Search Results (338)

The competitive retention of pollutants in water tables determines their environmental fate and guides routes for their removal. To distinguish the fine differences in competitive binding at zeolite adsorption centers, a group of neonicotinoid pesticides is compared, relying on theoretical (energy of adsorption, orientation, charge distribution) and experimental (spectroscopic and thermogravimetric) analyses for quick, inexpensive, and reliable screening. The MOPAC/QuantumEspresso platform was used for theoretical calculation, indicating close adsorption energy values for acetamiprid and imidacloprid (−2.2 eV), with thiamethoxam having a lower binding energy of −1.7 eV. FTIR analysis confirmed hydrogen bonding, among different dipole-dipole interactions, as the dominant adsorption mechanism. Due to their comparable binding energies, when the mixture of all three pesticides is examined, comparative adsorption capacities are evident at low concentrations, owing to the excellent adsorption performance of the FAU zeotype. At higher concentrations, competition for adsorption centers occurs, with the expected thiamethoxam binding being diminished due to the lower bonding energy. The catalytic impact of zeolite on the thermal degradation of pesticides is evidenced through TG analysis, confirming the adsorption capacities found by UV/VIS and HPLC/UV measurements. Detailed analysis of spectroscopic results in conjunction with theoretical calculation, thermal profiles, and UV detection offers a comprehensive understanding of neonicotinoids’ adsorption and can help with the design of future adsorbents. Full article

In this work, we report a novel mechanochemical synthesis method for the synthesis of quinoxaline derivatives—a spiral gas–solid two-phase flow approach, which enables the efficient preparation of quinoxaline compounds. Compared to conventional synthetic methods, this approach eliminates the need for heating or solvents while significantly reducing reaction time. The structures of the synthesized compounds were characterized using nuclear magnetic resonance (NMR), Fourier-transform infrared spectroscopy (FT-IR), ultraviolet-visible (UV–Vis) absorption spectroscopy, powder X-ray diffraction (XRD), differential scanning calorimetry (DSC), and high-performance liquid chromatography (HPLC). Using the synthesis of 2,3-diphenylquinoxaline (1) as a model reaction, the synthetic process was investigated with UV–Vis spectroscopy. The results demonstrate that when the total feed amount was 2 g with a carrier gas pressure of 0.8 MPa, the reaction completed within 2 min, achieving a yield of 93%. Furthermore, kinetic analysis of the reaction mechanism was performed by monitoring the UV–Vis spectra of the products at different time intervals. The results indicate that the synthesis of 1 follows the A4 kinetic model, which describes a two-dimensional diffusion-controlled product growth process following decelerated nucleation. Full article

Background/Objectives: The emergence of antimicrobial resistance represents a critical global health threat, requiring the discovery of novel bioactive compounds. Fungi from Amazonian biodiversity are promising sources of secondary metabolites with potential antimicrobial activity. This study aimed to investigate the production of antimicrobial compounds by two Amazonian fungal strains using the OSMAC (One Strain–Many Compounds) approach. Methods: Two fungal strains, Talaromyces pinophilus CCM-UEA-F0414 and Penicillium paxilli CCM-UEA-F0591, were cultivated under five distinct culture media to modulate secondary metabolite production. Ethyl acetate extracts were prepared and evaluated for antimicrobial activity against Gram-positive and Gram-negative bacteria, as well as pathogenic yeasts. Chemical characterization was performed using thin-layer chromatography (TLC), Fourier Transform Infrared Spectroscopy (FTIR), Ultraviolet–Visible (UV-Vis) spectroscopy, and Ultra-High-Performance Liquid Chromatography with Diode Array Detection (uHPLC-DAD). Results: The extracts exhibited significant antimicrobial activity, with minimum inhibitory concentrations (MICs) ranging from 78 to 5000 µg/mL. Chemical analyses revealed the presence of phenolic compounds, particularly caffeic and chlorogenic acids. Variations in the culture media substantially affected both the metabolite profiles and antimicrobial efficacy of the extracts. Conclusions: The OSMAC strategy effectively enhanced the metabolic diversity of the Amazonian fungal strains, leading to the production of bioactive metabolites with antimicrobial potential. These findings support the importance of optimizing culture conditions to unlock the biosynthetic capacity of Amazonian fungi as promising sources of antimicrobial agents. Full article

Sideroxylon cinereum, an endemic Mauritian fruit, was investigated through comprehensive chemical analyses of solvent extracts from its pulp and seed. Dried fruit materials were subjected to maceration using water and organic solvents including methanol, ethanol, propanol, and acetone to obtain extracts of varying polarity. Preliminary phytochemical screening revealed the presence of several bioactive compounds, with pulp extracts generally richer in phytochemicals than seed extracts. UV-Vis and FTIR analyses confirmed key organic constituents, including sulfoxides in seeds. HPLC quantification showed notable citric acid content in the pulp (15.63 mg/g dry weight). Antioxidant assays indicated that organic solvent extracts of the pulp had superior free radical scavenging activity, while the seed’s aqueous extract exhibited the highest ferric reducing power. GC–MS profiling identified a diverse bioactive profile rich in terpenes, notably lanosterol acetate (>45% in both pulp and seeds). It is important to note that these findings are based on solvent extracts, which may differ from the phytochemical composition of the whole fruit as typically consumed. Among the extracts, aqueous fractions are likely the most relevant to dietary intake. Overall, the extracts of Sideroxylon cinereum pulp and seed show potential as sources of bioactive compounds for functional product development. Full article

Background/Objective: Programmed cell death ligand-1 (PD-L1), which is overexpressed in certain tumors, inhibits the body’s natural immune response by providing an “off” signal that enables cancer cells to evade the immune system. It has been demonstrated that [¹⁷⁷Lu]Lu-DOTA-iPD-L1 (PD-L1 inhibitor cyclic peptide) promotes immune responses. This study aimed to synthesize and evaluate [¹⁸F]AlF-NOTA-iPD-L1 as a novel radiotracer for PD-L1 positron emission tomography (PET) imaging and as a potential theranostic pair for [¹⁷⁷Lu]Lu-DOTA-iPD-L1. Methods: The NOTA-iPD-L1 peptide conjugate was synthesized and characterized by U.V.-vis, I.R.-FT, and UPLC-mass spectroscopies. Radiolabeling was performed using [¹⁸F]AlF as the precursor, and the radiochemical purity (HPLC), partition coefficient, and serum stability were assessed. Cellular uptake and internalization (in 4T1 triple-negative breast cancer cells), binding competition, immunofluorescence, and Western blot assays were applied for the radiotracer in vitro characterization. Biodistribution in mice bearing 4T1 tumors was performed, and molecular imaging (Cerenkov images) of [¹⁸F]AlF-NOTA-iPD-L1 and [¹⁷⁷Lu]Lu-DOTA-iPD-L1 in the same mouse was obtained. Results: [¹⁸F]AlF-NOTA-iPD-L1 was prepared with a radiochemical purity greater than 97%, and it demonstrated high in vitro and in vivo stability, as well as specific recognition by the PD-L1 protein (IC₅₀ = 9.27 ± 2.69 nM). Biodistribution studies indicated a tumor uptake of 6.4% ± 0.9% ID/g at 1-hour post-administration, and Cerenkov images showed a high tumor uptake of both [¹⁸F]AlF-NOTA-iPD-L1 and ¹⁷⁷Lu-iPD-L1 in the same mouse. Conclusions: These results warrant further studies to evaluate the clinical usefulness of [¹⁸F]AlF-NOTA-iPD-L1/[¹⁷⁷Lu]Lu-DOTA-iPD-L1 as a radiotheranostic pair in combination with anti-PD-L1/PD1 immunotherapy. Full article

Retinoids are used in cosmetics as anti-aging ingredients, along with other substances. However, due to limitations in use (such as photodegradation), it seems necessary to look for retinoid alternatives to be applied in cosmetic products. Bakuchiol, a natural alternative of retinoids, isolated from Psolarea corylifolia, is one such compound. It has great cosmetic potential and its mechanism of action is not yet fully explored. From the point of view of the bioactive compound, it is also essential to develop a method for rapid quality control of cosmetic preparations containing bakuchiol. The aim of this study was to apply and compare methods for the quantification of bakuchiol in cosmetic products using UV-Vis, ¹H qNMR, and HPLC. The results show the possibility of using the ¹H NMR method in the routine quality control of cosmetics with bakuchiol because of its comparable results with HPLC analysis and significantly shorter analysis time. Full article

The development of reversible animal models for the study of intestinal pathologies is essential to reduce the number of animals used in research and to better understand disease mechanisms. In this study, we present a reversible model of intestinal malabsorption through the administration of sublethal doses of ebulin-f, a ribosome-inactivating protein, and validate its usefulness by monitoring vitamin C absorption. The scientific community increasingly recognizes the importance of rationalizing experimental designs, optimizing treatment protocols, and minimizing the use of animals in research models. Thus, new methodologies are needed to minimize invasive sampling and to develop reversible animal models that recover physiologically post-study. Such models are essential for in vivo studies of human pathologies. Sublethal doses of ebulin-f (2.5 mg/kg) administered intraperitoneally to female Swiss CD1 mice (n = 6 per group) can cause reversible intestinal alterations in the small intestine, which offer the possibility of having a valuable reversible study model of malabsorption for the investigation of this syndrome. To verify whether nutrient absorption is altered, we used vitamin C as a traceable nutrient that can be quantified in the blood. Peripheral blood samples were collected through the retro-orbital area at 30, 80, 120, 180, and 1440 min post-administration, treated with DTT and MPA, and analyzed using a validated UV/Vis–HPLC method to indirectly determine vitamin C absorption by enterocytes. Pharmacokinetic analysis revealed significantly increased vitamin C absorption on days 1 and 3 post-treatment (AUC values of 3.65 × 10⁴ and 7.10 × 10⁴, respectively) compared to control (0.94 × 10⁴), with partial recovery by day 22 (3.27 × 10⁴). Blood concentration profiles indicate that intestinal damage peaks at day 3, followed by significant regeneration by day 22, establishing this as a viable reversible model for inflammatory bowel disease research. Full article

Nejayote (Nej), an effluent from nixtamalization process, has an alkaline pH and contains a high load of organic matter in suspension and dissolution, which makes it a highly polluting waste when discharged directly into the environment. However, the sustainable reuse of this effluent is relevant since it contains high-value compounds (ferulic acid (FA)) with appropriate activity for the ecological synthesis of silver nanoparticles (AgNPs). This study explores the synthesis of AgNPs using Nej as a reducing and stabilizing agent and evaluates the antibacterial effectiveness of AgNPs against Escherichia coli (E. coli). The AgNPs under study possess excellent optical (UV-Vis) and structural properties (XRD). HR-TEM images show predominantly spherical particles, with an average size of 20 nm. FTIR spectroscopy identified functional groups, including phenols and flavonoids, on the nanoparticle surface, acting as stabilizing agents. HPLC supports the existence of FA in the AgNPs. Biogenic AgNPs exhibit enhanced antibacterial activity due to the adsorption of these functional groups onto their surface, which contributes to bacterial membrane disruption. Finally, no hemolytic or cytotoxic activity was observed, suggesting that the AgNPs exert antimicrobial activity without potentially harmful doses (biocompatibility). The study highlights the potential of Nej as a sustainable source for use in nanoparticle synthesis, promoting the recycling of agro-industrial waste and the production of materials with technological applications. Full article

Peroxymonosulfate (PMS)-based advanced oxidation technology has emerged as an effective means for removing organic pollutants from water due to its strong oxidizing ability. However, enhancing the activation efficiency of PMS represents a key challenge at present. SrTiO₃, a typical perovskite metal oxide, holds potential in the field of the photocatalytic degradation of pollutants, yet its application is limited by the wide bandgap and fast carrier recombination rates. This study optimized the photocatalytic performance of SrTiO₃ by regulating its electronic structure and optical properties through cobalt (Co) doping. Experimental results (TRPL, TPV, UV–Vis DRS, ESR, etc.) and DFT calculations (GGA-PBE) demonstrated that Co doping shifted the d-band center of SrTiO₃ upwards, optimized the adsorption energy of SO₄⁻, enhanced the sunlight response range, and significantly improved carrier extraction efficiency. Under visible light irradiation, 2,4-dichlorophenol (2,4-DCP) could be effectively degraded within 60 min in a wide pH range. Through Fukui function calculation (B3LYP/6-31G*) and experimental characterization analysis (HPLC-MS and IC), the possible degradation pathways of 2,4-DCP and the mechanism for photocatalysis were investigated. The toxicity analysis (T.E.S.T) confirmed the reduced toxicity of the degradation products of 2,4-DCPs. This study provides a reference for the catalyst design and optimization strategy of PMS-based advanced oxidation technology. Full article

In this study, a boron-doped diamond (BDD) sensor was used to study the electroanalytical behavior of emerging contaminants (ECs), such as caffeine, paracetamol and methyl orange. BDD shows strong resolving power for the superimposed voltammetric response of ECs in well-resolved peaks with increased peak current. Differential pulse voltammetry, which is an electroanalytical technique, was compared with two reference techniques including absorption spectrophotometry in the UV-vis region and high-performance liquid chromatography (HPLC) in the detection and quantification of ECs. The results obtained were satisfactory, as the complete removal of ECs was achieved in all applied processes. The detection limits were 0.69 mg L⁻¹, 0.84 mg L⁻¹ and 0.46 mg L⁻¹ for CAF, PAR and MO, respectively. The comparison of electroanalysis results with those obtained by UV-vis and HPLC established and confirmed the potential applicability of the technique for determining CAF, PAR and MO analytes in synthetic effluents and environmental water samples (tap water, groundwater and lagoon water). The electrochemical approach can therefore be highlighted for its low consumption of reagents, ease of operation, time of analysis and excellent precision and accuracy, because these are characteristics that enable the use of this technique as another means of determining analytes in effluents. Full article

Tagetes erecta L. is an ornamental crop known for its medicinal qualities. Large amounts of waste are produced in the commercial usage of T. erecta flowers, including leaves that could be used to develop new eco-friendly phenolic extracts with additional value for the food industry. To maximize the phenol content in the leaf extracts, this study used a Box–Behnken design with Response Surface Methodology, considering three extraction methods (Soxhlet distillation, heat, and vacuum-assisted extraction), three cropping practices (without fertilizer, chemical fertilizer, and vermicompost), and three phenological stages (plants without buds, with buds, and in flower). Extracts from plants fertilized with vermicompost (Eisenia foetida, 10 t ha⁻¹), collected during the blossoming stage and extracted via Soxhlet distillation, exhibited the highest phenol content (25.66 mg GAE/g). Further chemical characterization of the optimized extract (UV-Vis, UV-fluorescence, FTIR, GC-MS, HPLC) confirmed the occurrence of polyphenols in the extract, including quercetin, chlorogenic, gallic, p-coumaric, 3-hydroxycinnamic, and caffeic acids. This underscores the significance of T. erecta leaf residues as a valuable source of bioactive molecules, highlighting the importance of integrating agricultural practices and chemical extraction methods to enhance the phenolic content in leaf extracts from this species. Full article

In 1842, carpet manufacturer W.H. Worth of Kidderminster, England, began assembling a sample book of wool yarns dyed with natural dyestuffs. This paper reports on a study of the “Greens” section, which contains sixteen yarn samples—six still green and ten now ranging from tan to dark brown. The accompanying recipes list similar ingredients: old fustic and either “mixture” or extracet of indigo. To verify whether Worth’s recipes were followed, the yarns were analyzed using HPLC-DAD and FORS. Additionally, mock-ups were prepared according to Worth’s green dye recipes and subjected to thermal ageing to explore potential causes of discoloration. Preliminary analysis of the historic samples revealed that the discoloured yarns contain both indigo and indigo carmine, while the still-green samples contain only indigo carmine. This suggests that one or more components of the indigo vat may have contributed to discoloration. To test this hypothesis, contemporary wool yarns were dyed using a Worth green recipe, with and without indigo, at varying pH levels. These were thermally aged, and their colour changes monitored. HPLC-DAD and FORS analyses of the mock-ups were compared to the historic samples to identify dyeing conditions that may have led to the observed browning. Full article

The Fabaceae family is known for the presence of isoflavones—phytoestrogens with potential chemopreventive effects against hormone-dependent cancers. This study aimed to optimize isoflavones extraction using a fractional factorial design and to quantitatively and qualitatively analyze 32 Fabaceae species native to Polish flora by HPLC-UV-VIS to indicate new, rich plant sources of isoflavones. The optimal extraction method was a 60 min reflux with 50% methanol and a plant material-to-solvent ratio of 1:125. The highest isoflavone levels were found in Trifolium medium (26.70 mg/g d.m.), Genista tinctoria (19.65 mg/g d.m.), and Trifolium pratense (12.56 mg/g d.m.). The obtained extracts were further evaluated for cytotoxic and antiproliferative activity against MCF7 and MDA-MB-231 human breast cancer cells. Genista tinctoria showed the highest cytotoxicity against MCF7, while Cytisus scoparius and Ononis arvensis were most effective against MDA-MB-231 at a dose of 500 µg/mL. The extracts were also characterized by varied, potent antioxidant properties, important in chemoprevention. A strong correlation was observed between isoflavone content and cytotoxic and antiproliferative activity exclusively in the estrogen receptor-positive MCF7 cell line. Importantly, the tested extracts demonstrated no toxic effects on normal human liver (HepG2), thyroid (Nthy-ori 3-1), or breast (MCF10A) cells, indicating a favorable safety profile. Full article

Wine is a popular beverage worldwide, and its consumption continues to rise, leading to waste, particularly from vine prunings and grape pomace. The aim of this study was to create a valorization pathway utilizing these waste materials. To achieve this, proximate analysis, chemical composition, ultimate analysis, thermogravimetric analysis (TGA), and other physicochemical parameters for both vine prunings and grape pomace were assessed. Based on the results, vine prunings were identified as suitable for direct combustion in energy applications, and grape pomace was found to be suitable as an antioxidant in vegetable oil. Grape pomace extract showed the following results through UV-vis spectroscopy: total phenolic content of 1688.10 mg GAE/100 g, total flavonoids of 1330.39 mg catechin/100 g, and total anthocyanins of 12.61 mg cyanidin-3-glucoside/100 mg. The antioxidant capacity was measured through various assays: FRAP yielded 2179.19 mg ascorbic acid/100 g; DPPH measured 1704.41 µmol Trolox/100 g; and ABTS showed 48,271.31 µmol Trolox/100 g. The ORAC results, as determined by fluorescence spectroscopy, were 53,694.93 µmol Trolox/100 g. HPLC profiling revealed cyanidin as the main anthocyanin (26.52 mg/L) and epicatechin as the most abundant flavonoid (214.29 mg/L). Finally, the antioxidant capacity of grape pomace in sunflower oil was evaluated using OSI. It increased the oil’s stability by up to 42.5%, positioning grape pomace extracts as a source of natural antioxidants in vegetable oils. Full article

Ferritin, an emerging protein resource, has garnered significant attention in scientific research due to its biocompatibility and unique cavity structure capable of encapsulating bioactive compounds. This study aimed to optimize ultrasound-assisted extraction (UAE) for enhancing ferritin yield from northern pike liver byproducts and evaluate its potential as a nanocarrier for chlorogenic acid (CA). Through response surface methodology (RSM), the optimal UAE parameters were established as 200 W ultrasonic power, 1:3 solid–liquid ratio, and 25 min extraction time. Under these conditions, the ferritin extraction yield reached 139.46 mg/kg, representing a 4.02-fold increase compared to conventional methods (34.65 mg/mL). Electrophoretic analysis confirmed the electrophoretic purity of the extracted liver ferritin. Comprehensive characterization using UV-vis spectroscopy, FTIR, and fluorescence spectroscopy revealed preserved structural integrity of UAE-extracted ferritin. Homology modeling provided molecular insights into the ferritin architecture. Successful encapsulation of CA was achieved with an encapsulation efficiency of 13.25%, as quantified by HPLC. Analysis by DLS and ζ potential as well as TG and DSC showed that not only the thermal stability of CA was enhanced after ferritin encapsulation, but also that the ferritin remained stable with a cage-like structure. This investigation establishes UAE as an effective strategy for valorizing fish processing byproducts through high-yield ferritin extraction while demonstrating the protein’s functional capacity as a nanocarrier for bioactive compound delivery. The findings highlight the dual advantage of sustainable resource utilization and advanced delivery system development through this biotechnological approach. Full article