Reductive immobilization of uranium by the stimulation of dissimilatory metal-reducing bacteria (DMRB) has been investigated as a remediation strategy for subsurface U(VI) contamination. In those environments, DMRB may utilize a variety of electron acceptors, such as ferric iron which can lead to the formation of reactive biogenic Fe(II) phases. These biogenic phases could potentially mediate a...

There is persuasive epidemiological evidence that regular intake of dietary bioactive polyphenolic compounds promotes human health. Because dietary polyphenolic compounds have a wide range of effects in vivo and vitro, including chelation of metals such as iron, it is prudent to test whether the regular consumption of bioactive polyphenolic components impair the utilization of dietary iron. We ...

Increased oxygen reduction reaction (ORR) kinetics, improved CO tolerance, and more efficient water and heat management represent significant advantages that high-temperature polymer electrolyte fuel cells (HT-PEFCs) operating with a phosphoric acid-doped polybenzimidazole (PBI) membrane offer over traditional Nafion-based, low-temperature PEFCs. However, before such HT-PEFCs become viable, the...

Iron (Fe) minerals and ferrous iron (Fe(II)) play an important role in the several natural elemental cycles, including the carbon cycle, nutrient cycles, and the cycling of metals. In this work we have characterized the reactivity structural Fe(II) in several Fe minerals and in natural soil with uranium. We have studied the reactivity of Fe(II) in solution with the Fe oxide goethite conditions ...

Postembryonic development of plants is dependent on both intrinsic genetic programs and environmental factors. The plasticity of root hair patterning in response to environmental signals was investigated in the Columbia-0 wild type and 19 Arabidopsis mutants carrying lesions in various parts of the root hair developmental pathway by withholding phosphate or iron (Fe) from the nutrient medium. I...

Each R2 subunit of mammalian ribonucleotide reductase contains a pair of high spin ferric ions and a tyrosyl free radical essential for activity. To study the mechanism of tyrosyl radical formation, substoichiometric amounts of Fe(II) were added to recombinant mouse R2 apoprotein under strictly anaerobic conditions and then the solution was exposed to air. Low temperature EPR spectroscopy showe...

Plants have developed a wide-range of adaptations to overcome nutrient limitation, including changes to the quantity and composition of carbon-containing compounds released by roots. Root-associated bacteria are largely influenced by these compounds which can be perceived as signals or substrates. Here, we evaluate the effect of root exudates collected from maize plants grown under nitrogen (N)...

BACKGROUND Fortification of milk formulas with iron is a strategy widely used, but the absorption of non-heme iron is low. The purpose of this study was to measure the bioavailability of two iron fortified milk formulas designed to cover toddlers´ nutritional needs. These milks were fortified with iron sulfate stabilized with maltodextrin and citric acid. METHODS 15 women (33-47 years old) pa...

BACKGROUND Erythorbic acid, a stereoisomer of ascorbic acid with similar physicochemical properties, is widely used as an antioxidant in processed foods. OBJECTIVES The aims of the present study were to evaluate the effect of erythorbic acid on iron absorption from ferrous sulfate at molar ratios of 2:1 and 4:1 (relative to iron) and to compare the effect of erythorbic acid directly with that...

Agricultural drainage water continues to impact watersheds and their receiving water bodies. One approach to mitigate this problem is to use surrounding natural wetlands. Our objectives were to determine the effect of iron (Fe)-rich groundwater on phosphorus (P) removal and nutrient absorption by the utilization of the iron plaque on the root surface of Glyceria spiculosa (Fr. Schmidt.) Rosh. T...