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Pesticide contamination poses significant threats to both humans and the environment, with residues frequently detected in surface waters worldwide. This study compares the effectiveness of passive samplers (POCIS and Chemcatcher) and grab sampling coupled with Stir-Bar Sorptive Extraction (SBSE) and Solid-Phase Extraction (SPE) for monitoring pesticides in surface waters. The comparative study was conducted at three sites in Victoria, Australia, representing different land uses. A total of 230 pesticides were screened, with 79 different pesticides detected overall. SBSE extracted the highest number of pesticides from grab samples, followed by SPE and passive samplers. The study highlights the complementarity of different sampling and extraction techniques in detecting a wide range of pesticides. The study also explores the suitability of these techniques for citizen science applications, emphasizing the importance of selecting appropriate methods based on specific research objectives and available resources. The findings underscore the need for a tiered approach, combining passive samplers for initial screening and grab sampling for quantitative analysis, to develop a robust monitoring strategy for protecting water quality.

Essential oils from species of the genus Varronia (Boraginaceae) are recognized for their chemical diversity and biological potential; however, phytochemical information on Varronia crenata Ruiz & Pav. remains scarce, despite its wide distribution in the Andean region. The aim of this study was to provide the first chemical and enantioselective characterization of the essential oil obtained from the leaves of V. crenata growing in Ecuador. Qualitative and quantitative analyses were carried out by GC-MS and GC-FID, respectively, using two columns with stationary phases of contrasting polarity. Compounds were identified by matching linear retention indices and mass spectra to literature references and quantified by external calibration using relative response factors (RRFs) calculated for each compound based on its combustion enthalpy. The most abundant constituents (≥3.0% on average between the two columns) of the essential oil of V. crenata, both in the nonpolar and polar stationary phases, were germacrene D (18.4%), (E)-β-caryophyllene (13.3%), α-copaene (10.4%), tricyclene (9.3%), δ-cadinene (8.9%), and α-pinene (8.3%). The volatile fraction was dominated by sesquiterpenes (60.2%) and monoterpenes (22.1%), while other chemical families were present in minor proportions. The enantioselective analysis was performed on two different columns, coated with stationary phases based on β-cyclodextrins: 2,3-diacetyl-6-tert-butyl-dimethylsilyl-β-cyclodextrin and 2,3-diethyl-6-tert-butyl-dimethylsilyl-β-cyclodextrin. Nine chiral compounds were analyzed; among them, (1R,5R)-(+)-α-pinene, (1R,5R)-(+)-sabinene, and (S)-(+)-β-phellandrene were detected as enantiomerically pure, while the other metabolites presented scalemic mixtures. Overall, the high content of bioactive sesquiterpenes and the observed stereochemical complexity highlight the potential pharmaceutical and agricultural relevance of V. crenata essential oil, while also providing novel chemotaxonomic information for the genus.

The drug-encapsulated hybrid hydrogels possessed several expected properties, including porous microstructure, conductivity, adhesive strength, antioxidant activity, antibacterial properties, and cytocompatibility, and have great potential in biomedical applications, such as skin wound hydrogel dressings and bio-adhesives. In this paper, the quercetin-loaded hybrid hydrogels (SSA-QRs) were fabricated using silk fibroin (SF), alginate, and silver-doped reduced graphene oxide (Ag@rGO) nanosheets, incorporating quercetin-encapsulated PF-127 (PF127-QR) micelles. Scanning electron microscopy (SEM) images confirmed that the fabricated hybrid hydrogels possessed an interconnected porous microstructure. The mechanical properties of hydrogels could be regulated by adjusting the content of incorporated Ag@rGO nanosheets and PF127-QR micelles. Furthermore, the obtained SSA-QR hydrogels displayed the expected swelling properties, and the swelling rates could reach 1200-1700% in 120 min, in the equilibrium state. The fabricated SSA-QR hydrogels possessed apparent conductivity and self-healing ability. In addition, SSA-QR hydrogels exhibited strong adhesive performance on the surface of different materials, including skin, metal, wood, plastic, and glass. The typical antibacterial testing using Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli) confirmed the excellent antibacterial activities of SSA-QR hydrogels. Moreover, SSA-QR hydrogels displayed good antioxidant ability and intracellular ROS scavenging ability. However, the increased content of Ag@rGO nanosheets could cause a great increase in the hemolysis ratio for SSA-QR hydrogels. Fluorescent images, cell counting kit-8 (CCK-8) assay, and cell scratch testing confirmed their excellent cytocompatibility and cell pro-migration ability. The available results demonstrated a facile strategy to prepare the quercetin-loaded hydrogel for applications of wound hydrogel dressing and bio-adhesives.

A series of amides of 1-(2-pyridyl)-5-arylpyrazole-3-carboxylic acids has been synthesized. Complexes of synthesized ligands with salts of 4f- and 5f-elements were obtained. The composition of the complexes in the gas phase, solution, and solid state has been studied. The luminescence parameters of europium complexes in solution have been determined.

N,N-Dimethylformamide (DMF) has been a cornerstone solvent in both peptide and organic synthesis due to its excellent solubilizing properties and chemical stability. However, its use has raised significant health and environmental concerns. DMF is classified as a substance of very high concern (SVHC) by the European Chemicals Agency (ECHA) due to its reproductive toxicity and potential for skin absorption, leading to liver damage upon prolonged exposure. Consequently, restrictions on its use have been introduced, encouraging the scientific community to seek safer, more sustainable alternatives. This review provides a comprehensive analysis of the existing literature on alternative solvents to DMF, identifying current gaps or problems, and offering recommendations for future research.

The tardigrade Ramazzottius varieornatus exhibits extraordinary resilience to extreme environmental stresses, yet the functional diversity of its proteome remains largely unexplored. In this study, the structural and biochemical characterization of RvCA5, an atypical α-carbonic anhydrase (CA) identified in R. varieornatus, is presented. Expression analysis in E. coli revealed the spontaneous formation of a truncated RvCA5 species, which was confirmed to be unrelated to signal peptide cleavage. RvCA5 exhibited distinct structural features, including extended intrinsically disordered regions (IDRs) at both termini. Unlike canonical α-CAs, RvCA5 exhibited negligible CO₂ hydration activity, which was partially enhanced by the removal of the N-terminal IDR, suggesting that this region acts as a dynamic entropic barrier hindering substrate diffusion. RvCA5 possesses multiple surface-exposed reactive cysteine residues, resembling the redox-sensing human CA 3. Notably, consistent with a predicted nuclear localization signal, in silico modeling predicted that RvCA5 can bind DNA via a positively charged patch near the C-terminal IDR. The DNA-binding capability of RvCA5 was experimentally demonstrated by electrophoretic mobility shift assays. Collectively, these findings suggest that RvCA5 potentially functions as a redox-responsive transcriptional regulator.

This study used high-pressure extraction to obtain antioxidant-rich fractions from Desmodium canadense leaves harvested at five vegetation phases (intensive growing to end of blooming) and to evaluate their antioxidant activity and phytochemical profile. Supercritical CO₂ extraction recovered lipophilic compounds, with the highest yield at massive flowering. The remaining plant material was fractionated by pressurized liquid extraction (PLE) using acetone, ethanol, and water; the highest PLE yield was achieved with water (16.54 g/100 g DW) at the bud formation stage. Antioxidant capacity was measured using total phenolic content (TPC) and ABTS^•+, CUPRAC, and ORAC assays. Overall, ethanol PLE extracts showed the strongest antioxidant properties: maximum TPC (282.1 mg GAE/gE) and ABTS^•+ (1010 mg TE/gE) at massive flowering, and highest CUPRAC (853.3 mg TE/gE) and ORAC (1882 mg TE/gE) at bud formation. UPLC-Q-TOF-MS/MS profiling identified 37 compounds, mainly C-glycosyl flavones, flavonol O-glycosides, hydroxycinnamic acid derivatives, and low molecular weight organic acids. Water extracts were rich in low molecular weight organic acids, while acetone and ethanol extracts contained the highest flavonoid levels. Citric acid and vitexin were the most abundant compounds. The findings indicate that D. canadense leaves, especially harvested at budding through massive flowering, are a promising source of flavonoid-rich antioxidant extracts for nutraceutical and functional food applications.

RNA viruses pose a persistent global threat due to their high mutation rates, zoonotic potential, and rapid adaptability. Emergence events have risen steadily, as demonstrated by major outbreaks caused by Influenza A, Ebola, Zika, and Chikungunya viruses, followed by the coronavirus epidemics of Severe Acute Respiratory Syndrome coronavirus (SARS-CoV-1) and Middle East Respiratory Syndrome Coronavirus (MERS-CoV) and culminating in the COVID-19 pandemic. These characteristics frequently compromise the durability of existing vaccines and antiviral therapies, highlighting the urgent need for new antiviral agents. Alkaloids, a structurally diverse class of nitrogen-containing natural compounds, have gained attention for their ability to interfere with multiple stages of the viral life cycle, including entry, replication, protein synthesis, and host immune modulation. To our knowledge, this review compiles all currently reported alkaloids with antiviral activity against RNA viruses and summarizes their proposed mechanisms of action, distinguishing evidence from in vitro, in vivo, and in silico studies. Quaternary alkaloids are discussed separately because their permanent ionic charge enables distinctive interactions with membranes and host pathways. Although many findings are promising, clinical translation remains limited by incomplete mechanistic validation, scarce in vivo data, suboptimal bioavailability, narrow therapeutic windows, and inconsistent experimental methodologies. To advance the field, future research should prioritize RT-qPCR-based antiviral evaluation to accurately quantify viral replication, incorporate mechanistic assays to clarify modes of action, apply structure-activity relationship (SAR) approaches for rational optimization, and expand in vivo pharmacokinetic and efficacy studies to assess therapeutic feasibility. Overall, alkaloids represent a promising yet underdeveloped reservoir for next-generation antiviral discovery against rapidly evolving RNA viruses.

The accurate modeling of carbohydrates is challenged by conformational flexibility, hydration, and many-body electrostatics. In this work, a polarizable bond dipole potential for carbohydrates (PBDPC25) is presented, in which C-O, O-H, and C-H bonds are represented as intrinsically polarizable dipoles. Electrostatic interactions are described through bond dipole coupling, with an orbital overlap contribution introduced to account for hydrogen bonding. For carbohydrate monomers, PBDPC25 reproduces conformational energies with a root-mean-square error (RMSE) of 2.13 kcal/mol. This accuracy exceeds that of GLYCAM06 (2.87 kcal/mol) and CHARMM36 (3.74 kcal/mol). It is also slightly better than the polarizable AMOEBA force field (2.82 kcal/mol). Optimized geometries are maintained within 0.15 Å of benchmark reference structures. This level of agreement is comparable to GLYCAM06 (0.21 Å) and close to CHARMM36 and AMOEBA (both 0.14 Å). Molecular dipole moments show excellent agreement with the reference data. Correlation coefficients exceed R² > 0.98. For carbohydrate-water clusters, hydration energies, including many-body contributions, are predicted with an RMSE of 3.50 kcal/mol. This represents a substantial improvement over GLYCAM06, CHARMM36, and AMOEBA. These results demonstrate that PBDPC25 provides a reliable framework for modeling carbohydrate conformations and local hydration effects.

This paper proposes a valorization approach for solid lavender residue, a by-product of the essential oil industry. The biomass residue was carbonized at atmospheric pressure and two temperatures (450 °C and 650 °C), followed by solvothermal modification with zinc ions (Zn²⁺, 3 and 5 mmol). The effects of temperature and Zn²⁺ incorporation on the elemental composition and morphology of the resulting biochar were examined using X-ray Fluorescence (XRF), Fourier Transform Infrared (FTIR) spectroscopy, and Scanning Electron Microscopy/Energy-Dispersive X-ray Spectroscopy (SEM/EDS) analyses. The applied Zn²⁺ modification was effective at both concentrations for the biochar obtained at both carbonization temperatures. However, a more uniform metal ion distribution was observed at 3 mmol, while at 5 mmol, a partial particle agglomeration occurred. Progressive degradation of the O-H, C=O, and C-O groups with increasing temperature and the presence of Zn-O-related interactions was observed. The results demonstrated consistent and reproducible trends, suggesting that controlled carbonization combined with Zn²⁺ incorporation can convert lavender residues into modified carbonaceous materials.