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The article discusses a study regarding the preparation and application of adamantylzinc bromides to cross-coupling reaction with the presence of zinc chloride (ZnCl2). Topics include the use of 1-bromoadamantane and zinc (Zn) in the study, analyzing iodine with gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS), and the presence of heteroaromatic acid chlorides during the preparation of aryl adamantyl ketones.

Heavy metals are ubiquitous in nature, thus constituting a serious environmental problem in many countries. Due to their toxicity, there is an obvious need to determine them at trace levels. Zinc is essential for many cellular processes, including DNA synthesis, transcription, and translation, but excess can be toxic. To analyze the uptake and metabolism of zinc in Escherichia coli , a high affinity FRET (Fluorescence Resonance Energy Transfer)–based nanosensor was developed using the cyanobacterial metallothionein SmtA flanked by CFP (cyan fluorescent protein) and YFP (yellow fluorescent protein). The chimeric sensor protein was expressed in E. coli BL21 (DE3) and purified by affinity chromatography. Following binding of zinc, FRET ratio increased with increasing the Zn 2+ concentration. Affinity mutants were constructed with binding constants ranging from 50 μM to 1 mM. In vitro analysis with bacterially purified sensor showed that it is specific for Zn 2+ and responds only weakly to Cd 2+ with no response for other biological metal ions. Moreover, the sensor activity in vitro was stable with extreme changes in pH. In vivo analysis of nanosensor response in E. coli showed that free Zn 2+ accumulate in the bacterial cells and is slowly metabolized. [ABSTRACT FROM AUTHOR]

Purpose: Zinc is an important trace element with catalytic and defensive functions. We assessed the impact of zinc deficiency in patients with end-stage liver disease awaiting liver transplantation. Methods: Serum zinc levels were measured at the time of evaluation for liver transplantation ( n = 368). Patients were dichotomized in two groups based on low and normal zinc serum levels. Results: Serum zinc levels are tightly associated with liver function as patients with low zinc levels ( n = 226) had a higher Model for End-Stage Liver Disease (MELD) score (15.0 [5.0-40.0]) than patients with normal zinc ( n = 142) levels (9.0 [6.0-34.0]; p < 0.00). Multivariate analysis demonstrated that serum zinc levels function as an independent predictor of hepatic decompensation (hydropic decompensation: odds ratio [OR] 0.82; 95 % confidence interval [CI] 0.70-0.96; p = 0.015; hepatic encephalopathy: OR 0.80; 95 % CI 0.71-0.90; p = 0.000; spontaneous bacterial peritonitis: OR 0.85; 95 % CI 0.72-1.00; p = 0.047; hepatorenal syndrome: OR 0.83; 95 % CI 0.72-0.95; p = 0.011). Actuarial survival free of liver transplantation was reduced for low-zinc patients (26.7 ± 4.0 months; 95 % CI 18.8-34.6) compared to patients with normal zinc levels (30.9 ± 3.0 months; 95 % CI 24.9-36.9; p = 0.008). Reduction of zinc levels for patients on the transplantation list resulted in a 28.3-fold increased risk of death/liver transplantation (95 % CI 3.2-244.8, p < 0.001). Conclusions: Serum zinc levels are associated with reduced survival in end-stage liver disease patients. Whether or not zinc supplementation might be beneficial for patients on a liver transplantation list requires further study. [ABSTRACT FROM AUTHOR]

The aim of the study was to determine total antioxidative capacity (TAC) and zinc concentration in serum of dogs suffering from perianal tumours just before the start of the antihormonal treatment (AHT) and one and six months later. The study was performed on 45 dogs divided into two groups: control group suffering from non-malignant tumours (N = 24) and a group with malignant neoplastic changes (N = 21). Serum TAC and zinc concentrations were measured using photometric and atomic absorption spectrophotometric methods. Six months after the start of the AHT, TAC was significantly lower by 10.6% in dogs with malignant tumours when compared to controls (P = 0.03). In the non-malignant group, serum zinc concentration was higher before the treatment than in the malignant group, while the opposite results were observed six months later (P < 0.001). In the non-malignant group, gradually decreasing values of serum zinc concentration at each stage of the investigation were observed, while the opposite results were obtained in the malignant group (P < 0.05). The obtained results indicate that malignant neoplastic process is associated with significantly reduced TAC. Determination of serum zinc concentration in dogs with non-malignant and malignant perianal tumours may have practical diagnostic and prognostic values and may serve towards increasing the effectiveness of AHT monitoring. [ABSTRACT FROM AUTHOR]

In the solid state each of three binuclear zinc dithiocarbamates bearing hydroxyethyl groups, {Zn[S 2 CN(R)CH 2 CH 2 OH] 2 } 2 for R = iPr ( 1 ), CH 2 CH 2 OH ( 2 ), and Me ( 3 ), and an all alkyl species, [Zn(S 2 CNEt 2 ) 2 ] 2 ( 4 ), features a centrosymmetric {ZnSCS} 2 core with a step topology; both 1 and 3 were isolated as monohydrates. All compounds were broadly cytotoxic, specifically against human cancer cell lines compared with normal cells, with greater potency than cisplatin. Notably, some selectivity were indicated with 2 being the most potent against human ovarian carcinoma cells (cisA2780), and 4 being more cytotoxic toward multidrug resistant human breast carcinoma cells (MCF-7R), human colon adenocarcinoma cells (HT-29), and human lung adenocarcinoma epithelial cells (A549). Based on human apoptosis PCR-array analysis, caspase activities, DNA fragmentation, cell apoptotic assays, intracellular reactive oxygen species (ROS) measurements and human topoisomerase I inhibition, induction of apoptosis in HT-29 cells is demonstrated via both extrinsic and intrinsic pathways. Compounds 2 – 4 activate the p53 gene while 1 activates both p53 and p73. Cell cycle arrest at the S and G 2 /M phases correlates with inhibition of HT-29 cell growth. Cell invasion is also inhibited by 1 – 4 which is correlated with down-regulation of NF -κ B. [ABSTRACT FROM AUTHOR]

The results of the analysis of thermal stability for zinc (II) and boron (III) complexes with 3,3′,5,5′-tetramethyl-4-ethyl-4′-iodo-2,2-dipyrrin [HL 1 ], 3,3′-diamyl-4,4′-dimethyl-5,5′-dibromo-2,2′-dipyrrin [HL 2 ] and 3,3′,5,5′-tetramethyl-4,4′-dibromo-2,2′-dipyrrin [HL 3 ] of the composition [Zn(L 1 ) 2 ]–[Zn(L 3 ) 2 ] and [BF 2 L 1 ]–[BF 2 L 3 ] are presented. The influence of halogenation of dipyrrin ligand is manifested in decreasing thermal stability of [Zn(L) 2 ] and [BF 2 L] when replacing 4,4′-dibromosubstituted dipyrrin on 5,5′-dibromo- or 4-monoiodosubstituted ligand. Intramolecular red-ox-reactions with participation of halogen atoms are the main cause of thermal stability lowering of dipyrrinates [Zn(L) 2 ] and [BF 2 L] compared with alkylsubstituted analogs. The obtained results are interesting for the development of laser dyes and sensors for PDT. [ABSTRACT FROM AUTHOR]

Reduction of a variety of extremely bulky amido Group 12 metal halide complexes, [LMX(THF)0,1] (L=amide; M=Zn, Cd, or Hg; X=halide) with a magnesium(I) dimer gave a homologous series of two-coordinate metal(I) dimers, [L′MML′] (L′=N(Ar†)(SiMe3), Ar†=C6H2{C(H)Ph2}2Pri-2,6,4); and the formally zinc(0) complex, [L*ZnMg(MesNacnac)] (L*=N(Ar*)(SiPri3); Ar*=C6H2{C(H)Ph2}2Me-2,6,4; MesNacnac=[(MesNCMe)2CH]−, Mes=mesityl), which contains the first unsupported ZnMg bond. Two equivalents of [L*ZnMg(MesNacnac)] react with ZnBr2 or ZnBr2(tmeda) to give the mixed valence, two-coordinate, linear tri-zinc complex, [L*ZnIZn0ZnIL*], and the first zinc(I) halide complex, [L*ZnZnBr(tmeda)], respectively. The analogues [L*ZnMZnL*] (M=Cd or Hg), were also prepared, the Cd species contains the first ZnCd bond in a molecular compound. Metal-metal bonding was studied by DFT calculations. [ABSTRACT FROM AUTHOR]

The preparation and characterization of a series of 8-hydroxyquinoline ligands and their complexes with Ti(iv), Al(iii) and Zn(ii) centres is presented. The complexes are characterized using NMR spectroscopy, elemental analysis and, in some cases, by single crystal X-ray diffraction experiments. The complexes are compared as initiators for the ring-opening polymerization of racemic-lactide; all the complexes show moderate/good rates and high levels of polymerization control. In the case of the titanium or aluminium complexes, moderate iso-selectivity is observed (Pi = 0.75), whereas in the case of the zinc complexes, moderate hetero-selectivity is observed (Ps = 0.70). [ABSTRACT FROM AUTHOR]

Total dissolved zinc (Zn) and its speciation was investigated by cathodic stripping voltammetry (CSV) in the western North Pacific and its marginal seas, the Sea of Okhotsk and the Sea of Japan (East Sea). In these high latitude areas, Zn complexing ligands in most samples were saturated with zinc because of the high dissolved Zn concentration. Relatively high total ligand concentrations (C L ) and relatively low conditional stability constants ( K Z n L , Z n 2 + ′ ) have been obtained in the surface waters of the Sea of Okhotsk (C L = 2.6 nM, log K Z n L , Z n 2 + ′ = 9.5) and the Sea of Japan (East Sea) (C L = 1.3 nM, log K Z n L , Z n 2 + ′ = 9.1) compared with those in the open ocean (subtropical and subarctic North Pacific, C L = 0.2–1.2 nM, log K ' Z n L , Z n 2 + = 9.1–10.8). The fraction of Zn labile in the deep waters of the Sea of Okhotsk was relatively small (34–38%, > 1479 m), which might indicate the presence of high concentrations of Zn complexing ligands in deep waters of the Sea of Okhotsk. In the western North Pacific, positive relationships were obtained between total ligand and chlorophyll a concentrations, suggesting that Zn complexing ligands in the surface water might be derived from bacteria and phytoplankton in the western North Pacific. However, relatively high concentrations of the ligands exist in low chlorophyll- a surface water in the Sea of Okhotsk and the Sea of Japan (East Sea), implying that Zn complexed ligands in those marginal seas have a different origin. [ABSTRACT FROM AUTHOR]

Nickel and zinc salen complexes were simultaneously encapsulated in the supercages of the mesoporous zeolite A by using the flexible ligand method. This heterogeneous catalyst NiZnsalenA was characterized by X-ray diffraction, infrared spectroscopy, diffuse reflectance UV-vis spectroscopy, elemental analysis, and N adsorption/desorption experiments. The techniques of cyclic voltammetry (CV) and chronoamperometry (CA) were employed to investigate the electrochemical behavior and electrocatalytic activity toward the oxidation of methanol on NiZnsalenA glassy carbon electrode (GCE) in 0.1-M NaOH solution. The CV results presented a pair of redox peaks associated with the Ni(salen)(OH)/Ni(salen)O(OH) redox couple. NiZnsalenA also showed the superior electrocatalytic activity to the oxidation of methanol than pure Ni-modified electrode, mainly due to a synergetic effect in NiZnsalenA. This synergetic effect may originate from the interaction of Ni(salen) and Zn(salen) and/or the formation of dinuclear salen complexes via the lattice oxygen of the zeolitic host. The effects of the scan rate, methanol concentration, and OH concentration on methanol oxidation are investigated, and a possible mechanism is proposed that the oxidation of methanol is done by reaction with Ni(salen)O(OH) and also direct electrooxidation reaction. The kinetic parameters such as the electron transfer coefficient α and the rate constant k of the electrode reaction were estimated to be 0.39 and 1.59 s, respectively. In both the CA and CC studies, the process of methanol oxidation followed a Cottrellian behavior, and the diffusion coefficients D and D of methanol represented the similar tendency, where an initial sharp drop was terminated to a very slow change as the concentration of methanol was approaching 0.7 M. The catalytic rate constant k increased rapidly until the concentration of methanol was increased above 0.7 M, and then the values of k remained almost constant. [ABSTRACT FROM AUTHOR]

Genetic diversity among 80 irrigated bread wheat genotypes was studied for their grain’s protein, iron and zinc concentrations as well as agronomic traits. The trend of these traits over the 70 years of cultivar releasing was demonstrated. The experiment was conducted as a RCBD with three replicates under normal and terminal drought stress conditions in Kermanshah, Iran during 2011–2012 cropping season. The results of combined ANOVA revealed high significant genotypic differences for all traits, except grain iron and zinc yield. Terminal drought stress reduced all studied traits except grain iron concentration which it increased by 14.10%. The maximum effect of drought stress was on grain zinc yield, grain yield and thousand grain weight as much as 26.65, 23.48 and 18% reduction, respectively. In both conditions, there were negative correlations among grain yield and grain iron, zinc and protein concentrations. Moreover, it was found that grain yield was increased with a small improvement during 70 years while protein, iron and zinc concentrations were decreased over the years. A wide range of genetic diversity in micronutrients uptake, particularly iron and zinc within studied wheat genotypes was identified which suggesting that selection for improved micronutrients efficiency is possible. What was concluded from this study is breeders’ attention to enhancing grain production caused to neglect the quality of wheat production specially protein, iron and zinc concentrations during the last 70 years. [ABSTRACT FROM AUTHOR]

Complexes of Mg, Ca and Zn based on sterically hindered 4- tert -butyl-2,6-bis(diphenylmethyl)phenol were synthesized and tested as catalysts of ring-opening polymerization of ɛ-caprolactone and rac -lactide. [ABSTRACT FROM AUTHOR]

Thermoalkalophilic lipases are prone to aggregation from their dimer interface to which structural zinc is very closely located. Structural zinc sites have been shown to induce protein aggregation, but the interaction between zinc and aggregation tendency in thermoalkalophilic lipases remains elusive. Here we delineate the interplay between zinc and aggregation of the lipase from Bacillus thermocatenulatus (BTL2), which is taken to be a representative of thermoalkalophilic lipase. Results showed that zinc removal disrupted the BTL2 dimer, leading to monomer formation and reduced thermostability manifesting as a link between zinc and dimerization that leads to thermostability, while zinc addition induced aggregation. Biochemical and kinetic characterizations of zinc-induced aggregates showed that the aggregates obtained from the early and late stages of aggregation had differential characteristics. In the early stages, the aggregates were soluble and possessed native-like structures, while in the late stages, the aggregates became insoluble and showed fibrillar characteristics with binding affinities for Congo red and thioflavin T. The impact of temperature on zinc-induced aggregation was further investigated, and it was found that the native-like early aggregates could completely dissociate into functional lipase forms at high temperatures while dissociation of the late aggregates was limited. To this end, we report that the zinc-induced aggregation of BTL2 can be reversed by temperature switches and initiated by ordered aggregates in the early stages that gain fibrillar-like features over time. Insights revealed by this work contributes to the knowledge of aggregation mechanisms that exist in thermophilic proteins, reflecting the potential use of metal addition and/or removal to fine-tune aggregation tendency. [ABSTRACT FROM AUTHOR]

A series of nanoporous carbon supported Pd–Zn catalysts (Pd x Zn/NPC, x = 1, 2, 3) have been successfully prepared via impregnation-reduction method and firstly employed as anode catalysts for direct borohydride-hydrogen peroxide fuel cell (DBHFC). The properties of the Pd x Zn/NPC electrocatalysts are characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), cyclic voltammetry (CV), chronoamperometry (CA) and single fuel cell test. The TEM images of Pd 2 Zn/NPC catalyst reveal that the metal particles with a size of approximately 3.1 nm are uniformly dispersed on the nanoporous carbon (NPC). Besides, all the Pd x Zn/NPC catalysts exhibit enhanced catalytic activity and stability for BH 4 − electrooxidation compared to monometallic Pd/NPC in the electrochemical tests. Especially, the Pd 2 Zn/NPC catalyst exhibits the highest electrocatalytic activity toward borohydride oxidation among the four catalysts. Moreover, the DBHFC equipped with the Pd 2 Zn/NPC anode also presents an excellent cell performance with the maximum power density as high as 103.93 mW cm −2 at 25 °C. [ABSTRACT FROM AUTHOR]

In this paper, we synthesized of pure ZnO and ZnO doped with SnO nanophotocatalyst by sol gel method. The successful synthesis of ZnO nanopowders was evident by XRD lines. Furthermore SnO were well incorporated into the ZnO crystal lattice in doped sample. Scanning electron microscope (SEM) analysis revealed that the SnO were well incorporated into the ZnO crystal lattice. The photocatalytic activities of these materials were investigated for Sodium alkyl benzene sulfonate removal from aqueous solution under UV light irradiation. It was shown that the use of ZnO/SnO as photocatalyst have better photocatalytic activity for degradation of Sodium alkyl benzene sulfonate than ZnO. The effects of initial concentration of surfactant, catalyst loading, pH, addition of oxidant on the reaction rate were ascertained and optimum conditions for maximum degradation was determined. [ABSTRACT FROM AUTHOR]

The aim of this study was to examine the capacity of anionic resins to remove zinc as zinc chloride complexes in fixed bed. The applicability of the kinetics models and the characteristics of the bed (sorption capacity, breakthrough curve, depth of the adsorption zone) were taken into account. The influence of the process parameters, such as resin quantity (bed height) and zinc initial concentration, on the removal process was also considered. The obtained results (Amberlite IRA410) were analyzed using sorption kinetic models such as Thomas, Adam-Bohart, and Clark, by linear regression analysis. Similarly, the concept of the mass transfer zone was applied in order to properly design the fixed bed adsorption process. By comparing various resins, the following series was depicted based on sorption capacities: Amberlite IRA410 > Purolite A103S > Purolite NRW700 > Purolite A400MBOH. The experimental data were in good agreement with the Clark model, while for the other models, lower correlation coefficients were obtained under the same experimental conditions. The MTZ height and rate of movement increased with increasing initial concentration. [ABSTRACT FROM AUTHOR]

Objective: Evidence from mouse models suggests that zinc-α2-glycoprotein (ZAG) is a novel anti-obesity adipokine. In humans, however, data are controversial and its physiological role in adipose tissue (AT) remains unknown. Here we explored the molecular mechanisms by which ZAG regulates carbohydrate metabolism in human adipocytes. Methods: ZAG action on glucose uptake and insulin action was analyzed. β1 and β2-adrenoreceptor (AR) antagonists and siRNA targeting PP2A phosphatase were used to examine the mechanisms by which ZAG modulates insulin sensitivity. Plasma levels of ZAG were measured in a lean patient cohort stratified for HOMA-IR. Results: ZAG treatment increased basal glucose uptake, correlating with an increase in GLUT expression, but induced insulin resistance in adipocytes. Pretreatment of adipocytes with propranolol and a specific β1-AR antagonist demonstrated that ZAG effects on basal glucose uptake and GLUT4 expression are mediated via β1-AR, whereas inhibition of insulin action is dependent on β2-AR activation. ZAG treatment correlated with an increase in PP2A activity. Silencing of the PP2A catalytic subunit abrogated the negative effect of ZAG on insulin-stimulated AKT phosphorylation and glucose uptake but not on GLUT4 expression and basal glucose uptake. ZAG circulating levels were unchanged in a lean patient cohort stratified for HOMA-IR. Neither glucose nor insulin was associated with plasma ZAG. Conclusions: ZAG inhibits insulin-induced glucose uptake in human adipocytes by impairing insulin signaling at the level of AKT in a β2-AR- and PP2A-dependent manner. [ABSTRACT FROM AUTHOR]

Heat shock protein 33 (Hsp33) is activated in the presence of HO by a very interesting redox switch based on a tetra-coordinated zinc-cysteine complex present in the fully reduced and inactive protein form. The oxidation of this zinc center by HO induces formation of two S-S bridges and the zinc release followed by the protein unfolding. We report here a theoretical study of the step-by-step sequence of the overall process starting with the oxidation of the first cysteine residue and ending with the zinc release. Each reaction step is characterized by its Gibbs free energy barrier (∆ G). It is predicted that the first reaction step consists in the oxidation of Cys263 by HO which is by far the most reactive cysteine (∆ G = 15.4 kcal mol). The next two reaction steps are the formation of the first S-S bridge between Cys263 and Cys266 (∆ G = 13.6 kcal mol) and the oxidation of Cys231 by HO (∆ G = 20.4 kcal mol). It is then shown that the formation of the second S-S bridge (Cys231-Cys233) before the zinc release is most unlikely (∆ G = 34.8 kcal mol). Instead, the release of zinc just after the oxidation of the third cysteine (Cys231) is shown to be thermodynamically (dissociation Gibbs free energy ∆ G = 6.0 kcal mol) and kinetically (reaction rate constant k ≈ 10 s) favored. This result is in good agreement with the experimental data on the oxidation mechanism of Hsp33 zinc center available to date. [ABSTRACT FROM AUTHOR]

Between 5 and 10% of all proteins of a given organism are estimated to require zinc for function, and hence zinc is essential for almost any given metabolic process. It is therefore of great interest to understand major players and mechanisms that ensure the tight and correct control of zinc distribution and speciation in organisms and their individual cells. Significant progress has been made in recent years regarding 3-dimensional structures and modes of action of zinc sensor proteins, membrane-bound zinc transporters for cellular and sub-cellular uptake and efflux, as well as intracellular binding proteins. This feature article highlights advances in structures, zinc-binding sites and thermodynamics of proteins that are involved in zinc homeostasis and trafficking, including developments in understanding the metal selectivity of proteins. [ABSTRACT FROM AUTHOR]

Nanowires were grown by means of a novel aerosol-based method called Aerotaxy. Here an aerosol of Au catalyst nanoparticles in N 2 is mixed with MOVPE precursors in a flow-through reactor at atmospheric pressure, whereby nanowires are produced continuously in high concentrations. We demonstrate the possibility of in situ doping of the NWs and the realization of well-controlled p-type GaAs nanowires using this Aerotaxy method. By controlling the cracking and concentration of the precursors, p-doped GaAs nanowires could be grown exhibiting a wide range of Zn doping levels. DEZn was used as the dopant source and the injected DEZn/TMGa ratio was varied from 0.1% to 3.4%. The morphology, the crystalline structure and the composition of the nanowires were studied using SEM, TEM and XEDS. The nanowires were grown straight without any significant tapering and this ideal morphology could be maintained up to an injected DEZn/TMGa ratio of 3.4%. The nanowires typically grew in the 〈111〉 direction with a pure zincblende structure, but by increasing the DEZn flow the number of twinning defects increased which we ascribe to Zn incorporation. Elemental analysis shows a high Zn content in the catalyst particle and also a gradient in the Zn content along the nanowire. The samples were analyzed optically using photoluminescence (PL). From the result we estimated the free hole concentration induced by Zn acceptors to be 1×10 20 cm −3 for DEZn/TMGa ratio of 3.4%. To our knowledge this is the first report on in situ doping of GaAs nanowires grown by Aerotaxy. [ABSTRACT FROM AUTHOR]

Objective Few studies of maternal prenatal diet and child development examine micronutrient status in relation to fetal assessment. Methods Twenty-four-hour dietary recall of zinc and folate and 20 min of fetal heart rate were collected from 3rd trimester pregnant adolescents. Results Deficient zinc was associated with less fetal heart rate variability. Deficient folate had no associations with HRV. Neither deficient zinc nor deficient folate was related to fetal heart rate. Conclusions These findings, from naturalistic observation, are consistent with emerging data on prenatal zinc supplementation using a randomized control design. Practical Implication Taken together, the findings suggest that maternal prenatal zinc intake is an important and novel factor for understanding child ANS development. [ABSTRACT FROM AUTHOR]

We propose a technique of on-site quantitative analysis of Zn2+ in aqueous solution based on the combination of electrodeposition for preconcentration of Zn onto a Cu electrode and successive underwater laser-induced breakdown spectroscopy (underwater LIBS) of the electrode surface under electrochemically controlled potential. Zinc emission lines are observed with the present technique for a Zn2+ concentration of 5 ppm. It is roughly estimated that the overall sensitivity over 10 000 times higher is achieved by the preconcentration. Although underwater LIBS suffers from the spectral deformation due to the dense plasma confined in water and also from serious shot-to-shot fluctuations, a linear calibration curve with a coefficient of determination R² of 0.974 is obtained in the range of 5-50 ppm. [ABSTRACT FROM AUTHOR]

Inductively coupled plasma mass spectrometry (ICP-MS) procedures with isotope dilution were established for the accurate determination of trace Zn (in the level of 10−4 to 10−5 g g−1) in several tens of mg of geological and cosmochemical rock samples. Zinc was determined by 66Zn/67Zn and 68Zn/67Zn ratios with the use of an enriched isotope, i.e.67Zn. Among possible interferences for Zn isotopes (66Zn, 67Zn and 68Zn), molecular ions from ambient gases and sample solutions were found to be negligibly small, whereas doubly charged Ba ions (132Ba2+, 134Ba2+ and 136Ba2+) potentially interfered with the three Zn isotopes concerned. Either such interferences were eliminated by chemical separation in the matrix-separation ICP-MS procedure or they were mathematically corrected in the ICP-MS procedure without matrix separation. The three analytical procedure studies were evaluated in terms of analytical capability and data quality. [ABSTRACT FROM AUTHOR]

Three new zinc compounds {[Zn 2 (ccop) 2 (4,4′-bpy)]·H 2 O} n ( 1 ), {[Zn(ccop)(bpp)]·H 2 O} n ( 2 ) and [Zn(ccop)(H 2 O) 5 ]·H 2 O ( 3 ) (H 2 ccop = 5-carboxyl-1-carboxymethyl-2-oxidopyridinium, 4,4′-bpy = 4,4′-bipyridine, bpp = 1,3-bis(4-pyridyl) propane) have been prepared under hydrothermal conditions at different pH values, and characterized by elemental analysis, IR spectra, thermogravimetric analysis, powder X-ray diffraction, and single-crystal X-ray diffraction. Complex 1 features a 2D (4,4) net when the dinuclear [Zn 2 (COO) 2 N 2 O 2 ] unit is regarded as a quadruply-connected node. Complex 2 also displays a 2D (4,4) net constructed by Zn-carboxylate chains and bpp struts. While 3 is a mononuclear complex which is further assembled into a 3D supramolecular structure through hydrogen boning interactions. All of 1–3 emit the intense indigotin photoluminescence at room temperature in solid state. [ABSTRACT FROM AUTHOR]

The structural stability of thermoelectric materials is a subject of growing importance for their energy harvesting applications. Here, we study the microscopic mechanisms governing the structural stability change of zinc antimony at its working temperature, using molecular dynamics combined with experimental measurements of the electrical and thermal conductivity. Our results show that the temperature-dependence of the thermal and electrical transport coefficients is strongly correlated with a structural transition. This is found to be associated with a relaxation process, in which a group of Zn atoms migrates between interstitial sites. This atom migration gradually leads to a stabilizing structural transition of the entire crystal framework, and then results in a more stable crystal structure of ß-Zn4Sb3 at high temperature. [ABSTRACT FROM AUTHOR]

Functionalized phenolic monomers have been generated and isolated from an organosolv lignin through a two-step depolymerization process. Chemoselective catalytic oxidation of β-O-4 linkages promoted by the DDQ/ tBuONO/O2 system was achieved in model compounds, including polymeric models and in real lignin. The oxidized β-O-4 linkages were then cleaved on reaction with zinc. Compared to many existing methods, this protocol, which can be achieved in one pot, is highly selective, giving rise to a simple mixture of products that can be readily purified to give pure compounds. The functionality present in these products makes them potentially valuable building blocks. [ABSTRACT FROM AUTHOR]

Reaction of Zn(C6F5)2·toluene (two equivalents) with 1,3-dipropoxy-p-tert-butyl-calix[4]arene (L¹H2) led to the isolation of the complex [{Zn(C6F5)}2L¹] (1), whilst similar use of Zn(Me)2 resulted in the known complex [{Zn(Me)}2L¹] (2). Treatment of L¹H2 with in situ prepared Zn{N(SiMe3)2}2 in refluxing toluene led to the isolation of the compound [(Na)ZnN(SiMe3)2L¹] (3). The stepwise reaction of L¹H2 and sodium hydride, followed by ZnCL² and finally NaN(SiMe3)2 yielded the compound [Zn{N(SiMe3)2}2L¹] (4). The reaction between three equivalents of Zn(C6F5)2·toluene and oxacalix[3]arene (L²H3) at room temperature formed the compound {[Zn(C6F5)]3L²} (5); heating of 5 in acetonitrile caused the ring opening of the parent oxacalix[3]arene and rearrangement to afford the complex [(L²)Zn6(C6F5)(R)(RH)OH]·5MeCN R = C6F5CH2-(p-tBuPhenolate-CH2OCH2-)2-p-tBuPhenolate-CH2O-)3- (6). The molecular structures of the new complexes 1, 3 and 6, together with that of the known complex 2, whose solid state structure has not previously been reported, have been determined. Compounds 1, 3-5 have been screened for the ring opening polymerization (ROP) of ∊-caprolactone (∊-CL) and rac-lactide. Compounds featuring a Zn-C6F5 fragment were found to be poor ROP pre-catalysts as they did not react with benzyl alcohol to form an alkoxide. By contrast, compound 4, which contains a zinc silylamide linkage, was the most active of the zinc-based calix[4]arene compounds screened and was capable of ROP at ambient temperature with 65% conversion over 4 h. [ABSTRACT FROM AUTHOR]

Based on first-principles calculations and thermodynamic stability analysis, we find that 3 and 3 could be synthesized under restricted condition, as their bulk phases are stable in a limited chemical potential range with respect to the competing phases. It is also found that 3 and 3 are unstable under thermodynamic equilibrium conditions. Electronic structure calculations suggest that the hybridization between TM (transition metal) and O could play important roles for magnetoelectric properties in the 3 (X = Mn, Zn, Fe), while the hybridization between Sn and O dominates in 3. [ABSTRACT FROM AUTHOR]

Understanding the crystal structure and electronic states of the organic semiconductor is of fundamental importance for developing the materials for the organic electronics. However, the theoretical treatment of organic semiconductors remains challenging, as the semilocal density functional theory fails to describe the dispersion forces accurately. We use van der Waals inclusive density functionals to study the zinc phthalocyanine polymorphs. It is found that the structure and energetics are well described with the van der Waals density functional, and as a result, the electronic band structure is nicely reproduced. Furthermore, we reveal that the distance between the molecules and the molecule tilt angle are important factors that determine the electronic band dispersion. [ABSTRACT FROM AUTHOR]

Sorption of Cu(II) and Zn(II) on three natural clays meeting the international requirements for use as liners was evaluated by means of batch tests. The purpose of this research was to determine the retention capacities of the clays for metal cations commonly present in urban solid waste leachates. The pH and ionic strength conditions were set at values frequently found in real leachates. The changes observed in the XRD patterns and FTIR spectra upon adsorption can be considered an evidence of clay–metal electrostatic interaction. The Langmuir model was found to best describe the sorption processes, offering maximum sorption capacities from 8.16 to 56.89 mg/g for Cu(II) and from 49.59 to 103.83 mg/g for Zn(II). All samples remove more Zn(II) than Cu(II), which may be related to the different geometry of the hydrated Cu(II) cation. The total amount of metal sorption was strongly influenced by the total specific surface area, the presence of carbonates and the smectite content of the clays. In addition to their known quality as physical barriers, the adsorbed amounts obtained indicate the suitability of the tested clays to contribute to the retardation of Cu(II) and Zn(II) transport through clay liners. [ABSTRACT FROM AUTHOR]

This paper presents the first report providing information on the zinc (Zn) biosorption potentialities of the purple non-sulfur bacterium Rhodobacter capsulatus. The effects of various biological, physical, and chemical parameters on Zn biosorption were studied in both the wild-type strain B10 and a strain, RC220, lacking the endogenous plasmid. At an initial Zn concentration of 10 mg·L−1, the Zn biosorption capacity at pH 7 for bacterial biomass grown in synthetic medium containing lactate as carbon source was 17 and 16 mg Zn·(g dry mass)-1 for strains B10 and RC220, respectively. Equilibrium was achieved in a contact time of 30-120 min, depending on the initial Zn concentration. Zn sorption by live biomass was modelled, at equilibrium, according to the Redlich-Peterson and Langmuir isotherms, in the range of 1-600 mg Zn·L−1. The wild-type strain showed a maximal Zn uptake capacity ( Qm) of 164 ± 8 mg·(g dry mass)−1 and an equilibrium constant ( Kads) of 0.017 ± 0.00085 L·(mg Zn)−1, compared with values of 73.9 mg·(g dry mass)−1 and 0.361 L·mg−1 for the strain lacking the endogenous plasmid. The Qm value observed for R. capsulatus B10 is one of the highest reported in the literature, suggesting that this strain may be useful for Zn bioremediation. The lower Qm value and higher equilibrium constant observed for strain RC220 suggest that the endogenous plasmid confers an enhanced biosorption capacity in this bacterium, although no genetic determinants for Zn resistance appear to be located on the plasmid, and possible explanations for this are discussed. [ABSTRACT FROM AUTHOR]

Methyl 131-(di)cyanomethylene-pyropheophorbides were synthesized by Knoevenagel reactions of the corresponding 131-oxo-chlorins prepared from modifying chlorophyll- a with malononitrile or cyanoacetic acid. Alternatively, methyl 131-cyanomethylene-pyropheophorbides were produced by Wittig reactions of 131-oxo-chlorins with Ph3P= CHCN. Self-aggregation of zinc complexes of the semi-synthetic chlorophyll derivatives possessing a hydroxy or methoxy group at the 31-position was examined in 1%(v/v) tetrahydrofuran or dichloromethane and hexane by electronic absorption and circular dichroism spectroscopy. Although intermolecular hydrogen-bonding between the 31-hydroxy and 131-oxo groups of bacteriochlorophylls- c/ d/ e/ f was essential for their self-aggregation in natural light-harvesting antenna systems (=chlorosomes), zinc 31-hydroxy-131-di/monocyanomethylene-chlorins self-aggregated in the less/lesser polar organic solvents to form chlorosome-like large oligomers in spite of lacking the 131-oxo moiety as the hydrogen-bonding acceptor. Zinc 31-methoxy-131-dicyanomethylene-chlorin gave similar self-aggregates regardless of lack of both the 31-hydroxy and 131-oxo groups. The present self-aggregation was ascribable to stronger coordination of the 31-oxygen atom to the central zinc than the conventional systems, where the electron-withdrawing cyano group(s) increased the coordinative ability of the central zinc through the chlorin π-system. [ABSTRACT FROM AUTHOR]

Highly functionalized aldol-type products bearing a β-quaternary center and a stereoselectively controlled γ-hydroxy function are readily prepared by the diastereoselective addition of an allylic zinc reagent embedded in an isoxazole ring to various aromatic and heteroaromatic aldehydes, in the presence of Lewis acids, such as MgCl2 or LaCl3.2 LiCl. After reductive cleavage of the N-O bond by using Fe, NH4Cl, aldol-type products bearing a stereocontrolled β-quaternary center and a γ-hydroxy group were observed. The benzylic reactivity of the isoxazolylmethylzinc reagent towards other electrophiles, such as acid chlorides, aryl and allylic halides, as well as aldehydes in the presence of BF3.OEt2 are also described. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to evaluate the protective effect of zinc (Zn2+) and selenite ions (SeO32-) against cadmium ions (Cd2+)-induced changes of protein synthesis in mice organs. Material and methods: Experiments were performed with outbred 4 - 6-week-old white laboratory mice using intraperitoneal (i.p.) injections of CdCl2, ZnSO4 , and Na2SeO3 solution 3 times per week for 6 weeks. Protein synthesis was evaluated by incorporation of [14C]-labeled leucine into newly synthesized peptides and proteins. Results: General effect of used metals was assessed according to mice body weight gain and the relative weight index of organs. In respect to the control, the body weight gain of experimental mice was higher after 5 - 6 week of CdCl2 treatment. In addition, an increase in the relative weight index of the liver was revealed. The significant decrease of body weight gain in Zn2+-treated mice, as compared to the control, was obtained at only the last week of ZnSO4 administration. Zn2+ or SeO32-, administered together with Cd2+, abolished the stimulating effect of Cd2+ on mice growth. Zn2+ pretreatment also eliminated the Cd2+-induced mice liver weight alteration. Exposure to Cd2+ decreased incorporation of 14C-labeled leucine into newly synthesized peptides and proteins in liver, kidney and heart. The protein synthesis in skeletal muscle was activated by Zn2+. The pretreatment with ZnSO4 or Na2SeO3 solution provided a different protective effect of Zn2+ and SeO32- against a Cd2+-induced decrease in the intensity of protein synthesis in mice organs. Conclusion: The protective effect provided by Zn2+, against Cd2+ suppressed translation, was greater than the one provided by SeO32-. [ABSTRACT FROM AUTHOR]

Zinc deficiency is causing malnutrition for nearly one third of world populations. It is especially relevant in cereal-based diets in which low amounts of mineral and protein are present. In biological systems, Zn is mainly associated with protein. Cereal grains contain the highest Zn concentration during early developmental stage. Although hordeins are the major storage proteins in the mature barley grain and suggested to be involved in Zn binding, very little information is available regarding the Zn fertilization effects of hordein transcripts at early developmental stage and possible incorporation of Zn with hordein protein of matured grain. Zinc fertilization experiments were conducted in a greenhouse with barley cv. Golden Promise. Zn concentration of the matured grain was measured and the results showed that the increasing Zn fertilization increased grain Zn concentration. Quantitative real time PCR showed increased level of total hordein transcripts upon increasing level of Zn fertilization at 10 days after pollination. Among the hordein transcripts the amount of B-hordeins was highly correlated with the Zn concentration of matured grain. In addition, protein content of the matured grain was analysed and a positive linear relationship was found between the percentage of B-hordein and total grain Zn concentration while C-hordein level decreased. Zn sensing dithizone assay was applied to localize Zn in the matured grain. The Zn distribution was not limited to the embryo and aleurone layer but was also present in the outer part of the endosperm (sub-aleurone layers) which known to be rich in proteins including B-hordeins. Increased Zn fertilization enriched Zn even in the endosperm. Therefore, the increased amount of B-hordein and decreased C-hordein content suggested that B-hordein upregulation or difference between B and C hordein could be one of the key factors for Zn biofortification of cereal grains due to the Zn fertilization. [ABSTRACT FROM AUTHOR]

A highly selective and sensitive fluorescent Zn sensor N-(2-(benzo[d]thiazol-2-yl)phenyl)-2-((pyridin-2-ylmethyl)amino)acetamide ( 1) that derived from 2-(2′-aminophenyl)benzothiazole has been developed. In aqueous solution (HEPES/CHCN=4/6, v/v, HEPES 20 mM, pH = 7.4), sensor 1 displays highly selective recognition to Zn over other metal ions with a distinct longer-wavelength emission enhancement. Sensor 1 binds Zn through its amide form with a 1:1 binding stoichiometry, which switched on the excited-state intramolecular proton transfer (ESIPT). [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Background: The long-term health effects of coarse particular matter (PM10–2.5) are challenging to assess because of a limited understanding of the spatial variation in PM10–2.5 mass and its chemical components. Objectives: We conducted a spatially intensive field study and developed spatial prediction models for PM10–2.5 mass and four selected species (copper, zinc, phosphorus, and silicon) in three American cities. Methods: PM10–2.5 snapshot campaigns were conducted in Chicago, Illinois; St. Paul, Minnesota; and Winston-Salem, North Carolina, in 2009 for the Multi-Ethnic Study of Atherosclerosis and Coarse Airborne Particulate Matter (MESA Coarse). In each city, samples were collected simultaneously outside the homes of approximately 40 participants over 2 weeks in the winter and/or summer. City-specific and combined prediction models were developed using land use regression (LUR) and universal kriging (UK). Model performance was evaluated by cross-validation (CV). Results: PM10–2.5 mass and species varied within and between cities in a manner that was predictable by geographic covariates. City-specific LUR models generally performed well for total mass (CV R2, 0.41–0.68), copper (CV R2, 0.51–0.86), phosphorus (CV R2, 0.50–0.76), silicon (CV R2, 0.48–0.93), and zinc (CV R2, 0.36–0.73). Models pooled across all cities inconsistently captured within-city variability. Little difference was observed between the performance of LUR and UK models in predicting concentrations. Conclusions: Characterization of fine-scale spatial variability of these often heterogeneous pollutants using geographic covariates should reduce exposure misclassification and increase the power of epidemiological studies investigating the long-term health impacts of PM10–2.5. [ABSTRACT FROM AUTHOR]

Zinc (Zn) deficiency in infancy and early childhood is of public health concern in developing countries. This study aimed to longitudinally assess Zn intake of urban South Indian term infants in the first 6 months of life using measures of breast milk (BM) volume and BM Zn concentrations and, additionally, to study the effect of BM Zn intake on infant length and weight gain. BM intake by the deuterium dilution technique, BM Zn concentration at months 1, 3 and 6, as well as serum Zn level at months 3 and 6 were assessed in 50 mother-infant pairs. BM intake significantly declined from 627 mL day−1 at month 1 to 608 mL day−1 at month 6 ( P < 0.01). BM Zn concentration and intake significantly declined from month 1 to month 6 ( P < 0.001 for both). Mean infant serum Zn level at months 3 and 6 were 93.0 ± 27.1 and 99.6 ± 30.1 µg dL−1, respectively. Infant BM Zn intake at months 1 and 3 was not associated with the weight and length gain between 1-3 and 3-6 months, respectively. Zn intake from BM, maternal BM Zn content and serum Zn levels were not significantly different between small-for-gestational age and appropriate-for-gestational age infants. Therefore, among urban south Indian term infants less than 6 months of age, BM Zn intakes were low, owing to low volumes of BM intake, despite BM Zn concentrations being in the normal range. Promotion of breastfeeding and thereby increasing the volumes of milk produced is a first important step towards improving Zn intake among infants. [ABSTRACT FROM AUTHOR]

Highlights: [•] Silica nanoparticles are functionalized with zinc phthalocyanine complexes. [•] The phthalocyanines are tetra-substituted with amino phenoxy groups. [•] The formed hybrid nanoparticles showed higher triplet quantum yields compared to the free phthalocyanines. [ABSTRACT FROM AUTHOR]

Abstract: Zinc-substituted hydroxyapatite nanoparticles synthesized by the co-precipitation method were used to coat stainless steel plates by electrophoretic deposition in n-butanol with triethanolamine as a dispersant. The effect of zinc concentration in the synthesis on the morphology and microstructure of coatings was investigated. It is found that the deposition current densities significantly increase with the increasing zinc concentration. The zinc-substituted hydroxyapatite coatings were analyzed by X-ray diffraction, scanning electron microscopy and Fourier transform infrared spectroscopy. It is inferred that hydroxyapatite and triethanolamine predominate in the chemical composition of coatings. With the increasing Zn/Ca ratios, the contents of triethanolamine decrease in the final products. The triethanolamine can be burnt out by heat treatment. The tests of adhesive strength have confirmed good adhesion between the coatings and substrates. The formation of new apatite layer on the coatings has been observed after 7days of immersion in a simulated body fluid. In summary, the results show that dense, uniform zinc-substituted hydroxyapatite coatings are obtained by electrophoretic deposition when the Zn/Ca ratio reaches 5%. [Copyright &y& Elsevier]

Highlights: [•] A new pyrazoline-based turn-on fluorescence probe toward Zn2+ was synthesized. [•] Upon addition of Zn2+, the fluorescence intensity was enhanced up to 80-fold. [•] The fast response to Zn2+ makes the probe suitable to monitor Zn2+ in living cell. [ABSTRACT FROM AUTHOR]

A novel composite material, poly(acrylamide-acrylic acid-acrylonitrile)- N, N′-methylenediacrylamide/silicon oxide-zirconium oxide [P(AM-AA-AN)-DAM/SiO-ZrO], was prepared by γ-radiationinduced template copolymerization of acrylic acid (AA) with acrylonitrile (AN) on polyacrylamide P(AM) as a template polymer in presence of N, N′-methylenediacrylamide (DAM) as cross-linker in aqueous solution with water-insoluble mixed oxide of silicon and zirconium. The composite material was characterized by Fourier transform IR spectroscopy and by thermal analysis (synchronized TGA-DTA). The sorption of Cs and Zn(II) onto the prepared composite material was investigated using batch equilibrium technique with variation of pH, adsorbent weight, initial sorbate concentration, contact time, and temperature. The sorption equilibrium data were fitted with the Langmuir and Freundlich isotherm models. The isotherm is successfully fitted by the Langmuir equation over the entire concentration range studied. Lagergren pseudo-first- and pseudo-secondorder kinetic models were tested to describe the reaction mechanism. The experimental data are fitted well the pseudo-second-order model. The thermodynamic functions (free energy Δ G, enthalpy Δ H, entropy Δ S) of the sorption were calculated. These quantities show that the sorption of Cs and Zn onto the composite material is spontaneous and endothermic. [ABSTRACT FROM AUTHOR]

Highlights: [•] Simultaneous determination of cadmium, zinc and cobalt. [•] A novel use of wavelength selection method in UV–Vis spectroscopy. [•] More accurate prediction results obtained in comparison with full spectral calibration. [ABSTRACT FROM AUTHOR]

Acquired adult-onset zinc deficiency is occasionally reported in patients with malnutrition states, such as alcoholism, or malabsorptive states, such as post-bariatric surgery. The defining symptoms of hypozincemia include a classic triad of necrolytic dermatitis, diffuse alopecia, and diarrhea. We report a case of zinc deficiency in a 39-year-old man with history of gastric bypass surgery and alcoholism. For this patient, severe hypozincemia confirmed acrodermatitis, and zinc supplementation was met with gradual improvement. [ABSTRACT FROM AUTHOR]

Highlights: [•] Chemosensor showed very high selectivity to Zn2+ through fluorescence. [•] The stoichiometric ratio evaluated using both Benesi – Hildebrand relation and Job’s plot gives 1:1 stoichiometry. [•] Chemosensor was able to distinguish Zn2+ from Cd2+ commonly having similar properties. [•] Chemosensor exhibits very good fluorescence sensing ability to Zn2+ over a wide range of pH. [ABSTRACT FROM AUTHOR]

Highlights: [•] Zinc was extracted from flour sample using homogenous liquid–liquid microextraction. [•] HLLME is a green extraction technique. [•] This extraction method is simple, efficient and fast. [•] PSO–ANN model was investigated to predict the extraction yield. [•] Determination of the zinc in flour samples was successfully performed. [ABSTRACT FROM AUTHOR]

Five new zinc derivatives of primary amines [R'ZnN(H)R]2 [R = SiPh3, R' = Me (1), N(SiMe3)2 (4); R = Si(NMe2)3, R' = Me (2), Et (3), N(SiMe3)2 (5)] have been synthesised by reaction of R'2Zn and H2NR. All five species are dimers in which the N-H groups are disposed in a trans manner about a central Zn2N2 ring. In 1 and 4 the coordination at zinc is trigonal planar, while in 2, 3, 5 the zinc is in a distorted tetrahedral environment due to additional Me2N: → Zn coordination from one SiNMe2 group. 5 was found to be generally resistant to NH deprotonation by bases such as MN(SiMe3)2 (M = Li, K) or Zn[N(SiMe3)2]2, but reacts with Sn[N(SiMe3)2]2 to give the tin-free, tetrameric mixed zinc-imido/amido species, [{(Me3Si)2N}- {(Me2N)3SiN(H)}{(Me2N)3SiN}Zn2]2 (6) which can be viewed as part of a hexameric Zn6N6 drum which has lost a Zn2N2 ring. [ABSTRACT FROM AUTHOR]

Organozincates or Grignard reagents in the presence of zinc catalysts undergo Michael initiated ring closure (MIRC) reactions with γ,δ-epoxy-α,β-enoates, enones, enesulfones, and enamides to afford 1,2,3-trisubstituted cyclopropanes. The direction of diastereoselectivity is solvent dependent for alkyl Grignard reagents reacting with epoxy enoates, ensulfones, and enamides but solvent independent for the enones. Excellent diastereoselectivity can be achieved for the epoxy enoates, enones, and ensulfones, while the enamides afford modest diastereoselectivity under optimal conditions. The MIRC reaction can be achieved with phenylmagnesium chloride and these substrates under reaction conditions designed to minimize biphenyl formation. [ABSTRACT FROM AUTHOR]

Abstract: Ethno-pharmacological relevance: Soil pollution due to increasing industrialization is a reality that is taking its toll on mankind today. Considering the population of people that use herbal remedies especially in developing countries and the discharge of industrial waste on surrounding herbal vegetation, it is imperative to determine the heavy metals contamination in some commonly used medicinal plants. Materials and methods: Representative samples of five medicinal plants Ageratum conyzoides, Aspilia africana, Alchornea cordifolia, Amaranthus brasiliensis and Chromolaena odorata were collected from Ikpoba-Okha L.G.A, Edo State Nigeria, around a paint company and another set of same plants were collected from a non-polluted source. Dried leaves and roots of collected plants were digested and analyzed using Atomic Absorption Spectrophotometer (AAS) for the presence of Lead (Pb), Cadmium (Cd), Chromium (Cr), Nickel (Ni) and Zinc (Zn). Soil samples from polluted and non-polluted areas were also analyzed to ascertain the levels of these heavy metals in the environment. Results: Results show that the concentrations of these heavy metals in the leaves and roots of plants collected from polluted soil were significantly higher than those obtained from unpolluted soil. Correspondingly heavy metal concentrations were significantly higher in polluted than in unpolluted soil samples. Conclusion: As part of continuing effort in the standardization of traditional remedies, environmental contamination control and abatement is evident. The source of medicinal plants/herbs should also be a cause for concern since the toxicity of medicinal plants is sometimes associated with environmental sources of the plants. [Copyright &y& Elsevier]