Scientific Literature

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Production and catalytic upgrading of 2,3-butanediol fermentation broth into sustainable aviation fuel blendstock and fuel properties measurement

Date: 2023
Authors: Affandy, M;Zhu, C;Swita, M;Hofstad, B;Cronin, D;Elander, R;Lebarbier Dagle, V;
References: Fuel 333 126328
Keywords/Products: Meinhard;POINT;
With the increasing demand for sustainable supplies of aviation fuel and need to address climate change, new conversion technologies are needed to efficiently process biomass, produce high quality jet fuel blendstock, and meet carbon emission targets. This study demonstrates the synthesis, conditioning, and catalytic upgrading of 2,3-butanediol (BDO) fermentation broth into a jet fuel blendstock candidate. A high-titer 2,3-BDO fermentation broth (i.e., ?90 g/L) was produced at a 100-L scale and pretreated via nanofiltration to decrease the impurities level in the broth from 4.6 to 0.6 wt%. A novel process for catalytic upgrading of aqueous 2,3-BDO into a jet fuel blendstock candidate was developed, and each step was efficiently demonstrated. The catalytic steps include 1) 2,3-BDO dehydration into methyl ethyl ketone (MEK) over AlPO4, 2) MEK conversion into olefins over Zn1Zr10Ox, 3) oligomerization of olefins over a zeolite beta, and 4) hydrogenation over platinum/carbon. Both the model feed and real 2,3-BDO fermentation broth were tested for upgrading 2,3-BDO to MEK. With the real feed, a continuous loss of conversion (i.e., >50 % loss over ?140 h time-on-stream [TOS]) was partly attributed to reversible deactivation from coking species. However, the conversion remained stable with the model feed, which demonstrates the efficiency of the first step for converting aqueous 2,3-BDO (10 wt% in water). For upgrading MEK to olefins, high selectivity to olefins (i.e., 82.5 %) was obtained at high conversion levels (i.e., 93-98 %) with stable conditions being achieved for > 70-hours TOS. Oligomerization of light olefins, which was demonstrated for > 270 h TOS, mainly led to the formation of dimers (C8-10) and trimers (C13-14). The oligomerized product was hydrogenated and distilled to recover the jet fraction (35 mass% or 40.9 % carbon based yield), which consists mostly of desired isoalkanes (31.7 wt%), n-alkanes (24.5 wt%), and cycloalkanes (29.6 wt%). While some improvement is still needed to meet ASTM D7566 specifications for viscosity and final boiling point temperature, freezing point, density, aromatics content, and sulfur content of the jet blendstock candidate were within acceptable ranges, thus highlighting the potential of this process for production of jet fuel blendstock.

Arsenic speciation in canned tuna fish samples (Thunnus) using ionic chromatography inductively coupled plasma mass spectrometry

Date: 2023
Authors: Hoyne, T;Vieira, L;Heringer, O;Brandão, G;Souza, J;Carneiro, M;
References: Journal of Food Composition and Analysis 116 105051
Keywords/Products: Concentric;Concentric nebulizer;ICP;ICP-MS;Meinhard;
Arsenic speciation analysis was conducted on in oil and in brine canned solid tuna samples using ionic chromatography inductively coupled plasma mass spectrometry (IC-ICP-MS). First, the method was optimized and validated. The extraction of water-soluble arsenic species (arsenobetaine (AsB), dimethylarsinic acid (DMA), monomethylarsonic acid (MMA), As (III), and As (V)) was performed with (NH4)2CO3 at pH 10.5. The presence of the sample matrix showed no effect on the selectivity of the method by a t-test (p < 0.05) and an external calibration method was applied. The limits of quantification for the five arsenic species were 0.59 mg kg?1 (AsB), 0.10 mg kg?1 (DMA), 0.12 mg kg?1 (As (III)), 0.07 mg kg?1 (MMA) and 0.10 mg kg?1 (As (V)). Method accuracy was tested through the analysis of the reference material BCR-627 (tuna fish muscle tissue) and a good agreement was obtained. Total arsenic in the solid canned tuna ranged from 2.65 to 5.81 mg kg?1 in-oil samples and from 2.74 to 5.70 mg kg?1 in the in-brine samples, levels higher than the limits established by the Brazilian sanitary standards. However, the speciation showed that the major species is the non-toxic arsenobetaine.

Species- and Metal-Specific Responses of the Ionome of Three Duckweed Species under Chromate and Nickel Treatments

Date: 2023
Authors: Oláh, V;Irfan, M;Szabó, Z;Sajtos, Z;Ragyák, Á;Döncz?, B;Jansen, M;Szabó, S;Mészáros, I;
References: Plants 12 180
Keywords/Products: Agilent;ICP;ICP-OES;Meinhard;
In this study, growth and ionomic responses of three duckweed species were analyzed, namely Lemna minor, Landoltia punctata, and Spirodela polyrhiza, were exposed for short-term periods to hexavalent chromium or nickel under laboratory conditions. It was found that different duckweed species had distinct ionomic patterns that can change considerably due to metal treatments. The results also show that, because of the stress-induced increase in leaf mass-to-area ratio, the studied species showed different order of metal uptake efficiency if plant area was used as unit of reference instead of the traditional dry weight-based approach. Furthermore, this study revealed that ?XRF is applicable in mapping elemental distributions in duckweed fronds. By using this method, we found that within-frond and within-colony compartmentation of metallic ions were strongly metal- and in part species-specific. Analysis of duckweed ionomics is a valuable approach in exploring factors that affect bioaccumulation of trace pollutants by these plants. Apart from remediating industrial effluents, this aspect will gain relevance in food and feed safety when duckweed biomass is produced for nutritional purposes.

Image-Guided Nanodelivery of Pt(IV) Prodrugs to GRP-Receptor Positive Tumors

Date: 2023
Authors: Silva, F;Mendes, C;D'Onofrio, A;Campello, MPC;Marques, F;Pinheiro, T;Gonçalves, K;Figueiredo, S;Gano, L;Ravera, M;Gabano, E;Paulo, A;
References: Nanotheranostics 7 22-40
Keywords/Products: Concentric;Concentric nebulizer;ICP;ICP-MS;Meinhard;PC3;Thermo;
Over the last decades, gold nanoparticles (AuNPs) have proven to be remarkable tools for drug delivery and theranostic applications in cancer treatment. On the other hand, Pt(IV) prodrugs have been employed as an interesting alternative to the more common Pt(II) complexes, such as cisplatin, for cancer chemotherapy. Searching to design an image-guided nanocarrier to deliver selectively Pt(IV) prodrugs to tumors expressing the gastrin releasing peptide receptor (GRPR), we have synthesized small core AuNPs carrying a thiolated DOTA derivative, a GRPR-targeting bombesin analog (BBN[7-14]) and a Pt(IV) prodrug attached to the AuNPs without (AuNP-BBN-Pt1) or with a PEGylated linker (AuNP-BBN-Pt2 and AuNP-BBN-Pt3). In the GRPR+ prostate cancer PC3 cell line, the cytotoxic activity of the designed AuNP-BBN-Pt nanoparticles is strongly influenced by the presence of the PEGylated linker. Thus, AuNP-BBN-Pt1 displayed the lowest IC50 value (9.3 ± 2.3 µM of Pt), which is comparable to that exhibited by cisplatin in the same cell line. In contrast, AuNP-BBN-Pt1 showed an IC50 value of 97 ± 18 µM of Pt in the non-tumoral RWPE-1 prostate cells with a much higher selective index (SI) towards PC3 cells (SI = 10) when compared with cisplatin (SI = 1.3). The AuNPs were also successfully labeled with 67Ga and the resulting 67Ga-AuNP-BBN-Pt were used to assess their cellular uptake in PC3 cells, with AuNP-BBN-Pt1 also displaying the highest cellular internalization. Finally, intratumoral administration of 67Ga-AuNP-BBN-Pt1 in a PC3 tumor-bearing mice showed a prolonged retention of the nanoparticle compared to that of cisplatin, with optimal in vivo stability and 20% of the injected platinum remaining in the tumor after 72 h post-injection. Furthermore, microSPECT imaging studies confirmed the uptake and considerable retention of the 67Ga-labeled AuNPs in the tumors. Overall, these results show the potential of these targeted AuNPs loaded with Pt(IV) prodrugs for prostate cancer theranostics.

Smelter-derived soil contamination in Luanshya, Zambia

Date: 2023
Authors: Baieta, R;Ettler, V;Van?k, A;Drahota, P;K?íbek, B;Nyambe, I;Mihaljevi?, M;
References: The Science of the total environment 867 161405
Keywords/Products: Meinhard;
Extensive mining and smelting contributed to the declining quality of Luanshya soils. The local smelter was the epicenter of contamination as shown by a spatial distribution analysis. Closeby soil profiles smelter exhibit extremely high Cu concentrations (up to 46,000 mg kg-1 Cu) relative to deeper layers where only background levels of trace elements were observed. A remote profile did not exhibit significant contamination. Lead isotopic ratios revealed that Pb contamination in the Luanshya soils was not smelter-derived. It was shown in this way that the historical usage of leaded gasoline was the main source of this metal. Although the Luanshya smelter also produced Co, this metal was not an important contaminant. Copper leaching was a concern in Luanshya. Upwards of 52 % of Cu was extractable in the exchangeable step of a sequential extraction procedure (SEP), but only for samples where Cu concentrations were high, suggesting that Cu was released exclusively from anthropogenic particles. This was supported by the SEP results for similar depths at the remote soil, where only a small fraction of Cu was labile (5.6 %). Lead and Co were strongly bound in the soils throughout. The excess of Cu in the topsoils was mostly bound in smelter-derived particles. These appeared as spherical fast-cooled droplets composed mostly of sulfides, oxides, and glass. X-ray diffraction and electron probe microanalysis of those particles allowed for a phase classification. Compositions were regularly not stoichiometric so most particles were classified as intermediate solid solutions. However, molecular proportions often closely resembled those of bornite, chalcanthite, cuprospinel, covellite, delafossite, diginite, or hydrous ferric oxides. Concentrations of Cu were often 100 % near the center of the particles indicating an inefficient smelting process. Weathering to some degree was common, which in conjunction with the susceptibility of Cu leaching was highly alarming.

Environmental exposure to cadmium in breast cancer - association with the Warburg effect and sensitivity to tamoxifen

Date: 2023
Authors: Tarhonska, K;Janasik, B;Roszak, J;Kowalczyk, K;Lesicka, M;Reszka, E;Wieczorek, E;Braun, M;Kolacinska-Wow, A;Skokowski, J;Kalinowski, L;Jablonska, E;
References: Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie 161 114435
Keywords/Products: ELAN;ICP;ICP-MS;Meinhard;Quartz Nebulizer;
The association between cadmium and breast cancer remains unexplained due to inconsistent epidemiological data and unknown underlying mechanisms. This study aimed to assess the relationship between environmental exposure to cadmium and the Warburg effect in breast cancer and, thus, its possible interference with breast cancer treatment. The observational study in two groups of breast cancer patients indicated a positive correlation between urinary cadmium concentration and tumor expression of HIF1A (a master regulator of the Warburg effect). Further explanatory research in MCF-7 cells showed no impact of cadmium exposure on molecular and biochemical markers of the Warburg effect. However, long-term exposure to a low and environmentally relevant concentration of cadmium led to the accumulation of the metal in MCF-7 cells and decreased their sensitivity to tamoxifen. To conclude, the association between cadmium and the Warburg effect was suggested in the observational study, although not confirmed in vitro. Nevertheless, cadmium seems to interfere with tamoxifen treatment which deserves further investigation in terms of its possible implication in intrinsic resistance to hormone therapy.

High temperature total consumption sample introduction system coupled to microwave plasma optical emission spectrometry (MIP-OES) for the analysis of aqueous samples

Date: 2023
Authors: Martínez, S;Sánchez, R;Todolí, JL;
References: Analytica chimica acta 1249 340948
Keywords/Products: Concentric;Concentric nebulizer;ICP;ICP-OES;Meinhard;sample introduction;TR-30-A1;
The high temperature torch integrated sample introduction system (hTISIS) is coupled to microwave plasma optical emission spectrometry (MIP-OES) for the first time. The goal of this work is to develop an accurate analysis of digested samples under continuous sample aspiration mode by coupling the hTISIS to a MIP-OES instrument. To achieve this, different operating conditions such as, nebulization flow rate, liquid flow rate and the spray chamber temperature were optimized in terms of sensitivity, limits of quantification (LOQs) and background equivalent concentration (BECs) for the determination of Ca, Cr, Cu Fe, K, Mg, Mn, Na, Pb and Zn, and these values were compared with those reported with a conventional sample introduction system. Under optimum conditions (0.8-1 L min-1, 100 ?L min-1 and 400 ?C, respectively), the hTISIS improved MIP-OES analytical figures of merit and shortened 4-times wash out times with respect to a conventional cyclonic spray chamber, reporting an enhancement factor in the sensitivity among 2-47 times and LOQs from 0.9 to 360 ?g kg-1. Once the best operating conditions were set, the magnitude of the interference caused by 15 different acid matrices (2, 5 and 10% w/w of HNO3, H2SO4, HCl and mixtures of HNO3 with H2SO4 and HNO3 with HCl) was significantly lower for the former device. Finally, 6 different digested oily samples (used cooking oil, animal fat, corn oil and the same samples after a filtration step) were analyzed by means of an external calibration approach based on the use of multielemental standards prepared in 3% (w/w) HCl solution. The obtained results were compared against those supplied by a conventional methodology employing an inductively coupled plasma optical emission spectrometry, ICP-OES, instrument. It was clearly concluded that the hTISIS coupled to MIP-OES afforded similar concentrations as compared to the conventional methodology.

The Toxicological Analysis and Toxicological Risk Assessment of Chosen Elemental Impurities (Ag, Au, Co, Cr, Cs, Li, Mo, Se, and Sr) in Green Tea (Camellia sinensis (L.)) Infusions

Date: 2023
Authors: Frydrych, A;Noga, M;Milan, J;Kondratowicz-Pietruszka, E;Kro?niak, M;Jurowski, K;
References: Nutrients 15 ~
Keywords/Products: ICP;ICP-MS;Meinhard;
Our study's objective is to evaluate the potential health effects of elemental impurities (Ag, Au, Co, Cr, Cs, Li, Mo, Se, and Sr) found in green tea infusions (Camellia sinensis (L.)). The ICP-MS-based methodology was employed for elemental analysis and a detailed health risk evaluation based on weekly consumption (?g/L of infusion/week). The provisional tolerable weekly intake (PTWI), established by the Joint FAO Expert Committee on infusion/week/month based on existing literature data, was then compared to the subjects with data from the available literature. The exposure of the study items to Co ranged from 0.07904 to 0.85421 ?g/day. On the contrary, the ICH (International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use) guidelines state that the established permitted daily exposure PDE (oral exposure) for Co is 50 ?g/day. The PDE of lithium is around 560 ?g/day, and according to our study, the estimated daily exposure of the evaluated products to Li fell between 0.0185 and 0.7170 ?g/day. Our research also revealed modest concentrations of Cs (0.399-2.654 ?g/L), Mo (0.0113-0.107 ?g/L), and Sr (9.848-22.331 ?g/L) in infusions. The recognized PDE for molybdenum is approximately 3400 ?g/day. Only two samples contained silver, and when considering daily consumption, the predicted daily exposure to Ag is between 4.4994 and 0.03122 ?g/day. The amounts of all evaluated elements in a daily dose of green tea infusions should not harm the consumer's health. Further considerations should take aspects, such as constant change and environmental pollution, into account.

Cerebral iron deficiency may induce depression through downregulation of the hippocampal glucocorticoid-glucocorticoid receptor signaling pathway

Date: 2023
Authors: Zhang, H;He, L;Li, S;Zhai, M;Ma, S;Jin, G;Li, M;Zhou, F;Tian, H;Nuerkaman, T;Sun, Q;Zhang, Y;Hou, J;Sun, G;Yin, S;
References: Journal of affective disorders ~ ~
Keywords/Products: Agilent;ICP;ICP-MS;Meinhard;
Iron is a trace essential element to sustain the normal neurological function of human. Many researches had reported the involvement of iron deficiency (ID) in neural development and cognitive functions. However, the role of ID in pathogenesis of depression and its underlying mechanism are still unclear.In this study, we first used chronic unpredicted mild stress (CUMS) and iron deprivation mouse models to clarify the pathogenesis role of cerebral ID in depression. Then the role of hippocampal glucocorticoid (GC)-glucocorticoid receptor (GR) pathway in cerebral ID induced depression were elucidated in iron deprivation mice and iron deficiency anemia patients.Our results revealed that both CUMS and iron deprivation could induce cerebral ID in mice, and combination of iron deprivation and CUMS could accelerate the onset and aggravate the symptoms of depression in mice. In hippocampus, ID led to neuronal injury and neurogenesis decrease, which might be related to downregulation of GC-GR signaling pathway caused GR dysfunction, thereby inhibiting the negative feedback regulation function of hippocampus on hypothalamic-pituitary-adrenal (HPA) axis. Moreover, the overactivity of HPA axis in iron deprivation mice and iron deficiency anemia patients also confirmed GR dysfunction.Iron deprivation led to food and water intake decrease of mice, which may affect the behavioral test. In addition, we mainly evaluated the role of hippocampal ID in depression, and the number of iron deficiency anemia patients was limited.Our results identified that cerebral iron homeostasis was a key factor for maintaining mental stability.

Optimization of fermentation parameters for the production of a novel selenium enriched mulberry (Morus nigra) wine

Date: 2023
Authors: Johnson, N;Ekumah, J;Ma, Y;Akpabli-Tsigbe, N;Adade, S;Manching, X;Quaisie, J;Kwaw, E;Wang, C;
References: LWT 178 114608
Keywords/Products: ICP;ICP-MS;Meinhard;
Novel selenium (Se) access media such as wine is increasingly being improved to ease Se access and consumption. Thus, our work intended to enhance mulberry wine as a Se access medium by optimizing wine fermentation conditions using Box-Behnken design (BBD) and Response Surface Methodology (RSM). The approach combined four parameters selected from a factor screening study. Optimizing the parameters, the design predicted the best temperature as 25.01 °C, pH 4.22, °Brix 25 °Bx, and Se 299.99 ?g at a desirability of 0.939. Using these conditions, an optimized Se-enriched mulberry wine (OpSeMW) with a 9.41% alcohol by volume, 695.36 mg/100 mL total polyphenol content, and a total residual Se of 201.58 ?g was attained. It also exhibited improved characteristics regarding its physicochemical properties, color, phytochemical content, antioxidant activity, and microbiological quality compared to ordinary mulberry wine (OMW). Therefore, the optimization technique contributed to producing a Se-enriched mulberry wine as a ready-to-drink beverage to consider in achieving the Se recommended daily allowance. The optimized parameters will also serve as the benchmark for Se-enriched mulberry wine technology development and production scale-up.

New Analytical Strategy for Bioaccessibility Evaluation of Bromine and Iodine from Edible Seaweeds

Date: 2023
Authors: Scaglioni, PT;Balbinot, FP;Rondan, FS;Novo, DLR;Silva, AA;Mesko, MF;
References: Journal of agricultural and food chemistry ~ ~
Keywords/Products: Meinhard;
A strategy for determining the bioaccessibility of bromine and iodine from edible seaweeds was proposed for the first time using microwave-induced combustion (MIC) and ion chromatography coupled to mass spectrometry (IC-MS) after in vitro digestion. The concentrations of bromine and iodine in edible seaweeds using the proposed methods (MIC and IC-MS) were not statistically different from those using MIC and inductively coupled plasma mass spectrometry (p > 0.05). Trueness was assessed by recovery experiments (101-110%, relative standard deviation <10%). Following an in vitro digestion protocol, MIC was proposed as sample preparation for bioaccessible and residual fractions. Using this strategy, the mass balance totaled from 97 to 111%. No statistical difference (p > 0.05) was observed between the total concentration of bromine or iodine and their concentration in bioaccessible and residual fractions for three edible seaweed species, indicating full analyte quantification in the fractions.

Comparison and Intercorrelation of Various Bentonite Products for Oenological Properties, Elemental Compositions, Volatile Compounds and Organoleptic Attributes of White Wine

Date: 2023
Authors: Rakonczás, N;Kállai, Z;Kovács, B;Antal, G;Szabó, S;Holb, IJ;
References: Foods (Basel, Switzerland) 12 ~
Keywords/Products: Concentric;Concentric nebulizer;iCAP;ICP;ICP-OES;Meinhard;
Bentonite fining is one of the generally applied wine-making technological elements that may seriously affect wine components. The aim of this study was (i) to investigate the effect of 21 bentonite products on eight oenological parameters, 19 elements, 21 volatile organic compounds (VOCs) and 10 organoleptic properties of white wine; and (ii) to quantify intercorrelations among the parameters separately for each of the four quality attributes. Among oenological parameters, sugar, acidity, malic-, lactic-, citric acid and total phenol contents were significant among several bentonite products. The amounts of elements were the lowest in the control wine treatments (with exceptions of, e.g., Ni and Cu); and these values were significantly different from several bentonite products. The relative presence of the VOCs was above 100% for most VOCs, but it was below 100% for 1-propanol, 4-amino-1,5-pentandioic acid and butane-dioic acid, and diethyl ester in all treatments. For organoleptic parameters, the values of clearness, colour, flavour intensity and taste persistency was the lowest in the control wine treatment, while the values of flavour character, flavour quality, taste intensity, taste character, and overall harmony were the highest for the bentonite products of AP, EBE, M-SA, EBE, EBE, respectively. Results of correlation and factor analyses showed strong intercorrelative effects of bentonite fining on the four quality attributes. In conclusion, this study can help in the proper choice of a specific bentonite product in relation to complexity effects of bentonite fining.

Determination by ICP-MS of Essential and Toxic Trace Elements in Gums and Carrageenans Used as Food Additives Commercially Available in the Portuguese Market

Date: 2023
Authors: Azevedo, R;Oliveira, A;Almeida, A;Gomes, L;
References: Foods 12 1408
Keywords/Products: Concentric;Concentric Quartz Nebulizer;iCAP;ICP;ICP-MS;Meinhard;Quartz Nebulizer;Thermo;
Gums and carrageenans are food additives widely used in food preparations to improve texture and as viscosifiers. Although they are typically added in small amounts, nowadays people tend to use more and more pre-prepared food. In this work, the content of a wide panel of trace elements in commercial products were analyzed. Carrageenans and gums (n = 13) were purchased in the Portuguese market and were from European suppliers. Samples were solubilized by closed-vessel microwave-assisted acid digestion and analyzed by ICP-MS. Globally, the content of essential trace elements decreased in the following order: Fe (on average, on the order of several tens of µg/g) > Mn > Zn > Cr > Cu > Co > Se > Mo (typically < 0.1 µg/g), while the content of non-essential/toxic trace elements decreased in the following order: Al > Sr > Rb > As > Li > Cd > Pb > Hg. The consumption of these food additives can significantly contribute to the daily requirements of some essential trace elements, namely Cr and Mo. The toxic trace elements Cd, As, Pb, and Hg were below the EU regulatory limits in all analyzed samples. Additional research is needed to define the potential risk of introducing toxic trace elements into food products through the use of these additives.

Interplay Effects in the Co-Doping of ZnO Nanowires with Al and Ga Using Chemical Bath Deposition

Date: 2023
Authors: Baillard, A;Appert, E;Weber, M;Jacob, V;Roussel, H;Rapenne, L;Chaix-Pluchery, O;Consonni, V;
References: Inorganic chemistry 62 1165-1177
Keywords/Products: Meinhard;Type C;
The simultaneous co-doping of ZnO nanowires grown by chemical bath deposition is of high interest for a large number of engineering devices, but the process conditions required and the resulting physicochemical processes are still largely unknown. Herein, we show that the simultaneous co-doping of ZnO nanowires with Al and Ga following the addition of Al(NO3)3 and Ga(NO3)3 in the chemical bath operates in a narrow range of conditions in the high-pH region, where the adsorption processes of respective Al(OH)4- and Ga(OH4)- complexes on the positively charged m-plane sidewalls are driven by attractive electrostatic forces. The structural morphology and properties of ZnO nanowires are significantly affected by the co-doping and mainly governed by the effect of Al(III) species. The incorporation processes of Al and Ga dopants are characterized by significant interplay effects, and the amount of incorporated Ga dopants into ZnO nanowires is found to be larger than the amount of incorporated Al dopants owing to energetic considerations. The Al and Ga dopants are located in the bulk of ZnO nanowires, but a part of Al and Ga lies on their surfaces, their incorporation processes in the bulk being enhanced by thermal annealing under oxygen atmosphere. Eventually, the Al and Ga dopants directly affect the incorporation of hydrogen-related defects, notably by annihilating the formation of VZn-nH defect complexes. These findings present an efficient strategy to proceed with the co-doping of ZnO nanowires grown by chemical bath deposition, opening perspectives to control their electronic structure properties with a higher precision.

In vitro gastrointestinal digestion and bioavailability of lithium from processed lithiated and nonlithiated white Agaricus bisporus mushrooms

Date: 2023
Authors: Pankavec, S;Falandysz, J;Eun, H;Bara?kiewicz, D;Fernandes, AR;
References: Bipolar disorders ~ ~
Keywords/Products: Concentric;Concentric nebulizer;Meinhard;
In order to avoid side effects of lithium doses in some patients, some commonly cultivated mushroom species including A. bisporus have been successfully lithiated, with the potential to provide more acceptable sources of Li. This study assessed the in vitro release (potential bioaccessibility) and possible intake of Li using the action of artificial gastrointestinal juices on lithiated and nonlithiated (control) button mushrooms (Agaricus bisporus) that were subjected to certain modes of culinary processing.In the in vitro release study, mushrooms were processed using a number of routinely used domestic treatments including rehydrating dried mushrooms, blanching and blanching followed by pickling of fresh or frozen mushrooms. The in vitro digestion procedure used artificial gastrointestinal juices in a two-stage methodology that was adapted from 'The Bioaccessibility Research Group of Europe' method. The Li concentrations were determined using an inductively coupled argon plasma-dynamic reactive cell-mass spectrometer.Lithium was found to be more bioaccessible from caps of lithiated mushrooms compared with nonlithiated. Releases from the caps and stipes of blanched or blanched and then pickled mushrooms through gastric digestion ranged from 32?±?2 to 50?±?1% relative to the dried product and was lower for gastrointestinal digestion, which ranged from 16?±?1 to 20?±?1%.Losses of Li sustained through blanching or blanching followed by pickling of fresh mushrooms (41-87% wet weight) combined with limited accessibility during gastrointestinal release (16-55%) result in much lower bioavailability of the dose from lithiated products. A 300-g meal would provide <5% of the Li (6 mg) required for potential preventative treatments, such as reducing suicide rates and lowering dementia risk.

Placental levels of essential and non-essential trace element in relation to neonatal weight in Northwestern Spain: application of generalized additive models

Date: 2023
Authors: Álvarez-Silvares, E;Fernández-Cruz, T;Bermudez-González, M;Rubio-Cid, P;Almeida, A;Pinto, E;Seoane-Pillado, T;Martínez-Carballo, E;
References: Environmental science and pollution research international ~ ~
Keywords/Products: iCAP;ICP;ICP-MS;Meinhard;Quartz Nebulizer;Thermo;
Adequate gestational progression depends to a great extent on placental development, which can modify maternal and neonatal outcomes. Any environmental toxicant, including metals, with the capacity to affect the placenta can alter the development of the pregnancy and its outcome. The objective of this study was to correlate the placenta levels of 14 essential and non-essential elements with neonatal weight. We examined relationships between placental concentrations of arsenic, cadmium, cobalt, copper, mercury, lithium, manganese, molybdenum, nickel, lead, rubidium, selenium, strontium, and zinc from 79 low obstetric risk pregnant women in Ourense (Northwestern Spain, 42°20'12.1?N 7°51.844'O) with neonatal weight. We tested associations between placental metal concentrations and neonatal weight by conducting multivariable linear regressions using generalized linear models (GLM) and generalized additive models (GAM). While placental Co (p?=?0.03) and Sr (p?=?0.048) concentrations were associated with higher neonatal weight, concentrations of Li (p?=?0.027), Mo (p?=?0.049), and Se (p?=?0.02) in the placenta were associated with lower newborn weight. Our findings suggest that the concentration of some metals in the placenta may affect fetal growth.

Translocation of elements and fractionation of Mg, Cu, Zn, and Cd stable isotopes in a penny bun mushroom (Boletus edulis) from western Czech Republic

Date: 2023
Authors: Andronikov, AV;Andronikova, IE;Martinkova, E;Sebek, O;Stepanova, M;
References: Environmental science and pollution research international ~ ~
Keywords/Products: Agilent;Concentric;Glass Nebulizer;Meinhard;
Boletus edulis mushroom behaved as an accumulating biosystem with respect to Ag, Rb, Zn, and K. The mushroom was not an efficient accumulator of toxic As, Pb, and Cr, but Se and Cd displayed much higher concentrations in the mushroom than in the substrate samples. Other elements were bioexclusive. Different elements had different within-mushroom mobilities. The highest mobilities were displayed by Zn and Ag, and the lowest by Ti. The mushroom's fruiting body preferentially took up lighter Mg, Cu, and Cd isotopes (?26MgFB-soil?=??-0.75‰; ?65CuFB-soil?=??-0.96‰; ?114CdFB-soil?=??-0.63‰), and the heavier 66Zn isotope (?66ZnFB-soil?=?0.92‰). Positive within-mushroom Zn isotope fractionation resulted in accumulation of the heavier 66Zn (?66Zncap-stipe?=?0.12‰) in the mushroom's upper parts. Cadmium displayed virtually no within-mushroom isotope fractionation. Different parts of the fruiting body fractionated Mg and Cu isotopes differently. The middle part of the stipe (3-6 cm) was strongly depleted in the heavier 26 Mg with respect to the 0-3 cm (?26Mgstipe(3-6)-stipe(0-3)?=??-0.73‰) and 6-9 cm (?26Mgstipe(6-9)-stipe(3-6)?=?0.28‰) sections. The same stipe part was strongly enriched in the heavier 65Cu with respect to the 0-3 cm (?65Custipe(3-6)-stipe(0-3)?=?0.63‰) and 6-9 cm (?65Custipe(6-9)-stipe(3-6)?=??-0.42‰) sections. An overall tendency for the upper mushroom's parts to accumulate heavier isotopes was noted for Mg (?26Mgcap-stipe?=?0.20‰), Zn (?66Zncap-stipe?=?0.12‰), and Cd (?114Cdcap-stipe?=?0.04‰), whereas Cu showed the opposite trend (?65Cucap-stipe?=??-0.08‰).

Arsenic in Mining Areas: Environmental Contamination Routes

Date: 2023
Authors: Faria, MCDS;Hott, RC;Santos, MJD;Santos, MS;Andrade, TG;Bomfeti, CA;Rocha, BA;Barbosa, F;Rodrigues, JL;
References: International journal of environmental research and public health 20 ~
Keywords/Products: Meinhard;
The emission and accumulation of toxic elements such as arsenic in various environmental compartments have become increasingly frequent primarily due to anthropogenic actions such as those observed in agricultural, industrial, and mining activities. An example of environmental arsenic contamination in Brazil exists in the city of Paracatu, MG, due to the operation of a gold mine. The aim of this work is to evaluate the routes and effects of arsenic contamination in environmental compartments (air, water, and soil) and environmental organisms (fish and vegetables) from mining regions as well as the trophic transfer of the element for a risk assessment of the population. In this study, high levels of arsenic were found in the waters of the Rico stream ranging from 4.05 µg/L during the summer season to 72.4 µg/L during the winter season. Moreover, the highest As concentration was 1.668 mg kg-1 in soil samples, which are influenced by seasonal variation and by proximity to the gold mine. Inorganic and organic arsenic species were found above the allowed limit in biological samples, indicating the transfer of arsenic found in the environment and demonstrating a great risk to the population exposed to this area. This study demonstrates the importance of environmental monitoring to diagnose contamination and encourage the search for new interventions and risk assessments for the population.

Artisanal Gem Mining in Brazil: A Source of Genotoxicity and Exposure to Toxic Elements

Date: 2023
Authors: Santos, APR;Silva, LZ;Freire, BM;da Silva Faria, MC;Batista, BL;Rocha, BA;Barbosa, F;Rodrigues, JL;
References: International journal of environmental research and public health 20 ~
Keywords/Products: Meinhard;
Environmental and occupational exposure to toxic metals has led many people around the world to have serious health problems. Mining activities contribute to an increased risk of exposure to these elements. In this work, a study of environmental biomonitoring and routes of exposure to toxic metals in a region of artisanal mining was performed. This study was carried out in the district of Taquaral de Minas, located in the Jequitinhonha Valley in the state of Minas Gerais. The valley is one of the wealthiest and highest gem-producing areas in Brazil. Five artisanal mines were sampled (Bode, Pirineu, Pinheira, Lajedo, and Marmita). Several potentially toxic metals (Be, Zn, Mn, Ba Cd, Hg, and U) were investigated in the soils and dust over the rocks and the soils. Samples from 22 individuals occupationally exposed and 17 unexposed persons, who formed the reference group, were analyzed for trace elements by an inductively coupled plasma mass spectrometer. The genotoxicity was evaluated by the micronucleus test in buccal mucosa epithelial cells, where the following changes were scored: micronuclei (MN) binucleate (BN) cells and kariolytic (KL) cells. The MN test showed significantly increased frequencies in all alterations of exposed individuals compared to the controls (p < 0.05, Student's t-test). The urine analysis showed levels of Cr, Ni Ba, Pb, and As in the blood, which were higher than the ATSDR recommended levels. The association between the MN test and the trace element concentrations found in the blood and urine was significant (p < 0.05). The higher the number of years of working, the higher the concentrations in the blood were, due to chronic exposure. The results of the present study indicate environmental contamination and a potential risk to the health of miners, suggesting an intervention.

Speciation of selenium in fresh and cooked commonly consumed fish in Thailand

Date: 2023
Authors: Singhato, A;Judprasong, K;Sridonpai, P;Laitip, N;Ornthai, N;Yafa, C;
References: Journal of Food Composition and Analysis 120 105303
Keywords/Products: Meinhard;
Fish are an important protein source commonly consumed by the Thai people due to their ready availability and affordability in local markets. Fish are also good sources of selenium (Se), an essential trace element that plays a key role in human health. This study investigated the ten most commonly consumed freshwater and marine fish in Thailand in terms of their chemical forms of Se as prepared fresh, boiled, or fried. Organic forms of Se including selenomethionine (SeMet) and selenocystine (SeCys2) as well as the inorganic forms of selenate (Se[VI]) and selenite (Se[IV]) were assessed using High-Performance Liquid Chromatograph coupled with Plasma Triple Quadrupole Mass Spectrometry. All fish species had Se(VI) and Se(IV) below the limit of detection. For fresh fish, mixed results indicated the major forms were SeMet and SeCys2. However for boiled and fried fish, SeMet was the major Se form. Fresh and fried longtail tuna were significantly higher in SeMet compared to the other fish (p < 0.05). Boiled short-bodied mackerel was significantly higher in SeMet compared to the other fish (p < 0.05). For SeCys2, fresh giant sea perch and fresh Indo-pacific Spanish mackerel, boiled short-bodied mackerel, fried striped snakehead, and fried Indo-pacific Spanish mackerel had significantly higher SeCys2 concentrations compared to the other fish using the same cooking methods (p < 0.05). Overall, therefore, most fish species commonly consumed in Thailand contained organic Se (SeMet and/or SeCys2) as the major form of Se.