, and milled to produce corn flour. Iron bioavailability was evaluated with an in vitro digestion Caco2 cell bioassay. In 30 of the maize genotypes, bioavailable iron increased when degerminated, thus indicating a higher fractional iron uptake because the iron concentrations decreased by more than 70% after the germ fraction was removed. The remaining 22 genotypes showed no change or a decrease in iron bioavailability after degermination. These results confirm previous research showing that the germ fraction is a strong inhibitory component for many maize varieties. Phytate concentrations in maize flours were greatly reduced with degermination. However, the relationship between phytate concentrations and the iron bioavailability of processed maize flour is complex, acting as either inhibitor or promoter of iron uptake depending on the color of the maize kernels and processing method used to produce flour. Other factors in the maize endosperm fractions are likely involved in the effects of degermination on iron bioavailability, such as vitreous or floury endosperm compositions and the polyphenol content of the bran. This study demonstrates that iron nutrition from maize can be enhanced by selecting genotypes where the inhibitory effect of the bran color and endosperm fraction are relatively low, especially after processing via degermination. [ABSTRACT FROM AUTHOR]

The eutrophication of aquatic systems is a problem related to the contribution of excess nutrients—phosphorus (P) and nitrogen (N)—to water bodies, which produces an increase in cyanobacterial blooms. Under eutrophic conditions, P and N concentrations are sufficient for cyanobacteria growth, and some micronutrients are considered to become limiting for population growth. This work aimed to assess the effect of iron on cyanobacteria growth and the content of MCs in natural populations of Microcystis spp. Microcosm setting experiments were carried out with natural samples collected during two bloom events of Microcystis spp., kept under controlled light, temperature and pH conditions. The first bloom sample was exposed to different iron concentrations (400, 700 and 1100 µg Fe·L−1) to determine the optimum concentration for growth. The second was exposed to different iron addition modes (one: T1P, and two pulses: T2P) to imitate the iron increase produced by the downward migration of Microcystis spp. colonies. Our results show that iron is a growth-promoting factor and that its optimal range of concentrations for the growth of Microcystis spp. under the experimental setting conditions is between 700 and 1100 µg Fe·L−1. On the other hand, growth rates were not significantly different between T1P and T2P; thus, different addition modes did not have an effect on growth. Regarding microcystin content, the MC quota in natural populations of Microcystis spp. did not show a clear relationship with the iron supply. This work contributes to the understanding of the underlying factors affecting cyanobacteria bloom formation and the production of MCs, which in turn would impact the development of management strategies to control cyanobacteria blooms. [ABSTRACT FROM AUTHOR]

Iron deficiency anemia (IDA) is a global health concern affecting one‐third of the world's population, particularly those dominated by plant‐based food. Fortifying staple foods with iron has been an effective strategy for preventing IDA. Pneumatophorus japonicus is an essential economic fish in China. Pneumatophorus japonicus dark meat is usually underutilized as a byproduct, though it contains bounteous nutrients, including heme iron (10.50 mg/100 g). This study aimed to investigate the iron bioavailability of P. japonicus dark meat and to evaluate its potential as an iron fortifier for whole‐wheat flour, a typical staple food, using an in vitro digestion/Caco‐2 cell culture system. Our results suggested the excellent iron bioavailability of P. japonicus dark meat in comparison with beef (a heme dietary iron reference), whole‐wheat flour (a non‐heme dietary iron reference), and FeSO4 (a conventional iron supplement). The addition of P. japonicus dark meat notably enhanced iron solubility, bioavailability, and protein digestibility of whole‐wheat flour. The flour‐dark meat mixture yielded 1.96 times the iron bioavailability compared to beef per gram. The iron bioavailability was further improved by adding vitamin C, a commonly used dietary factor, at the Vc/iron mass ratio of 2:100‐5:100. Our findings reveal the promise of P. japonicus dark meat as a significant source of bioavailable iron, providing a basis for developing fish byproducts as alternatives for iron supplementation. Practical Application: This study investigated the iron bioavailability of Pneumatophorus japonicus meat using in vitro digestion/Caco‐2 cell culture system. These results could be used to improve the utilization of Pneumatophorus japonicus byproduct (dark meat) and develop the potential of the byproduct as an iron fortifier for whole‐wheat flour. [ABSTRACT FROM AUTHOR]

• The bioavailability of iron may be correlated with the growth of A. pacificum (Group IV). • Siderophores produced by bacteria may facilitate the provision of bioavailable iron for A. pacificum. • Hydroxamate siderophores may serve as specific agents for the efficient uptake of iron. • Bacteria may influence STX toxicity and the synthesis of A. pacificum in conditions of iron scarcity. Specific bacterial species induce algal blooms by producing growth-promoting substances, such as siderophores, under iron-limited conditions. However, the molecular mechanisms underlying these effects remain poorly understood. This study investigates the interactions between the harmful dinoflagellate Alexandrium pacificum (Group IV) and siderophore-producing bacteria, with a focus on iron acquisition facilitated by bacterial siderophores. During algal bloom seasons in the South Sea of Korea, Photobacterium sp. TY1-4 was isolated, which enhances A. pacificum cell density under iron-deficient conditions, TY1-4 can use the sterile exudates from A. pacificum as the sole source of carbon , suggesting a mutualistic relationship. Transcriptomic and genomic analyses revealed siderophore-mediated redox-based signaling and non-reductive pathways enhancing iron bioavailability. Photobacterium sp. TY1-4 initiates siderophore production through quorum sensing, whereas A. pacificum utilizes specific receptors and transporters for hydroxamate-type siderophores (ApFHUA and ApFHUC) to uptake iron. Three redox key iron-uptake genes were also identified in A. pacificum : membrane-bound ferroxidase ApFET3 , high-affinity iron permease ApFTR1 , and ferric-chelate reductases/oxidoreductases ApFRE1 , with transcription levels inversely related to bioavailable iron. Increased iron bioavailability mediated by siderophores alleviates iron stress in A. pacificum , supporting its growth in iron-scarce environments. Additionally, A. pacificum co-cultured with Photobacterium sp. TY1-4 synthesized high-toxicity STXs, including GTX4, GTX2, and STX. These findings highlight the critical role of bacterial siderophores in iron binding and their potential impact on harmful algal bloom dynamics. [Display omitted] [ABSTRACT FROM AUTHOR]

Maize is a staple food for many communities with high levels of iron deficiency anemia. Enhancing the iron concentrations and iron bioavailability of maize with traditional breeding practices, especially after cooking and processing, could help alleviate iron deficiency in many of these regions. Previous studies on a small number of maize genotypes and maize flour products indicated that degermination (germ fraction removed with processing) could improve the iron bioavailability of maize. This study expanded upon this research by evaluating the iron bioavailability, mineral concentrations, and phytate concentrations of 52 diverse maize genotypes before (whole kernels) and after degermination. Whole and degerminated maize samples were cooked, dried, and milled to produce corn flour. Iron bioavailability was evaluated with an in vitro digestion Caco2 cell bioassay. In 30 of the maize genotypes, bioavailable iron increased when degerminated, thus indicating a higher fractional iron uptake because the iron concentrations decreased by more than 70% after the germ fraction was removed. The remaining 22 genotypes showed no change or a decrease in iron bioavailability after degermination. These results confirm previous research showing that the germ fraction is a strong inhibitory component for many maize varieties. Phytate concentrations in maize flours were greatly reduced with degermination. However, the relationship between phytate concentrations and the iron bioavailability of processed maize flour is complex, acting as either inhibitor or promoter of iron uptake depending on the color of the maize kernels and processing method used to produce flour. Other factors in the maize endosperm fractions are likely involved in the effects of degermination on iron bioavailability, such as vitreous or floury endosperm compositions and the polyphenol content of the bran. This study demonstrates that iron nutrition from maize can be enhanced by selecting genotypes where the inhibitory effect of the bran color and endosperm fraction are relatively low, especially after processing via degermination.

Iron deficiency anemia (IDA) is a common micronutrient deficiency. Tegillarca granosa (T. granosa) is a good source of iron due to its high content of hemoglobin. The present study aimed to determine the effects of glycosylation on structure, physicochemical characteristics and iron bioavailability of hemoglobin. Using Box-Behnken design and response surface methodology, the optimal conditions for hemoglobin-chitosan glycosylation were obtained: 61.8 °C, pH 6.3, hemoglobin/chitosan mass ratio of 4.3 and reaction time of 15 min. The formation of hemoglobin-chitosan conjugates was verified by SDS-PAGE and fluorescence spectroscopy. The surface hydrophobicity of hemoglobin was reduced by 20.90–65.05 % after glycosylation, along with the observations of elevated water-holding capacity, likely owing to the introduction of hydrophilic groups. Antioxidant capacity of glycosylated products (0.41–0.66 μM Trolox/mg protein) was markedly greater than that of original protein (0.06 μM Trolox/mg protein) due to the formation of brown polymers with antioxidant activity. In addition, glycosylation improved in vitro digestibility of hemoglobin by 41.15–69.09 %, which could be attributed to less β-sheet in secondary structures. Moreover, hemoglobin (324.38 ng/mg) exhibited better iron absorption than FeSO 4 (121.63 ng/mg), with the value being further enhanced by glycosylation (442.73 ng/mg), which may be due to the improved protein digestibility and iron-chelating capacity. [ABSTRACT FROM AUTHOR]

Introduction and objective Iron is an essential mineral, the reserves of which in people on a plant­based diet are lower than in regular meat­consumers. The aim of the study was to summarize knowledge on factors that inhibit and improve iron absorption and on ways how to properly compose and prepare meals in order to maximize the bioavailibility of this micronutrient. Review methods The article is based on a literature review covering the following issues: iron status of vegans and vegetarians, iron bioavailability, factors reducing and improving iron absorption. The study is mainly based on the results of research involving human subjects. The publications used originate from electronic databases – PubMed and Google Scholar. Brief description of the state of knowledge In order to increase the absorption of iron from plant foods, a source of vitamin C should be added to meals, preferably raw vegetables or fruits. Various types of seeds (cereals, nuts, legumes) should be soaked before consumption; one should also consume sprouted seeds and fermented products. It is recommended not to drink with meals, especially tea and coffee, and to eat foods rich in iron and calcium in one meal. It may be helpful to introduce iron­fortified products into the diet and appropriate probiotic therapy. Summary People on a properly balanced plant diet, covering the recommended daily intake for iron, are not more likely to develop iron deficiency anaemia than people on a mixed diet. However, in order to meet the need for iron, increased in vegans (especially in women), it is necessary not only to choose products rich in this micronutrient, but also to properly compose and prepare meals.

Copyright of Indonesian Journal of Human Nutrition is the property of Brawijaya University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Plant-based foods such as hummus are alternative to animal protein, and when properly prepared, they help to alleviate nutritional iron deficiency that leads to anemia, a global health problem. Objective: The objective was to assess iron intake among Lebanese women and related participant’s characteristics, discern iron-rich dietary patterns, evaluate their association with nutrients intake and participant’s sociodemographic characteristics, and identify the women preparing hummus traditionally and properly for an enhanced iron bioavailability. Design: A cross-sectional study of 400 Lebanese women (18–74 years old) was conducted in Lebanon. Data from a questionnaire, including sociodemographic and health characteristics, dietary intake, and hummus preparation and consumption, were collected. Dietary data were obtained by a food frequency questionnaire and a 24-h recall. Dietary patterns were identified by principal component analysis. Linear regression and binomial logistic regression models were used to explore the association between the intake of dietary iron, its patterns, and the participants’ characteristics. Results: About 60% of the women had iron intake deficiency, especially with lower income (odds ratio [OR] = 1.88, 95% confidence interval [CI]: 1.107, 3.194). Four iron-rich dietary patterns were identified: legumes; organ/lunch meat and chicken; canned fish; and beef and hummus. The factor scores of the latter were positively correlated with protein, vitamin C, iron, folate, vitamin B12, and vitamin A with r = 0.195 and P < 0.01 for all. No significant difference was shown among the women’s sociodemographic characteristics for the consumption of the hummus-related pattern. Only 9.2 and 22.7% of the women considered proper preparation of chickpea and hummus, respectively, which significantly (P < 0.05) correlated with older women (66.7%). Discussion & Conclusion: The majority of the Lebanese women still have iron intake deficiency and the minority reported proper preparation of hummus. Intervention programs spreading awareness among Lebanese women are needed for encouraging adequate iron intake and considering proper steps to improve iron bioavailability from plant-based food.

For cereal-based foods rich in dietary fibers, iron bioavailability is known to be poor. For native cereal β-glucan extracts, literature has demonstrated that the main factor impacting the bioavailability is phytic acid, which is often found in association with dietary fibers. During food processing, β-glucan can undergo modifications which could potentially affect the equilibrium between phytic acid, fiber, and iron. In this study, an in vitro digestion was used to elucidate the iron dialysability, and hence estimate iron availability, in the presence of native, chelating resin (Chelex)-treated, oxidised, or partially hydrolysed oat and barley β-glucan extracts (at 1% actual β-glucan concentration), with or without phytase treatment. It was confirmed that pure, phytic acid-free β-glucan polysaccharide does not impede iron availability in cereal foods, while phytic acid, and to a smaller extent, also proteins, associated to β-glucan can do so. Neither Chelex-treatment nor partial hydrolysis, 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO) or NaIO4 oxidation significantly influenced the phytic acid content of the β-glucan extracts (ranging 2.0–3.9%; p > 0.05). Consequently, as long as intrinsic phytic acid was still present, the β-glucan extracts blocked the iron availability regardless of source (oat, barley) or Chelex-treatment, partial hydrolysis or NaIO4-oxidation down to 0–8% (relative to the reference without β-glucan extract). Remarkably, TEMPO-oxidation released around 50% of the sequestered iron despite unchanged phytic acid levels in the modified extract. We propose an iron-mobilising effect of the TEMPO product β-polyglucuronan from insoluble Fe(II)/phytate/protein aggregates to soluble Fe(II)/bile salt units that can cross the dialysis membrane. In addition, Chelex-treatment was identified as prerequisite for phytase to dramatically diminish iron retention of the extract for virtually full availability, with implications for optimal iron bioavailability in cereal foods.

Food-to-food fortification (FtFF) with moringa leaf (iron source) and/or baobab fruit (citric acid and ascorbic acid source) (each 13–15 g/100 g porridge dry basis (db)) was studied to improve iron and zinc nutritive quality in African-type wholegrain maize-based porridges using in vitro dialysability assay. Moringa FtFF decreased percentage and total bioaccessible iron and zinc, by up to 84% and 45%, respectively. Moringa was very high in calcium, approximately 3% db and calcium–iron–phytate complexes inhibit iron bioavailability. Baobab FtFF increased percentage and total bioaccessible iron and zinc, especially in porridges containing carrot + mango (β-carotene source) and conventionally fortified with FeSO4, by up to 111% and 60%, respectively. The effects were similar to those when ascorbic and citric acids were added as mineral absorption enhancers. While moringa FtFF could be inhibitory to iron and zinc bioavailability in cereal-based porridges, baobab fruit FtFF could improve their bioavailability, especially in combination with conventional iron fortification. [ABSTRACT FROM AUTHOR]

Iron deficiency is considered as a common problem facing the general world population. In the current research, experiments were conducted to evaluate the effects of aqueous extracts of Acacia senegal (Gum Arabic, GA), Spinacia oleracea (spinach), Zea mays (corn), and Capsicum annuum (red chili pepper) on iron and ferritin levels in rats. Vitamin C and fructose levels were first estimated in these plants by using High-Performance Liquid Chromatography (HPLC). The results showed that the GA extract contained the highest level of fructose (853 mg.L-1 ), followed by red chili pepper (635 mg.L-1 ), corn (521 mg.L-1 ), and spinach (271 mg.L-1 ) extracts. Also, the results of vitamin C estimation showed levels of 3.376, 0.645, 0.579, and 0.347 mg/ml in the extracts of spinach, red chili pepper, corn, and GA, respectively. Next, thirty male albino rats (age 8-12 weeks, weight 120-200 g) were divided randomly into six groups, each kept in a separate polypropylene rat cage. Treatments of rats with various plant extracts were conducted following a CRD complete random design, with five replicates for each treatment. The results of lipid profile test revealed that GA treatment caused the highest reduction in the serum levels of TC, TG, LDL, VLDL, and HDL in the treated rats (76.25, 55.25,23, 15.25, and 38 mg/dl, respectively), as compared to the other plant extracts. Evidence from this study suggests that the higher serum level of fructose in the group of rats treated with all plant extracts enhances the process of ferritin formation, possibly via increasing the level of bioavailable iron [ABSTRACT FROM AUTHOR]

Pomegranate juice is popular due to its unique health benefits, sensory characteristics and also a good source of bioactive compounds. Comparative study on processing effect of Not from Concentrate (NFC) and Reconstituted from concentrate (RFC) pomegranate juice on the nutritional and sensory characteristics of 'Ganesh' variant was conducted. Results showed that not much differences observed in parameters like pH, acidity, essential elements, protein, total sugars and polyphenol content between NFC and RFC. As per the study NFC had a better antioxidant activity with intracellular ROS inhibition of 11% higher with significant (p < 0.05) than RFC in HepG2 cell lines. Total anthocyanin content was significantly different (p < 0.05) in NFC (428.05 mg/l) compared to 326.74 mg/l in RFC expressed as cyanidin-3-glucoside. Iron uptake was 40 units (µg/mg protein) higher in NFC than RFC (p < 0.05) in HepG2 cells. Sensory flavor profile showed NFC having significant differences with respect to characteristic pomegranate freshness, fruitiness, sweetness and astringency mouthfeel. RFC had higher sweetish and cooked flavor with additional vegetable like notes of beet and carrot. Based on the data better antioxidant activity, iron bioavailability, anthocyanin content and sensory attributes were captured in pomegranate NFC juices over RFC juices. [ABSTRACT FROM AUTHOR]

Copyright of General Medicine & Health Sciences / Medycyna Ogólna i Nauki o Zdrowiu is the property of Witold Chodzki Institute of Rural Medicine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Iron (Fe) is an essential nutrient for microalgal metabolism. The low solubility of Fe in oxic aquatic environments can be a growth-limiting factor for phytoplankton. Synthetic chelating agents, such as ethylenediaminetetraacetic acid (EDTA), are used widely to maintain Fe in solution for microalgal cultivation. The non-biodegradable nature of EDTA, combined with sub-optimal bioavailability of Fe-EDTA complexes to microalgae, indicates opportunity to improve microalgal cultivation practices that amplify production efficiency and environmental compatibility. In the present study, the effects of four organic chelating ligands known to form readily bioavailable organic complexes with Fe in natural aquatic environments were investigated in relation to growth and biochemical composition of two marine microalgae grown as live feeds in shellfish hatcheries (Chaetoceros calcitrans and Tisochrysis lutea). Three saccharides, alginic acid (ALG), glucuronic acid (GLU), and dextran (DEX), as well as the siderophore desferrioxamine B (DFB), were compared to EDTA. Organic ligands characterized by weaker binding capacity for cationic metals (i.e., ALG, GLU, DEX) significantly improved microalgal growth and yields in laboratory-scale static batch cultures or bubbled photobioreactors. Maximal microalgal growth enhancement relative to the control (e.g., EDTA) was recorded for GLU, followed by ALG, with 20–35% increase in specific growth rate in the early stages of culture development of C. calcitrans and T. lutea. Substitution of EDTA with GLU resulted in a 27% increase in cellular omega 3-polyunsaturetd fatty acid content of C. calcitrans and doubled final cell yields. Enhanced microalgal culture performance is likely associated with increased intracellular Fe uptake efficiency combined with heterotrophic growth stimulated by the organic ligands. Based upon these results, we propose that replacement of EDTA with one of these organic metal-chelating ligands is an effective and easily implementable strategy to enhance the environmental compatibility of microalgal cultivation practices while also maximizing algal growth and enhancing the nutritional quality of marine microalgal species commonly cultured for live-feed applications in aquaculture. [ABSTRACT FROM AUTHOR]

Seed coat darkening after a delayed harvest or prolonged storage reduces the commercial value of dry beans and is caused by the oxidation of procyanidin compounds (condensed tannins). Slow-darkening (SD) pinto beans have a recessive gene (Psd), which alters procyanidin production – postponing their darkening over time. Procyanidins are important for the processing and nutrient bioavailability of beans, therefore, this study compared the postharvest cooking times and iron bioavailability of SD pinto varieties to regular-darkening (RD) pinto varieties. The results show SD pinto beans cook 30% faster and provide 2–7 times more bioavailable iron than RD pinto beans. No relationship between iron bioavailability, iron and phytate concentrations were detected among the pinto beans. However, lower procyanidin concentrations were strongly associated with faster cooking times and improved iron bioavailability of SD pinto beans. These findings indicate that the SD trait benefits the cooking quality and iron bioavailability of stored beans.

We present a new approach for quantifying the bioavailability of dissolved iron (dFe) to oceanic phytoplankton. Bioavailability is defined using an uptake rate constant (kin‐app) computed by combining data on: (a) Fe content of individual in situ phytoplankton cells; (b) concurrently determined seawater dFe concentrations; and (c) growth rates estimated from the PISCES model. We examined 930 phytoplankton cells, collected between 2002 and 2016 from 45 surface stations during 11 research cruises. This approach is only valid for cells that have upregulated their high‐affinity Fe uptake system, so data were screened, yielding 560 single cell kin‐app values from 31 low‐Fe stations. We normalized kin‐app to cell surface area (S.A.) to account for cell‐size differences. The resulting bioavailability proxy (kin‐app/S.A.) varies among cells, but all values are within bioavailability limits predicted from defined Fe complexes. In situ dFe bioavailability is higher than model Fe‐siderophore complexes and often approaches that of highly available inorganic Fe′. Station averaged kin‐app/S.A. are also variable but show no systematic changes across location, temperature, dFe, and phytoplankton taxa. Given the relative consistency of kin‐app/S.A. among stations (ca. five‐fold variation), we computed a grand‐averaged dFe availability, which upon normalization to cell carbon (C) yields kin‐app/C of 42,200 ± 11,000 L mol C−1 d−1. We utilize kin‐app/C to calculate dFe uptake rates and residence times in low Fe oceanic regions. Finally, we demonstrate the applicability of kin‐app/C for constraining Fe uptake rates in earth system models, such as those predicting climate mediated changes in net primary production in the Fe‐limited Equatorial Pacific. Plain Language Summary: In many oceanic regions, iron exerts strong control on phytoplankton growth, ecosystem structure, and carbon cycling. Yet, iron bioavailability and uptake rates by phytoplankton in the ocean are poorly constrained. Recently, Shaked et al. (2020) established a new approach for quantifying the availability of dissolved Fe (dFe) in natural seawater based on its uptake kinetics by Fe‐limited cultured phytoplankton. Here, we extend this approach to in situ phytoplankton, establishing a standardized proxy for dFe bioavailability in low‐Fe oceanic regions. Bioavailability is estimated through single cell Fe uptake constants, calculated by combining measured Fe contents of individual phytoplankton cells collected from multiple regions with concurrently measured dFe concentrations, as well as modeled growth rates. We then utilize this proxy for: (a) comparing dFe bioavailability among organisms and regions; (b) calculating dFe uptake rates and residence times in low‐Fe oceanic regions; and (c) constraining Fe uptake parameters of earth system models to better predict ocean productivity in response to climate change. Key Points: A proxy for dissolved Fe bioavailability in low‐Fe regions is established from Fe quotas, dissolved Fe concentrations, and modeled growth ratesIn situ phytoplankton cells record high and relatively uniform dissolved Fe bioavailability across many low‐Fe oceanic regionsThe new proxy is applicable for calculating in situ Fe uptake rates and biological Fe residence times and for validating global model output [ABSTRACT FROM AUTHOR]

Gelatin-based traditional Chinese medicines have long been used to treat anemia. Here, rats on the gelatin-based AIN-93G diet showed higher hemoglobin regeneration efficiencies and liver iron concentrations than those fed the diets based on several other animal proteins from muscle sarcoplasm and fibrils, egg white, whey and casein. However, among these animal proteins, gelatin had the lowest digestibility under simulated gastric-proximal intestinal digestion, and its hydrolysate showed the lowest capacity to aid iron absorption in Caco-2 monolayers via templating ferric oxyhydroxide nanoparticles. In another rat hemoglobin regeneration assay, dietary supplementations with gelatin and its two major degradation products, glycine and prolyl-hydroxyproline, revealed that gelatin boosted iron absorption not through glycine, but rather via prolyl-hydroxyproline, which had inhibitory and stimulatory effects on the plasma levels of hepcidin and erythropoietin, respectively. Dietary gelatin thus seems to enhance non-heme iron absorption via regulating systemic iron homeostasis rather than via solubilizing luminal ferric iron.

Iron and zinc malnutrition are global public health concerns afflicting mostly infants, children, and women in low- and middle-income countries with widespread consumption of plant-based diets. Common bean is a widely consumed staple crop around the world and is an excellent source of protein, fiber, and minerals including iron and zinc. The development of nutrient-dense common bean varieties that deliver more bioavailable iron and zinc with a high level of trait stability requires a measurement of the contributions from genotype, environment, and genotype by environment interactions. In this research, we investigated the magnitude of genotype by environment interaction for seed zinc and iron concentration and seed iron bioavailability (FeBIO) using a set of nine test genotypes and three farmers’ local check varieties. The research germplasm was evaluated for two field seasons across nine on-farm locations in three agro-ecological zones in Uganda. Seed zinc concentration ranged from 18.0 to 42.0 μg g–1 and was largely controlled by genotype, location, and the interaction between location and season [28.0, 26.2, and 14.7% of phenotypic variability explained (PVE), respectively]. Within a genotype, zinc concentration ranged on average 12 μg g–1 across environments. Seed iron concentration varied from 40.7 to 96.7 μg g–1 and was largely controlled by genotype, location, and the interaction between genotype, location, and season (25.7, 17.4, and 13.7% of PVE, respectively). Within a genotype, iron concentration ranged on average 28 μg g–1 across environments. Seed FeBIO ranged from 8 to 116% of Merlin navy control and was largely controlled by genotype (68.3% of PVE). The red mottled genotypes (Rozi Koko and Chijar) accumulated the most seed zinc and iron concentration, while the yellow (Ervilha and Cebo Cela) and white (Blanco Fanesquero) genotypes had the highest seed FeBIO and performed better than the three farmers’ local check genotypes (NABE-4, NABE-15, and Masindi yellow). The genotypes with superior and stable trait performance, especially the Manteca seed class which combine high iron and zinc concentrations with high FeBIO, would serve as valuable parental materials for crop improvement breeding programs aimed at enhancing the nutritional value of the common bean.

Phytic acid is an inhibitor of iron bioavailability, but it has been suggested that individuals may adapt to phytic acid over time, and that the salivary protein, cystatin SN, may be involved. This study evaluated the relationship between human cystatin SN levels and iron bioavailability after a phytic acid rich meal. Three groups of ten women consumed meals with: (1) 500 mg phytate sprinkles, (2) 500 mg phytate capsules, or (3) no phytic acid. Iron bioavailability was measured by the mealtime percentage of maximum iron recovery; cystatin SN was measured pre-and post-meal by enzyme-linked immunosorbent assay. Pre-to-post meal cystatin SN was positively correlated with improved iron bioavailability in group 1. Pre-to-post meal cystatin SN was correlated with improved iron absorption in groups 1 and 2. Cystatin SN recovery after phytic acid rich meals may be a physiological factor predicting iron bioavailability. [ABSTRACT FROM AUTHOR]

Iron and zinc malnutrition are global public health concerns afflicting mostly infants, children, and women in low- and middle-income countries with widespread consumption of plant-based diets. Common bean is a widely consumed staple crop around the world and is an excellent source of protein, fiber, and minerals including iron and zinc. The development of nutrient-dense common bean varieties that deliver more bioavailable iron and zinc with a high level of trait stability requires a measurement of the contributions from genotype, environment, and genotype by environment interactions. In this research, we investigated the magnitude of genotype by environment interaction for seed zinc and iron concentration and seed iron bioavailability (FeBIO) using a set of nine test genotypes and three farmers' local check varieties. The research germplasm was evaluated for two field seasons across nine on-farm locations in three agro-ecological zones in Uganda. Seed zinc concentration ranged from 18.0 to 42.0 μg g–1 and was largely controlled by genotype, location, and the interaction between location and season [28.0, 26.2, and 14.7% of phenotypic variability explained (PVE), respectively]. Within a genotype, zinc concentration ranged on average 12 μg g–1 across environments. Seed iron concentration varied from 40.7 to 96.7 μg g–1 and was largely controlled by genotype, location, and the interaction between genotype, location, and season (25.7, 17.4, and 13.7% of PVE, respectively). Within a genotype, iron concentration ranged on average 28 μg g–1 across environments. Seed FeBIO ranged from 8 to 116% of Merlin navy control and was largely controlled by genotype (68.3% of PVE). The red mottled genotypes (Rozi Koko and Chijar) accumulated the most seed zinc and iron concentration, while the yellow (Ervilha and Cebo Cela) and white (Blanco Fanesquero) genotypes had the highest seed FeBIO and performed better than the three farmers' local check genotypes (NABE-4, NABE-15, and Masindi yellow). The genotypes with superior and stable trait performance, especially the Manteca seed class which combine high iron and zinc concentrations with high FeBIO, would serve as valuable parental materials for crop improvement breeding programs aimed at enhancing the nutritional value of the common bean. [ABSTRACT FROM AUTHOR]

BACKGROUND: Iron supplements are limited by their poor absorption and low efficacy. A circadian feeding schedule would affect the circadian rhythm and improve nutrient metabolism. In this study, 18 iron‐deficient piglets were randomly assigned to three groups: a control group receiving a constant diet with mid‐iron (MI), a 'HL' group receiving a high‐iron (HI) diet at 8:00 h and a low‐iron (LI) diet at 18:00, and an 'LH' group receiving a LI diet at 8:00 and a HI diet at 18:00. The effects of circadian iron administration on iron absorption, iron status, and biological rhythm in iron‐deficient piglets were investigated. RESULTS: Serum iron and hemoglobin improved significantly (P < 0.05) but did not significantly differ in the circadian iron‐feeding groups (P > 0.05). Iron concentration in the liver and spleen was significantly higher in the LH group than in the HL group (P < 0.05), and mRNA expression of divalent metal transport 1 (DMT1), cytochrome B (CYBRD1) and ferroportin (FPN) genes in the duodenum was significantly elevated in the LH group (P < 0.05). The clock‐related genes showed differential expression in the duodenum, with greater mRNA expression for period (Per2) and cryptochrome (Cry1 and Cry2) in the LH group (P < 0.05). CONCLUSION: Circadian iron administration affected iron absorption and iron storage in pigs. Iron supplementation in the evening might be a more effective pattern for iron utilization. The rhythmic system in the intestine, driven by the time, played an important role in this process. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Developing safe and efficient iron supplements is significant for the alleviation of iron-deficient anemia (IDA). Myoglobin (Mb) is a heme-protein rich in bioavailable iron. Pneumatophorus japonicus (P. japonicus), one important economic fish in China, contain a high Mb level in its dark meat normally discarded during processing. The present study aimed to determine the structure, physicochemical properties, and iron bioavailability of Mb extracted from P. japonicus. Meanwhile, the effects of glycosylation, a commonly applied chemical modification of proteins, on these parameters were evaluated. Using Box-Behnken design, the optimal conditions for Mb-chitosan glycosylation were obtained: 45.07 °C, pH 6.10 and Mb/chitosan mass ratio of 6.29. The structure and functional properties of the glycosylated Mb (Mb-gly) were investigated. Compared with the original Mb, Mb-gly obtained a more ordered secondary structure. The surface hydrophobicity of Mb-gly was found to be decreased together with the observations of elevated water solubility. Moreover, glycosylation enhanced the Mb antioxidant capacity, and improved its stability in enzymatic digestion system. Regarding to the iron bioavailability, the cellular uptake of Mb‑iron was significantly higher than FeSO 4 , and further elevated by glycosylation. These results provided a basis for the development of Mb-based iron supplements, promoting the utilization of fish-processing industries wastes. [ABSTRACT FROM AUTHOR]

Biofilms are broadly formed by diverse microorganisms under stressful environments that are basically surrounded by an EPS matrix, which enable bacterial cells to confer the resistance to the biocides, antibiotics and other invasions. Yet, biofilms cause harmful impacts in various fields, including clinical infections, food contaminations and environmental pollution. However, the mechanism of biofilm formation remains incompletely elucidated, and currently, we lack an efficient strategy to tackle these tough problems by eradicating biofilms. In the present study, we sought to decipher the mechanism of biofilm formation in Escherichia coli from metabolic perspective. By exposing bacterial cells to various concentrations of iron, we found that iron can regulate biofilm formation, and the phenotypic changes were obviously dependent on iron concentration. A functional metabolome assay was further implemented to investigate the regulatory mechanism of iron on biofilm formation; we verified that siderophores mostly account for the transportation of iron into bacterial cells. Then, the bioavailable iron was recruited by bacterial cells to direct the levels of five functional metabolites (l -tryptophan, 5′-MTA, spermidine, CMP and L-leucine), which were identified as new effectors that directly regulate biofilm formation. Taken together, this study is the first to identify five functional metabolites to efficiently regulate biofilm formation, which can be targeted to tackle the harmful impacts associated with biofilm formation in different niches. Image 1 • LC/TQ based targeted metabolomics method was optimized to determine 100+ key microbial metabolites. • Iron was characterized to regulate biofilm formation through the mediation of bacterial metabolism. • Five functional metabolites were identified to confer functional regulation on the biofilm formation in E. coli. [ABSTRACT FROM AUTHOR]

Wild fruits and vegetables (WFV) are believed to contain substantial quantities of micronutrients and are commonly consumed in rural areas of developing countries endowed with natural vegetation. Previous studies that provided evidence on the contribution of WFV to household micronutrient intake in a developing country setting did not consider the effect of antinutritional factors. Therefore, applying the in vitro bioavailability assessment technique and using the Acholi subregion of Uganda a case area, this study examined the contribution of commonly consumed WFV to the pooled annual household dietary requirement for iron. Laboratory analysis showed that the concentration of antinutrients varied with plant species but the pool was dominated by phytate (10.5–150 mg/100 g) and phenolic substances (38.6–41.7 mg GAE/g). In vitro iron bioavailability varied with plant species was quantitatively higher from vegetables than fruits by 27% although total concentration of the micronutrient was higher in fruits than vegetables by 142%. Nutritional computation, taking into account, household composition, and physiological status revealed that consumption of WFV resulted in a median contribution of 1.8% (a minimum of 0.02 and a maximum of 34.7%) to the pooled annual household dietary iron requirements on the basis of bioavailable iron fraction. These results demonstrate that WFV contributes meagerly to household iron needs but may serve other dietary and non‐nutrient health purposes. [ABSTRACT FROM AUTHOR]

Background: Plant-based foods such as hummus are alternative to animal protein, and when properly prepared, they help to alleviate nutritional iron deficiency that leads to anemia, a global health problem. Objective: The objective was to assess iron intake among Lebanese women and related participant's characteristics, discern iron-rich dietary patterns, evaluate their association with nutrients intake and participant's sociodemographic characteristics, and identify the women preparing hummus traditionally and properly for an enhanced iron bioavailability. Design: A cross-sectional study of 400 Lebanese women (18--74 years old) was conducted in Lebanon. Data from a questionnaire, including sociodemographic and health characteristics, dietary intake, and hummus preparation and consumption, were collected. Dietary data were obtained by a food frequency questionnaire and a 24-h recall. Dietary patterns were identified by principal component analysis. Linear regression and binomial logistic regression models were used to explore the association between the intake of dietary iron, its patterns, and the participants' characteristics. Results: About 60% of the women had iron intake deficiency, especially with lower income (odds ratio [OR] = 1.88, 95% confidence interval [CI]: 1.107, 3.194). Four iron-rich dietary patterns were identified: legumes; organ/lunch meat and chicken; canned fish; and beef and hummus. The factor scores of the latter were positively correlated with protein, vitamin C, iron, folate, vitamin B12, and vitamin A with r = 0.195 and P < 0.01 for all. No significant difference was shown among the women's sociodemographic characteristics for the consumption of the hummus-related pattern. Only 9.2 and 22.7% of the women considered proper preparation of chickpea and hummus, respectively, which significantly (P < 0.05) correlated with older women (66.7%). Discussion & Conclusion: The majority of the Lebanese women still have iron intake deficiency and the minority reported proper preparation of hummus. Intervention programs spreading awareness among Lebanese women are needed for encouraging adequate iron intake and considering proper steps to improve iron bioavailability from plant-based food. [ABSTRACT FROM AUTHOR]

In this study, the molecular mechanisms of iron transport and homeostasis regulated by the Antarctic krill-derived heptapeptide-iron (LVDDHFL-iron) complex were explored. LVDDHFL-iron significantly increased the hemoglobin, serum iron, total iron binding capacity levels, and iron contents in the liver and spleen to normal levels, regulated the gene expressions of iron homeostasis, and enhanced in vivo antioxidant capacity in iron-deficiency anemia mice ( P < 0.05). The results revealed that iron ions within LVDDHFL-iron can be transported via the heme transporter and divalent metal transporter-1, and the absorption of LVDDHFL-iron involved receptor-mediated endocytosis. We also found that the transport of LVDDHFL-iron across cells via phagocytosis was facilitated by the up-regulation of the high mobility group protein, heat shock protein β, and V-type proton ATPase subunit, accompanied by the regulatory mechanism of autophagy. These findings provided deeper understandings of the mechanism of LVDDHFL-iron facilitating iron absorption.

Processing techniques can disrupt the cotyledon cell walls of raw beans, allowing digestive enzymes greater access to intercellular stores of micronutrients such as iron during digestion. This study evaluated the iron bioavailability of seven bean varieties with different seed coat colors (white, yellow, cranberry, red, black) either boiled or processed into spaghetti pastas formulated from heat treated bean flour as the major ingredient (90% bean flour). Iron bioavailability was significantly (p ≤ 0.05) higher in spaghetti made from white or yellow bean varieties Snowdon, Alpena, Samurai and Canario when compared to boiled beans. Although cotyledon cells were broken and the phytate to iron molar ratios were significantly lower, the iron bioavailability of the cranberry (Etna), red kidney (Red Hawk) and black (Zenith) bean varieties did not improve after processing into spaghetti. Iron bioavailability of bean-based pastas was associated with procyanidin and cinnamtannin compounds that have a negative impact on the absorption of iron.

Biostimulants could play an important role in agriculture particularly for increasing N fertilizer use efficiency that is essential for maintaining both yield and grain quality in bread wheat, which is a major global crop. In the present study, we examined the effects of mixing urea–ammonium–nitrate fertilizer (UAN) or urea with five new biostimulants containing Glutacetine® or its derivative formulations (VNT1, 2, 3, and 4) on the physiological responses, agronomic traits, and grain quality of winter wheat. A first experiment under greenhouse conditions showed that VNT1, VNT3, and VNT4 significantly increased the seed yield and grain numbers per ear. VNT4 also enhanced total plant nitrogen (N) and total grain N, which induced a higher N Harvest Index (NHI). The higher post-heading N uptake (for VNT1 and VNT4) and the acceleration of senescence speed with all formulations enabled better nutrient remobilization efficiency, especially in terms of N mobilization from roots and straw toward the grain with VNT4. The grain ionome was changed by the formulations with the bioavailability of iron improved with the addition of VNT4, and the phytate concentrations in flour were reduced by VNT1 and VNT4. A second experiment in three contrasting field trials confirmed that VNT4 increased seed yield and N use efficiency. Our investigation reveals the important role of these new formulations in achieving significant increases in seed yield and grain quality. [ABSTRACT FROM AUTHOR]