Search Results (2,700)

Dysphania ambrosioides is a widely distributed species with a traditional use in folk medicine, but it exhibits marked chemical variability that limits its standardization. This study is the first to characterize the essential oil (EO) of three Ecuadorian populations—Arenillas (ARE), Pasaje (PAS) and Piñas (PIN)—using gas chromatography–mass spectrometry/flame ionization detection (GC-MS/FID), and to correlate its composition with edaphic properties and antioxidant activity. Chemical profiles revealed three distinct chemotypes: ARE (α-terpinene 65.35%, o-cymene 24.83% and ascaridole 3.30%), PAS (α-terpinene 56.31%, o-cymene 10.09% and ascaridole 10.84%) and PIN (α-terpinene 56.89%, o-cymene 17.07% and ascaridole 7.60%). The EO yield was low (0.030–0.064% w/w), coinciding with acidic and nutrient-poor soils. On the other hand, PAS, with its neutral soil and high nitrogen, produced the highest number of oxygenated compounds. Only PAS exhibited strong ABTS radical-scavenging activity (SC₅₀ = 37.99 ± 1.01 µg/mL). In contrast, ARE showed weak activity (SC₅₀ = 424 ± 1.01 µg/mL), while PIN showed moderate activity (SC₅₀ = 112.26 ± 1.01 µg/mL), which was correlated with its high total phenol content (298.48 mg EAG/L). The 2,2-diphenyl-1-picrylhydrazyl (DPPH) activity was low in all samples. Principal component analysis (PCA) confirmed clear separation of the chemotypes, which was linked to edaphic factors such as pH, heavy metals (Cu, Fe and Mn) and organic matter. These findings suggest that edaphic conditions may modulate the chemical composition and antioxidant activity of D. ambrosioides, indicating a potential approach for the sustainable selection of plant material. Full article

The Yawan gold deposit, located in the Western Qinling Orogen, contains gold mineralisation that is predominantly controlled by approximately east-west-trending fault systems. This study integrates field geology, petrography, cathodoluminescence imaging, electron probe microanalysis of gold-bearing minerals (pyrite and arsenopyrite), and in situ laser ablation U-Pb dating of calcite to constrain the timing of mineralisation and to elucidate the mechanisms of gold enrichment. This study reveals that the deposit is significantly structurally controlled and comprises two discrete mineralisation stages: a quartz-pyrite (Py1)-arsenopyrite (Apy1)-chalcopyrite assemblage (Stage 1), and a quartz-calcite-pyrite (Py2)-arsenopyrite (Apy2)-stibnite-sphalerite-galena assemblage (Stage 2). Py1 displays distinct zonation, with rim As contents notably higher than core values, while Co and Ni contents gradually decrease from core to rim. Py2 is characterised by high As (0.00%–4.72%), low Fe/S ratios, and a porous texture, containing gold and arsenopyrite inclusions. Invisible gold occurs in lattice-bound form in both Py1 and Py2. The As-Fe-S ternary diagram of pyrite indicates that Au⁺ likely entered the crystal lattice as a solid solution. Arsenopyrite geothermometry yields a mineralisation temperature of 389 ± 44 °C, and sulfur fugacity (ƒS₂) decreased markedly from Stage 1 to Stage 2. Combined with the S and Fe characteristics of pyrite, these features support a medium-temperature metamorphic hydrothermal environment. U-Pb dating of calcite from Stage 2 yields an age of 215.6 ± 7.1 Ma. In summary, the Yawan gold deposit belongs to the orogenic gold system, with its gold precipitation and enrichment controlled by sulfidation triggered by Late Triassic tectono-fluid activity. Full article

This study investigates 49 gold solidi issued between the 4th and 5th century AD to determine their chemical composition. The coins were first catalogued by recording mass, diameter, and thickness. All specimens underwent non-destructive µ-EDXRF analysis to identify main elements, followed by semi-quantitative fineness evaluation. To validate these results, six coins were randomly micro-sampled: material was dissolved in aqua regia and analysed by ICP-AES for gold quantification and ICP-MS for high precision trace element determination. The non-destructive analyses showed consistently high gold percentages, confirming authenticity and the extensive use of this noble metal during the studied period. Two distinct groups were identified based on the XRF Pt/Pd ratio, suggesting the use of gold from different sources. Comparison of μ-EDXRF and ICP-AES gold contents shows no statistically significant differences; however, this apparent agreement should be interpreted cautiously, as it mainly reflects the limited resolving power of ICP-AES at very high gold concentrations rather than definitive evidence for the absence of surface-related effects. Trace elements analysis detected low concentrations of Cu, Sn, and Pb suggesting the use of alluvial gold for minting. The presence and correlation of terrigenous elements (Al, Ca, Ti, Cr, Mn, Fe, Ni, Zn, Sr) indicate soil as the burial site. Full article

Dilovasi district of Kocaeli is one of the largest industrial regions, and due to its high production capacity and industrial waste, the soil heavy metal levels in this region are exceptionally high. Consequently, this study focuses on essential elements (B, Ca, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Zn) and non-essential elements that are considered toxic to humans (Al, Cd, Pb), covering a total of thirteen elements. Accordingly, this study aims to highlight the degree of pollution in a Turkish Organized Industrial Zone located in the Dilovasi district of Kocaeli by quantifying the concentrations of the aforementioned elements in Calamintha nepeta subsp. glandulosa plants and soil samples, and by assessing their potential implications for human health. Significant accumulation of heavy metals in both soils and plant parts suggests that metal contamination, especially that of Fe (up to 1009.2 mg kg⁻¹), is a matter of great concern in the Dilovasi district. The results revealed that the concentrations (mg kg⁻¹) of Cr (23.0 ± 0.1), Fe (1292.5 ± 5.6), Pb (36.9 ± 0.1), Zn (151.2 ± 0.8), and Cd (3.6 ± 0.1) were considerably higher. However, the concentrations of Cu, Mn, and Ni were found to be within the permissible limits in accordance with the American Herbal Products Association and the World Health Organization referenced guideline values. Furthermore, heavy metal concentrations in C. nepeta subsp. glandulosa were generally higher in areas characterized by elevated soil metal levels, indicating a clear correspondence between soil contamination and plant metal content. Based on these findings, C. nepeta subsp. glandulosa, a plant with culinary and medicinal value, can be considered a useful bioindicator for assessing local heavy metal contamination. Full article

Pomegranate is valued for its abundant polyphenolic content and its capacity to promote health. In this study, pomegranate juice or pericarp extracts from two Mediterranean regions (Montenegro and Italy) were systematically and comparatively evaluated for the first time with respect to their polyphenolic composition, antioxidant capacity, and antimicrobial activity. The extraction of juice extracts was accomplished by means of the Kutscher–Steudel liquid–liquid extraction technique, which was employed to selectively recover phenolics. In contrast, the extraction of pericarp extracts from the solid matrix was achieved via Soxhlet extraction. A thorough high-performance liquid chromatography (HPLC) analysis was conducted to identify and quantify the major phenolic compounds present in the sample. This analysis revealed the presence of ellagitannin punicalagin isomers, with concentrations reaching up to 254.75 mg/g of the sample, as well as ellagic acid and gallic acid. The antioxidant potential of the samples was assessed using the antioxidant activity index (AAI) from the 2,2-diphenyl-1-picrylhydrazyl (DPPH) test and by a ferric reducing antioxidant power (FRAP) assay. Juice extracts demonstrated a range of activity levels, with AAI values ranging from 0.17 to 2.12 and FRAP values ranging from 2.49 to 19.41 mmol Fe²⁺/g. In contrast, pericarp extracts exhibited notably higher activity, with AAI values ranging from 0.18 to 27.57 and FRAP values ranging from 2.99 to 372.17 mmol Fe²⁺/g. This study demonstrates the markedly higher functional potential of pericarp extracts compared to juice extracts by linking detailed phenolic profiles with bioactivity data. Antimicrobial testing, inclusive of the determination of minimum bactericidal concentration (MBC), demonstrated that certain pericarp extracts manifested bactericidal properties at low concentrations against selected clinically pertinent strains, including methicillin-resistant Staphylococcus aureus (0.109% p/v), methicillin-sensitive S. aureus (0.109% p/v), carbapenem-resistant Acinetobacter baumannii (0.109% p/v), and Escherichia coli (0.563% p/v). Candida albicans and Klebsiella pneumoniae strains exhibited minimal sensitivity to these extracts. The findings indicate that pomegranate pericarp is a valuable by-product, and they demonstrate the potential of both juice and pericarp extracts as functional ingredients. Full article

In this work, the characteristic temperatures (solidus and liquidus) of selected lead blast furnace slags were investigated using in situ high-temperature optical microscopy. The effects of the basicity of the slag (CaO/SiO₂), the Fe/SiO₂ ratio, and the Zn content were investigated. The deformation temperature associated with the rounding of the sample edges and the temperature at which 75% of the sample height decreases were experimentally considered as the solidus and liquidus temperatures, respectively. The pseudoternary phase diagrams CaO-SiO₂-Fe_0.63Zn_0.37O and FeO-Ca_0.54Si_0.46O_1.46-ZnO were calculated, along with the crystallization curves, using the thermodynamic software FactSage to estimate the characteristic temperatures and phase evolution during the cooling of the slag. The difference between the calculated and experimental solidus and liquidus temperatures was about 70 °C. The results of XRD, SEM, and DSC analysis at high temperatures showed that spinel (ZnFe₂O₄), melilite (Ca₂ZnSi₂O₇), and andradite (Ca₃Fe₂Si₃O₁₂) were the base crystals for all slag samples. The liquidus temperature increases with decreasing slag basicity (CaO/SiO₂), while the liquidus temperature increases with increasing Fe/SiO₂ ratio or Zn content. Full article

Seed vigor is a key agronomic trait that integrates germination capacity and seedling establishment, critically influencing rice productivity. Inositol hexakisphosphate (IP₆) serves as a major phosphorus reservoir in seeds, yet its regulatory mechanism in seed vigor remains unclear. Here, we demonstrate that exogenous IP₆ application inhibited seed germination and seedling growth of japonica rice (Oryza sativa L. ssp. japonica cv. Zhonghua11) in a dose-dependent manner; 10 mM IP₆ reduced seed germination by 100%, while 100 μM IP₆ suppressed primary root length by 33.6% compared to the control. This inhibitory effect is likely mediated by antagonizing auxin signaling, as supported by suppressed DR5::GUS expression and altered transcription of auxin-responsive genes. OsIPK2, a key enzyme in IP₆ biosynthesis, showed high expression during early development in rice. RNA interference of OsIPK2 led to a 40.8–61.7% reduction in seed IP₆ content, 45.3–65% higher zinc (Zn) and iron (Fe) accumulation, and a 35.4–53.5% lower germination rate compared to wild-type (WT). Conversely, OsIPK2-RNAi seedlings exhibited enhanced growth and resistance to IP₆, which was associated with misregulation of auxin-responsive genes and a decrease in the repressive histone mark H3K27me3 at their loci. Furthermore, endogenous indole-3-acetic acid (IAA) levels significantly reduced in Ri-1 but unchanged in Ri-2, while abscisic acid (ABA) content and the IAA/ABA ratio remained unaltered compared to wild-type. Our findings reveal that OsIPK2 balances seed vigor and seedling development by modulating inositol phosphate metabolism, auxin responses, and epigenetic regulation, providing insights for improving seed quality in cereals. Whether the regulatory role of OsIPK2 in seed vigor is conserved across other rice subspecies requires further investigation. Full article

Wood vinegar (WV), a by-product of woody biomass pyrolysis, is increasingly used in agriculture as a sustainable biostimulant, although its effects on plant stress resistance and underlying mechanisms remain poorly understood. Recent studies propose that WV may act through a eustress-based mechanism, defined as a mild and controlled stress that activates adaptive physiological responses and enhances plant performance without causing structural or metabolic damage. This study investigated the physiological and biochemical effects of WV on strawberry plants grown under three water-deficit stress levels [no stress (NS), moderate stress (MS), and high stress (HS)] and treated with WV either via fertigation (0.5% v/v, WV₁) or foliar spray (0.2% v/v, WV₂). Gas exchange parameters (A, g_sw, E, Ci, WUE), total chlorophyll content, and nutrient balance ratios (Fe/Mn and K/Ca) were measured after a three-month growth period. PERMANOVA revealed significant effects of both WV and water-deficit stress, as well as their interaction, on most parameters. Under NS and MS conditions, WV reduced A, gsw, E, and Ci while increasing WUE, indicating enhanced water-use efficiency and improved physiological adjustment to water limitation. Chlorophyll content remained stable, demonstrating preserved photosynthetic integrity. Nutrient ratios further supported a controlled ion rebalancing associated with adaptive stress responses under NS and MS, whereas HS conditions indicated the onset of distress. Overall, the data demonstrate that WV enhances plant stress resistance primarily by inducing eustress-mediated physiological regulation rather than by directly stimulating growth. Full article

Edible insects are gaining popularity as an alternative food source, highlighting the urgent need for research on their incorporation into traditional food products. This study investigated the impact of incorporating mealworm (Tenebrio molitor) powder (MP) at 2%, 5%, and 10% levels on the nutritional, functional, and sensory properties of pasta. Proximate composition, mineral content, color parameters, cooking quality, antioxidant activity and sensory properties were evaluated. Starch digestibility fractions and predicted glycemic index (pGI) were calculated based on in vitro enzymatic hydrolysis. Results showed that 10% MP addition significantly increased protein (1.45-fold) and fat content (12-fold), enriched minerals (Fe, Zn, Mg, K), and improved antioxidant capacity (ABTS⁺·: 1.3-fold; DPPH·: 2.6-fold) and phenolic content (14.4-fold) compared to control. Color analysis revealed a decrease in lightness and an increase in redness, indicating darker tones with higher MP levels. This supplementation reduced rapidly digestible starch and pGI while increasing slowly digestible starch, suggesting benefits for glycemic control. Sensory evaluation revealed no significant differences (p > 0.05) among samples for appearance, color, taste, and overall impression, confirming good acceptability. Overall, MP fortification improved nutritional and functional properties without compromising sensory quality, supporting its application in developing high-protein, health-oriented foods. Full article

This study is based on a long-term field trial with spring barley monoculture that was established in 1970 on Gleyic Fluvisol in the Žabčice, Czech Republic. The aim was to clarify the long-term impact of straw management and mineral nitrogen (N) application on grain yields and soil aggregate stability (SAS), and to determine the mineralogical and geochemical properties crucial for soil aggregate stability changes. Variants of the experiment included a combination of incorporated and harvested straw with doses of 0, 30, 60, and 90 kg N ha⁻¹ in the form of ammonium sulphate (NH₄)₂SO₄. The incorporated straw variants had a higher average grain yield of 0.51 t ha⁻¹. The SAS values were in the range 54–64% and increased in all variants with N application compared to the 0N control. Ammonium sulphate fertilisation caused soil acidification, which was not reduced even by the incorporation of straw. SAS increased with decreasing pH value, although cation exchange capacity and exchangeable Ca²⁺ decreased, and the soil organic carbon content was similar in all variants. The relatively high content of Fe- and Al-(oxo)hydroxides extracted with ammonium oxalate (Fe_ox and Al_ox) in all samples caused an increase in SAS due to decreasing pH in the N fertilised variants compared to the control. SAS should be considered in relation to other soil properties when evaluating soil quality and fertility. Full article

This research investigates the micro-mechanisms and process control associated with the recovery of platinum group metals (PGMs) from spent automotive catalysts (SACs) through iron capturing. High-temperature smelting experiments, complemented by SEM-EDS and XRD analyses, demonstrate that PGMs spontaneously migrate from the slag phase to the iron phase, driven by interfacial energy, where they are captured to form alloy droplets with a PGM content exceeding 4 wt.%. The composite flux (CaO/H₃BO₃) markedly diminishes slag viscosity and enhances the density differential between slag and metal. This facilitates the aggregation, sedimentation, and separation of alloy droplets in accordance with Stokes’ law, thereby lowering the effective capture temperature from 1700 °C to 1500 °C and reducing energy consumption. Additionally, the flux inhibits the formation of detrimental Fe-Si alloys. PGMs form substitutional solid solutions that are uniformly dispersed within the iron matrix. This study provides both the theoretical and technical foundations necessary for the development of efficient, low-energy processes aimed at capturing and recovering Fe-PGMs alloys. Full article

Aluminothermic reduction is gaining renewed interest as an alternative processing route for the circular economy. A unique Na₂O-fluxed MnO₂ ore formulation with a small quantity of carbon reductant was applied to ensure rapid pre-reduction to MnO. This approach negates the pre-roasting step. The Na₂O flux enables the formation of the water-soluble compound, NaAlO₂, which enables recycling of Al₂O₃ for aluminium production. The addition of copper as a collector metal improved the overall alloy yield from 43% to 57%, which includes a 6% increase in Mn recovery to the alloy. The product alloy is a medium-carbon Fe–Mn–Si–Al–Cu complex ferroalloy that can be used as a steelmaking ferroalloy additive. The ferroalloy consists of 54% Mn, 19% Fe, 2.1% Si, 2.6% Al, 21% Cu, and 1.2% C. This carbon content is modulated by low-carbon solubility copper, despite the use of a graphite crucible. The formulated slag exhibits high Al₂O₃ solubility, enabling effective alloy–slag separation from the high Al₂O₃ content slag of 52% Al₂O₃. Gas–slag–metal equilibrium calculations for 1650 °C–1950 °C overlap with the experimentally produced alloy chemistry in %C and %Si, but not the %Al, as the uptake of aluminium exceeds the equilibrium calculation at 0.03–0.17%. Full article

The Sar-e-Sang lapis lazuli deposit has a mining history exceeding 5000 years, producing the world’s finest lapis lazuli. Recently, gem-quality forsterite has been discovered in the marble containing spinel, dolomite, and phlogopite at the periphery of the lapis lazuli ore body at the Pitawak mine, located east of the Sar-e-Sang deposit. The mineral assemblage indicates that the protolith of this marble is dolomite with aluminous and siliceous components. These forsterite crystals occur as colorless, transparent anhedral grains, exhibiting distinct red fluorescence under 365 nm ultraviolet light. To investigate the gemological and spectroscopic characteristics of the Pitawak mine forsterite, this study conducted and analyzed data from basic gemological analysis, electron probe microanalysis (EPMA), Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), ultraviolet–visible absorption spectroscopy (UV-VIS), Fourier-transform infrared spectroscopy (FTIR), laser Raman spectroscopy (RAMAN), and photoluminescence spectroscopy (PL) on four forsterite samples from the Pitawak mine. The analysis results reveal that the samples indicate a composition close to ideal forsterite with a crystal chemical formula of (Mg_2.00Fe_0.02)_Σ2.02Si_0.99O₄. The trace elements present include Fe, Mn, Ca, and minor amounts of Cr and Ni. The UV-VIS spectroscopy results show that the samples possess high transmittance across the visible light range with very weak absorption bands, contributing to the colorless and transparent appearance of Pitawak mine forsterite. This phenomenon is attributed to the extremely low content of chromophoric elements, which have a negligible effect on the forsterite’s color. PL spectroscopy indicates that the red fluorescence of the samples is caused by an emission peak near 642 nm. This emission peak arises from the spin-forbidden ⁴T₁ → ⁶A₁ transition of Mn²⁺ ions situated in octahedral sites within the forsterite structure. Full article

The removal of copper–cyanide complexes from cyanide gold leaching tail water poses a significant challenge, as they are difficult to eliminate and risk causing secondary pollution. This study developed a synergistic flocculation–flotation process using the bio-collector sodium cocoyl glycinate (SCG) and the coagulant polyferric sulfate (PFS) for purification. Simulated wastewater, prepared based on actual gold mine effluent, was treated under optimized conditions of reagent dosage, a solution pH of 6–10, and a flotation time of 1–5 min, achieving high removal efficiencies of 96.48% for copper and 94.68% for total cyanide. Mechanistic studies via FT-IR, Zeta potential, and XPS revealed that Fe³⁺ from PFS formed Fe-CN complexes with both free and copper-complexed cyanide. Simultaneously, copper ions coordinated with SCG to generate a hydrophobic Fe-CN-Cu-SCG ternary complex, which was subsequently removed by adsorption onto air bubbles via the hydrophobic chains of SCG. This work provides a novel, efficient, and mechanistically clear strategy for the advanced treatment of cyanide-containing tailing water with a gold content of 0.021 mg/L. Full article

Tiger nut (Cyperus esculentus L.) is a relatively neglected tuber crop with notable nutritional, functional, and ecological value. The primary objective of this study was to evaluate the biological properties and selected nutritional parameters of tiger nut tubers and oil, including antioxidant activity, total phenolic content (TPC), fatty acid (FA) profile, health-related lipid indices, and mineral composition. Methods: Natural and peeled tiger nut tubers, as well as commercially available tiger nut oil (yellow variety, Valencia, Spain), were analyzed. Antioxidant activity was measured spectrophotometrically using the DPPH method. The content of TPC was determined using the Folin–Ciocalteu assay. Fatty acid composition was analyzed by gas chromatography coupled with flame ionization detection, and these data were used to calculate the PUFA/SFA (P/S) ratio, atherogenicity (AI), thrombogenicity (TI) index, and hypocholesterolemic/hypercholesterolemic (h/H) ratio. Macro- and microelement contents were quantified using inductively coupled plasma optical emission spectrometry. Estimated daily intake (EDI), target hazard quotient (THQ), and total THQ (TTHQ) were calculated to assess potential health risks. Results: Natural tiger nut tubers exhibited substantially higher antioxidant activity and TPC compared to peeled tubers, suggesting that the peel is the primary reservoir of phenolic compounds. Strong antioxidant activity was observed in tiger nut oil (64.82 ± 2.59 mg TEAC/L). Oleic acid (C18:1cis n-9) was identified as the predominant FA across all samples, thus contributing positively to favorable health lipid indices (P/S > 0.50, low AI and TI, high h/H ratio). Potassium was the most abundant macroelement in natural and peeled tiger nut tubers. The overall trend of microelement levels in these samples was as follows: Al > Fe > Zn > Cu > Sr > Mn > Li > Ba > Se > As > Cr. All THQ and TTHQ values were below 1, indicating no appreciable health risk associated with consumption. Conclusions: These findings support the use of tiger nuts as a functionally valuable ingredient in health-oriented food products. Full article