Search Results (247)

This study reports the synthesis and characterization of four novel rare earth-gallic acid complexes, Sm(Gal)₃·4H₂O, Eu(Gal)₃·4H₂O, Tb(Gal)₃·4H₂O, and Dy(Gal)₃·4H₂O. These complexes were synthesized under optimized conditions (60 °C, pH 4–5) and characterized using the Ln³⁺ elemental content method, infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), mass spectrometry (MS), and fluorescence spectroscopy. IR spectra confirmed the coordination of rare earth ions (Ln³⁺) with gallic acid through carboxylate oxygen atoms. TGA revealed the thermal decomposition pathways, while MS identified the molecular ion peaks and fragmentation patterns. All complexes exhibited strong luminescence under UV excitation, with emission peaks corresponding to characteristic transitions of Sm³⁺, Eu³⁺, Tb³⁺, and Dy³⁺. Biological assays demonstrated significant antimicrobial activity against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa, with Dy(Gal)₃·4H₂O showing the highest efficacy. Additionally, the complexes displayed inhibitory effects on MCF7 breast cancer cells, with Tb(Gal)₃·4H₂O exhibiting the lowest IC₅₀ value (11.3 µM). These findings suggest that rare earth metal complexes with gallic acid have potential applications in biomedical fields, particularly as antimicrobial and anticancer agents. Full article

Thanks to several components with health-promoting properties, mushrooms are recognized as a practical functional food and a valuable source of nutrients for the food industry. Ergosterol, the major sterol in edible mushrooms and a precursor of vitamin D2 with proven pharmacological activity and nutritional value, has become a very important topic in chemical and medical research. The main objectives of this study were to determine the ergosterol content in different species of Serbian wild mushrooms and in commercial mushrooms from Korean and Serbian grocery stores using square-wave voltammetry, to compare the concentrations in different parts of white button mushrooms, and to determine a possible relationship between Zn, Cu and Fe and ergosterol contents. The ergosterol contents varied between 0.01 and 7.04 mg/g (dry mass) of the mushrooms and were generally higher in cultivated mushrooms than in wild mushrooms. In addition, the ergosterol concentration was higher in the stems than in the caps of the mushrooms examined. Iron, Zn and Cu contents varied between the mushroom species at 8.5–479.9, 13.1–149.7 and 1.62–93.03 mg/kg, respectively, and principal component analysis (PCA) extracted two factors explaining 79.14% of the total variance, suggesting a direct relationship between iron and ergosterol content. This is the first comprehensive study to analyze and evaluate ergosterol concentrations in edible mushrooms from Korea and Serbia. Full article

Background: Root canal sealers remain in long-term contact with dental tissues, raising concerns about their potential adverse effects. Methods: This study evaluates the physicochemical properties and ion-release profiles of three dental materials: zinc oxide/eugenol-based sealer, zinc phosphate cement (luting agent), and glass-ionomer cement (restorative material) under acidic (pH 4) and neutral (pH 7) conditions over 24 h and 30 days to determine their behavior and bioactivity in vitro. The materials were evaluated for their setting time, consistency, film thickness, solubility, and ion release using atomic emission spectrometry. The influence of pH and exposure time on ion release was analyzed using multiple regression analysis. Results: All tested materials met the ISO standards for their respective categories. The zinc oxide/eugenol and zinc phosphate cements released increased levels of zinc in acidic environments (pH 4), suggesting potential antimicrobial properties. The glass-ionomer cement exhibited higher silicon and strontium release under a neutral pH (pH 7), indicating potential remineralization effects. Silver from the zinc oxide/eugenol material was below the detection limit of the applied method, suggesting minimal ion release under the tested conditions. Maximum zinc release from root canal sealer occurred after 30 days at pH 4 (1.39 ± 0.26 mg), while the highest silicon release from glass-ionomer cement was observed at pH 7 after 30 days (1.03 ± 0.21 mg). Conclusions: Zinc oxide/eugenol materials exhibited increased zinc release under acidic conditions. In contrast, the restorative and luting materials demonstrated distinct ion-release patterns, aligning with their respective intended applications rather than endodontic purposes. Full article

Blood concentrations of essential trace elements can be used to diagnose conditions and diseases associated with excess or deficiency of these elements. Inductively coupled plasma mass spectrometry (ICP-MS), inductively coupled plasma atomic emission spectroscopy (ICP-AES), and graphite furnace atomic absorption spectrometry (GF-AAS) have been employed for such measurements, but maintenance and operation costs are high. X-ray fluorescence (XRF) detectability in cutaneous blood of iron (Fe), copper (Cu), zinc (Zn), and selenium (Se) was assessed as an alternative to ICP-MS. Three phantoms were made up of two polyoxymethylene (POM) plastic cylindrical cups of 0.6 mm and 1.0 mm thick walls and a 5.3 mm diameter POM cylindrical insert. Six aqueous solutions of Fe in 0 to 500 mg/L and Cu, Zn, and Se in 0 to 50 mg/L concentrations were poured into the phantoms to simulate X-ray attenuation of skin. Measurements using an integrated X-ray tube and polycapillary X-ray lens unit generated 24 calibration lines. Detection limit intervals in mg/L were (36–100), (14–40), (3.7–10), and (2.1–3.4) for Fe, Cu, Zn, and Se, respectively. Fe was the only element with detection limits lower than its 480 mg/L median human blood concentration. The estimated radiation dose and equivalent dose to skin were below those of common radiological procedures. Applications will require further instrumental development and finding a calibration method. Full article

In the framework of lateritic material valorization, we demonstrated how the geological environment determines the mineralogical characterizations of two laterite samples, KN and LA. KN and LA originate from the Birimian and Precambrian environments, respectively. We showed that the geological criterion alone does not determine the applicability of these laterites as potential adsorbents but must be associated with their physicochemical properties. The characterizations were carried out using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Thermal analysis, and Atomic Emission Spectrometry Coupled with an Inductive Plasma Source. The major mineral phases obtained by X-ray diffraction analysis coupled with infrared analysis showed that the KN and LA laterite samples were composed of quartz (33.58% to 45.77%), kaolinite (35.64% to 17.05%), hematite (13.36% to 11.43%), and goethite (7.44% to 6.31%). The anionic exchange capacity of the KN and LA laterites ranged from 86.50 ± 3.40 to 73.91 ± 9.94 cmol(-)·kg⁻¹ and from 73.59 ± 3.02 to 64.56 ± 4.08 cmol(-)·kg⁻¹, respectively, and the cation exchange capacity values are in the order of 52.3 ± 2.3 and 58.7 ± 3.4 cmol(+)/Kg for the KN and LA samples, respectively. The specific surface values determined by the BET method were 58.65 m²/g and 41.15 m²/g for the KN and LA samples, respectively. The effects of adsorbent doses on As(III,V), Pb(II), and Cu(II) adsorption were studied. At 5 mg/L As and 15 g/L adsorbent (pH 6.5–7), arsenate removal was 99.72 ± 0.35% and 99.58 ± 0.45% for KN and LA, respectively, whereas arsenite removal reached 83.52 ± 2.21% and 98.59 ± 0.64% for LA and KN, respectively. The Pb(II) and Cu(II) removal rates were 74.20 ± 0.95% for 2.4 g/L KN and 54.18 ± 0.01% for 8 g/L KN, respectively. Based on their physicochemical and mineralogical characteristics, the KN and LA laterite samples were shown to possess a high potential as adsorbent material candidates for removing heavy metals and/or anionic species from groundwater. Full article

Transport and vehicle traffic are closely connected with particulate matter (PM) pollution, inducing various fractions into the atmosphere, some of them forming significant deposits on the surface of the car. They are washed away during carwash-inducing slurries collecting the PM deposits, which are characteristic of a large area. Crystalline PM matter was investigated by XRD coupled with polarized optical microscopy (POM). Organic matters were investigated by Fourier-Transform Infrared spectrometry (FTIR) and gas chromatography, GC-MS. Their microstructure and elemental composition were investigated by SEM-EDX. The crystalline features contain mainly quartz, calcite, and clay (muscovite and kaolinite) particles having traces of goethite and lepidocrocite. Slurry particle size distribution was established by sieving on the following meshes: 63 µm, 125 µm, 250 µm, 500 µm, 1000 µm, 2000 µm, and 4000 µm. Coarse fractions of 250–4000 μm are dominated by quartz and calcite particles. The quartz and calcite amount decreases with particle size, while the muscovite and kaolinite amount increases in the finest fractions of 0–125 μm. Organic matter was evidenced, firstly, by FTIR spectroscopy, revealing mostly CH₂; C=O, and NH₄ bonds that are more intense for the fine particulate fractions. The organic deposits form mainly amorphous crusts associated with micro- and nano-plastic particles related to the phthalates and traces of the washing detergents. Atomic Force Microscopy revealed their size range between 60 and 90 nm and evidenced nanoparticles within samples. The nanofractions adhere to the bigger particles in humid environments, assuring their immobilization to reduce their hazardous potential. Carwash slurry blending with fertile soil ensures proper grass seed germination and growth at mixtures of up to 60% slurry, allowing its sustainable reconversion as soil for landfill and dump rehabilitation, preventing the PM emission hazard. Blended compositions containing more than 60% slurry have noxious effects on the grass seeds, inhibiting their germination. Full article

Toxic metals and metalloids food contamination is a source of health risks; this study evaluated lead (Pb), cadmium (Cd), and arsenic (AS) contamination in the meat, liver, kidneys, heart, and lungs of guinea pigs raised on a farm near a mini mineral concentrator and with pastures irrigated with wastewater in the Central Andes of Peru. The risk of consuming these elements was estimated in the Peruvian population aged 2 to 85 years, whose consumption is 660 g/per capita/year. The quantification of Pb, Cd, and As was carried out via Inductively Coupled Plasma Atomic Emission Spectrometry. The heart had 3.3, 4.3, 7.3, and 81 times more Pb than the liver, lung, kidneys, and meat. The liver had 1.02, 2.22, 9.15, and 722.5 times more Cd than the kidneys, heart, lungs, and meat, respectively. The kidneys had 1.16 and 1.72 times more As than the liver and heart, respectively. The Target Hazard Quotient (TQH) and Hazard Index (HI) for Pb, Cd, and As, were <1 in the entire population, and there was no risk from their consumption. The cancer risk values found in the study are within the tolerated ranges. The findings expand the scientific basis for the safe and innocuous production of guinea pigs in the Central Andes of Peru and provide evidence to establish limits on water, soil, pastures, and agri-food products. Full article

Hexavalent chromium (Cr(VI)) is toxic, carcinogenic, and harmful to biological systems. Common detection methods, such as colorimetry, atomic absorption spectrometry, ion chromatography, and biological systems, can only be used in the laboratory and do not provide real-time feedback. To address these limitations, the current study cloned the ChrB gene, which exhibits high specificity in detecting Cr(VI), and the ChrA gene, which exhibits high Cr(VI) tolerance, into Escherichia coli. This recombinant strain, ChrA–ChrB–E. coli, was integrated into a single-chamber microbial fuel cell for accurate continual monitoring over a wide range of Cr(VI) concentrations. ChrA–ChrB–E. coli thrived in temperatures from 25 °C to 45 °C and pH levels between 5 and 8. Its ability to reduce Cr(VI) remained consistent across Cr(VI) forms, carbon sources, and oxyanions. Cyclic voltammetry was employed to verify the electrical activity of the biosensor. The biosensor exhibited a detection limit of 0.0075 mg/L. Under conditions simulating the regulatory emission limit for Cr(VI) of 0.5 mg/L in industrial wastewater, the biosensor achieved a response time of 20 s during continual operation. When tested with synthetic wastewater containing Cr(VI) concentrations from 0.02 to 150 mg/L, the system exhibited high adaptability and facilitated stable monitoring (relative standard deviation ≤ 2.7%). Additionally, the biosensor’s accuracy (−1.73% to 2.5%) matched that of traditional batch methods, highlighting its suitability for real-time Cr(VI) monitoring in aquatic environments. Full article

Climate change worsens abiotic stresses, primarily due to high temperatures, which have a negative impact on avocado productivity, leading to reduced crop yields, affecting fruit set and abscission. To tackle these challenges, antioxidants such as glycine, choline, and proline can enhance plant tolerance to these stressors and minimize plant cell damage. This work aimed to use these antioxidants to improve avocado commercial yield and quality under challenging environmental conditions. This study was conducted at the experimental farm of the Polytechnic University of Valencia, Spain, to evaluate the effects of glycine, choline, and proline on ‘Hass’ Persea americana plants. The research took place during the 2022–2023 and 2023–2024 seasons in a 2.0 ha orchard, using a randomized design with two treatments: one with antioxidants and the other without. Substances were applied at specific phenological phases, as the BBCH code indicated. Tree growth parameters, including trunk diameter, height, crown diameter, and tree canopy volume, were measured using geometric formulas. Leaf samples were collected to analyze the nutrient concentrations of N, P, K, Ca, Mg, S, B, Cu, Fe, Mn, and Zn using atomic emission spectrometry. Marketable fruit yield and quality parameters such as fat, fiber, and protein content were evaluated using the Association of Official Agricultural Chemists (AOAC) methods. The results showed that antioxidants did not significantly affect tree growth but altered leaf mineral nutrient composition. N and P concentrations were reduced, while K and Ca concentrations were increased. Mn and Zn levels were higher in the treated plants, whereas Cu levels were higher in the control plants. Productivity significantly improved, with a 49% increase in fruit yield, larger fruit size, and a 7% increase in fat content, though fiber and protein remained unchanged. These results show the selective benefits of antioxidants in optimizing avocado yield and quality under stress. Full article

This study evaluates the environmental and health hazards associated with the presence of Fe, Cr, Zn, Cu, and Pb in agricultural soils from the Makkah region in western Saudi Arabia. Soil samples were collected from 32 farms predominantly cultivating dates and vegetables and analyzed for heavy metals (HMs) using inductively coupled plasma-atomic emission spectrometry (ICP-AES). Multivariate statistical analysis, Geographic Information Systems (GIS), and various contamination indices were employed. The average HM concentrations were arranged in descending order as follows: Fe (35.138 mg/kg), Zn (69.59 mg/kg), Cu (55.13 mg/kg), Cr (47.88 mg/kg), and Pb (6.09 mg/kg). Contamination indices indicated considerable enrichment of Cu and deficient to minimal enrichment for the other HMs, though a few individual samples showed higher enrichment factor (EF) values. Risk assessments revealed a low-level risk associated with HMs in Makkah soils. Multivariate analyses suggested that the HMs primarily originated from natural geological processes, with anthropogenic contributions particularly evident for Cu. Hazard index (HI) values ranged from 0.0003 to 0.0691 for adults and 0.003 to 0.6438 for children, remaining below the threshold of 1.0, which indicates no significant non-carcinogenic risk. Lifetime cancer risk estimates for Pb were below 1 × 10⁻⁶, while those for Cr ranged from 1 × 10⁻⁶ to 1 × 10⁻⁴, indicating tolerable carcinogenic risk levels with a few exceptions for Cr in children. This study is significant as it provides critical baseline data on HM contamination in agricultural soils in the Makkah region, offering insights into natural and anthropogenic contributions to soil pollution. The findings contribute to the broader understanding of environmental risk assessments and serve as a foundation for developing sustainable agricultural practices and targeted mitigation strategies to minimize health risks in regions with similar environmental conditions. Full article

This paper presents a new account of the mineralogy of the bat guano deposit in Gaura cu Muscă Cave, Locvei Mountains, Romania. The cave, which, in its main proportion, is a wet, “live” cave, has a dry portion hosting guano. Biogenic leucophosphite is one of the main compounds of the fossil bat guano association in the cave, where it occurs together with hydroxylapatite, taranakite, ardealite, calcite, quartz and illite (the 2M1 polytype). The mineral species from the cave were characterized by optical methods, scanning electron microscopy, wet-chemical analysis, X-ray powder diffraction, Fourier-transform infrared and inductively coupled plasma – atomic emission spectrometry. The crystal-chemical formula of leucophosphite from Gaura cu Muscă is [K_0.978Na_0.003(NH₄)_0.014](Al_0.085Fe_1.903Mg_0.001Mn_0.006)(PO₄)₂(OH)_0.973·2H₂O. The cell parameters calculated for the same sample are a = 9.813(6) Å, b = 9.749(6) Å, c = 9.631(9) Å and β = 102.30(2)°. The infrared spectrum affords the presence of (PO₄)³⁻, (HPO₄)²⁻, (NH₄)⁺ and (OH)⁻ ions, together with H₂O molecules. The band multiplicity on the IR absorption spectrum suggests that the phosphate groups in the structure have C_s punctual symmetry. The host deposit was formed under extremely “dry” conditions that favored a sharp decrease in the pH of solutions derived from the guano mass. Full article

The unintentional release of nanoparticles in the atmosphere and their targeted application to improve plant productivity requires detailed study. The translocation features of copper and gold nanoparticles applied by spraying in the concentration range of 1–100 mg/L in Petroselinum crispum (Mill.) tissues during a 10-day experiment were investigated. Atomic absorption spectrometry and inductively coupled plasma atomic emission spectroscopy showed that copper and gold nanoparticles applied to the leaves’ surface could accumulate in plant organs. A dose-dependent increase in the content of copper and gold in the aerial parts of parsley was revealed. The content of copper in leaves treated with nanoparticles was 1–2.3 times higher than the control, while the content of gold exceeded control values 2–116 times. The effect of nanoparticles on plants’ biochemical composition was assessed. The antioxidant tests showed an ambiguous response at exposure to metal nanoparticles. Copper nanoparticles at the applied concentration consistently reduced both chlorophyll and carotenoid content. Gold nanoparticles enhanced the chlorophyll and carotenoid level at low concentrations (1 mg/L) and significantly inhibited it at higher concentrations. The parsley exposed to nano-copper remained safe for human consumption, but parsley containing more than 14.9 mg/kg of gold may adversely affect human health. Full article

Cloud point extraction is a sample preparation technique that involves using surfactants that are not harmful to the environment. It is based on micelle formation in which the extracted compound is encapsulated in the hydrophobic core of the micelles, which are the extracting agent. The most commonly used surfactants are nonionic. The others are anionic, cationic, or zwitterionic. The effectiveness of cloud point extraction might be enhanced by the addition of neutral salts, the application of proper pH, as well as acidic conditions and temperature. This sample preparation technique may be applied to extract analytes from the following matrices, such as biological and environmental samples. Cloud point extraction may be combined with various analytical techniques and detectors such as HPLC-UV, HPLC-MS, HPLC-FLD, inductively coupled plasma–optical emission spectrometry, gas chromatography, and flame atomic absorption spectrometry. When it is combined with electrothermal atomic absorption spectrometry, the limit of quantitation is low—even of the order of ng/L. The recovery of the analyte may reach the value of 100%. Full article

Background/Objectives: Novel boron dipyrromethene derivatives with a heterocyclic, benzoxadiazole substituent were obtained as potential candidates for the photodynamic therapy (PDT) of cancers. Photochemical properties (e.g., singlet oxygen generation quantum yields (Φ_Δ), absorption, and emission spectra) and cytotoxic activity studies in normoxic and hypoxic conditions were performed to verify the potential of novel BODIPYs as photosensitizers for PDT. Methods: Obtained dyes were characterized using mass spectrometry and various NMR techniques. The relative method with Rose Bengal as a reference and 1,3-diphenylisobenzofuran as a singlet oxygen quencher was used to determine Φ_Δ values. The in vitro studies were conducted on human ovarian carcinoma (A2780) and human breast adenocarcinoma (MDA-MB-231) cells. Results: Photochemical studies showed that the presence of benzoxadiazole moiety only slightly affected the localization of the absorption maxima but resulted in fluorescence quenching compared with meso-phenyl-substituted analogs. In addition, brominated and iodinated analogs revealed a high ability to generate singlet oxygen. Anticancer studies showed high light-induced cytotoxicity of BODIPYs containing heavy atoms with very low IC₅₀ values in the 3.5–10.3 nM range. Further experiments revealed that both compounds also demonstrated phototoxic activity under hypoxic conditions. The most potent cytotoxic effect in these conditions was observed in the iodinated BODIPY analog with IC₅₀ values of about 0.3 and 0.4 μM for A2780 and MDA-MB-231 cells, respectively. Conclusions: The results of this study highlighted the advantages and some potential drawbacks of BODIPY compounds with heavy atoms and benzoxadiazole moiety as a useful scaffold in medicinal chemistry for designing new photosensitizers. Full article

Macapá City, located in the Brazilian Amazon, faces critical aquatic pollution challenges due to inadequate sanitation infrastructure, leading to metal contamination in fish within its urban water bodies. Our study evaluated the concentrations of metals (Cu, Cd, Cr, Fe, Mn, Ni, Pb, Zn, and Hg) in muscle tissues of fish from igarapés, ressaca areas, and canals. Samples were collected from six sampling sites to investigate the bioaccumulation of these metals and their potential human health risks. All metals were quantified by atomic absorption spectrometry, except Hg, which was quantified by inductively coupled plasma optical emission spectrometry. Metal concentrations were determined in three carnivorous and seven omnivorous fish species. Cd concentrations exceeded the Brazilian maximum limit established for human consumption in all fish species evaluated. The estimated daily intake (EDI) of Pb and Hg exceeded their reference doses. Our risk assessment, which combined the risk quotient (RQ) for individual metals and the risk index (RI) for metal mixtures, indicated health risks associated with the consumption of fish collected from the study areas. These results demonstrated a worrying exposure to metals (mainly Cd, Pb, and Hg), highlighting the need for environmental management measures and continuous monitoring to protect public health in vulnerable urban areas. Full article