Search Results (4,922)

In this paper, we study the Bochner modular relation (Lambert series) for the kth power of the product of two Riemann zeta-functions with difference $\alpha$, an integer with the Voronoĭ function weight $V_k$. In the case of $V_1\left(x\right)=e^{-x}$, the results reduce to Bochner modular relations, which include the Ramanujan formula, Wigert–Bellman approximate functional equation, and the Ewald expansion. The results abridge analytic number theory and the theory of modular forms in terms of the sum-of-divisor function. We pursue the problem of (approximate) automorphy of the associated Lambert series. The $\alpha =0$ case is the divisor function, while the $\alpha =1$ case would lead to a proof of automorphy of the Dedekind eta-function à la Ramanujan. Full article

Microplastic (MPs) pollution has emerged as a critical environmental issue due to its persistent accumulation in ecosystems, posing risks to aquatic life, food safety, and human health. In this study, magnetic Fe₃O₄ nanoparticles functionalized with citric acid (Fe₃O₄@AC) were used to remove high-density polyethylene (HDPE), low-density polyethylene (LDPE), and polypropylene (PP) MPs from an aqueous medium. Fe₃O₄@AC was synthesized via the coprecipitation method and characterized by morphology (SEM), crystalline phases (XRD), chemical aspects (FTIR), and surface area (nitrogen sorption isotherms). The MPs removal efficiency of Fe₃O₄@AC was evaluated based on the initial concentration, contact time, and pH. The adsorption isotherm and kinetics data were best described by the Sips and pseudo-second-order models, respectively. Fe₃O₄@AC removed 80% of the MPs at a pH of 6. Based on experimental observations (zeta potential, porosity, and SEM) and theoretical insights, it was concluded that hydrogen bonding, pore filling, and van der Waals forces governed the adsorption mechanism. Reusability tests showed that Fe₃O₄@AC could be reused up to five times, with a removal efficiency above 50%. These findings suggest that Fe₃O₄@AC is a sustainable and promising material for the efficient removal of microplastics from wastewater, offering a reusable and low-impact alternative that contributes to environmentally responsible wastewater treatment strategies. Full article

Blackseed oil supplemented with caseinate (CA)–carboxymethyl chitosan (CMCH) composite membranes were evaluated for their functional properties and as edible coating for extending the shelf life of grape tomatoes. Composite films were prepared from equal parts of (CaCa or NaCa) and (CMCH) with or without supplemented 3% blackseed oil (BO) and evaluated for their functional properties. Subsequently, the edible membrane coating was evaluated to extend the shelf life of grape tomatoes (Solanum lycopersicum L.). The water vapor permeability (WVP) of the films was the lowest for the calcium caseinate–carboxymethyl chitosan–blackseed oil (CaCa-CMCH-BO) film (3.01 g kPa⁻¹ h⁻¹ m⁻²). Adding blackseed oil to the edible film matrix also led to a significant increase in its mechanical properties, resulting in tensile strength values of 12.5 MPa and 10.2 MPa and elongation at break values of 90.5% and 100% for NaCa-CMCH-BO and CaCa-CMCH-BO, respectively. The composite films also exhibited good compatibility through hydrogen bonding and hydrophobic interactions, as confirmed by FTIR spectroscopy. The particle size and zeta potential of CaCa-CMCM-BO were 117 nm and −40.73 mV, respectively, while for NaCa-CMCH-BO, they were 294.70 nm and −25.10 mV, respectively. The incorporation of BO into the films resulted in greater antioxidant activity. When applied as an edible film membrane on grape tomatoes, the coating effectively delayed the deterioration of tomatoes by reducing weight loss, microbial spoilage, and oxidative degradation. Compared to the control, the coated fruits had delayed ripening, with a shelf life of up to 30 days, and reduced microbial growth over the entire storage period. Full article

This study describes the development, characterization and in vitro evaluation of poly(ε-caprolactone) (PCL) nanoparticles loaded with xanthyletin for the control of Atta sexdens rubropilosa through the inhibition of its symbiotic fungus Leucoagaricus gongylophorus. Nanoparticles were prepared via interfacial polymer deposition, with formulation NC5 selected based on optimal physicochemical properties. NC5 exhibited an encapsulation efficiency of 98.0%, average particle size of 304 nm and zeta potential of −29.3 mV. Scanning electron microscopy confirmed spherical morphology and the absence of crystalline residues. The formulation remained physically stable for four months at 4 °C. In vitro release showed biphasic behavior, with an initial burst followed by sustained release. Under UV exposure, NC5 enhanced xanthyletin photostability by 15.4-fold compared to the free compound. Fungicidal assays revealed 76% inhibition of fungal growth with NC5, compared to 85% with free xanthyletin. These results support the potential application of xanthyletin-loaded PCL nanoparticles as a stable and controlled delivery system for the biological control of leaf-cutting ants by targeting their fungal mutualist. Further in vivo studies are recommended to assess efficacy under field conditions. Full article

Background: Exosomes have recently attracted significant attention for their potential in drug delivery. Plant-derived exosomes, in particular, may serve as direct anticancer agents due to their unique characteristics, including immunogenicity, biocompatibility, safety, cell-free nature, and nanoscale structure. Methods: This study characterizes Persea americana (avocado)-derived exosomes, exploring their anticancer properties, proteomic profile, and therapeutic potential. Results: Isolated exosomes exhibited a diameter of 99.58 ± 5.09 nm (non-loaded) and 151.2 ± 6.36 nm (doxorubicin (DOX)-loaded), with zeta potentials of −17 mV and −28 mV, respectively. Proteomic analysis identified 47 proteins, including conserved exosome markers (GAPDH, tubulin) and stress-response proteins (defensin, endochitinase). Functional enrichment revealed roles in photosynthesis, glycolysis, ATP synthesis, and transmembrane transport, supported by protein–protein interaction networks highlighting energy metabolism and cellular trafficking. DOX encapsulation efficiency was 18%, with sustained release (44.4% at 24 h). In vitro assays demonstrated reduced viability in breast cancer (MCF-7, T47D, 4T1) and endothelial (C166) cells, enhanced synergistically by DOX (Av+DOX). Gene expression analysis revealed cell-specific modulation: Av+DOX upregulated TP53 and STAT in T47D but suppressed both in 4T1/C166, suggesting context-dependent mechanisms. Conclusions: These findings underscore avocado exosomes as promising nanovehicles for drug delivery, combining biocompatibility, metabolic functionality, and tunable cytotoxicity. Their plant-derived origin offers a scalable, low-cost alternative to mammalian exosomes, with potential applications in oncology and targeted therapy. Further optimization of loading efficiency and in vivo validation are warranted to advance translational prospects. Full article

A comprehensive investigation of the chemical bonding, electronic structure, and spectroscopic properties of the lanarkite-type Pb₂SO₅ (PSO) structure was conducted, for the first time, using density functional theory simulations. Thus, different functionals, PBE, PBE0, PBESOL, PBESOL0, BLYP, WC1LYP, and B3LYP, were used, and their results were compared to predict their fundamental properties accurately. All DFT calculations were performed using a triple-zeta valence plus polarization basis set. Among all the DFT functionals, PBE0 showed the best agreement with the experimental and theoretical data available in the literature. Our results also reveal that the [PbO₅] clusters were formed with five Pb–O bond lengths, with values of 2.29, 2.35, 2.57, 2.60, and 2.79 Å. Meanwhile, the [SO₄] clusters exhibited uniform S–O bond lengths of 1.54 Å. Also, a complete topological analysis based on Bader’s Quantum Theory of Atoms in Molecules (QTAIM) was applied to identify atom–atom interactions in the covalent and non-covalent interactions of the PSO structure. Additionally, PSO has an indirect band gap energy of 4.83 eV and an effective mass ratio ($m_h^{*}$/$m_e^{*}$) of about 0.192 (PBE0) which may, in principle, indicate a low degree of recombination of electron–hole pairs in the lanarkite structure. This study represents the first comprehensive DFT investigation of Pb₂SO₅ reported in the literature, providing fundamental insights into its electronic and structural properties. Full article

Hypericum perforatum L. (H.P.), a plant renowned for its wound-healing properties, was investigated for antioxidant/antimicrobial efficacy, toxicological safety, and in vivo wound-healing effects in this research to develop and characterize novel nanoemulsion hydrogel (NG) formulations. NG were prepared via emulsion diffusion–solvent evaporation and polymer hydration using Cremophor RH40 and Ultrez 21/30. A D-optimal design optimized oil/surfactant ratios, considering particle size, PDI, and drug loading. Antioxidant activity was tested via DPPH, ABTS⁺, and FRAP. Toxicological assessment followed HET-CAM (ICH-endorsed) and ICCVAM guidelines. The optimized NG-2 (NE-HPM-10 + U30 0.5%) demonstrated stable and pseudoplastic flow, with a particle size of 174.8 nm, PDI of 0.274, zeta potential of −23.3 mV, and 99.83% drug loading. Release followed the Korsmeyer–Peppas model. H.P. macerates/NEs showed potent antioxidant activity (DPPH IC₅₀: 28.4 µg/mL; FRAP: 1.8 mmol, Fe²⁺/g: 0.3703 ± 0.041 mM TE/g). Antimicrobial effects against methicillin-resistant S. aureus (MIC: 12.5 µg/mL) and E. coli (MIC: 25 µg/mL) were significant. Stability studies showed no degradation. HET-CAM tests confirmed biocompatibility. Histopathology revealed accelerated re-epithelialization/collagen synthesis, with upregulated TGF-β1. The NG-2 formulation demonstrated robust antioxidant, antimicrobial, and wound-healing efficacy. Enhanced antibacterial activity and biocompatibility highlight its therapeutic potential. Clinical/pathological evaluations validated tissue regeneration without adverse effects, positioning H.P.-based nanoemulsions as promising for advanced wound care. Full article

Semicrystalline polystyrene spheroidal nanoparticles (50–100 nm) were obtained via microemulsion polymerization. They were evaluated as coal collectors in a low-rank carbonaceous mineral containing 2% organic carbon. The recovery of coal using nanoparticles as collectors was 88.2%, in contrast to 53.2%, 46.4%, and 44.8% achieved using an amine-type compound, kerosene, and diesel, respectively. X-ray photoelectron spectroscopy (XPS) and zeta potential measurements confirmed the polystyrene–mineral surface chemical interaction. A Box–Behnken experimental design for flotation optimization was applied, and the results showed that the coal recovery increased up to 99.5% when the dosage of the collector was increased. A contact angle study and density functional theory calculations, together with XPS results, allowed us to postulate an interaction mechanism in which polystyrene nanoparticles adsorb onto the coal surface through hydrophobic interactions, rendering the oxidized surface hydrophobic and the coal buoyant by adhering to the gas bubbles. Full article

Modern dermocosmetics combine the effectiveness of active substances with the benefits of percutaneous penetration enhancers to address skin issues such as hyperpigmentation. In this study, three bioactive tripeptides (with amino acid sequences CSF, CVL, and CSN) with previously confirmed tyrosinase inhibition activity were synthesized using the solid-phase synthesis method. The structures of the obtained peptides were determined. In addition, elastase in silico and in vitro inhibition assays were carried out. The tripeptides were subsequently encapsulated into liposomes, for which key physicochemical parameters were determined, including size, zeta potential, and encapsulation efficiency. The average diameter of the prepared liposomes was approximately 100 nm across all samples. The prepared carriers were found to be stable and exhibited no cytotoxicity toward reconstructed human epidermis cells. The peptides achieved an encapsulation efficiency of approximately 20–30%, with no significant differences observed between the cationic and anionic vesicles. Liposomes containing the CSF tripeptide, which showed the strongest tyrosinase-inhibiting effect, did not transport the peptide through the human skin in an ex vivo assay to permit quantification in the receptor solution, but facilitated penetration and retention of the tripeptide within the epidermis (4.65 ± 1.81 μg/cm²). These findings suggest that the prepared liposomes may serve as valuable carriers of bioactive tripeptides in anti-aging cosmetics. Full article

This study evaluated two techniques for encapsulating Lactiplantibacillus plantarum using bovine lactoferrin and sodium alginate. The first method involved a layer-by-layer (LbL) coating of lactoferrin and alginate directly onto individual cells, using three layers of these electrolytes. The second method focused on encapsulating the probiotics in calcium alginate miniaturized beads, followed by a lactoferrin coating (AAcL). Encapsulation efficiency was measured at 52.7% for the LbL method and 32.6% for AAcL. Encapsulation was confirmed through zeta potential changes and scanning electron microscopy (SEM) micrographs. After freeze drying, the LbL technique showed a 2.67 log CFU decrease in survival rates, whereas the AAcL method resulted in a 3.77 log CFU decline. Nonencapsulated probiotics experienced a reduction of 5.8 log CFU. In storage at −20 °C, the LbL method led to a 32% decrease in survival after 30 days and 41% after 90 days, while the AAcL method showed a decline of 15% after 30 days and 28% after 90 days. Both techniques preserved 75% of the initial L. plantarum population under simulated gastrointestinal conditions. Overall, these methods effectively protected the probiotic from environmental stress. Full article

The development of eco-friendly surfactants is pivotal for enhanced oil recovery (EOR). In this study, a novel lignin-derived zwitterionic surfactant (DMS) was synthesized through a two-step chemical process involving esterification and free radical polymerization, utilizing renewable alkali lignin, maleic anhydride, dimethylamino propyl methacrylamide (DMAPMA), and sulfobetaine methacrylate (SBMA) as precursors. Comprehensive characterization via ¹H NMR, FTIR, and XPS validated the successful integration of amphiphilic functionalities. Hydrophilic–lipophilic balance (HLB) analysis showed a strong tendency to form stable oil-in-water (O/W) emulsions. The experimental results showed a remarkable 91.6% viscosity reduction in Xinjiang heavy crude oil emulsions at an optimum dosage of 1000 mg/L. Notably, DMS retained an 84.8% viscosity reduction efficiency under hypersaline conditions (total dissolved solids, TDS = 200,460 mg/L), demonstrating exceptional salt tolerance. Mechanistic insights derived from zeta potential measurements and molecular dynamics simulations revealed dual functionalities: interfacial modification by DMS-induced O/W phase inversion and electrostatic repulsion (zeta potential: −30.89 mV) stabilized the emulsion while disrupting π–π interactions between asphaltenes and resins, thereby mitigating macromolecular aggregation in the oil phase. As a green, bio-based viscosity suppressor, DMS exhibits significant potential for heavy oil recovery in high-salinity reservoirs, addressing the persistent challenge of salinity-induced inefficacy in conventional chemical solutions and offering a sustainable pathway for enhanced oil recovery. Full article

Microbial transglutaminase (mTG) is most frequently utilized in order to increase the gelling properties of soybean protein isolate (SPI), but there are still some limitations of mTG-based hydrogel fabrication technology. Therefore, we aimed to develop a dual modification technique based on enzyme plus organic acid treatment to fabricate SPI hydrogels with high gel strength and stability. Our results showed that mTG plus glucose-δ-lactone (GDL), lactobionic acid (LBA) or maltobionic acid (MBA) treatment could significantly improve the gel strength, textural properties, and water-holding capacity of SPI hydrogels. Also, the addition of these organic acids remarkably reduced the surface hydrophobicity (H₀) and intrinsic fluorescence as well as increased the storage modulus (G′), loss modulus (G″) values, average particle size, and the absolute value of zeta potential of samples. GDL, LBA, or MBA greatly increased the β-sheet level and decreased the α-helix level in hydrogels, as well as dissociated 11S subunits of SPI into 7S subunits. Notably, covalent interactions, hydrogen bonding, and hydrophobic interactions of three organic acids with SPI, as well as the effects of organic acids on the interactions among the intramolecular and intermolecular forces of SPI molecules, contributed to their promoting effects on the formation of hydrogels. The LF-NMR and SEM analyses confirmed the effects of GDL, LBA, and MBA on converting the free water into immobilized and bound water as well as forming a dense stacked aggregate structure. Therefore, GDL, LBA, and MBA are promising agents to be combined with mTG in the fabrication of SPI hydrogels with high gel strength and stability. Full article

Background/Objectives: Acne vulgaris is a chronic skin infection characterized by high sebum secretion, keratosis around hair follicles, inflammation, and imbalance in androgen levels. Acne vulgaris causes permanent scars or skin pigmentation in cases of improper treatment. Oral or topical isotretinoin, contraceptives, and antibiotics are used to treat acne. Minocycline is one of the widely used tetracyclines for this purpose; it inhibits the synthesis of proteins in bacterial ribosomes. Commonly, minocycline is prescribed daily for several months for acne vulgaris. Systemic minocycline is highly distributed into body fluids, and it is associated with several side effects and antibiotic resistance. Additionally, minocycline is highly metabolized in the liver, leading to reduced bioavailability upon systemic delivery. This study aims to develop and characterize minocycline nanocrystals for targeted skin delivery and evaluate their antimicrobial efficacy in treating acne vulgaris. Methods: Minocycline nanocrystals were synthesized using milling or solvent evaporation techniques. Nanocrystals were characterized in terms of particle size, particle distribution index (PDI), zeta potential, and morphology. The antibacterial efficacy against Propionibacterium acne, Staphylococcus aureus, and Staphylococcus epidermidis was evaluated using a minimum inhibitory concentration assay (MIC) and agar well diffusion test in comparison to coarse minocycline. Results: Minocycline nanocrystals had a particle size of 147.4 ± 7.8 nm and 0.27 ± 0.017 of PDI. The nanocrystals exhibited a loading efficiency of 86.19 ± 16.7%. Antimicrobial testing showed no significant difference in activity between minocycline and its nanoparticle formulation. In terms of skin deposition, the nanocrystals were able to deliver minocycline topically to rat skin significantly more than free minocycline. The nanocrystal solution deposited 554.56 ± 24.13 μg of minocycline into rat skin, whereas free minocycline solution deposited 373.99 ± 23.32 μg. Conclusions: Minocycline nanocrystals represent a promising strategy for targeted skin delivery in the treatment of acne vulgaris, potentially reducing systemic side effects and antibiotic resistance and improving patient outcomes. Full article

The aim of this study was to investigate the effect of Ostwald ripening inhibitors on D-limonene (D-LMN) nanoemulsions and to elucidate their impact on oral cancer cells. Various inhibitors, including olive oil, soybean oil, and perilla oil, were incorporated into D-LMN nanoemulsions at different ratios (25:75–75:25, D-LMN to inhibitor). The resulting nanoemulsions were evaluated for droplet size, size distribution, zeta potential, stability, droplet morphology, cytotoxicity, antimetastatic and anti-invasive activities, apoptosis induction, and cell cycle arrest. Results showed that the 75:25 D-LMN to inhibitor ratio produced the smallest droplet size and exhibited great stability, particularly with perilla oil. Notably, D-LMN nanoemulsions displayed strong anti-oral cancer effects by reducing cell viability, metastasis, and invasion. Apoptosis was induced, as evidenced by nuclear fragmentation, Annexin V binding, and altered expression of BAX, BCL-XL, Cytochrome c, and Caspase-9. Additionally, the nanoemulsions caused cell cycle arrest via downregulation of Cyclin D1, CDK2, CDK4, and CDK6. These findings highlight the potential of D-LMN nanoemulsions as a promising alternative therapeutic strategy for oral cancer treatment. Full article

Objectives: This study characterised and evaluated the stability, solubility, and in vitro drug release of OA- and AA-loaded SLNs. Methods: The OA- and AA-SLNs were formulated using the emulsion solvent evaporation method and characterised based on particle size (PS), polydispersity index (PDI), zeta potential (ZP), and transmission electron microscopy (TEM). Solubility studies were conducted in PBS (pH 1.2 and 6.8) and dH₂O using HPLC, while in vitro drug release was assessed in simulated intestinal fluid (SIF) (pH 6.8). Results: The optimised OA-SLNs (1:1 drug-to-lipid ratio) showed PS, PDI, ZP, and EE% values of 312.9 ± 3.617 nm, 0.157 ± 0.014, −17.0 ± 0.513 mV, and 86.54 ± 1.818%, respectively. The optimised AA-SLNs (1:2 drug-to-lipid: ratio) had a PS of 115.5 ± 0.458 nm, PDI of 0.255 ± 0.007, ZP of −11.9 ± 0.321 mV, and EE% of 76.22 ± 0.436%. The SLNs remained stable for 60 days at 4 °C and room temperature (p < 0.05). The solubility study revealed that free OA and AA showed no measurable values in the three solvents. However, OA-SLNs showed the highest solubility in H₂O (16-fold) followed by PBS at pH 6.8 (10-fold) and pH 1.2 (10-fold). AA-SLNs significantly improved the solubility in PBS at pH 6.8 (88-fold), compared to dH₂O (6-fold) and PBS at pH 1.2 (26-fold). In vitro drug release studies showed that OA release from the SLNs was significantly increased within 300 min (p < 0.05) compared to the free drug. Similarly, AA release from the SLNs was significantly increased within 300 min (p < 0.05) compared to free AA. Conclusions: These results demonstrate that SLNs enhance OA and AA solubility and drug release, suggesting a promising strategy for improving oral bioavailability and therapeutic efficacy. Full article