Search Results (465)

Deep eutectic solvents (DES) emerge as sustainable alternatives for antioxidant polyphenol extraction; however, their analytical performance and compatibility with antioxidant assays remain insufficiently characterized. A choline chloride-urea-water DES (1:2:4) was compared with 70% ethanol for extracting polyphenols from onion bulbs and peels from cultivars grown in Spain and North Macedonia. Extraction conditions were selected through a comparative evaluation of vortex- and ultrasound-assisted extraction and benchmarked against conventional ethanolic stirring (2 h). Two-way ANOVA identified solvent composition as the main determinant of total phenolic content (F(1,20) = 1526.28, p < 0.001), while extraction method significantly influenced recovery under DES conditions (F(2,30) = 408.52, p < 0.001). The selected UAE-DES protocol increased TPC up to 2.2-fold and reduced extraction time to <5 min. TPC ranged from 25 to 44 mg GAE/g dw in bulbs and 42–62 mg GAE/g dw in peels, with red cultivars showing the highest values. UHPLC-MS/MS revealed solvent-dependent selectivity: ethanol favored flavonols (quercetin 5–11 mg/g dw), whereas DES enhanced phenolic acids (gallic acid up to 0.3 mg/g dw; protocatechuic acid up to 7 mg/g dw). FRAP correlated with TPC (r = 0.64–0.92), while ABTS was incompatible with DES extracts. Storage reduced TPC by 45–75% but preserved cultivar ranking. These findings demonstrate that UAE-DES enables rapid and efficient polyphenol recovery while highlighting the need to validate antioxidant assays in non-conventional solvents. Full article

The laminin-derived nonapeptide CDPGYIGSR contains the bioactive YIGSR motif, historically associated with inhibition of tumor cell adhesion, invasion, angiogenesis, and laminin-receptor-mediated cell responses. Although these activities have often been attributed to the 37/67 kDa laminin receptor/RPSA axis, the molecular identity and organization of the laminin-binding receptor system remain debated. This uncertainty makes it essential to define the intrinsic conformational preferences of CDPGYIGSR in solution before assigning a unique receptor-bound structure. In this study, temperature replica-exchange molecular dynamics (T-REMD) simulations in explicit solvent are employed to characterize the solution conformational ensemble of CDPGYIGSR. Free energy landscape analysis, clustering, and structural descriptors reveal a predominant compact bend-like backbone arrangement, together with alternative low-lying conformational states within a heterogeneous ensemble. Rather than assuming a single bioactive conformation, the conformational ensemble is analyzed in terms of structural features that are consistent with available NMR observations and reported structure–activity relationships. Importantly, the most populated conformations in solution do not necessarily correspond to the bioactive state upon receptor binding. Instead, a subset of conformations sharing common structural motifs, including a central backbone bend and specific residue exposure patterns, may represent states compatible with receptor recognition. These results provide an ensemble-based structural framework that connects simulation-derived conformational motifs with available NMR observations and structure–activity data, supporting a recognition-compatible ensemble model in which compact preorganized states may contribute to receptor binding. Full article

Interzeolite transformation (IZT) has emerged as a versatile strategy for accessing zeolite frameworks through controlled framework reorganization under comparatively simplified synthesis conditions. Unlike traditional synthesis approaches that frequently require organic structure-directing agents (OSDAs), highly alkaline media, and prolonged thermal treatment, IZT converts pre-existing zeolite into a new topology, enabling direct reuse of crystalline matter while reducing synthesis complexity. This review examines how structural drivers, including framework density, structural memory, and building-unit compatibility, govern transformation pathways and phase selectivity across five principal transformation approaches: (i) solution-mediated, (ii) assembly–disassembly–organization–reassembly (ADOR), (iii) mechanically assisted, (iv) steam-assisted, and (v) fully solid-state systems. These approaches promote distinct transformation pathways that govern framework reconstruction, structural inheritance, and phase selectivity. Recent advances in solvent-free, mechanochemical, steam-assisted, and microwave-assisted synthesis demonstrate the potential of IZT to reduce solvent consumption, template usage, and crystallization times. Despite these advances, major challenges remain in predicting transformation outcomes, controlling transient intermediates, and establishing scalable and quantitatively validated sustainability metrics. Collectively, these developments position IZT as a promising platform for the rational and sustainable design of next-generation zeolitic materials. Full article

Growing demand for greener and more sustainable materials in cultural heritage conservation has prompted the investigation of bio-based alternatives for cleaning applications. This study presents a preliminary evaluation of bacterial nanocellulose (BNC) membranes for the removal of acrylic resins from mural paintings, comparing commercial medical-grade and laboratory-produced BNC with conventional gel systems under simulated application conditions. Both BNC types were characterized in terms of composition, pH, electrical conductivity, Water Holding Capacity and Water Retention Rate. Acetone loading via solvent exchange was assessed by thermogravimetric analysis (TGA), while mechanical behavior before and after solvent loading was evaluated through tensile testing and optical density measurements of the immersion media. The performance of BNCs and reference delivery systems was comparatively assessed in terms of solvent retention, solvent penetration depth into the substrate and residue release. Cleaning performance was investigated through FTIR spectroscopy and semi-quantitative image analysis as indirect indicators of residual resin content, on both mock-up samples and in situ applications. Under the tested conditions, both BNC membranes were compatible with acetone loading and maintained mechanical integrity after solvent exposure. FTIR analysis showed a reduction in the acrylic carbonyl band after treatment with acetone-loaded BNC, which exhibited greater solvent diffusion depth; the underlying removal mechanism, including the possible contribution of solvent-driven redistribution phenomena, remains to be clarified. Differences in reproducibility were observed between medical-grade and laboratory-produced BNC. Overall, the study provides experimental data contributing to the assessment of BNC membranes as bio-based solvent delivery systems for conservation practice. Full article

Background: 5-(3′,4′-Dihydroxyphenyl)-γ-valerolactone (DHPV) is a postbiotic gut microbiota-derived flavanol metabolite with reported anti-inflammatory activity. Despite growing interest in its potential dermatological applications, its pharmaceutical properties and suitability for topical delivery have not been systematically investigated. This study aimed to perform the first comprehensive preformulation and formulation-oriented evaluation of DHPV and to develop stable topical ointment formulations suitable for further dermatological research. Methods: The physicochemical properties of DHPV were characterized using powder X-ray diffraction (PXRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), quantitative solubility assessment, and excipient compatibility studies. Based on the obtained preformulation data, two anhydrous ointment formulations containing DHPV were developed. The formulations were evaluated for homogeneity, rheological behavior, chemical stability under accelerated storage conditions, and in vitro drug release performance. Results: DHPV was identified as a crystalline compound with heterogeneous particle morphology and limited aqueous solubility. Quantitative solubility studies demonstrated the highest solubility in PEG 300 and glycol-based solvents. Compatibility testing revealed increased impurity formation in hydrophilic environments, whereas lipophilic excipients provided improved chemical stability. Both ointment formulations exhibited acceptable physical characteristics and maintained DHPV stability throughout accelerated storage. However, marked differences in release behavior were observed. The lipid–wax formulation showed significantly higher release rates, lower variability, and more reproducible release profiles than the petrolatum-based reference formulation, indicating more efficient diffusion of DHPV from the semisolid matrix. Conclusions: The physicochemical characteristics of DHPV strongly influence formulation design and performance. Anhydrous lipid-based systems provide a favorable environment for maintaining DHPV stability, while formulation composition significantly affects drug release. The developed lipid–wax formulation represents a promising platform for future skin permeation, pharmacodynamic, and efficacy studies. Full article

Background/Objectives: Oral candidiasis is an infection of the oral cavity caused by Candida albicans. Mucoadhesive buccal films could adhere to the buccal mucosa for prolonged periods, improving the therapeutic outcomes of patients with oral candidiasis. This study aimed to develop and evaluate the properties of fluconazole containing sodium alginate/methylcellulose-based buccal films for potential treatment of oral candidiasis. Methods: Drug-polymer compatibility was investigated using FT-IR spectrophotometry. Three optimised fluconazole films (F1 to F3) containing 1–1.6% sodium alginate and methylcellulose (1.6%) were formulated using the solvent-casting method. Their physicomechanical properties were characterised using standard protocols. Drug content and in vitro drug release profiles were evaluated using UV-visible spectroscopy; in vitro/ex vivo mucoadhesion studies were conducted using the shaking water bath technique, and their antifungal activity against Candida albicans was evaluated using the agar ditch method. Results: FT-IR data analysis revealed that sodium alginate, methylcellulose and fluconazole were compatible in the films. The films were off-white, smooth, peelable, thin, with satisfactory pH values, folding endurance, drug content, excellent zones of inhibition against Candida albicans (40 mm), controlled drug release profile (3.6–4.1 mg/cm² after 6 h), and they displayed Korsmeyer–Peppas drug release kinetics. Film F3 containing 1.6% sodium alginate and 1.6% of methylcellulose exhibited superior swelling index (70 ± 1%), tensile strength (0.68 ± 0.04 MPa) and in vitro/ex vivo mucoadhesion time (5.5 ± 0.3 h; 2.3 ± 0.3 h) relative to other studied films. Conclusions: The sodium alginate content of the films influenced their tensile and mucoadhesive properties. Film F3 was the most promising formulation for potential treatment of oral candidiasis. Full article

Background: Fresh frozen tissues are considered the gold standard for proteomic analyses due to their superior preservation of protein integrity; however, their use is limited by the logistical and financial requirements of long-term cold storage. Formaldehyde-fixed paraffin-embedded (FFPE) tissues provide a practical alternative, owing to their stability and widespread availability in clinical settings. A critical step in FFPE proteomics is deparaffinization, which traditionally relies on organic solvents such as xylene, along with the efficient reversal of formaldehyde-induced crosslinks. Methods: In this study, we evaluated multiple FFPE protein extraction and digestion workflows including chaotropic, surfactant-based, and detergent-free approaches in combination with xylene-free deparaffinization strategies, using label-free data-independent acquisition (DIA) LC-MS/MS. Results: Among the tested methods, a chaotropic, reductant, and surfactant-free in-solution digestion workflow demonstrated robust protein and peptide recovery. A modified version of this protocol further improved peptide coverage while maintaining comparable protein depth. The applicability of the optimized workflow was assessed using FFPE needle biopsy samples from control, hepatic steatosis, and liver fibrosis groups. Exploratory proteomic patterns were observed across conditions, with hepatic steatosis associated with early activation of stress-response pathways, while fibrosis showed evidence suggesting altered lipid metabolism. Conclusions: Overall, this study presents a simple, xylene-free, and MS-compatible workflow for FFPE proteomics that is suitable for low-input clinical samples and may support broader application of archival tissues in proteomic research. Full article

Quinoline derivatives constitute a privileged class of nitrogen-containing heterocycles with extensive applications in medicinal chemistry, agrochemicals, materials science, and functional organic materials. Owing to their broad biological and industrial relevance, the development of efficient, selective, and sustainable synthetic methodologies for quinoline construction remains an active area of research. This review provides a comprehensive overview of recent advances in quinoline synthesis, with particular emphasis on catalytic strategies aligned with the principles of green and sustainable chemistry. Classical transformations, including the Friedländer, Skraup, and Povarov reactions, are revisited in the context of modern catalytic developments that improve reaction efficiency, substrate scope, selectivity, and environmental compatibility. Special attention is devoted to homogeneous and heterogeneous catalytic systems based on both platinum-group and earth-abundant transition metals, highlighting the growing importance of borrowing-hydrogen and acceptorless dehydrogenative coupling methodologies. Recent progress in nanocatalysis, photocatalysis, multicomponent reactions, ionic-liquid-mediated transformations, and metal-free protocols is also critically discussed. Furthermore, solvent-free processes, microwave-assisted synthesis, and recyclable catalytic systems are examined as practical approaches toward minimizing waste generation and energy consumption. Mechanistic aspects, catalytic design principles, substrate limitations, and sustainability metrics are evaluated throughout the review to provide a critical perspective on current methodologies. Collectively, the advances summarized herein demonstrate the rapid evolution of quinoline synthesis toward more atom-economical, environmentally benign, and operationally efficient processes, while also identifying future opportunities for the development of next-generation catalytic platforms for quinoline-based heterocycle construction. Full article

Per- and polyfluoroalkyl substances (PFASs) constitute a chemically diverse family of persistent contaminants, the regulation of which is tightening rapidly in Europe and the United States. Granular activated carbon, selective ion exchange, and pressure-driven membranes remove many long-chain PFASs, but their performance is less robust for short-chain and ultrashort species, and all generate concentrated secondary waste streams. Hydrophobic deep eutectic solvents (DESs), including natural deep eutectic solvents (NADESs), have emerged as tunable liquid extractants able to concentrate PFASs into small solvent volumes that can be regenerated or coupled to destruction. This perspective differs from existing DES-PFAS reviews by converting qualitative solvent-selection arguments into a decision framework with explicit acceptance gates: broad PFAS affinity, a component-resolved non-migration specification for treated water, viscosity and mass-transfer limits, regenerability targets, and techno-economic/life-cycle benchmarking against incumbent processes. We refine the bifunctional DES design hypothesis by separating validated regimes from unresolved cases, identifying the reliability limits of COSMO-RS, molecular dynamics, and machine-learning screening, and defining tiered reporting requirements for early-stage studies. The central message is that PFAS-extracting DES should no longer be evaluated only by single-compound removal percentages; they must be judged as integrated, closed-loop treatment materials with solvent losses, regeneration stability, destruction compatibility, cost, and environmental impacts that are quantified from the outset. Full article

Thermoplastic starch (TPS) and polyvinyl alcohol (PVA) blends were prepared over the full compositional range (0–100 wt% PVA) by solvent-free twin-screw extrusion and injection molding. This enabled a systematic evaluation of structure–performance–disintegration relationships under industrially relevant conditions. The blends exhibited clear composition-dependent trends in thermal and mechanical behavior. Increasing PVA content from 0 to 100 wt% raised the onset degradation temperature (T5%) from 160.5 °C to 290.5 °C and increased crystallinity from near zero to 12.24%. Mechanically, the response evolved from a rigid TPS-rich state to a ductile PVA-rich one. FTIR and SEM analyses indicated partial compatibility, with limited molecular-level interactions leading to morphologically homogeneous but only partially miscible blends. Under simulated composting conditions, all formulations showed substantial physical disintegration. PVA-rich blends (≥60 wt%) disintegrated rapidly (>80% mass loss within two days), primarily by dissolution rather than microbial degradation. Overall, this work provides a comprehensive, scalable assessment of solvent-free TPS/PVA blends, clarifies their limited compatibility under melt processing, and demonstrates how composition can be used to tailor structure, performance, and disintegration behavior across the full compositional range. Full article

In this study, a novel magnetic metal–organic framework (MOF) composite, Pd@UiO-66@Fe₃O₄, was successfully synthesized as a high-performance heterogeneous catalyst for the Suzuki–Miyaura cross-coupling reaction. The material was prepared by loading nano-sized carboxylated Fe₃O₄ onto UiO-66 via an in situ solvothermal method, followed by the encapsulation of Pd nanoparticles using an ultrasound-assisted dual-solvent method (DSA). Characterization results, including PXRD and TEM, confirmed that the ternary composite retains the structural integrity of UiO-66 while incorporating magnetic functionality and well-dispersed Pd active sites. The catalyst exhibited high catalytic performance for the coupling of aryl iodides and aryl boronic acids. Furthermore, the catalyst demonstrated good compatibility with the substrates examined and excellent stability. Due to the integration of carboxylated Fe₃O₄, the composite could be easily separated from the reaction mixture using an external magnet and reused for at least five cycles without a significant loss in catalytic activity. The high activity and durability are attributed to the integrated roles of the Pd nanoparticles, the porous MOF support, and the magnetic Fe₃O₄ component, which respectively provide catalytic active sites, structural stabilization/dispersion, and magnetic recoverability. Full article

Medicinal plants represent a promising source of bioactive compounds with potential antidiabetic activity, while the efficacy of plant extracts depends on both plant matrix and extraction conditions. This study aimed to systematically compare selected medicinal plants and extraction solvents to evaluate their impact on extracts’ in vitro α-amylase inhibitory activity, total polyphenol content (TPC), antioxidant capacity, and antimicrobial properties. Extracts of sage (Salvia officinalis), blueberry leaf (Vaccinium myrtillus), nettle (Urtica dioica), wormwood (Artemisia absinthium), and green and roasted coffee (Coffea arabica) were prepared using different solvent systems (50% (v/v) ethanol, propylene glycol, glycerol, and water), as well as a traditional aqueous infusion protocol. Extraction solvent strongly affected bioactivity: ethanol extracts showed the highest α-amylase inhibition, particularly in sage extract (79.60%) and blueberry leaf (57.71%). No significant correlation with TPC was observed (r = 0.229, p = 0.108), but aqueous ethanol yielded the highest TPC, with blueberry leaf being richest (64.16 ± 0.82 mg GAE/g), followed by roasted coffee (49.36 ± 0.83 mg GAE/g). Ethanol extracts demonstrated antibacterial activity against Staphylococcus aureus. Overall, sage and blueberry leaves showed the most promising multifunctional activity, highlighting their potential for further investigation as functional food ingredients. Full article

Increasing regulatory demands for high-quality plastic recycling create a strong need for novel tracer systems that enable reliable polymer identification and sorting. This feasibility study evaluates germanium nanocrystals (GeNCs) as Raman-detectable tracer materials in polypropylene (PP). The synthesis of GeNC/PP composite materials possessing various GeNC contents via a solvent-based intercalation process followed by compounding and injection molding is reported. Hydride-terminated GeNCs were synthesized and subsequently functionalized with dodecyl ligands to ensure chemical stability, compatibility with the polymer matrix, and processability under conventional melt-processing conditions. The dodecyl-functionalized GeNCs were successfully stabilized and homogeneously integrated into the PP matrix. Raman spectroscopy demonstrates the clear detection of GeNCs within the composites through a characteristic Ge–Ge optical phonon mode at 296 cm⁻¹, which is well separated from the intrinsic Raman bands of polypropylene. The Raman signal intensity increases systematically with increasing GeNC concentration. Raman mapping reveals an overall homogeneous distribution of the nanocrystals within the polymer, while a slight tendency toward agglomeration is observed at higher loadings. These results demonstrate that GeNCs are well suited as optically detectable tracers for polypropylene and can be reliably identified using Raman spectroscopy, highlighting their potential for tracer-based sorting concepts in advanced recycling and digital material passport applications. Full article

Grape pomace, the main solid by-product of winemaking, is a promising feedstock for the recovery of trans-resveratrol, a high-value stilbene of increasing interest for food, nutraceutical, and pharmaceutical applications. However, its efficient isolation remains challenging because of matrix complexity, the co-occurrence of structurally related stilbenes and polyphenols, and the chemical instability of trans-resveratrol. This review critically examines recent advances in the recovery of trans-resveratrol from grape pomace, while also incorporating relevant findings from other grapevine-derived matrices to distinguish matrix-specific recovery potential and to place grape pomace within the broader context of grapevine by-product valorization from extraction intensification and selective purification to analytical determination. Various extraction technologies, including ultrasound-, microwave-, and enzyme-assisted extraction, natural deep eutectic solvents, and subcritical water extraction, are assessed alongside conventional solvent extraction with emphasis on yield, selectivity, solvent compatibility, and process feasibility. Downstream separation methods such as liquid–liquid partitioning, solid-phase isolation, adsorbent resins, counter-current chromatography, molecularly imprinted polymers, and foam fractionation are compared in terms of selectivity, enrichment efficiency, solvent demand, and scale-up potential. Although significant progress has been achieved, major challenges remain regarding process integration, solvent sustainability, product stability, and industrial feasibility. Combining mild extraction with selective downstream purification is essential for producing stable, high-purity trans-resveratrol fractions suitable for future use in functional ingredients, natural preservation strategies, and other value-added applications within sustainable food systems. Full article

The increasing global demand for natural bioactive compounds in the food, nutraceutical, and pharmaceutical sectors highlights the need for sustainable extraction technologies capable not only of efficiently valorizing crop biomass and agro-waste but also of producing reproducible and standardized botanical extracts. Subcritical water extraction (SWE), which utilizes pressurized hot water at temperatures between 100 °C and 374 °C to modify solvent properties, has emerged as a promising green alternative to conventional organic solvent-based extraction methods. Despite its advantages in terms of environmental compatibility, extraction efficiency and tunable selectivity, the industrial application of SWE remains limited, and strategies for obtaining standardized extracts using this technology are still insufficiently explored. This review provides a comprehensive overview of SWE in the context of natural product extraction and the development of standardized plant extracts. The fundamental principles of SWE are discussed, including temperature-dependent changes in water polarity, solvent–solute interactions, and the influence of key process parameters such as temperature, pressure, extraction time, and particle size. Particular emphasis is placed on how these factors affect extraction selectivity, phytochemical composition, and reproducibility, which are critical aspects for extract standardization. Mechanistic insights into plant cell disruption, compound stability, and hydrothermal transformations under SWE conditions are also examined. Recent applications of SWE for the extraction of phenolics, flavonoids, terpenoids, alkaloids, and other pharmacologically relevant compounds are reviewed, highlighting the relationship between extraction conditions and extract quality. Finally, current challenges and future perspectives for integrating SWE into the production of standardized botanical extracts suitable for food, nutraceutical, and pharmaceutical applications are discussed, paving the way for the wider industrial adoption of this environmentally friendly technology. Full article