Search Results (7,666)

Developing earth-abundant photocatalysts that operate efficiently under visible light remains a central challenge in sustainable aerobic oxidation chemistry. We synthesized a binuclear cobalt(II) structure (Co₂) in which two redox-active metal centers are bridged by a polypyridine scaffold to integrate light-harvesting and catalytic functions within a single low-nuclearity unit. The complex exhibits a strong absorption band below 450 nm, undergoes facile charge separation upon photoexcitation, and channels molecular oxygen (O₂) toward superoxide radical anion (O₂^•–) under blue-light irradiation. Spectroscopic and mechanistic studies indicate that the polypyridine framework governs photon capture and excited-state delocalization, whereas the proximal Co(II) sites mediate the subsequent single-electron transfer to O₂. Driven by this dual-site synergy, Co₂ selectively oxidizes a broad scope of thioethers to the corresponding sulfoxides in yields exceeding 95%, with no over-oxidation to sulfones detected. The catalyst retains its structural integrity over five successive runs without measurable activity loss. By confining complementary photophysical and redox functions within a discrete bimetallic unit, this work establishes a design strategy for noble-metal-free, visible-light-driven organic transformations. Full article

Marine rest raw materials are often undervalued or wasted despite their nutrient and bioactive composition. Calanus finmarchicus, harvested primarily for its omega-3-rich oil, yields a side-stream protein hydrolysate, C. finmarchicus hydrolysate (CFH), during commercial enzyme-assisted extraction. Although currently used as a feed ingredient, CFH contains low-molecular-weight peptides and free amino acids with potential for human health applications. This study evaluated the gastrointestinal stability of CFH and the impact of digestion on bioactivity using a static in vitro gastrointestinal digestion model. Fresh-frozen and freeze-dried C. finmarchicus were included to provide comparative data. Antioxidant capacity was measured by ferric reducing antioxidant power (FRAP) and oxygen radical absorbance capacity (ORAC) assays, and antidiabetic activity by dipeptidyl peptidase-IV (DPP-IV) and protein tyrosine phosphatase 1B (PTP1B) inhibition assays. The hydrolysate maintained its antioxidant capacity throughout digestion (at 165 min: FRAP: 27.5 ± 0.6 µmol TE/g dry weight (DW); ORAC: 411 ± 37 µmol TE/g DW). Digestion increased its DPP-IV inhibitory activity, with the inhibitory concentration (IC₅₀) decreased from 3.73 to 1.96 mg/mL (p ≥ 0.05). PTP1B inhibitors were nonselective and detected only at 0 and 30 min. These findings support our hypothesis that CFH may serve as a nutraceutical for humans and provide a rationale for subsequent in vivo studies. However, further identification of bioactive components and in vivo validation are warranted. Full article

The integration of advanced semiconductor architectures strictly mandates process thermal budgets below 200 °C, positioning low-temperature PECVD of silicon nitride (SiN_x) film as a critical layer. However, SiN_x film deposited at sub-200 °C inherently exhibits sluggish deposition kinetics and degraded spatial uniformity. To overcome these bottlenecks, this study systematically investigates the regulatory mechanisms of the NH₃ precursor within SiH₄/N₂-based plasmas under varying chamber pressures and substrate temperatures. The results show that the introduction of NH₃ at 2.1 Torr, leveraging its facile plasma dissociation, drastically enhances the deposition rate from 18.2 to 39.1 Å/s and improves thickness uniformity by 1.07%. Meanwhile, NH₃ supplies abundant highly reactive radicals that elevate the refractive index and reinforce compressive stress. Furthermore, film properties exhibit a higher sensitivity to pressure than to temperature, primarily due to the pronounced influence of pressure on plasma dynamics and collision frequencies, whereas the effect of temperature remains comparatively minor. This phenomenon is clearly demonstrated by the Si–H and N–H content. This study validates that operating at low chamber pressures maximizes the collision-free travel distance of SiN_x radicals, providing an optimized and quantified process window for high-volume manufacturing of low-temperature SiN_x film. Full article

The persistence of refractory organic pollutants (e.g., antibiotics) in aquatic environments necessitates efficient and sustainable remediation strategies. In this study, a circular economy approach was adopted to convert iron sludge into a value-added carbon residue (CR) composite via one-step co-pyrolysis. The resulting material was designed as dual-functional, enabling synergistic pollutant removal through adsorption and catalytic oxidation. Experimental results demonstrated that the CR composite effectively adsorbed and degraded organic pollutants. The primary adsorption sites were attributed to surface functional groups, porous structure, and electrostatic interactions. Meanwhile, iron species, surface functional groups, and persistent free radicals facilitated the generation of singlet oxygen (¹O₂) and hydroxyl radicals (·OH), which in turn promoted pollutant degradation. The CR/PDS system exhibited excellent performance in real wastewater remediation, which was attributed to the high interference resistance of ¹O₂. Furthermore, the application of CR did not pose any significant environmental risk in aqueous solutions. Taken together, these findings present a novel material for pollutant removal and provide a cost-effective strategy for the valorization of waste iron sludge. Full article

The aim of this study was to evaluate the effect of adding white mulberry (Morus alba L.) fruit to extruded corn snacks on their polyphenol profile, antioxidant properties, acetylcholinesterase (AChE) inhibitory activity and the preservation of phenolic compounds in an in vitro digestion model. Mixtures of corn grits with 0, 10, 15 and 20% dried mulberry fruit were extruded at temperatures of 100, 120 and 140 °C, and then the total polyphenol content (TPC) and antioxidant activity (IC₅₀ for DPPH) were determined. For selected samples (0%, 140—3E; 15% mulberry, 140—9E; mulberry—13E), further antioxidant tests (FRAP, CUPRAC, Fe²⁺ chelation) were performed, the phenolic compound profile (UHPLC) and AChE inhibition were assessed, and a two-step in vitro digestion was conducted. The addition of mulberry significantly increased TPC- and free-radical-scavenging capacity compared to the control sample, with snacks containing 15% mulberry extruded at 140 °C showing approximately a 3.5-fold higher TPC than the control, while dried mulberry fruit itself exhibited about a five-fold higher TPC than this enriched snack. Among the snacks, the most favorable DPPH-radical-scavenging effect was obtained for the variant with 20% mulberry at 120 °C (IC₅₀ = 0.176 mg/mL), whereas the mulberry fruit extract reached an IC₅₀ of 0.0926 mg/mL. In a two-step in vitro digestion model, the mulberry-enriched snack with 15% fruit retained 69.3% of its initial TPC after the gastric phase and 33.3% after the intestinal phase, compared with 55.0% and 20.0%, respectively, for the control snack, confirming a partial but meaningful preservation of phenolic compounds under simulated gastrointestinal conditions. UHPLC analysis confirmed that mulberry and the enriched snacks are a rich source of chlorogenic acids and their isomers, as well as quercetin and kaempferol glycosides, which largely survived the two-step in vitro digestion, despite an observed decrease in TPC after the gastric stage and a further reduction after the intestinal stage. At the same time, mulberry extract and mulberry-enriched snacks exhibited high antioxidant activity in all tests conducted and in vitro AChE inhibitory activity, suggesting that Morus alba L. fruit has the potential to be used as a natural functional ingredient in the production of gluten-free snacks with antioxidant and potentially neuroprotective properties. Full article

Satureja nepeta essential oil (EO) is gaining prominence for its multifaceted pharmacological and biotechnological potential. This study aimed to characterize its volatile profile and evaluate its functional capacity as an antioxidant, antibacterial, and antiproliferative agent. Gas Chromatography Mass Spectrometry (GC–MS) profiling was conducted to identify the volatile constituents of the EO. Antioxidant activity was assessed using DPPH, ABTS, TAC, and FRAP assays. Antibacterial activity was evaluated against Gram-positive and Gram-negative pathogens using disk diffusion and MIC determination. In silico molecular docking against bacterial DNA gyrase B was performed to explore potential mechanisms of action. Antiproliferative activity was assessed on the P3X63Ag8.653 myeloma cell line. Chemical profiling identified nine major constituents, dominated by pulegone (68.63%), menthol (6.64%), and cis-pulegol (2.04%). The EO demonstrated significant free radical-scavenging activity, particularly in the TAC assay (EC₅₀ = 3.747 ± 0.577 µg/mL). Antimicrobial evaluations revealed robust inhibitory effects, with Pseudomonas aeruginosa and Salmonella enterica exhibiting the highest susceptibility. In silico modeling corroborated these findings, identifying menthol as the lead ligand (ΔG = −6.09 kcal/mol), suggesting a synergistic mechanism of action. Notably, the EO displayed potent antiproliferative activity (LC₅₀ = 14.060 ± 1.364 µg/mL), falling well within the high-cytotoxicity threshold. Collectively, these findings underscore the pharmacological significance of S. nepeta EO as a potent reservoir of bioactive monoterpenes with antioxidant, antimicrobial, and anticancer properties, meriting further in vivo validation and mechanistic exploration toward its development as a therapeutic or nutraceutical candidate. Full article

Skin functionalities are instrumental in four main domains: protection, regulation, sensation, and support. However, excessive exposure to ultraviolet (UV) radiation can compromise skin integrity and, in turn, affect its functions, by generating reactive oxygen species (ROS). Aiming to protect skin from UV radiation, sunscreens incorporate UV filters and antioxidants that absorb/reflect UV rays and neutralise free radicals, respectively. Nevertheless, undesired side and ecological effects of conventional UV filters have spurred the search for safer alternatives. Among synthetic antioxidants, thioethers have attracted attention for their redox power and potential medicinal properties. In this context, a library of aminopyrimidine–arylthioether conjugates was synthesised and evaluated for their antioxidant, enzyme-inhibitory and antibacterial activities, as well as for their cytotoxicity in HaCaT cells and potential photoprotective properties. Among the aminopyrimidine-thioethers studied, compound C5 stood out for its antioxidant potential, exhibiting a value of 566.39 mM FeSO₄ equivalents per mM of the compound, while compound C2 showed the highest anti-enzymatic potential, inhibiting elastase (45.58%) and tyrosinase activities (34.66%). Regarding photoprotective activity, compound C13 reduced by 33.74% the ROS production induced by UV radiation exposure, at 100 μM, a non-cytotoxic concentration. Finally, compound C7 inhibited the growth of Staphylococcus epidermidis, Staphylococcus hominis and Cutibacterium acnes, at 30 μM. These preliminary results demonstrate that aminopyrimidine–arylthioethers constitute a new class of compounds warranting further investigation for skin protection. Compound C5 showed antioxidant activity in the FRAP assay, comparable to that of the positive control, BHT. Full article

Naphthalene (Nap) is widely distributed in the environment and has attracted concern due to its recalcitrance to biodegradation and acute toxic effects. Although several laccases can degrade naphthalene, it remains unclear whether laccase is involved in dioxygenation or ring fission of polycyclic aromatic hydrocarbons (PAHs). We demonstrated that laccase has a naphthalene dioxygenase function with a distinct joint approach to oxygen and the alternative regioselective ring-fission process. These results supplement the family of dioxygenase with laccase, a mild method for the ring opening of aromatics, and an operable scale-up application for remediation from PAH pollution and for regioselective oxygenation and ring opening. Full article

Aiming at severe soil secondary salinization, poor water retention and insufficient salt tolerance of conventional acrylic-based modifiers in arid and semi-arid regions of China, a poly(ethylene glycol) maleate citrate (PEGMC) crosslinking monomer was synthesized through esterification, and a dual covalent–hydrogen crosslinked P(PEGMC/AA) hydrogel was fabricated via free radical copolymerization with acrylic acid (AA). The hydrogel was characterized by NMR, FTIR, SEM, TGA and elemental mapping, while its binding mechanism with saline–alkali ions was elucidated through DFT calculations and molecular dynamics simulations. Its amelioration performance was evaluated through swelling, soil water retention, desalination and pot germination experiments. The hydrogel exhibited outstanding water absorbency, salt resistance and dry–wet cycling stability, with swelling ratios of 712 g/g in deionized water and 285 g/g in 0.9% NaCl solution, and remained 200 g/g after four dry–wet cycles. It enhanced soil water retention remarkably (over 93% after 72 h). At 0.30% dosage, soil salt content declined from 7.1 g/kg to 1.3 g/kg with desalination efficiency exceeding 80%, owing to porous physical adsorption and chemical chelation toward Na⁺, Ca²⁺ and Mg²⁺, with a binding energy of −136.936 kJ/mol. Pot tests revealed that crop germination rate rose from 19% (blank) to 75% under severe saline–alkali stress. Meanwhile, the hydrogel inhibited nutrient leaching and favored soil-water conservation. This work first incorporated PEGMC monomer into agricultural hydrogels to construct a stable dual crosslinked network, clarifying its synergistic mechanisms for salt fixation and water retention macroscopically and microscopically. It provides a promising functional material and theoretical basis for green, efficient in situ amelioration of dryland saline–alkali soil. Full article

Background/Objectives: Aerobic glycolysis is a standard mechanism that cancer cells use to support their anabolic processes. Lactate and proton production, byproducts of this LDHA-catalyzed transformation of pyruvate, may contribute to acidifying the tumor microenvironment and to repressing the cytotoxic activity of anti-tumor immune cells. Prostate cancer radiotherapy outcome could be diminished by cancer cell metabolism and immunosuppression. Methods: The tumor infiltrating lymphocyte (TIL) density was assessed in 110 prostate adenocarcinoma biopsies from patients treated with radical radiotherapy. Immunohistochemistry was performed to evaluate LDH5 expression by cancer cells (encoded by the LDHA gene). Results: Higher tumor stages (T3 and T4) were associated with lower TIL density (p = 0.02). Approximately half of the patients (51%) displayed strong LDH5 cancer cell expression, which was linked with advanced T-stage and higher Gleason scores (p = 0.05 and p = 0.01, respectively). High LDH5 expression was significantly correlated with low TIL density (p ≤ 0.0004). In univariate analysis, high LDH5 and low TIL density were associated with poor biochemical relapse-free survival (BRFS) (p ≤ 0.006). In multivariate analysis, TIL density, but not LDH5, was an independent predictor of BRFS (p = 0.03). Conclusions: LDH5 overexpression is associated with low tumor lymphocytic infiltration. Stratifying prostate carcinomas according to LDH5/TIL density identifies a group of patients with low TIL density and high LDH5 expression, who have a higher risk of tumor relapse. Targeting glycolysis to disrupt cancer cell metabolism offers an interesting research area for prostate cancer therapy. Full article

Lost circulation of wellbore fluids within fissured zones constitutes a primary factor contributing to increased non-productive time (NPT) and restricted rate of penetration (ROP). Conventional gel-based lost circulation materials (LCMs) inherently suffer from a tradeoff between pumpability and in situ fracture retention, and they lack a design methodology quantitatively correlated with drilling engineering parameters. In this study, a shear-responsive gel with a dual physically crosslinked network—combining hydrophobic association and Fe³⁺-mediated ionic coordination—was prepared through a single-step water-based radical polymerization process, utilizing commercially available monomers. By systematically tuning the hydrophobic monomer and Fe³⁺ contents, the gel’s fracture-sealing efficacy, autogenous healing ability, and shear rheological characteristics were evaluated, establishing a quantitative correlation between the critical shear rate and drilling parameters. The empirical data demonstrate that with an increase in the hydrophobic monomer dosage from 0.4 wt% to 1.2 wt%, the critical shear rate decreases from 22.5 s⁻¹ to 8.6 s⁻¹, exhibiting an exponential decay relationship. The optimized formulation, G0.8F0.5, demonstrates a low initial viscosity of 245 mPa·s under high shear conditions, which surges to 6180 mPa·s at a shear rate of 14.2 s⁻¹, achieving a thickening factor of 29.4. Upon incubation at 80 °C for a duration of 12 h, the formulated gel restores 94.9% of its mechanical tensile strength and 96.3% of its fracture strain, whereas the Fe³⁺-free control sample fails to heal. In dynamic plugging tests using a 3 mm fracture plate, G0.8F0.5 achieves a breakthrough pressure of 12.8 MPa with a minimal fluid loss of 98 mL. The LCM forms a monolithic gel block positioned at the middle-to-rear section of the fracture, outperforming conventional gel counterparts. Drilling hydraulics simulations reveal that deploying this gel reduces the annular equivalent circulating density (ECD) by 0.06 g/cm³. Furthermore, under idealized conditions, this approach is calculated to enhance the ROP by approximately 26%. The proposed molecular design of a shear-responsive, dual physically crosslinked network provides a viable technical pathway for quantitatively tailoring the shear-responsive properties of while-drilling LCMs. Full article

Momordica charantia L. is a medicinal plant rich in bioactive compounds, including steroidal glycosides, flavonoids, phenolics, triterpenoids, saponins, and polysaccharides, which exhibit antidiabetic, antioxidant, anti-inflammatory, hepatoprotective, and anticancer activities. This review summarizes its nutritional and phytochemical composition, green extraction technologies, molecular mechanisms, and industrial applications based on literature from Google Scholar, PubMed, Scopus, Web of Science, ScienceDirect, and other scientific databases. Ultrasound-assisted extraction is an efficient and eco-friendly method that provides higher recovery of bioactive compounds from M. charantia and improved bioavailability compared with enzyme-assisted, microwave-assisted, and conventional methods. The phytochemicals of M. charantia regulate oxidative stress, inflammation, lipid peroxidation, and glucose homeostasis. Studies show that its antidiabetic effects involve improved insulin sensitivity, enhanced glucose uptake, and inhibition of carbohydrate-digesting enzymes. These compounds also exhibit antioxidant activity through free radical scavenging and anti-inflammatory effects via inhibition of the NF-κB and MAPK pathways. M. charantia further demonstrates anticancer activity by inducing apoptosis, causing cell-cycle arrest, and downregulating proliferation pathways in several cancer cell lines, including MCF-7, HCT-116, HepG2, A549, and PANC-1. Beyond medicinal uses, it is applied in the food industry as a functional ingredient in products such as yogurt, cookies, pickles, bread, juice, oil, and beverages. Overall, M. charantia shows strong potential for therapeutic applications, including functional foods and pharmaceutical formulations targeting diabetes, inflammation, liver diseases, and cancer; however, further studies are needed to confirm its clinical efficacy. Full article

Fluid-loss additives play a critical role in maintaining the stability and filtration-control performance of water-based drilling fluids during deep and high-temperature drilling operations. However, the development of microgel-based additives with both exceptional thermal stability and strong salt tolerance remains a major challenge under harsh drilling conditions. In this study, a covalently micro-crosslinked anionic copolymer-based microgel (PAAN) was synthesized via free-radical copolymerization of acrylamide, 2-acrylamido-2-methylpropane sulfonic acid, and N-vinylpyrrolidone using N,N′-methylenebisacrylamide as the crosslinking agent. The chemical structure of PAAN is consistent with the design, with excellent thermal stability, and the starting temperature for thermal decomposition of polymer molecular chains is 297 °C. The weight average molecular weight of PAAN is 1.3396 × 10⁶ g/mol. After aging at 220 °C in the presence of 15 wt% NaCl, the PAAN-containing drilling fluid exhibited a high-temperature high-pressure filtration loss of only 15.6 mL. Even after prolonged aging for 168 h, the filtration loss remained at a relatively low level of 46.0 mL, indicating outstanding thermal stability and salt tolerance. Mechanistic analysis indicated that PAAN adsorbed onto bentonite surfaces through electrostatic interactions and hydrogen bonding, promoting clay-particle dispersion and colloidal stability. Moreover, the microgel network facilitated the formation of a compact and low-permeability filter cake, contributing to effective fluid-loss control under harsh conditions. These results demonstrate that microgel structural design is an effective strategy for improving the high-temperature and salt-resistant filtration-control performance of WBDFs, and PAAN shows strong potential for deep and ultra-deep drilling applications. Full article

Several sensitive bioactive substances are potent antioxidants that protect the skin from free radicals but are often rapidly degraded, limiting their effectiveness. Encapsulating these substances in liposomes improves their bioavailability and solubility and protects them from harmful environmental factors. The influence of liposomes as advanced lipid nanocarriers is increasing enormously due to their remarkable properties and protection of bioactive substances. For this reason, mango (Mangifera indica L.) peel extract (MPE), previously characterized and rich in various natural substances, including ellagic acid, gallic acid, and catechin, has been encapsulated in liposomes. The investigation focused on the impact of different liposome synthesis process parameters on their size, size distribution, stability, and encapsulation efficiency, and on in vitro release as a potential advanced MPE delivery system with suitable characteristics. An important study on the influence of the organic solvent used in liposome synthesis on the above properties is described. The thin lipid film hydration method using 5-mm glass beads and ethanol as an organic solvent was the most favorable method for synthesizing a stable and monodisperse lipid–MPE delivery system. MPE was successfully encapsulated in liposomes with the highest encapsulation efficiency of 53.7%. The sustained release of MPE from the liposomes was achieved, and the antibacterial properties of MPE, incorporated into the liposomes, were retained. For the first time, MPE has been encapsulated in liposomes, and with the remarkable results obtained, the extract represents a formulation with high added value that can be used in various fields, especially for the enrichment of different products such as cosmetic creams and lotion. Full article

The aim of this study was to determine the phenolic compound profile, antioxidant activity, antiproliferative activity, and toxicity of B. hindsiana. Ethanolic extractions of B. hindsiana leaves and stems were performed. The content of phenolic compounds was determined by the Folin–Ciocalteu method, while the phenolic compound profile was determined by UPLC-DAD. The antioxidant activity was evaluated using the DPPH, ABTS, ORAC, and FRAP methods. Antiproliferative activity was determined by the MTT method against HeLa, A549, and ARPE-19 cell lines. Acute toxicity was determined in Artemia salina. The results showed that the B. hindsiana leaf extract had the highest concentration of phenolic compounds, with quercetin-3-β-glucoside, rutin, and chlorogenic acid being the major compounds. Regarding antioxidant activity, the leaf extract showed a greater capacity (p < 0.05) to stabilize free radicals and reduce metals. For antiproliferative activity, the leaf extract also showed a greater capacity (p < 0.05) to inhibit the proliferation cancer cell lines. Finally, the B. hindsiana extracts presented an LC₅₀ value greater than 100 µg/mL in A. salina. Overall, the B. hindsiana extracts show promising biological potential, which may be associated with the phenolic compounds present, with low toxicity. This research is the first study reporting the phenolic compound profile and the leaf and stem biological activities from B. hindsiana. Full article