Search Results (1,077)

A chemical investigation of the EtOAc fraction from soft coral Clavularia viridis resulted in the isolation of 12 undescribed dolabellane-type diterpenoids, namely clavirolides W–Z (1–4), clavularols A–H (5–12), and three known analogs (13–15). Their structures were characterized by an extensive analysis of spectroscopic data, including X-ray diffraction and ECD calculations for the assignment of absolute configurations. The structures of 2 and 4–6 are feathered as peroxyl-substituted derivatives, while compounds 7–12 possess additional oxidative cyclization, including epoxide or furan that are rare in the dolabellane family. All these compounds were evaluated for activities on cytotoxic and anti-inflammatory models. Compound 10 exhibited most potential against NO production in the BV2 cell induced by LPS with an IC₅₀ value of 18.3 μM. Full article

To explore the potential seed compounds from natural products as anticancer agents against small-cell lung cancer (SCLC), the underground parts of Agapanthus africanus, a plant commonly used for ornamental purposes, were investigated. Three spirostan-type steroidal glycosides (1–3) were isolated and identified by nuclear magnetic resonance spectral analysis. Compounds 1–3 exhibited cytotoxicity against SBC-3 human SCLC cells, with IC₅₀ values of 0.56, 1.4, and 7.4 µM, respectively. Compound 1, also known an agapanthussaponin A, demonstrated the most potent cytotoxicity among the isolated compounds and was evaluated for its apoptosis- and ferroptosis-inducing activities. Compound 1 arrested the cell cycle of SBC-3 cells in the G₂/M phase and induced apoptosis primarily via the mitochondrial pathway, characterized by caspases-3 and -9 activation, loss of mitochondrial membrane potential, and overproduction of reactive oxygen species. Additionally, 1 triggered ferroptosis via a dual mechanism consisting of enhanced cellular iron uptake through upregulation of transferrin and transferrin receptor 1 expression and impaired glutathione synthesis via downregulation of both xCT and glutathione peroxidase 4 expression. Compound 1 induces cell death via the apoptosis and ferroptosis pathways, suggesting its promise as a seed compound for the development of anticancer therapeutics against SCLC. Full article

In this article, an efficient and straightforward protocol for the construction of complex dispirocyclic skeletons via regioselective intramolecular Michael addition is presented. Diverse dispirocyclic compounds were synthesized under mild and transition-metal-free conditions with good to excellent yields. Most stereoisomers were conveniently separated by column chromatography, and their relative configurations were identified by single-crystal X-Ray diffraction of representative compounds. A scale-up experiment validated the practicality of this method. In an in vitro assay, some dispirocyclic compounds exhibited potent cytotoxicity with an IC₅₀ value of 10⁻⁶ mol/L. Full article

This study investigates the co-pyrolysis behavior of two lignocellulosic biomass blends, bamboo (B), and rice straw (R) with a plastic polyethylene (P). A total of 15 samples, including binary and ternary blends, were analyzed. Firstly, X-ray diffraction (XRD) analysis was performed to reveal high crystallinity in the B25R75 blend (I/I_c = 13.39). Whereas, the polyethylene samples showed persistent ZrP₂O₇ and lazurite phases (I/I_c up to 3.12) attributed to additives introduced during the manufacturing of the commercial plastic feedstock. In addition, scanning electron microscopy with energy-dispersive X-ray (SEM-EDX) spectroscopy was performed to characterize the surface morphology and elemental composition of the feedstock. Moreover, thermogravimetric analysis (TGA) was employed at temperatures up to 700 °C at three different heating rates (5, 10, and 20 °C/min) under pyrolysis conditions. Kinetic analysis used TGA data to calculate activation energy via Friedman’s isoconversional method, and the blended samples exhibited a decrease in activation energy compared to the individual components. Furthermore, the study evaluated transient interaction effects among the components by assessing the deviation between experimental and theoretical weight loss. This revealed the presence of significant synergistic behavior in certain binary and ternary blends. The results demonstrate that co-pyrolysis of bamboo and rice straw with polyethylene enhances thermal decomposition efficiency and provides a more favorable energy recovery route. Full article

This study explores the valorization of agro-industrial by-products—riceberry broken rice (RBR) and soybean meal (SBM)—as cost-effective substrates for enhancing exopolysaccharide (EPS) production by Bacillus tequilensis PS21. Eight Bacillus strains were screened, and B. tequilensis PS21 demonstrated the highest EPS yield (2.54 g/100 mL DW). The EPS displayed a strong antioxidant capacity with 65.5% DPPH and 80.5% hydroxyl radical scavenging, and a FRAP value of 6.51 mg Fe²⁺/g DW. Antimicrobial testing showed inhibition zones up to 10.07 mm against Streptococcus agalactiae and 7.83 mm against Staphylococcus aureus. Optimization using central composite design (CCD) and the response surface methodology (RSM) revealed the best production at 5% (w/v) RBR, 3% (w/v) SBM, pH 6.66, and 39.51 °C, yielding 39.82 g/L EPS. This EPS is a moderate-molecular-weight (11,282 Da) homopolysaccharide with glucose monomers. X-ray diffraction (XRD) showed an amorphous pattern, favorable for solubility in biological applications. Thermogravimetric analysis (TGA) demonstrated thermal stability up to ~250 °C, supporting its suitability for high-temperature processing. EPS also exhibited anticancer activity with IC₅₀ values of 226.60 µg/mL (MCF-7) and 224.30 µg/mL (HeLa) at 72 h, reduced colony formation, inhibited cell migration, and demonstrated anti-tyrosinase, anti-collagenase, and anti-elastase effects. This study demonstrates the successful valorization of agro-industrial by-products—RBR and SBM—for the high-yield production of multifunctional EPS with potent antioxidant, antimicrobial, and anticancer properties. The findings highlight the sustainable potential of these low-cost substrates in supporting the development of green and value-added bioproducts, with promising utilizations across the food, pharmaceutical, and cosmetic sectors. Full article

To explore the dyeing technique and karyotype analysis of winter turnip rape (Brassica rape L.), the root tip of winter turnip rape Longyou 7 was used as the experimental material. Chromosome preparation technology was optimized, and karyotype analysis was carried out by changing the conditions of material collection time, pretreatment, fixation, and dissociation. The results showed that the optimal conditions for the preparation of dyeing winter turnip rape were as follows: the sampling time was 8:00–10:00, the ice–water mixture was pretreated at 4 °C for 20 h, the Carnot’s fixative solution I and 4 °C were fixed for 12 h, and the 1 mol/L HCl solution was bathed in a water bath at 60 °C for 10~15 min. Karyotype analysis showed that the number of chromosomes in winter turnip rape cells was 2n = 20, and the karyotype analysis formula was 2n = 2x = 20 = 16m + 4sm. The karyotype asymmetry coefficient was 58.85%, and the karyotype type belonged to type 2A, which may belong to the primitive type in terms of evolution. The results of this study provide a theoretical basis for further in-depth study of the phylogenetic evolution and genetic trend of Brassica rapa. Full article

Mining waste presents significant environmental and public health risks due to the potential release of toxic substances when improperly managed. In this study, four tailings samples were taken to evaluate the environmental risks in the Ponce Enríquez mining area in Ecuador. Chemical characterization and X-ray Fluorescence Spectrometry (XRF) were used to analyze the content of potentially toxic elements (PTEs) of interest (As, Cd, Cr, Cu, Ni, Pb, and Zn), and X-ray Diffraction (XRD) for mineralogical characterization. The contamination index (IC) was calculated to assess the potential hazard associated with the content of PTEs in the mining wastes. To assess environmental risks, leaching tests were carried out to evaluate the potential release of PTEs, and Acid-Base Accounting (ABA) tests were conducted to determine the likelihood of acid mine drainage formation. The results revealed that the PETs concentration exceeded the maximum permissible limits in all samples, according to Ecuadorian regulations: As, Pb, and Cd were identified as critical contaminants. Mineralogically, quartz was the dominant phase, followed by carbonates (calcite, dolomite and magnesite), phyllosilicates (chlorite and illite), and minor amounts of pyrite and talc. The IC indicated high to very high contamination risk levels, with As being the predominant contributor. Although leaching tests met the established limits for non-hazardous mining waste, the ABA test showed that all samples had a high potential for long-term acid generation. These results underscore the need for implementing management strategies to mitigate the environmental impacts and the development of plans to protect local ecosystems and communities from the adverse effects of mining activities. Full article

Marine algae offer environmentally friendly platforms for green nanoparticle synthesis. This study reports the biosynthesis of silver nanoparticles using polysaccharides isolated from the brown alga Chnoospora minima (PAgNPs) and evaluates their therapeutic potential. Fourier Transform Infrared Spectroscopy (FTIR) confirmed algal polysaccharide functional groups. Dynamic Light Scattering (DLS), Scanning Electron Microscopy (SEM), and Energy Dispersive X-ray (EDX) analysis characterized the nanoparticles as spherical (~84 nm average size), stable (zeta potential −18.5 mV), and containing elemental silver without nitrogen. The PAgNPs exhibited potent antioxidant activity (~100% DPPH scavenging) and significant antimicrobial efficacy, particularly against Staphylococcus aureus and Candida species. Crucially, PAgNPs displayed potent antiproliferative activity against human lung cancer cells (A549, IC₅₀: 13.59 µg/mL). In contrast, toxicity to normal Vero cells was significantly lower (IC₅₀: 300.2 µg/mL), demonstrating notable cancer cell selectivity (SI 22.1). Moderate activity was observed against MCF-7 breast cancer cells (IC₅₀: 100.7 µg/mL). These results demonstrate that C. minima polysaccharide facilitates the synthesis of biocompatible AgNPs with promising antimicrobial and selective anticancer capabilities, highlighting their potential for further development as nanotherapeutics. Full article

The Shapley Supercluster, one of the largest and most massive structures in the nearby (redshift $z\le 0.1$) Universe, located approximately 200 Mpc away, is a unique laboratory for high-energy astrophysics. Galaxy clusters that comprise it are promising targets for multimessenger study due to the presence in the intracluster medium of the necessary conditions for the acceleration of cosmic rays up to ultra-high energies and the generation by them of non-thermal electromagnetic and neutrino emission. Using the Shapley Supercluster’s observational data from the recent eROSITA-DE Data Release, we recover the physical parameters of 45 X-ray luminous galaxy clusters and calculate the expected multiwavelength—from radio to very-high-energy γ-ray as well as neutrino emission, with a particular focus on hadronic interactions of accelerated cosmic ray nuclei with the nuclei of the intracluster medium. The results obtained allow verification of cluster models based on multimessenger observations of clusters, especially in $\gamma$-ray (Fermi-LAT, H.E.S.S., CTAO-South for the Shapley Supercluster case), and neutrino (Ice Cube, KM3NeT). We also estimate the ability of the Shapley Supercluster to manifest as cosmic Zevatrons and show that it can contribute to the PAO Hot Spot in the Cen A region at UHECR energies over 50 EeV. Full article

Background/Objectives: The development of antitumor agents possessing low toxicity against non-cancerous cells is still a challenge in medicinal chemistry. In this paper, we report the antitumor activity of “hybrid structures” derived from the amino acid taurine. We have synthesized 26 compounds, structures of which were confirmed using NMR, X-ray diffractometry, and other techniques. Cytotoxicity of the obtained compounds has been evaluated using three human cancer cell lines. Pyrrolidine 4p has exhibited the strongest antiproliferative activity against HL-60 cells with an IC₅₀ of 76.7 μM, while IC₅₀ against normal cells was 176.3 μM. Water-soluble derivatives of taurine have been tested for antileukemia activity in mice of the BDF1 line. Compound 4p has been identified as the leading compound, which increases the mean survival time of mice from 40 to 100% as compared to the control group. Together, these results prove that taurine-based hybrid structures can be a promising scaffold for the discovery of potential antiproliferative agents. Full article

In the present research, metal–organic framework-5 (MOF-5) was synthesized and loaded with zerumbone (ZER@MOF-5), followed by the evaluation of its anticancer, antibacterial, antifungal, DNA-binding, and free radical scavenging potentials. The synthesized nanoparticles were characterized using X-ray diffraction, ultraviolet–visible spectroscopy, Fourier-transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, and scanning electron microscopy. The in vitro anticancer activity of ZER@MOF-5 was studied in a human breast cancer cell line (MCF-7) using the CCK-8 assay. The interaction of ZER@MOF-5 with pBR322 plasmid DNA was assessed by gel electrophoresis. The antimicrobial effect of ZER@MOF-5 was examined in gram-positive and gram-negative bacterial strains and yeast strains using the microdilution method. The free radical scavenging activity was assessed using the DPPH assay. Cytotoxicity assay revealed a notable enhancement in the anticancer activity of zerumbone upon its encapsulation into MOF-5. The IC₅₀ value for ZER@MOF-5 was found to be 57.33 µg/mL, which was lower than that of free zerumbone (IC₅₀: 89.58 µg/mL). The results of the DNA-binding experiment indicate that ZER@MOF-5 can bind to target DNA and cause a conformational change in DNA. The results of the antibacterial activity experiment showed that the antibacterial ability of ZER@MOF-5 was limited compared to free zerumbone. The results of the DPPH assay demonstrated that the antioxidant activity of free zerumbone was higher than that of ZER@MOF-5. MOFs encapsulate compounds within their porous crystalline structure, which leads to prolonged circulation time compared to single ligands. Although the unique structure of MOFs may limit their antibacterial and antioxidant activity in the short term, it may increase therapeutic efficacy in the long term. However, to fully understand the long-term antibacterial and antioxidant effects of the ZER@MOF-5, further comprehensive in vitro and in vivo experiments are necessary. This finding indicates that the MOF-5 could potentially be an impressive carrier for the oral administration of zerumbone. Full article

(1) Background: Our study investigates the green synthesis of Ag₂O/Ag nanoparticles using the isoflavone Puerarin as a bioreductor. (2) Methods: The PUE@Ag₂O/Ag nanoparticles were characterized using various techniques, including X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), electronic microscopy (TEM, SEM), energy dispersive X-ray spectroscopy (EDX), and dynamic light scattering (DLS). Biological activities were assessed through antimicrobial testing, cytotoxicity assays on human keratinocytes and melanoma cells, and an in ovo screening using the HET-CAM assay. (3) Results: The formation of crystalline Ag₂O/Ag nanoparticles with sizes below 100 nm was accomplished with Puerarin. Despite their high cytotoxicity at all tested concentrations, the nanoparticles showed antioxidant activity with IC₅₀ 981.5 ± 94.2 μg/mL, antibacterial activity against several clinically relevant nosocomial strains (Streptococcus pyogenes, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa), and no local irritant effects or inhibition of angiogenesis in the HET-CAM assay. (4) Conclusions: This study provides insights into the synthesis, characterization, and biological profile of PUE@Ag₂O/Ag nanoparticles for potential biomedical applications. Full article

Silicon alloy-based materials are widely studied as high-capacity anode materials to replace commercial graphite in lithium-ion batteries (LIBs). Among these, silicon suboxide (SiO_x) offers superior cycling performance compared to pure Si-based materials. However, achieving a high initial Coulombic efficiency (ICE) remains a key challenge. To address this, previous studies have explored Si_xO composites (x ≈ 1, 2), where nano-Si is uniformly dispersed within a Si suboxide matrix to enhance ICE. While this approach improves reversible capacity and ICE compared to conventional SiO, it still falls short of the capacity achieved with pure Si. This study employs a high-energy mechanical milling approach with increased Si content to achieve higher reversible capacity and further enhance the ICE while also examining the effects of trace oxygen uniformly distributed within the Si suboxide matrix. Structural characterization via X-ray diffraction, Raman spectroscopy, and electron microscopy confirm that Si crystallites (<10 nm) are homogeneously embedded within the SiO_x matrix, reducing crystalline Si size and inducing partial amorphization. Electrochemical analysis demonstrates an ICE of 89% and a reversible capacity of 2558 mAh g⁻¹, indicating significant performance improvements. Furthermore, carbon incorporation enhances cycling stability, underscoring the material’s potential for commercial applications. Full article

Combining biosynthetic gene cluster analysis with the OSMAC strategy, fractionation of the fermentation extract of Aspergillus templicola from the sponge Agelas sp. led to the isolation of four novel cytochalasins, colachalasins J–M (1–4), a novel cyclic pentapeptide, avellanin P (5), together with five known compounds (6–10). The structures of 1–9 were elucidated using spectroscopic data, single crystal X-ray diffraction, and Marfey’s analysis. Compound 2 exhibited potent anti-inflammatory activity in zebrafish assays. Additionally, Compounds 4 and 6 showed modest cytotoxicity against several human cancer cell lines with IC₅₀ values ranging from 2.6 to 11.2 μm. Full article

In this study, we investigated how to design a tube furnace for the oxygen annealing of a REBa₂Cu₃O_7−x (REBCO, where RE = rare earth) superconducting joint. We confirmed the annealing temperature threshold of REBCO tape I_c degradation, which was 175C. A heat exchange model that included REBCO tape and a tube furnace was established by using this temperature as the boundary condition. At the same time, the temperature distribution of the REBCO tape in a commercial tube furnace was measured for the calibration of the heat exchange model. The feasibility and accuracy of the model were confirmed by comparing the real measurements and the simulation results. We then optimized the furnace design based on the model according to two criteria: a 20 mm length of REBCO tape should be kept at high temperatures for the oxygen annealing of REBCO joints and the length of tape at temperatures over the I_c degradation temperature should be as short as possible. The results of this furnace design investigation could help fabricate shorter REBCO superconducting joints, making the magnet more compact and decreasing the length of the Cu stabilizer layer to be removed. Full article