The hydroxylation of y-butyrobetaine (4-trimethylaminobutyrate) to carnitine (3-hydroxy-4-trimethylaminobutyrate) is catalyzed by a soluble enzyme from rat liver which has been partially purified. The enzyme which previously has been shown to require molecular oxygen and ferrous ion has a specific requirement for 2-ketoglutarate. Several reductams stimulate the formation of hydroxylated product...

−− The spectrophotometric method for the determination of cuprous ions in solution presented by Anwar et al. (2000), has since been analyzed and improved, especially with regard to interference from iron and ion species commonly found in acid mine drainage (AMD). The reduction of cupric ions in the presence of ferrous ions, not considered by Anwar et al., renders this method unfeasible for cupr...

The surface topography developed on copper-based and ferrous alloys after being sputtered in a glow discharge lamp and in an ion microprobe was studied by means of a scanning electron microscope and an ion microprobe mass analyser. The observed surface topography, though obtained under completely different conditions, was found to be similar to that predicted by the theory of Stewart and Thompson.

In the present in vitro study, the effects of pH and ionic strength on the release of iron from pectin and the ability of pectin to reduce ferric iron to ferrous iron were examined. The bioavailability of Fe bound to pectin was evaluated in rats. The amount of Fe released from pectin was at a maximum at pH 2·0 and decreased as the pH value increased. At pH 2·0, the amount of Fe released from pe...

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 Fe ion to Fe ions which diffuse through the gel matrix and blur the image of absorbed dose over a period of hours after ...

The objective of this work is to examine the influence of oxalic acid formed on the degradation of phenol by Fenton reagent. Oxalic acid formed at initial stage within 30 min significantly suppresses the reduction of ferric ion, thus terminating degradation reaction. The yield of oxalic acid is dependent on the amount of ferrous ion dosed since the minimal amount of oxalic acid is formed after ...

Artemisinin, a sesquiterpene with endoperoxide bond, possesses potent antimalarial activity against the ring and late stage of chloroqine-resistant Plasmodium falciparum malaria both in vitro and in vivo. The mode of antimalarial activity of artemisinin is iron-dependent. The aim of this study was to investigate the reactions of artemisinin with ferrous and ferric ions in aqueous buffer. Artemi...

In this study, the effects of some factors on bacterial growth and ferrous oxidation rates were investigated by Acidithiobacillus ferrooxidan in 250 ml shake flasks. One factor at a time (OFAT) design approach was used for preliminary evaluation of various factors affecting the process, such as pH, initial ferrous and elemental sulfur concentrations, shaker agitation rate, and liquid to flask v...

Beef heart aconitase, isolated under aerobic conditions, has been studied with Mössbauer and EPR spectroscopy. In the oxidized state, the enzyme exhibits an EPR signal at g = 2.01. The Mössbauer data show that this signal is associated with a 3Fe cluster. In dithionite-reduced aconitase, the 3Fe cluster, probably of the [3Fe-3S] type, is in a paramagnetic state of interger electronic spin (S = ...

AIM Catechins profile, caffeine content and antioxidant activity of different green tea and white tea samples commercialized on the Romanian market were investigated. MATERIAL AND METHODS Five green tea samples and five white tea samples commonly available on the Romanian market were processed by infusion and the lyophilisates of infusions were analyzed. Total phenolic content was determined ...