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Se evaluó la bioadsorción de Co(II) y Mn(II) en soluciones acuosas por Rhodococcus opacus inactivado y tratado con NaOH, y se efectuó la caracterización fisicoquímica del bioadsorbente. La caracterización fisicoquímica de la bacteria se realizó mediante microscopía electrónica de barrido acoplada al análisis de dispersión de energía de rayos X (MEB-EDS), espectroscopía infrarroja por transformada de Fourier (FTIR) y potencial zeta (PZ). Asimismo, se determinaron las mejores condiciones de operación en el proceso, evaluando la concentración del biosorbente, concentración inicial del metal (Ci), pH y tiempo de contacto. Los experimentos se hicieron a escala de laboratorio y la bacteria fue previamente tratada con NaOH (0,1 M). La interacción entre R. opacus y los iones metálicos se confirmó por la variación del potencial isoeléctrico (PIE) y grupos funcionales. En las mejores condiciones de operación se alcanzaron remociones y adsorción de 87.8 % y 24.9 mg/g para Co(II), y 79.9 % y 6.1 mg/g para Mn(II). Estas condiciones fueron pH 7, biomasa 4 mg/l, Ci 50 mg/l y 180 minutos de tiempo de operación. Mientras que para el Mn(II): pH 5, biomasa 3 mg/l, Ci 5 mg/l y 10 minutos de tiempo de operación. El presente estudio demuestra que el R. opacus puede ser aplicado en el tratamiento de efluentes conteniendo bajas concentraciones de Co(II) y Mn(II).

The current study was conducted to measure the manganese content in nine different food groups. A cross-sectional study was designed; a total of 89 food items were randomly purchased from the main markets and hypermarkets in Alexandria Governorate, then digested by wet ashing procedure and finally analyzed using ICP-OES. The highest mean Mn value was obtained in the fat group (6.75 µg/g) compared to the other eight groups, followed by nuts (4.64 µg/g) and the protein-rich food group (4.52 µg/g), while meat and its products have the lowest mean of Mn (0.53 µg/g). Manganese content in food groups is strongly correlated with the food matrix, soil composition, and fortification process. Local butter, margarine, sunflower oil, corn oil, Scomberomorus commerson, poulty fish, pistachio, and walnuts had the highest content of manganese.

The first workshop evidence of the Caliphate polychrome tin-glaze production known as ‘verde y manganeso’ in al-Andalus has been found in the Cordoban workshops area. This study reports on the analysis of recovered firing debris and workshop items and the tin glaze production chaîne opèratoire using SEM-EDS and μ-XRD analysis. The findings reveal the use of a tin and lead calx mixed with plant ashes both in the Emirate and later Caliphate tin glaze productions and demonstrate a direct relationship between the Umayyad Córdoba- Madīnat al-Zahrā’ and the Abbasid regions. Moreover, ceramics from both domestic and palatial well-dated archaeological contexts from Córdoba and Madīnat al-Zahrā’ have been analysed to determine the differences among the domestic and palace wares and to shed light on the long running dispute among scholars regarding the location of the tin-glazed workshops. Our data demonstrate so far that the workshop area of Córdoba manufactured ‘verde y manganeso’ tin-glazed ceramics during the Caliphate period and that it could have been supplying both high-quality wares for the palaces and cheaper products for the domestic contexts.

The study was conducted to evaluate the effect of Zn and Mn source (inorganic vs. organic) in the diet for hens on laying performance, eggshell and bones quality. The experiment was carried out on 84 Hy Line Brown hens, from 25 to 70 weeks of age, allocated to seven experimental groups, each containing 12 hens individually caged on wire-mesh floor. All layers were fed the same basal diet with 52 mg Zn/kg and 30 mg Mn/kg. Experimental diets were supplemented with 30 mg Zn/kg and 50 mg Mn/kg and inorganic forms of Zn (ZnO) and Mn (MnO) were gradually replaced (in 0, 50 or 100%) with their organic sources (amino acid complexes). Egg production, egg weight, feed intake and feed efficiency were not affected by dietary treatments. Substitution of Zn and Mn oxides with amino acid complexes of microelements had no effect on physical and geometrical characteristics of tibia, ash content in tibia and in toes, eggshell percent, eggshell thickness and eggshell density, but improved (P less than 0.05) the eggshell breaking strength in the late phase of the laying cycle (at 62 and 70 weeks of age). Our results indicate that feeding Zn and Mn organic complexes could alleviate the negative effect of hen age on eggshell breaking strength.

▪ Abstract  New and exciting developments in boron research in the past few years greatly contributed to better understanding of the role of boron in plants. Purification and identification of the first boron-polyol transport molecules resolved much of the controversy about boron phloem mobility. Isolation and characterization of the boron-polysaccharide complex from cell walls provided the first direct evidence for boron crosslinking of pectin polymers. Inhibition and recovery of proton release upon boron withdrawal and restitution in plant culture medium demonstrated boron involvement in membrane processes. Rapid boron-induced changes in membrane function could be attributed to boron-complexing membrane constituents. Boron may affect metabolic pathways by binding apoplastic proteins to cis-hydroxyl groups of cell walls and membranes, and by interfering with manganese-dependent enzymatic reactions. In addition, boron has been implicated in counteracting toxic effects of aluminum on root growth of dicotyledonous plants. Molecular investigations of boron nutrition have been initiated by the discovery of a novel mutant of Arabidopsis thaliana with an altered requirement for boron.

In this study, fruits, fruit flesh and seeds of Rosa damascena and Rosa canina were assayed for the composition of fatty acids, ascorbic acid, alpha-tocopherol, beta-carotene, and mineral elements. The concentration of linoleic acid in seed oil of R. damascena (54.18%) was higher than in R. canina (48.84%). Alpha-tocopherol concentrations were found to be 7.10 microg/g and 34.20 microg/g for R. damascena and R. canina fruits, respectively. Ascorbic acid conc. was determined as the highest in the fruit flesh (546 mg/100 g in R. damascena and 2,200 mg/100 g in R. canina), and as the lowest in the seeds of both species. R. damascena fruits were found to be richer in minerals such as Ca, Fe, K, Mn, Na, P, and Zn than R. canina fruits. The results of the present study showed that R. damascena fruits could be used as food and food additive equally as rose hip fruits.

A wide diversity of biological molecules are modified by the addition of sugar residues, and a large number of glycosyltransferases have been identified that are responsible for these reactions. Despite catalyzing closely related reactions, many of these transferases show little apparent sequence homology. By comparing two apparently unrelated families of yeast Golgi mannosyltransferases a short motif containing two aspartate residues was observed that was conserved in both groups of proteins. Mutagenesis of one of the members of these families, the alpha-1,3-mannosyltransferase Mnn1p, showed that altering either of these aspartates eliminates all enzymatic activity. These changes do not appear to affect the overall folding and assembly of Mnn1p. A similar aspartate-containing sequence was found to be conserved in a diverse range of other glycosyltransferase families, much more frequently than would be expected by chance, suggesting that it is a feature of the catalytic site, or an element of a structural fold, shared by many glycosyltransferases

Coeliac disease is an autoimmune gluten-sensitive entheropathy. The only available treatment for it is the life-long adherence to a gluten-free diet although these products are often poor in proteins, minerals, and vitamins. The current study was designed to investigate the effect of buckwheat flour incorporation to a gluten-free experimental formulation on the size-related parameters, and microelements and proteins contents. Buckwheat flour affected positively the technological quality of bread, like bread specific volume index and loaf size. Increasing concentration of buckwheat flour (10-40%) in bread affected the proportional enrichment in proteins and microelements, especially in copper and manganese.

Indian mustard (Brassica juncea L.), a high biomass crop plant, accumulated substantial amounts of cadmium, with bioaccumulation coefficients (concentration of Cd in dry plant tissue/concentration in solution) of up to 1100 in shoots and 6700 in roots at nonphytotoxic concentrations of Cd (0.1 micrograms/mL) in solution. This was associated with a rapid accumulation of phytochelatins in the root, where the majority of the Cd was coordinated with sulfur ligands, probably as a Cd-54 complex, as demonstrated by x-ray absorption spectroscopy. In contrast, Cd moving in the xylem sap was coordinated predominantly with oxygen or nitrogen ligands. Cd concentrations in the xylem sap and the rate of Cd accumulation in the leaves displayed similar saturation kinetics, suggesting that the process of Cd transport from solution through the root and into the xylem is mediated by a saturable transport system(s). However, Cd translocation to the shoot appeared to be driven by transpiration, since ABA dramatically reduced Cd accumulation in leaves. Within leaves, Cd was preferentially accumulated in trichomes on the leaf surface, and this may be a possible detoxification mechanism

Four sequential extraction procedures (Sposito, Tessier, Silveira and Bureau Communautaire de Reference (BCR)) were used to evaluate the distribution of some metals (Fe, Cu, Cd and Zn) in a contaminated soil around a mining area. The results showed that Fe and Zn were mainly recovered in the recalcitrant soil fractions, while Cd was primarily localized in the exchangeable fraction. Soil Cu was highly associated with organic matter fraction. The amorphous Fe fraction in Silveira could be recognized as part of the Fe-Mn oxide fraction in Tessier and BCR procedures, while the crystalline Fe oxide fraction was classified into the residual fraction in Sposito, BCR and Tessier schemes. Although the same reagent was used to extract target fraction, less carbonate-bound Cu, Cu and Zn were extracted in Tessier procedure as compared to Silveira method, while Tessier scheme yielded a higher proportion of Fe, Cu and Zn in the Fe-Mn oxide fraction than BCR method. Due to the lack of uniformity of experimental conditions and the differences in extraction reagents, the extraction efficiency of metal species varied with the sequential extraction schemes. Therefore, care should be taken when comparing the results obtained by different sequential extraction procedures.