background: the compositions of ferrous sulphate, agarose and xylenol orange dye (fax) and ferrous sulphate, gelatin and xylenol orange dye (fgx) in solution of distilled water and sulphuric acid are two tissue-equivalent gel dosimeters. ionizing radiation causes oxidation of fe2+ ion to fe3+ ions which diffuse through the gel matrix and blur the image of absorbed dose over a period of hours af...

Flavonoids are a class of natural phenolic compounds that show antioxidant properties. Besides the known mechanisms of action of flavonoids (binding/inactivation of free radicals and other reactive oxygen species) that determine this effect, an important factor is their ability to bind transition metal ions. In this paper, we used a HPLC method with a prechromatographic reaction of a sample wit...

In an attempt to identify components of a ferric citrate uptake system in Pseudomonas aeruginosa, a mutant library of a siderophore-deficient strain (IA614) was constructed and screened for defects in citrate-promoted growth in an Fe-restricted medium. A mutant disrupted in gene PA3901, encoding a homologue of the outer-membrane ferric citrate receptor, FecA, of Escherichia coli (FecA(E.c.)), w...

An investigation was carried out aiming at assessing the potential of vis-NIR reflectance spectroscopy, through comparison with the conventional X-ray powder diffraction (XRPD) technique, for the characterization of synthetic gleys, obtained in laboratory starting from Fe0 and Fe2+ under different conditions of initial pH (5.5, 7.0 and 8.5). XRPD analysis showed that in any case goethite formed...

Anthocyanins from purple sweet potato (PSP) are peonidin and cyanidin glycosides acylated by p-hydroxycinnamic p-hydroxybenzoic acids. For six individual PSP pigments, the thermodynamic constants of proton transfer water addition were determined, which speciation diagrams for colored colorless forms UV–visible spectra could be constructed. The data confirm that acylation phenolic acids protects...

Nickel-iron layered double hydroxides (Ni-Fe LDHs) consist of stacked Fe3+-doped positively charged Ni-hydroxide layers containing charge-balancing anions and water molecules between the layers. Although Ni-Fe LDHs are highly active in oxygen evolution reaction (OER) under alkaline conditions, their poor operational stability remains an issue. Herein, based on density functional theory calculat...

The reaction of [Et3NHI[@-CO)Cu-RS)Fe2(C0)6] with bis(1-alkyny1)mercw-y compounds gave different products depending on the nature of the organomercurial. Bis(phenylethyny1)mercury and bis( 1-hexyny1)mercury gave p-q1:q2-acetylide complexes, @-q1:q2-CsCR1)@-RS)Fe2(CO)6, while bis(3-methoxy-1-propyny1)mercury and bis(3-(dimethylamino)-l-propynyl)mercury formed doubly bridging vinylcarbyne product...

The addition of calcium chloride to rat liver homogenates resulted in activation of phosphoenolpyruvate carboxykinase by as much as 50%. The enhanced activity was inhibited by quinolinic acid; it was not additive with activation by FeCl2, and stimulation was prevented by 1,10-phenanthroline. Activation by calcium was lost when the particulate fractions of liver were removed, but an activating s...

The ferric-uptake regulator (Fur) is an Fe2+-responsive transcription factor that coordinates iron homeostasis in many bacteria. Recently, we reported that expression of the Escherichia coli Fur regulon is also impacted by O2 tension. Here, we show that for most of the Fur regulon, Fur binding and transcriptional repression increase under anaerobic conditions, suggesting that Fur is controlled ...