Cadmium Salts Research Articles

Influence of heavy metals on hematologic parameters, body weight gain and organ weight in rats

The aim of the study was to determine the effect of Cadmium and Lead salts on body weight gain and rat body weights and hematological parameters. The experiments were conducted in male rats of the Wistar line, weighing 200–220 g, of which four groups of animals were formed: 1) A control group – they injected drinking water through a metal probe in a volume equivalent to the volume of an aqueous solution of Cd2+ salts and Pb2+; 2) Experimental group 1 – animals were administered a 0.029% aqueous solution of cadmium chloride at a dose of 4.0 mg kg-1; 3) Experimental group 2 – animals were administered 16.6% aqueous lead acetate solution at a dose of 200 mg kg-1; 4) Experimental group 3 – animals were administered 16.6% aqueous lead acetate solution at a dose of 100 mg kg-1 and 0.029% aqueous cadmium chloride solution at a dose of 2.0 mg kg-1. Throughout the experiment, rats were kept in a balanced diet containing all the necessary components, and animals were given drinking water, without restriction, from 0.2 liter glass bowls. On the basis of the conducted researches it is established that at loading of an organism of rats by cadmium and Lead salts in rats the weight gain in comparison with intact animals decreased. Reduction of live weight gain in rats by heavy metal intoxication was accompanied by hypo- and hypertrophy of the internal organs. These changes are related to the cumulative and sorption capacity of these metal ions, which contribute to the development of endogenous intoxication of rats in the experimental groups. Chronic lead-cadmium toxicosis in rats was accompanied by erythrocytopenia and leukopenia, as well as a decrease in hemoglobin with a simultaneous increase in erythrocyte volume and average erythrocyte hemoglobin content.

Community recovery dynamics in yellow perch microbiome after gradual and constant metallic perturbations

BackgroundThe eco-evolutionary processes ruling post-disturbance microbial assembly remain poorly studied, particularly in host-microbiome systems. The community recovery depends not only on the type, duration, intensity, and gradient of disturbance, but also on the initial community structure, phylogenetic composition, legacy, and habitat (soil, water, host). In this study, yellow perch (Perca flavescens) juveniles were exposed over 90 days to constant and gradual sublethal doses of cadmium chloride. Afterward, the exposure of aquaria tank system to cadmium was ceased for 60 days. The skin, gut and water tank microbiomes in control and treatment groups, were characterized before, during and after the cadmium exposure using 16s rDNA libraries and high throughput sequencing technology (Illumina, Miseq).ResultsOur data exhibited long-term bioaccumulation of cadmium salts in the liver even after two months since ceasing the exposure. The gradient of cadmium disturbance had differential effects on the perch microbiota recovery, including increases in evenness, taxonomic composition shifts, as well as functional and phylogenetic divergence. The perch microbiome reached an alternative stable state in the skin and nearly complete recovery trajectories in the gut communities. The recovery of skin communities showed a significant proliferation of opportunistic fish pathogens (i.e., Flavobacterium). Our findings provide evidence that neutral processes were a much more significant contributor to microbial community turnover in control treatments than in those treated with cadmium, suggesting the role of selective processes in driving community recovery.ConclusionsThe short-term metallic disturbance of fish development has important long-term implications for host health. The recovery of microbial communities after metallic exposure depends on the magnitude of exposure (constant, gradual), and the nature of the ecological niche (water, skin, and gut). The skin and gut microbiota of fish exposed to constant concentrations of cadmium (CC) were closer to the control negative than those exposed to the gradual concentrations (CV). Overall, our results show that the microbial assembly during the community recovery were both orchestrated by neutral and deterministic processes.8KR8qv6CEcKmimx9at5UakVideo Abtract.

The effect of nitrogen monoxide donors on the indexes of cadmium-induced oxidative stress in different rat tissues

Oxidative stress is considered to be the main mechanism of cadmium ions toxic effect on the cells and is caused by cadmium, as a non-transition metal, indirectly. Oxidative damage to cells due to the action of cadmium ions is tissue-specific and is associated with the antioxidant system inhibition, free heme accumulation and essential metals substitution in metalloproteins. Nitrogen monoxide (NO) exhibits high affinity for heme and proteins and peptides sulfhydryl groups, known to be the main molecular targets for cadmium ions. Taking all the above-mentioned into account, the aim of this work was to study the effect of NO radicals donors on the prooxidant-antioxidant state of mammalian tissues under oxidative stress caused by cadmium chloride administration in vivo. Male Wistar rats weighing 160–200 g were used in the study. CdCl2 was administered subcutaneously at a dose of 14 mg/kg body weight. The direct donor of the NO radical sodium nitroprusside (SNP, 1 mg/kg mass) and the substrate of the NO synthase reaction L-arginine (600 mg/kg mass) were administered intraperitoneally. In order to study the corrective action, donors of the NO radical were injected 0.5 h before the cadmium salt. The objects of investigation were blood plasma and liver, kidneys and spleen homogenates of rats. The cadmium chloride treatment caused a number of prooxidant-antioxidant balance disorders, most of which were revealed a day after injection. The accumulation of lipid peroxidation products was found in rat serum, liver, and spleen. The enhancement of prooxidant processes in these tissues may originate from cadmium ions and hemolysis products entry. In the antioxidant system, significant changes were observed under cadmium action only in the liver: an increase in the reduced glutathione content and SOD activity and a decrease in catalase activity. The precursor of nitric oxide L-arginine did not change the basal level of prooxidant-antioxidant parameters, and in most cases did not affect their dynamics in the organs studied after cadmium chloride administration. A direct NO donor, sodium nitroprusside, acted in liver and spleen mostly as a prooxidant. In liver, the injection of only nitroprusside, as well as the combined administration of SNP and CdCl2, led to free radical processes activation just in two hours. In spleen, the combined treatment by SNP and cadmium salt also caused an earlier development of oxidative stress, as witnessed by an increase in lipid hydroperoxides level and a decrease in reduced glutathione content. Therefore, the injection of a direct NO donor, sodium nitroprusside, and a substrate of NO synthase, L-arginine, in selected doses has insignificant corrective action on cadmium-induced oxidative stress in the liver, kidneys and spleen. However, in blood both donors of NO effectively prevented the accumulation of lipid peroxidation products under CdCl2 treatment; in addition, L-arginine significantly reduced the lactate dehydrogenase release, which may indicate blood cells and blood vessels protection from the damage caused by cadmium ions.

Bioprotective properties of nano-diamond composition at intragastric introduction to rats

We studied a biocompatibility and a bioprotector property of nanodiamond composites on reduction of the toxic action to cadmium salt. The experimental animal intragastric received with the help of a probe activated carbon and nanodiamond composite. We researched the rate of spontaneous and ascorbate-dependent lipids peroxidation and the reference level of malonic dialdehyde in liver, thyroid and adrenal glands tissues. So this concentration of the nanopore material at intragastric entering did not led to difference of researched parameters of the lipid peroxidation. The solution of cadmium salt developed typical for it toxic action which expressed in increase intensity of the processes of POL in liver and thyroid gland tissues. The nanopore material developed the characteristic which screened the toxic action of cadmium chloride and it was more denominated on some parameters in comparison with the effect of the intragastric entering of the activated carbon.

Changes in rat myocardium contractility under subchronic intoxication with lead and cadmium salts administered alone or in combination

Subchronic intoxications induced in male rats by repeated intraperitoneal injections of lead acetate and cadmium chloride, administered either alone or in combination, are shown to affect the biochemical, cytological and morphometric parameters of blood, liver, heart and kidneys. The single twitch parameters of myocardial trabecular and papillary muscle preparations were measured in the isometric regime to identify changes in the heterometric (length-force) and chronoinotropic (frequency-force) contractility regulation systems. Differences in the responses of these systems in trabecules and papillary muscles to the above intoxications are shown. A number of myocardium mechanical characteristics changing in rats under the effect of a combined lead-cadmium intoxication and increased proportion of α-myosin heavy chains were observed to normalize fully or partially if such intoxication was induced against background administration of a proposed bioprotective complex. Based on the experimental results and literature data, some assumptions are suggested concerning the mechanisms of the cardiotoxic effects produced by lead and cadmium.

Determination of Nitrogen Dioxide by Thin-Film Chemical Sensors Based on CdxPb1 –xS

The results of a study of sensors based on thin semiconductor films of CdxPb1 – xS solid solutions intended for the determination of nitrogen dioxide in air are described. For a comparative assessment of the composition, morphology, and functional properties of the films, they were synthesized from reaction mixtures containing various cadmium salts. It was found that the maximum response is provided by layers obtained using cadmium acetate, in which the composition of the solid solution differs in the maximum supersaturation level in CdS. The films were formed of crystallites with average sizes of ~200 nm. When the concentration of nitrogen dioxide in air was 0.05‒200 mg/m3, the relative change in the ohmic resistance of sensors ranged from 8 to 80%. It was shown that the threshold concentration of NO2 in air was about 0.02 mg/m3. The reversible nature of the gas adsorption process opens a possibility for the creation of reusable chemical sensors based on CdxPb1 – xS films, differing in a relatively low threshold concentration of NO2 detection and selective response in the presence of significantly higher concentrations of O2, CO2, and H2.

Neutron Imaging of Cadmium Sorption and Transport in Porous Rocks

Understanding fluid flow in rocks is crucial to quantify many natural processes such as ground water flow and naturally triggered seismicity, as well as engineering questions such as displacement of contaminants, the eligibility of subsurface waste storage, geothermal energy usage, oil and gas recovery and artificially induced seismicity. Two key parameters that control the variability of fluid flow and the movement of dissolved chemical species are (i) the local hydraulic conductivity, and (ii) the local sorption properties of the dissolved chemical species by the solid matrix. These parameters can be constrained through tomography imaging of rock samples subjected to fluid injection under constrained flow rate and pressure. The neutron imaging technique is ideal to explore fluid localization in porous materials due to the high but variable sensitivity of neutrons to the different hydrogen isotopes. However, until recently, this technique was underused in geology because of its large acquisition time. With the improved acquisition times of newly set-up neutron beamlines, it has become easier to study fluid flow. In the current set of experiments, we demonstrate the feasibility of in-situ 2D and 3D time-lapse neutron imaging of fluid and pollutant percolation in rocks, in particular that of cadmium salt. Cadmium is a hazardous compound that is found in many electronic devices, including batteries and is a common contaminant in soil and groundwater. It also exhibits higher contrast in neutron attenuation with respect to heavy water, and is therefore an ideal tracer. Time-lapse 2D radiographies and 3D neutron tomographies of the samples were acquired on two neutron beamlines (ILL, France and SINQ, Switzerland). We performed two sets of experiments, imbibition and injection experiments, where we imaged in-situ flow properties, such as local permeability and interactions between cadmium and the solid rock matrix. Our results indicate that even within these cm-scale porous rocks, cadmium transport follows preferential pathways, and locally interacts within the limestone samples. Our results demonstrate that the use of neutron imaging provides additional insights on subsurface transport of pollutants.

Siderophore-assisted cadmium hyperaccumulation in Bacillus subtilis.

Siderophores (Gk iron carriers) are low molecular weight secondary metabolites produced by bacteria, fungi, and plants that have strong binding affinity for iron. Owing to their iron-chelating ability, they are produced mainly when the organism faces iron scarcity. The present study empirically investigated the importance of applying hydroxamate siderophore extracted from Aspergillus nidulans to the cells of Bacillus subtilis for bioremediation of cadmium salt. This investigation deals with siderophore-mediated intracellular Cd accumulation by bacterial cells, growth estimation, biochemical assays like lipid peroxidation, total protein content, carbohydrate content, and iron content estimation. In silico docking and STRING analyses revealed specific interaction between Aspergillus siderophore and receptors present on B. subtilis. Estimation of intracellular Cd by atomic absorption spectroscopy showed more accumulation of Cd ions by B. subtilis in the presence of hydroxamate siderophore. This suggests a possibility of confiscating environmental Cd2+ by utilizing metal chelation property of siderophores and hence can lead to emerging bioremediation mechanisms for heavy metals. In silico studies support experimental investigation and suggest higher affinity of siderophore for Cd ions as compared with ferric ions.

Response of transgenic tobacco overexpressing the CchGLP gene to cadmium and aluminium: phenotypic and microRNAs expression changes.

Transgenic tobacco (N. tabacum cv. Xanthi nc) expressing Capsicum chinenseCchGLP gene that encodes an Mn-SOD, constitutively produces hydrogen peroxide that increase endogenous ROS levels. Previous studies using these plants against geminivirus infections as well as drought stress confirmed that CchGLP expression conferred resistance against biotic and abiotic stresses. Cadmium (Cd) and Aluminium (Al) contamination in soils are a major ecological concern since they are two of themost widespread toxic elements in terrestrial environments. Trying to explore additional possible tolerance to another stresses in these plants, the aim of this work was to analyse the response to cadmium and aluminium salts during germination and early stages of plantlet development and a differential transcriptome of microRNAs (miRNAs) expression in expressing CchGLP transgenic lines and an azygote non-CchGLP expressing line. Plants were grown in vitro with addition of CdCl2 and AlCl3 at three different concentrations: 100, 300 and 500μM and 50, 150 and 300μM, respectively. The results showed higher tolerance to Cd and Al salts evaluated in two CchGLP-expressing transgenic lines L8 and L26 in comparison with the azygous non-CchGLP expressing line L1. Interestingly, L8 under Al stress presented vigorous roots and development of radicular hairs in comparison with azygous control (L1). Differentially expressed miRNAs in the comparison between L8 and L1 were associated with up and down-regulation of target genes related with structural molecule activity and ribosome constituents, as well as down-regulation in proton-transporting V-type ATPase (Vacuolar ATPase or V-ATPase). Moreover, KEGG analysis of the target genes for the differentially expressed miRNAs, led toidentification of genes related with metabolic pathways and biosynthesis of secondary metabolites. One possible explanation of the tolerance to Cd and Al displayed in the transgenic tobaccos evaluated, might involve the fact that several down-regulated miRNAs, were found associated with target genes expressing V-ATPase. Specifically, miR7904-5p was down regulated and related with the up-regulation of one V-ATPase. The expression levels of these genes was confirmed by qRT-PCR assays, thus suggesting that a cation transport activity driven by the V-ATPases-dependent proton motive force, might significantly contribute as one mechanism for Cd and Al detoxification by vacuolar compartmentation in these transgenic tobacco plants.

Nano-synthesis, spectroscopic characterization, quantum chemical calculations, thermal properties and antimicrobial activity of (E)-N′-(2-hydroxybenzylidene)morpholine-4-carbothiohydrazide ligand and its metal complexes

The (E)-N′-(2-hydroxybenzylidene)morpholine-4-carbothiohydrazide (H2L) ligand and its chelates with Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) have been synthesized. Analytical and spectral data prove that the ligand acts a monobasic tridentate ligand coordinated via deprotonated phenolic O, azomethine N and thione S atoms (ONS chromophore) with cobalt(II), nickel(II) and copper(II) salts leading to two fused five and six-membered chelate rings. While with zinc(II) and cadmium(II) salts the ligand behaves as a neutral bidentate and coordinated through the azomethine nitrogen and thione sulfur (NS type). The percent of weight losses during thermal degradation processes are in agreement with the proposed formulae as indicated by the TG/DTG studies. The X-ray diffraction patterns (XRD) indicate nano-sized particles and crystalline nature of the free organic ligand as well as all of its metal complexes. The corresponding predicted spectral data of H2L and its metal chelates were calculated in the Polarizable Continuum Model (PCM) using DFT and DT-DFT methods at the B3LYP/LanL2DZ level of theory. The obtained results showed a relatively good agreement between the experimental and predicted spectral data. The in vitro antibacterial and antifungal properties of the H2L and its metal complexes against four bacteria, Gram-positive (Staphylococcus aureus and bacillus subtilis) and gram-negative (Escherichia coli and proteus vulgaris) and two strains of fungus (Aspergillus fumigatus and candida albicans) showed that metal chelates exhibit more inhibitory effects than the free ligand. Selectivity is detected in the activities of some compounds over certain microorganisms, which is important for future pharmaceutical applications.

Pulse Electroplating of Zinc/Nickel Alloy from a Deep Eutectic Solvent (DES)

Electrodeposition of metal coatings such as nickel, zinc, tin, chromium and cadmium for the purposes of corrosion protection has been a core interest of the electrochemical community for more than one hundred years. Cadmium has been a favourite for military and aerospace applications because of the combination of good corrosion protection and lubricity. However, cadmium salts are very toxic and hazardous and so the use of cadmium coatings is now proscribed in all but the most demanding of applications. Alternatives to cadmium coatings have included aluminium and more recently zinc nickel alloys. The latter is more accessible via aqueous methods but requires rigorous control and monitoring of bath conditions in order to maintain the composition and quality of the coating. An alternative to aqueous electrolytes is a derivative of ionic liquids that feature eutectic mixtures of quaternary ammonium salt and hydrogen bond donor. These have become known as deep eutectic solvents (DSE). Here we have used a DES to produce coherent and adherent coatings of zinc nickel alloy in an electrochemical study and in pre-commercialisation scale-up trials. In a digital controlled pulse-plating method, alternative forward (deposition) and reverse (stripping) currents, are applied to adjust the deposit composition and morphology, as has been demonstrated in film plating from aqueous electrolytes. This report focuses on pulse-plating γ-Zn11Ni2 alloy from a eutectic mixture of choline chloride (ChCl) and ethylene glycol (EG), also known by the commercial name of Ethaline. The effect of pulse shape and frequency on deposit morphology and crystal structure were analysed and compared with coatings derived from constant current (DC) plating methods, through Hull cell tests, XRD, and SEM/EDX measurement. The deposit composition is shown here to be dependent on the average current density, the surface morphology is not sensitive to the pulse frequency, while dendritic growth is shown to be suppressed by pulsed current. We show that the crystal grain size can be controlled according to the pulse shape and frequency. By choosing a certain shape and frequency, the pulse-plating in the DES can provide improved coating qualities and improved process control. Additionally, we have extended the laboratory investigation to pre-commercial scale-up trials with a commercial electroplating company (EC Williams, UK). This project is funded by an Innovate UK action and is entitled Cadmium Replacement Using Pulse-Plating and Ionic Liquids (CRUPPAIL). Barrel-plating trials using pulse and reveres pulse methods on small components such as screws have given even adherent coatings, Figure. The combination of pulse methods and DES electrolyte give a levelling effect, Figure (a), and good throwing power in confined geometries, Figure (b). Figure: Scanning electron micrographs of Zinc Nickel alloy (85:15%) deposited using DES and pulse-plating on mild steel substrates, (a) sheet, (b) screws. Figure 1

Effectiveness of 2-Hydroxybenzoic Acid in Physiologic Response of Basket Willow (Salix viminalis L.) on Stress Induced by Cadmium

The aim of the study was an evaluation of the effect of exogenous application of 2-hydroxybenzoic acid on the performance of photosynthetic apparatus of two basket willow (Salix viminalis L.) varieties growing in elevated concentrations of cadmium salts and an evaluation of the suitability of fluorescence method to characterize the physiological state of the examined willow genotypes under stress conditions caused by an increased content of cadmium ions. The influence of cadmium ions at a concentration of 50 mg/dm3 and salicylic acid at a concentration of 138 mg/dm3 on the physiological reaction of basket willow of Bjor and Tora varieties cultivated in hydroponics was investigated. The applied dose of salicylic acid effectively eliminated the influence of cadmium, activating the synthesis of chlorophyll a and b and carotenoids as well as increasing the intensity of the determined fluorescence processes and indicators. The use of the fluorescent method to characterize the physiological state of the examined willow genotypes under the conditions of stress caused by an increased content of cadmium ions allows a better understanding of the immune system’s response to these metal ions.

Anion-controlled structural motifs in cadmium coordination polymers: Formation of linear chain versus triple-stranded ladder

Three novel coordination polymers [CdL(NCS)2(DMSO)2]n (1), {[Cd3L3(OAc)4(NCS)2] (DMSO)2]}n (2) and [CdL(µ-SeCN)2]n (3) have been synthesized by using exoditopic N-donor Schiff base ligand 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene (L) in the presence of different cadmium salts. The results show that anion has an important role in the formation of different structural motif. X-ray structural analysis shows that in these cases 1D linear chain, 1D triple-stranded ladder and 2D structural motifs have been formed for compound 1, 2 and 3, respectively. Our results showed that solvent type affect morphology of compound 1.

Synthesis and Structural Investigation of Some Transition Metal Complexes Derived from Assembled NO Donor Lewis Base of 6,7-Dimethyl-Quinoxaline-2,3-dione

The synthesis of a new ligand (Z)-3-((2-aminoethyl)imino)-6,7-dimethyl-3,4-dihydroquinoxalin-2(1H)-one containing quinoxaline and aliphatic ethylene moiety subunits is described. The reaction of 6,7-dimethylquinoxaline-2,3(1H,4H)-dione with ethylenediamine in glacial acetic acid as catalyst leads to the isolation of the free ligand (L), which is a Lewis base precursor. The new transition metal complexes of (L) ligand were prepared and characterized by elemental analysis and spectroanalytical techniques. The new poly dentate L Schiff base was formed up on condensation of 6,7-dimethylquinoxaline-2,3(1H,4H)-dione with ethylenediamine in glacial acetic acid as catalyst. The free ligand was fully identified with the help of elemental analyses, mass spectra,H NMR and FTIR spectra. The direct reactions of methanolic ligand (L) with the salts of manganese(II),cobalt(II),nickel(II),copper(II),zinc(II),cadmium(II) and vanadium(IV) resulted in colored precipitated which have been characterized by elemental analyses, magnetic susceptibility, molar conductivity measurements and FTIR and UV-Visible spectroscopy. The metal to ligand ratios data concluded that all structures of complexes were in 1:1 ratio with octahedral geometry for all complexes except that nickel(II) was square planner The compounds were characterized by physical and spectroscopic measurements which indicated that the ligand is probably acting as a tridentate ON2 chelating agent.

Adsorption and sequestration of cadmium ions by polyptychial mesoporous biochar derived from Bacillus sp. biomass.

Bacteria-derived biochars from Bucillus sp. biomass under different pyrolysis temperature (250°C, 350°C, 450°C, and 550°C, respectively) were prepared, forming polyptychial, mesoporous graphite-like structure. The adsorption and sequestration efficiencies of Cd2+ by these biochars were evaluated, and the underlying mechanisms were then discussed. Cd2+ sorption data could be well described by Langmuir mode while the pseudo-second-order kinetic model and Elovich model best fitted the kinetic data. The functional groups complexation, cation-π interactions, and interaction with minerals (including surface precipitation with phosphorus and ion exchange) jointly contributed to Cd2+ sorption and sequestration on biochar, but the interaction with minerals played a dominant role by forming insoluble cadmium salt composed by polycrystalline and/or amorphous phosphate-bridged ternary complex. The maximum sorption capacity of BBC350 in simulated water phase of soil for Cd2+ was 34.6mg/g. Furthermore, the addition of bacteria-derived biochars (1%, w/w) decreased the fractions easily absorbed by plants for Cd in the test paddy soils by 1.9-26% in a 10-day time. Results of this study suggest that bacteria-derived biochar would be a promising functional material in environmental and agricultural application.

Модифікуючий вплив цитрату селену та цитрату германію на ембріотоксичність солей кадмію при комбінованому введенні у щурів

Модифікуючий вплив цитрату селену та цитрату германію на ембріотоксичність солей кадмію при комбінованому введенні у щурів

Prospects of Stenotrophomonas pavanii DB1 in diesel utilization and reduction of its phytotoxicity on Vigna radiata

Diesel, for its carcinogenic and teratogenic properties, is considered as an environmental hazard. The present study concentrates on diesel utilization by Stenotrophomonas pavanii DB1 under various physicochemical parameters and mass spectral analysis of the metabolites produced. Soil remediation potential of the culture for reducing diesel toxicity against Vigna radiata seed germination was also evaluated. Supplementation of the broth with ammonium sulfate, molasses and tween 80 enhanced diesel utilization (up to 66.3%). A steady decrease in diesel utilization (69.46–51.23%) was recorded with the increase in salinity from 1 to 5000 mM. Similarly, the utilization efficiency was low (up to 11.5%) when cadmium, lead and mercury salts were present but was not affected by zinc and copper salts. Liquid chromatography–mass spectrometry revealed extensive utilization (95–99%) of both the short- (C10–C20) and long-chain (C18–C30) n-alkanes. Significantly, the culture exhibited uniform utilization of various recalcitrant n-alkanes, to generate metabolites like aldehyde, ketone, fatty acids, carboxylic and dicarboxylic acids. Stenotrophomonas pavanii DB1 mediated 95% and 86% of diesel utilization in soil with and without nutrient amendment, respectively. Germination percentage of V. radiata seeds improved with the bacterial inoculation of the diesel-containing soil. Stenotrophomonas pavanii DB1 culture did not establish antagonistic effect over the resident soil bacteria. Based on the spectral analysis and soil remediation studies, it could be inferred that S. pavanii DB1 is a potential culture for bioremediation of sites polluted with diesel.

Synthesis, Thermal Characterization and in vitro Antibacterial Assessment of Co(II) and Cd(II) Complexes of Schiff Base Derived from Amoxicillin and Thiophene-2-carbaldehyde

A novel AMXTC2 ligand was prepared by simultaneous stirring and refluxing of an equimolar mixture of amoxicillin and thiophene-2-carbaldehyde in methanol and was further used to synthesize metal complexes by metalation with cobalt and cadmium salts, taking ligand metal ratio 2:1. They were characterized by elemental microanalysis, FT-IR, mass, UV-visible, 1H NMR, thermal analysis, magnetic moment and molar conductance measurements. The coordination sites in the ligand were verified by their comparative and extensive spectral studies. The detailed exploration of the data suggested octahedral geometry for Co-AMXTC2 and tetrahedral geometry for Cd-AMXTC2 complexes. The thermodynamic and kinetic parameters such as E*, ΔH*, ΔS* and ΔG* of various decomposition steps were calculated from TGA curves using the Coats-Redfern method. The molar conductivity data suggested non-electrolytic nature of the complexes. SEM analysis was done to observe their surface morphology. The geometry optimization of the proposed molecular structure of the complexes was achieved by running MM2 calculation in Gaussian supported Cs-ChemOffice Ultra-11 program software. The biological activities had been evaluated in vitro against E. coli, K. pneumonia, P. vulgaris and S. aureus pathogens in order to assess their antibacterial potency. The biological data revealed better growth inhibitory action of the ligand and metal complexes with bacterial pathogens.

In vitro cyto-toxic assessment of heavy metals and their binary mixtures on mast cell-like, rat basophilic leukemia (RBL-2H3) cells

We investigated the cytotoxicity and mechanisms of cell death induced by salts of Cadmium (Cd2+), Lead (Pb2+), Arsenic (AsO43−) and Chromium (Cr+6) on RBL-2H3 cells (a model mast cell line). In addition, cyto-toxic effect on cell viability was assessed to reveal their nature of interaction in binary mixture. The individual cytotoxic characteristics of these metals on RBL-2H3 cell viability showed a concentration-dependent reduction of cell viability. We observed that concentration-dependent cytotoxic potency on RBL-2H3 cells of these metals range in the following order Cd2+>Cr+6>As O43− > Pb2+ with LC50 values of 0.11 μM, 93.58 μM, 397.9 μM and 485.3 μM respectively. Additive effects were observed with Pb2+ + Cd2+, Pb2+ + AsO43−, Pb2+ + Cr+6 and AsO43− + Cr+6. The study revealed that Pb2+, Cd2+, AsO43− and Cr+6 could induce significant (P < 0.01) cell death by apoptosis in RBL-2H3. Highly significant necrotic cell death was observed with Pb2+ and Cr+6 (P < 0.01) than Cd2+ and AsO43− (P < 0.05). Overall, it can be deduced that several cell death executing pathways may be concomitantly activated on exposure to heavy metals and the predominance of one over others might depend on the type of heavy metal, concentration and the metabolic state of the cell. Eventually, binary mixtures of some of these metals showed less cytotoxicity than would be expected from their individual actions and may depend on the co-exposure of the metal ions and their modes of action.

Synthesis of cadmium sulphide nanoparticles through liquid membrane pathway

This paper introduces a proof of concept that liquid membrane technology that has always been used as a separation technique, can also be extended for the generation of value added products in its downstream side. It is possible to generate cadmium sulphide nanoparticles in the stripping phase of liquid membrane separation unit which have wide industrial application such as solar and photovoltaic cells. The process parameters such as concentration of cadmium salt and pH in feed phase, concentration of strippant, concentration of extractant/carrier agent, etc. were optimised leading to maximum production of CdS nanoparicles in the stripping phase. The characterisation of CdS nanoparticles were carried out using TEM, FESEM-EDX, FT-IR, XRD and SAED. The nanosize and nanocrystalline nature of the CdS particles were established.