Search Results (26,772)

Catchment characteristics significantly influence water composition in pristine mountain lakes, receiving similar atmospheric deposition. We analysed these relationships for 20 subalpine and alpine catchment–lake systems in the High Tatra Mountains (Slovakia), using a comprehensive new dataset of detailed catchment characteristics and mean water chemistry from 2021 to 2024. Redundancy analysis indicated that catchment characteristics explained 47% of the spatial variability in lake hydrochemistry. The most influential parameters were land cover (20%), terrain slope (11%), lake-to-catchment area ratio (8%), and bedrock geology (8%). Cation concentrations were dominated by Ca²⁺, while anions were dominated by HCO₃⁻. Concentrations of Na⁺, K⁺, Cl⁻, dissolved organic carbon (DOC), and total organic nitrogen (TON) were higher, while NO₃⁻ was lower, in lakes with greater soil and vegetation cover in catchments. Concentrations of Na⁺, K⁺, Mg²⁺, Ca²⁺, HCO₃⁻, Cl⁻, SO₄²⁻, silicon (Si), and DOC decreased with increasing altitude, whereas Na⁺, K⁺, SO₄²⁻, NO₃⁻, NH₄⁺, and Si increased with catchment slope. Catchment bedrock geology affected K⁺, SO₄²⁻, and Si concentrations in lake water. More than 50% of the observed variability remained unexplained, indicating that additional climatic and hydrological drivers may influence lake hydrochemistry and represent important directions for future research. Full article

Fucus vesiculosus (FV) is a brown macroalga rich in bioactive compounds with significant industrial potential. This study aimed to produce enzyme-assisted water-soluble hydrolysates from FV with optimized antioxidant activity using Box–Behnken experimental designs. Two extraction methods were evaluated: cellulase alone (FVc) and a combination of cellulase and alcalase (FVca). The optimization focused on enzyme concentration, temperature, and incubation time, measuring extraction yield, total phenolic content as determined by the Folin–Ciocalteu assay (non-specific reducing capacity index, FC-derived TPC), total antioxidant capacity (TAC), and oxygen radical absorbance capacity (ORAC). Results demonstrated that the combined dual-enzyme (FVca) treatment was highly efficient, simultaneously maximizing the extraction yield (39.41%) and the overall reducing capacity (TAC of 142.80 µmol TE/g, ORAC of 477.64 µmol TE/g, and a FC-derived TPC of 252.57 mg GAE/g). Due to its higher potential, FVca was further characterized, revealing a rich profile of essential amino acids, low-molecular-weight peptides, and a diverse phenolic profile, dominated by phloroglucinol (6.23 mg/g). In addition, the FVca hydrolysate demonstrated severe abiotic interference with the redox viability assay at 10 mg/mL in Caco-2 human colorectal adenocarcinoma cell cultures. These findings highlight that combining cellulase and alcalase effectively solubilizes key bioactive compounds, yielding a hydrolysate highly promising for industrial and biotechnological applications. Full article

This study evaluated the effects of breeder age (BA) and in ovo (IO) administration of vitamin D₃ metabolites on hatchability, body weight, bone traits, and leg health in broiler chickens. A total of 640 eggs obtained from young (YB; 29 wk) and old (OB; 52 wk) Ross 308 broiler breeder flocks were assigned on day 18 of incubation to four treatments: 25(OH)D₃, 1,25(OH)₂D₃, diluent, or non-injected. Chicks were reared under standard conditions until market age. Hatchability was not affected by BA or IO treatments. Birds derived from OBs exhibited greater hatch weight and final body weight than those derived from YBs. At market age, BA effects on bone traits were limited to greater femur length in OB birds. In contrast, IO administration of vitamin D₃ metabolites significantly enhanced bone mineralization and mechanical competence, as evidenced by higher tibial Ca, P, and Mg concentrations; increased bone ash content; a higher Seedor index; and greater breaking strength. Treated birds also exhibited shorter, narrower, and heavier long bones, indicating altered bone geometry. Furthermore, the incidence of gait abnormalities and tibial dyschondroplasia was markedly reduced, whereas femoral head necrosis remained unaffected. Among the metabolites evaluated, 25(OH)D₃ produced the most consistent improvements in final body weight, bone traits, and leg health. Overall, IO administration of vitamin D₃ metabolites, particularly 25(OH)D₃, improved bone traits and leg health at market age and may represent a practical strategy to enhance broiler welfare and production performance. Full article

Background/Objectives: Antimicrobial peptides (AMPs) in insect hemolymph are promising alternatives to conventional antibiotics, but their rapid screening from complex biological matrices remains difficult. This study aimed to develop a simple and efficient method for the enrichment and preliminary identification of putative AMPs from the hemolymph of Clanis bilineata tsingtauica larvae. Methods: Phospholipid-coated magnetic nanoparticles (Fe₃O₄@L) were prepared using membrane phospholipids identified from Enterococcus faecium by time-of-flight mass spectrometry. After nanoparticle characterization, enrichment conditions were optimized and the Fe₃O₄@L workflow was compared with a conventional ultrafiltration-electrophoresis-silver staining-mass spectrometry (UESM) method. Peptides were identified by de novo mass spectrometry, followed by sequence filtering, replicate screening, and in silico AMP prediction. Candidate peptides were chemically synthesized and evaluated for antibacterial activity, minimum inhibitory concentration (MIC), growth inhibition, morphological effects, and hemolytic activity. Results: Optimization of the Fe₃O₄@L method resulted in a 1.86-fold increase in peptide concentration in the enriched fraction. Compared with UESM, Fe₃O₄@L reduced the workflow from four steps to three and shortened processing time by 61.2%. De novo analysis generated 724 filtered peptides, of which 58 were reproducibly detected in at least two replicates, yielding five putative AMPs after activity prediction; no putative AMP was identified by UESM under the same conditions. Among the synthesized peptides, CBT-3 showed antibacterial activity against E. faecium and Escherichia coli, with MICs of 32 and 64 mg/L, respectively, and low hemolytic activity toward human erythrocytes. Conclusions: Fe₃O₄@L provides a simple and effective strategy for preliminary AMP screening from insect hemolymph, and CBT-3 represents a promising peptide candidate for further investigation. Full article

Pomegranate juice is a rich source of bioactive compounds, while its quality and organoleptic properties are influenced by the balance between sugars and organic acids. This study comparatively evaluated sweet, sour, and sweet–sour blended pomegranate juices by examining their physicochemical properties, color characteristics, phenolic content and volatile profile. Total phenolics, anthocyanins, and tannins were determined spectrophotometrically, and individual phenolics by HPLC-UV/VIS, while volatile compounds were identified using SPME-GC/MS. Significant differences (p < 0.05) were observed among juice types for all measured physicochemical and bioactive parameters. The sweet juice showed the highest total soluble solids to titratable acidity ratio (TSS/TA = 20.15) and the lowest tannin content (6.71 mg KE/L). The sour juice exhibited the highest acidity (2.28%) and tannin concentration (39.64 mg KE/L), along with lower L* and a* values. The sweet–sour juice presented a balanced TSS/TA ratio (10.50) and higher L*, a*, and b* values. It also contained the highest levels of total phenolics (363.4 mg GAE/L, 10 and 12% higher than in sour and sweet juice, respectively) and anthocyanins (342.05 mg C3G/L, 25 and 65% higher than in sweet and sour juice, respectively). The volatile profile was dominated by (Z)-3-hexen-1-ol and 1-hexanol. Principal component analysis explained 91.9% of the total variance and clearly differentiated the samples according to acidity, sugar balance, and bioactive composition. These results highlight the potential of juice blending to enhance chemical composition and functional properties. Full article

Background: The main aim of this study was to assess the effects of short-term N-acetylcysteine (NAC) supplementation on concentrations of homocysteine (Hcy) and reduced glutathione (rGSH), blood lipid profile and liver enzyme activities in endurance-trained adults, and to determine whether these effects are modified by methylenetetrahydrofolate reductase (MTHFR) C677T and glutathione S-transferase Pi 1 (GSTP1) A313G. Methods: A total of 56 males and 21 females completed a randomized, double-blind, placebo-controlled crossover trial. Participants received 1200 mg of NAC or a placebo for seven days in a crossover design. Serum Hcy and plasma rGSH concentrations were assessed using dedicated biochemical assays, while blood lipid profile and liver enzyme activities were measured using the biochemical analyzer Konelab 20i. Genotyping was conducted using TaqMan probes. A series of within-subject/between-subject repeated-measures analysis of variance (ANOVA) within a general linear model framework were performed to compare Hcy, rGSH, blood lipid profile and liver enzymes activities before and after the intervention. Results: Hcy concentrations significantly decreased following NAC supplementation (18.58 ± 5.45 µmol/L vs. 16.51 ± 4.97 µmol/L; p = 0.009), although subgroup analysis indicated that the decrease was significant only among females (15.40 ± 4.96 µmol/L vs. 13.60 ± 3.68 µmol/L; p = 0.002) without any significant effect among males. We did not observe any significant changes in rGSH, lipid profile, or liver enzyme activities. There was no interaction between NAC supplementation, MTHFR and GSTP1 genotypes and the changes noted in the parameters we analyzed. Conclusions: In conclusion, short-term NAC supplementation may reduce circulating Hcy concentrations in endurance-trained adults, particularly in females. No consistent effects were observed for rGSH, lipid profile, or liver enzyme activities. Full article

Increased herbicide use in agriculture is a major threat to adjacent aquatic and wetland ecosystems. In Morocco, the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) poses a risk to temporary ponds found in agricultural landscapes. This study used mesocosm experiments to assess the effects of 2,4-D concentration (0, 0.10, 0.20, and 0.30 mg·L⁻¹) and application timing (early vs. late in the hydrological cycle) on water quality and aquatic plant communities from forest ponds not previously exposed to herbicides. At the highest concentration (0.30 mg·L⁻¹), conductivity increased from 206 to 274 µS and pH from 7.5 to 8.4 under early application. At the same time, species richness and total abundance significantly decreased with increasing 2,4-D concentrations, with the strongest effects observed under early application. Community composition shifted markedly in response to 2,4-D, with annual and submerged species showing greater sensitivity, whereas perennial and emergent species were relatively tolerant. These findings highlight the need to adopt more sustainable agricultural practices to conserve pond biodiversity. Specifically, herbicide applications should be avoided near ponds, at high application rates, and during periods early in the hydroperiod. Lastly, land-use strategies should balance agricultural productivity with the conservation of biodiversity in temporary pond ecosystems. Full article

This study investigates how Raman peak features influence the accuracy of pollutant concentration quantification in Raman spectroscopy using feature-based machine learning. A Raman peak feature-based approach is applied to data acquired from laboratory Raman equipment for inorganic anion mixtures, with the objective of identifying processing strategies suitable for low-resolution Raman instruments. A dataset comprising nitrate, nitrite, and sulphate dissolved in water at varying concentrations was used to develop a pre-processing pipeline, train and validate models, and perform linear regression using peak- and area-based features extracted from analyte-specific spectral fingerprint regions. Signal downsampling was employed to simulate reduced spectral resolution and evaluate feature robustness under peak broadening conditions. Results indicate that peak-based regression is more sensitive to reduced peak resolution for nitrate and sulphate, whereas area-based regression produces more stable prediction errors across downsampling factors. Conversely, for nitrite, peak-based regression is less affected by downsampling, while area-based regression exhibits degraded performance. Area-based regression achieved mean absolute percentage errors below 7% and 16% for nitrate concentrations above 3833 mg/L and 1916 mg/L, respectively, and generally below 16% for sulphate concentrations above 1916 mg/L. For nitrite, peak-based regression yielded errors within 4%. Full article

Hexavalent chromium Cr(VI) is a highly toxic and mobile contaminant commonly detected in industrial effluents and groundwater, requiring efficient and scalable treatment strategies. In this study, a commercial unmodified biochar (UB) and an iron-modified biochar (IMB) were evaluated for Cr(VI) removal from aqueous solutions. Iron modification via FeCl₃ impregnation and alkaline precipitation (pH 9) increased surface iron content from 0.2% to 3.3%, based on Energy Dispersive X-ray (EDX) analysis and extractable Fe from 0.009% to 0.108% (FerroVer). X-ray Diffraction (XRD) analysis suggested the presence of iron-containing phases and Fourier Transform Infrared (FTIR) analysis indicated the appearance of an Fe-O band at 564 cm⁻¹. BET analysis showed a slight decrease in surface area from 359 to 317 m² g⁻¹, consistent with partial pore blockage following iron modification. Batch adsorption experiments (pH 2–10; initial Cr(VI) concentration 5–600 mg L⁻¹; adsorbent dosage 2 g L⁻¹) revealed a maximum Langmuir adsorption capacity of 158 mg g⁻¹ for IMB, nearly double that of UB (82 mg g⁻¹), with optimal performance at pH 4–6. At equilibrium, removal efficiencies of ~60% and ~80% were obtained for UB and IMB, respectively (C₀ = 100 mg L⁻¹; adsorbent dose = 2 g L⁻¹). Kinetics followed a pseudo-second-order model, with IMB reaching equilibrium within 8 h compared to 50 h for UB. Isotherm analysis is consistent with Langmuir behavior for UB and Freundlich behavior for IMB. The improved adsorption performance of IMB is likely associated with the increased iron content introduced during modification, demonstrating its potential as an effective adsorbent for Cr(VI) removal from water. Full article

Wild boars (Sus scrofa) are reliable bioindicator species for assessing environmental pollution. In this pilot study, we measured concentrations of arsenic (As), cadmium (Cd), copper (Cu), selenium (Se), zinc (Zn), and lead (Pb) in liver, diaphragm, and testicular tissues from wild boars collected across seven districts of Avellino province (liver/diaphragm: n = 87; testicles: n = 50). Pb reached its highest median value in the diaphragm (0.43 mg/kg w.w.; maximum 14.80 mg/kg), while Cd showed a pronounced affinity for hepatic tissue (median 0.15 mg/kg; maximum 0.62 mg/kg). Zn was the most abundant element overall, particularly in the diaphragm (median 20.51 mg/kg; maximum 46.81 mg/kg). Se concentrations were generally below the detection limit (<0.001 mg/kg), with only occasional outliers. Sex-related differences were evident: males accumulated more Pb in the liver, while females had higher levels of Cd and As. Spatial patterns identified AVMFS009 and AVAR009 as hotspots for Cu, Zn, and Cd, while AVCP003 emerged as the main hotspot for As. Overall, the results reinforce the role of wild boars as effective bioindicators in southern Italy. Full article

Background: Calcium phosphate (CaP)-based materials are widely used for bone defect repair, but their clinical utility is often limited by insufficient antibacterial activity and a lack of controlled drug-release capability. To address this gap, the present study investigates whether silver doping can simultaneously enhance the microstructural properties of mesoporous CaP and modulate its capacity to deliver amoxicillin in a controlled manner, thereby combining osteoconductive, antibacterial, and antibiotic-delivery functions in a single platform. Methods: Mesoporous CaP was synthesized via the polymer sacrificial method and doped with silver at two concentrations (0.5 and 1.0 wt%), both with and without amoxicillin loading, to isolate the individual and combined effects of silver and antibiotic incorporation. The resulting formulations were characterized by XRD, FTIR, SEM, and BET to establish structure–property relationships linking silver content to physicochemical and microstructural features, while their functional performance was assessed through amoxicillin release in PBS over 672 h and through biocompatibility testing on MG-63 osteosarcoma cells via MTT assay at 48, 72, and 120 h. Results: Silver incorporation was found to improve the microstructural properties of the mesoporous CaP and to progressively reduce cumulative amoxicillin release, from approximately 45% in undoped CaP to about 20% at the highest silver content, indicating that silver doping enables tunable, sustained drug release. This modulation of release was accompanied by a favorable biological profile: at 48 h, most formulations showed only moderate effects on MG-63 viability, with comparable IC₅₀ values across groups, while cytotoxicity declined and cell viability increased with longer incubation, reaching the highest proliferation at 120 h for all silver/amoxicillin-containing formulations. Conclusions: Together, these results demonstrate that silver doping does not compromise, and may enhance, the biocompatibility of mesoporous CaP even as it extends antibiotic release. This combination of tunable drug delivery, improved microstructure, and time-dependent biocompatibility positions silver-doped mesoporous CaP as a promising multifunctional platform for antibiotic delivery in bone regenerative medicine. Full article

Long-acting spot-on formulations are widely used for parasite control in cats, yet the pharmacokinetics of combined fluralaner and moxidectin remain incompletely defined beyond the recommended dose. This study evaluated the pharmacokinetics, absolute bioavailability, and dose proportionality of a novel fixed-combination spot-on formulation in healthy cats after topical administration of fluralaner/moxidectin at 40/2, 80/4, and 120/6 mg/kg BW, and compared intravenous administration of each compound alone or in combination. Forty-eight healthy cats were allocated to six groups of eight cats each. Non-compartmental analysis and a power model were used to characterize systemic exposure and dose proportionality. After intravenous co-administration, fluralaner exposure increased whereas moxidectin exposure decreased compared with single-agent administration, indicating a potential pharmacokinetic interaction. Topical administration produced slow absorption and sustained systemic persistence, with T_max values occurring approximately 10–18 days after dosing and quantifiable concentrations maintained throughout the 160 days sampling period. Systemic exposure increased non-proportionally across the tested dose range, and absolute bioavailability was limited and dose-dependent, ranging from 9.7% to 26.9% for fluralaner and from 10.22% to 21.28% for moxidectin. No adverse reactions were observed. These findings demonstrate nonlinear topical absorption, and prolonged systemic persistence, supporting further dose optimization and formulation development of this long-acting feline antiparasitic delivery system. Full article

Aquaculture has rapidly expanded, surpassing capture fisheries and playing a vital role in global food security. However, this growth raises environmental concerns, especially regarding nitrogen waste accumulation in recirculating aquaculture systems (RASs). Nitrogen compounds from uneaten feed and fish excreta, mainly ammonia (NH₃) and nitrite (NO₂⁻), lead to water pollution, eutrophication, and greenhouse gas emissions. This study describes the setup and the efficiency of a new photo-electrocatalytic (PEC) system in reducing nitrogen waste in a high-density RAS for rainbow trout (30 kg/m³). The PEC system, an evolution of a pure photocatalytic system, was integrated in the units of the RAS and tested for the first time in field conditions, combining photocatalysis and electrochemical oxidation to convert toxic nitrogen species (NH₃) into less harmful nitrogen forms (NO₃⁻ and N₂), aiming to mitigate both water and atmospheric pollution. Over a 4-week period, water nitrogen compounds, ammonia and greenhouse gases (carbon dioxide, nitrous oxide and methane) emitted by water were continuously monitored in two groups of three tanks (PEC vs. control). Each tank was equipped as an independent RAS unit. PEC treatment led to significantly lower NH₃ concentrations (0.96 ± 0.2 mg/L vs. 1.78 ± 0.2 mg/L, p < 0.01), lower NO₂⁻ levels and higher NO₃⁻ levels (61.77 ± 2.14 mg/L vs. 53.10 ± 2.14 mg/L, p < 0.01) in water, indicating efficient nitrogen oxidation. Gaseous emissions were also reduced: NH₃ (1.49 vs. 2.64 mg/m²/day, p < 0.05) and N₂O (1.44 vs. 2.88 mg/m²/day, p < 0.05). These results support PEC technology as a promising solution for improving nitrogen management in intensive aquaculture. Although challenges remain in optimizing energy use and scalability, PEC offers a valuable strategy for reducing environmental impact while sustaining productivity in the aquaculture industry. Full article

This study investigates the thermodynamics of binding between the affibody proteins ZTaq and anti-ZTaq across a broad temperature range, aiming to deepen the understanding of the underlying mechanisms governing their interaction. Affibodies are small, engineered proteins of notable stability and practical utility, serving as robust models for molecular recognition processes. Here, the anti-idiotypic binders ZTaq and anti-ZTaq were expressed and purified, and their interaction was characterized using isothermal titration calorimetry (ITC). The analysis revealed that the formation of the ZTaq:anti-ZTaq complex is marked by a large negative free energy of binding ΔG_b that is virtually unaffected by changes in salt concentration, in contrast to typical protein–polyelectrolyte systems where ionic strength plays a major role. Furthermore, the thermodynamic data indicated a large, negative heat capacity change ΔC_p, which is primarily attributed to conformational transitions, especially the disruption of the molten-globule-like (MG) state of anti-ZTaq above 303 K. By comparing thermodynamic and structural properties with related affibody systems, the study aims to clarify how specific sequence features contribute to the exceptional binding properties of these proteins, providing new insights into protein engineering for high-affinity molecular recognition. Full article

Red mud (RM) can be used as a fertilizer for large-scale disposal, but its low phosphorus content limits its high-value utilization. This study prepared composites of RM and biogas residue (BR) via co-pyrolysis, and adsorbed phosphorus from biogas effluent to increase the phosphorus content. The results show that composites with 25% BR addition and that were pyrolyzed at 600 °C had the highest phosphate adsorption capacity. Composites with a dosage over 50 g·L⁻¹, pH at 3, and initial phosphate concentration lower than 30 mg·L⁻¹ achieved a theoretical maximum phosphorus adsorption capacity of 2.877 mg·g⁻¹. The surfaces of the composites were enriched with functional groups, such as Fe-O, and this formed the complex of FePO₄ for phosphate adsorption incrementation. RM-BR adsorption of phosphate satisfied the pseudo-second-order kinetic equation, and the adsorption constant was up to 0.9949. The adsorption results of phosphorus by the composites can also be well fitted by the Langmuir models (R² = 0.969 and 0.991), indicating that the composites were more inclined to a monolayer adsorption mode. Thus, chemical precipitation was the major way for phosphate adsorption. Furthermore, the environmental impact of the biogas slurry that was disposed of with the composites in this study was lower compared to the traditional coagulation precipitation process. Above all, this study established a practical method for adsorbent preparation of RM for phosphorus recovery from biogas slurry. Full article