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Hot-filament chemical vapor deposition (HFCVD) facilitates the realization of industrial mass production owing to its simple synthesis device, facile control of process conditions, and low preparation cost. Reactive pressure is one of the deposition parameters that exert a profound influence on the growth of HFCVD diamond films on polycrystalline diamond (PCD) substrates, primarily affecting the growth rate and grain size of the deposited diamond coating. A univariate experimental approach was employed to investigate the effects of reactive pressure (2 kPa, 3 kPa, 4 kPa, 5 kPa) on the properties of as-deposited diamond films. The results show that with the increase in reactive pressure, the growth rate increased first and then decreased, peaking at 5.366 μm/h at 3 kPa. The fractal dimension and grain size follow a similar variation trend, both decreasing first and then increasing. The grain size drops to 15.8 nm when the reactive pressure is 3 kPa, at which point the adhesive strength of the film is maximized. This phenomenon can be attributed to the fact that excessively low reactive pressure extends the mean free path of particles and active species, endowing them with higher kinetic energy and reducing collision-induced energy loss. This in turn significantly promotes diamond nucleation, secondary nucleation and grain refinement, thus facilitating the growth of nanocrystalline diamond. In contrast, an excessively high pressure yields the opposite effect, inhibiting nucleation and promoting grain coarsening. Full article

Advances in dental material science over recent decades have significantly improved the mechanical, physical, esthetic, and adhesive properties of restorative systems. As clinical performance and durability have reached high standards, research has progressively shifted from purely mechanical replacement toward the development of bioactive materials capable of interacting beneficially with biological tissues. Rather than functioning solely as passive restoratives, contemporary materials are increasingly designed to contribute to disease prevention and tissue repair. Bioactive functionality encompasses both bioprotective and biopromotive effects, including antimicrobial activity, reinforcement of the dental substrate, promotion of remineralization, modulation of inflammatory responses, and stimulation of regenerative pathways. In this context, the surface pre-reacted glass ionomer (S-PRG) particle has emerged as a multifunctional bioactive technology. Its unique three-layer structure enables sustained release of multiple ions, fluoride, strontium, boron, sodium, silicate, and aluminum, associated with mineralization, biofilm inhibition, inflammatory regulation, and activation of cellular signaling pathways. An integrative review was conducted through a literature search in PubMed, SciELO and Scopus using the descriptors “Surface-reaction-type prereacted glass ionomer” and “S-PRG.” Experimental studies evaluating antimicrobial, anti-inflammatory, remineralizing, cellular, or regenerative effects of S-PRG-containing materials were considered eligible. A total of 49 studies met the inclusion criteria and were analyzed through descriptive synthesis. The available evidence indicates that the biological activity of S-PRG-containing materials extends beyond caries prevention, including modulation of inflammatory responses, enhancement of mineralization processes, and stimulation of cellular pathways related to tissue repair. These findings highlight the potential of S-PRG technology as a promising strategy for the development of restorative materials with regenerative and preventive properties. Full article

Electrocatalytic seawater splitting is an ideal strategy for the large-scale production of green hydrogen. Compared to scarce freshwater, oceanic seawater electrolysis represents a game-changer for the hydrogen economy. Herein, we report a cost-effective one-step synthesis of binder-free, self-supported 3D nickel–manganese–cobalt (NiMnCo) coatings on titanium (Ti) substrates and evaluated their electrocatalytic performance for the hydrogen evolution reactions (HERs) in alkaline media (1.0 M KOH), simulated seawater (SSW, 1.0 M KOH + 0.5 M NaCl) and alkaline natural seawater (ASW, 1.0 M KOH + natural seawater). These ternary coatings were electrodeposited on Ti substrates using an electrochemical deposition method via a dynamic hydrogen bubble template (DHBT) technique. The optimized ternary NiMnCo/Ti-2 electrocatalyst exhibited an enhanced HER activity in both alkaline and seawater media, achieving an ultra-low overpotential of 29, 59 and 66 mV to reach the benchmark current density of 10 mA cm⁻² in SSW, ASW and 1.0 M KOH, respectively. This efficient 3D ternary NiMnCo/Ti-2 electrocatalyst demonstrated stable long-term performance at a constant potential of −0.23 V (vs. RHE) and a constant current density of 10 mA cm⁻² for 50 h without any significant degradation. Furthermore, it exhibited long-term stability in alkaline electrolyte and simulated seawater during multi-step chronopotentiometric testing at variable current densities from 20 mA cm⁻² to 100 mA cm⁻² for 18 h. This superior performance can be attributed to its unique intermetallic structure and multi-component composition, which provides good Cl⁻ resistance, electrochemical stability and synergistic effects among its constituents. Therefore, the optimized NiMnCo/Ti-2 electrocatalyst is a promising candidate for practical seawater electrolysis aiming at green hydrogen production. Full article

The NiCo₂O₄/nickel cobalt sulfide (NiCoS) electrode was constructed on a nickel foam (NF) substrate using a combination of hydrothermal synthesis and constant potential electrodeposition. The NiCo₂O₄ prepared via an in situ hydrothermal method followed by calcination served as an intermediate layer, providing structural support and abundant active sites for the subsequent electrodeposition of the NiCoS top layer. The NiCoS loading amount was optimized by adjusting the deposition time. The optimized NiCo₂O₄/NiCoS electrode delivered an areal specific capacitance (Cs) of 6.94 F cm⁻² at a discharge current density of 2 mA cm⁻² with a coulombic efficiency of 98.85%. It retained 64.52% of its initial capacitance as the current density increased from 2 to 80 mA cm⁻² and exhibited an equivalent series resistance (R_ESR) of 1.06 Ω cm⁻². Furthermore, the NiCo₂O₄/NiCoS electrode retained 88.24% of its initial capacitance after 700 charge/discharge cycles, eventually stabilizing at 81.25% within 4000 cycles. Full article

6(5H)-phenanthridinone derivatives, as an important class of alkaloids, have broad application value in drug development and functional material synthesis. In this study, a nickel-catalyzed synthetic strategy was developed, using 2-bromobenzamide compounds as starting materials. Through an intermolecular cyclization reaction, a series of 6(5H)-phenanthridinone derivatives bearing amide substituents was efficiently constructed. The optimal reaction system was identified: Ni(acac)₂/Zn as the catalyst, PCy₃ as the ligand, toluene as the solvent, Cs₂CO₃ as the base, under an argon atmosphere at 150 °C for 12 h. The target products were obtained in yields up to 88%. Further substrate scope exploration demonstrated the excellent generality of this method, successfully synthesizing 21 derivatives with various substitution patterns, achieving yields ranging from 51% to 92%, and showing good compatibility with multiple functional groups such as alkyl, aryl, and heterocyclic moieties. Importantly, the reaction remained stable during gram-scale experiments, successfully yielding the desired compound at 85%. This work not only provides an approach for the precise construction of the 6(5H)-phenanthridinone framework but also opens an efficient pathway for the controlled synthesis of amide-substituted derivatives. Full article

Imine reductases (IREDs) have emerged as valuable biocatalysts for the asymmetric synthesis of chiral amines, key intermediates in numerous active pharmaceutical ingredients. Their ability to operate under mild reaction conditions with high chemo- and stereoselectivity provides an attractive alternative to conventional metal-catalyzed or chemical reduction processes. However, the broader industrial application of wild-type IREDs is often constrained by their limited substrate scope and moderate catalytic efficiency. Recent advances in biocatalysis have demonstrated that engineered IREDs can catalyze the reduction of a wide range of natural and non-natural imines, significantly expanding their applicability in pharmaceutical and fine chemical synthesis. In parallel, enzyme immobilization strategies have proven highly effective for improving operational stability, facilitating enzyme reuse, and enabling continuous flow biocatalytic processes. Efficient cofactor regeneration systems have further enhanced the practical implementation of IRED-based transformations. Advances in protein engineering, including structure-guided design, semi-rational mutagenesis, and directed evolution, have generated enzyme variants with improved catalytic activity, stereoselectivity, and substrate tolerance. The integration of high-throughput screening technologies and machine-learning-assisted enzyme design has further accelerated the discovery and optimization of efficient IRED biocatalysts. This review summarizes recent progress in the protein engineering and immobilization of IREDs and discusses future perspectives for their industrial application. Full article

Growth, reproduction, and survival are fundamental biological priorities that animals balance by evaluating dietary cues. Cholesterol occupies a unique position among nutrients, serving both as a structural component of cellular membranes and as a precursor for steroid hormones, yet its regulation differs fundamentally across taxa. In mammals, cholesterol availability is buffered by endogenous synthesis and post-ingestive metabolic control. In contrast, insects have evolutionarily lost sterol biosynthesis and are therefore sterol auxotrophs that rely entirely on dietary sources. Here, we synthesize current understanding of cholesterol biology in Drosophila melanogaster, with a focus on sterol auxotrophy, life-stage–specific allocation, and endocrine and lifespan outcomes in a comparative framework. We highlight cholesterol not only as a metabolic substrate but also as a sensory-encoded nutrient that shapes feeding behavior. We further examine how lipophorin (Lpp)-mediated transport, Niemann–Pick type C proteins, ATP-binding cassette transporters, and the nuclear receptor DHR96 coordinate systemic sterol distribution and endocrine output in the absence of endogenous synthesis. By integrating these mechanisms across development, we illustrate how cholesterol availability governs larval growth, ecdysteroid production, adult reproduction, neural function, and lifespan through coupled endocrine and nutrient-signaling networks. This review positions cholesterol as a multifunctional signal linking sensory perception, metabolic regulation, and life-history strategy in sterol-auxotrophic insects, offering a framework for understanding how evolutionary loss of biosynthetic capacity reshapes nutrient sensing and homeostatic control. Full article

The large-scale production of microbial bioplastics remains limited by high production costs, reliance on refined substrates, and inefficient utilization of agro-industrial residues. Although sugarcane bagasse has been explored as a carbon source for polyhydroxyalkanoate production, studies have predominantly focused on poly (3-hydroxybutyrate) (PHB), with limited reports on copolymer synthesis from pentose-rich lignocellulosic streams. In this study, a newly isolated Bacillus sp. HLI02 was employed for the biosynthesis of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), using pentosan-rich sugarcane bagasse hydrolysate as an inexpensive and sustainable carbon source. Fermentation parameters were systematically optimized at different pH and temperature, and the strain demonstrated efficient conversion of xylose-rich hydrolysate into PHBV without the requirement for external nutrient supplementation. Under optimized conditions (pH 7.0, 37 °C, and C/N ratio of 40), a maximum PHBV yield of 2 g/L, corresponding to 59.5% of cell dry weight, was achieved. Structural and compositional analyses using Fourier transform infrared spectroscopy (FTIR), gel permeation chromatography (GPC), and ¹H and ¹³C nuclear magnetic resonance (NMR) spectroscopy confirmed successful PHBV copolymer formation with well-defined structural characteristics. Thermal analysis revealed a decomposition temperature of 166 °C, indicating good thermal stability. The produced PHBV further exhibited favourable biocompatibility and biodegradability, supporting its potential applicability in sustainable packaging and related sectors. This work demonstrates the effective conversion of hemicellulosic sugarcane bagasse hydrolysate into PHBV using a newly isolated Bacillus strain, highlighting an underexplored route for copolymer production from agro-waste–derived C5 sugars. By integrating low-cost feedstock utilization with process optimization and comprehensive polymer characterization, this study contributes to the development of economically viable and sustainable bio-based polymer production strategies. Full article

In this study, a metal-free approach was developed for the synthesis of isocoumarin frameworks by exploiting the reactivity between ortho-carboxylate-ester-substituted diaryliodonium salts and acetoacetates. This transformation involved the sequential C-arylation of an activated methylene substrate, followed by in situ enolization and intramolecular lactonization to construct an isocoumarin core. Under operationally simple conditions, a range of diaryliodonium salts and acetoacetate esters were employed to afford structurally diverse isocoumarins. The resulting products contained synthetically valuable functional groups, including halogen, nitro, carboxylate ester, and azide substituents, which facilitated further derivatization and extension toward complex architectures and potential applications. Subsequent transformation of the selected isocoumarin products enabled the synthesis of furo[3,4-c]isochromene-1,5-dione motifs, which are observed in several natural products. Full article

The development of sustainable and environmentally benign N-methylation methodologies is essential for enhancing sustainable synthetic practice in pharmaceutical manufacturing. In this study, we demonstrate that microwave heating (MWH) markedly enhanced the efficiency of cobalt-catalyzed N-methylation using methanol or methanol-d₄ as green C1 sources. Compared with conventional heating (CH), MWH enabled highly efficient syntheses of key pharmaceutical intermediates—including 6-dimethylamino-1-hexanol, imipramine hydrochloride, and butenafine hydrochloride—under milder conditions and shorter reaction times and without generating hazardous halogen-containing waste. UV–vis spectroscopic analysis revealed that MWH accelerated the transformation of Co(acac)₂ into catalytically active Co species by approximately four-fold, providing a mechanistic basis for the enhanced reactivity. We hypothesized that this effect was caused by the selective microwave heating of the catalyst, which in turn promoted the rapid generation of catalytically active species. Notably, MWH also significantly improved the N-trideuteromethylation of amines using methanol-d₄, achieving a 95% yield for imipramine-d₃ hydrochloride versus 32% under CH. Molecular dynamics simulations indicated that methanol-d₄ exhibited slower dipole relaxation and enhanced cluster fragmentation under microwave fields, improving catalyst–substrate contact, while kinetic isotope effects stabilized reactive intermediates. These synergistic effects account for the pronounced microwave promotion observed in deuterated systems. Overall, the combination of MWH and cobalt catalysis offers an energy-efficient, waste-minimizing, and environmentally benign strategy for the scalable synthesis of both methylated and deuterated amines. Full article

Efficient microbial assimilation of high-concentration ammonium nitrogen and its conversion into value-added bioproducts represent a pivotal yet underexplored strategy for sustainable nitrogen management. Here, we report a newly isolated Bacillus velezensis strain, GY1, with a robust intrinsic capacity for simultaneous NH₄⁺-N assimilation and γ-polyglutamic acid (γ-PGA) biosynthesis. Under optimized conditions (37 °C, pH 7.0, C/N = 12:1), GY1 achieved 76.5% removal of ammonium nitrogen (400 mg/L) with negligible nitrite accumulation (<0.02 mg/L), indicating assimilation rather than nitrification. Transcriptomic analysis revealed a coordinated metabolic flux wherein the glutamine synthetase - glutamate synthase pathway GS-GOGAT pathway supplies glutamate for γ-PGA synthesis, while polymerization further facilitates ammonium sequestration via electrostatic interactions. GY1 produced up to 612.8 mg/L γ-PGA, and genetic overexpression of capB synchronized these pathways, enhancing both ammonium assimilation (87.4%) and γ-PGA yield (843.9 mg/L). Notably, this metabolic coupling remained resilient in complex substrates, achieving 68.8% ammonium removal and 220.7 mg/L γ-PGA production in untreated biogas slurry. Together, these findings establish GY1 as a metabolically robust platform linking nitrogen assimilation with biopolymer synthesis, offering a mechanistic framework for circular nitrogen economies. Full article

The growing volume of fiber-reinforced polymer composite waste creates an urgent need for efficient recycling technologies. While solvolysis effectively breaks down thermoset matrices for fiber reinforcement recovery, the process generates hydrocarbon-rich liquid by-products that require further management. This study validates the use of these liquid recycling streams—derived from the solvolysis of unsaturated polyester and epoxy resins—as sustainable carbon precursors for the growth of carbon nanomaterials. Synthesis was performed via catalytic chemical vapor deposition (CVD) at 850 °C using iron nanoparticles impregnated on a zeolite substrate. Morphological analysis confirmed the production of one-dimensional nanostructures (carbon nanotubes/nanofibers), with average diameters below 100 nm. Raman spectroscopy revealed a high degree of graphitization, with I_D/I_G ratios ranging from 0.25 to 0.58, which is comparable to structures synthesized from conventional precursors. Thermogravimetric analysis (TGA) demonstrated high thermal stability and carbon purity reaching up to 90.3%. These findings demonstrate a viable upcycling pathway that enhances the economic attractiveness of composite recycling by transforming waste into advanced nanomaterials. Full article

Whole-cell biocatalysis presents a sustainable and efficient approach for the selective reduction in α,β-unsaturated bonds in flavonoid derivatives. This study investigates the capability of yeast strains from the Yarrowia clade to catalyze the chemoselective reduction of 4′-methoxychalcone (1a) to its dihydro derivative. All tested strains exhibited similarly high hydrogenation activity, indicating a broadly conserved enoate reductase function within the clade. Among them, Yarrowia lipolytica KCh 71, previously reported and well characterized in the literature, was selected for preparative-scale transformation of a diverse series of synthetic methoxychalcones bearing additional methoxy groups in positions C-2, C-3, C-4, C-5, and C-6 of ring B. All derivatives were effectively converted into the corresponding dihydrochalcones, with yields ranging from 62% to 92%. Among the tested derivatives, the 2′,4′,6′-trimethoxy chalcone (7a) did not undergo biotransformation under our conditions, whereas mono- and di-methoxy derivatives (2a–6a) were efficiently reduced. These results confirm the broad substrate tolerance, high efficiency, and potential scalability of Y. lipolytica KCh 71, supporting its potential as a whole-cell biocatalyst for the sustainable synthesis of bioactive dihydrochalcones. The consistently high hydrogenation activity observed across 21 tested strains suggests the involvement of evolutionarily conserved enoate reductases. Bioinformatic analysis supports that the Yarrowia clade possesses a robust complement of Old Yellow Enzymes (OYE), providing a reliable enzymatic basis for the observed chemoselective reductions. All Yarrowia tested strains showed the same general transformation type, although the extent and rate of conversion differed among strains, and Y. lipolytica KCh 71 was one of the most tolerant. The broad reduction in α,β-unsaturated chalcones is consistent with the action of flavoenzymatic ene-reductases, particularly Old Yellow Enzyme (OYE)–like reductases. Bioinformatic analysis of Yarrowia genomes reveals putative OYE homologs, supporting this mechanistic interpretation, although the specific enzymes were not identified in this study. Full article

In this study, the in situ solvothermal synthesis of a copper-based metal–organic framework (Cu-BTC MOF) into two porous ceramic substrates with a 10 cm diameter and 2 cm thickness was reported. X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, diffuse reflectance spectroscopy (DRS), Tauc plot analysis, optical microscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were the techniques that were utilized to verify the formation and incorporation of the MOF into ceramics (two samples, with different SiO₂ particles; 500 µm (Ceramic 1), and 150 µm (Ceramic 2)). The synthesized Cu-MOF exhibited a crystalline structure. Both the composites and the Cu-MOF exhibited visible-light absorption, with optical band gaps of 2.5 eV and 2.4 eV, respectively, as determined by DRS. TEM images demonstrated that crystalline MOF domains were successfully included inside the ceramics. Methyl orange (MO), Congo red (CR), and methylene blue (MB) were used to assess the composites’ ability to remove dyes. Catalytic hydrogenation, powered by in situ hydrogen production from NaBH₄ hydrolysis, demonstrated high removal efficiencies of 91–97% after 60 min. Adsorption, on the other hand, was ineffective. Despite undergoing four consecutive cycles without performance degradation, the materials demonstrated remarkable recyclability. Cu-MOF@ceramic composites are effective, durable, and practically applicable for improved wastewater treatment. Full article

D-allulose is a rare low-calorie sugar with considerable health benefits and industrial potential. Compared with chemical synthesis and free enzyme catalysis, microbial production using engineered cells offers a low-cost and highly stable solution. Therefore, we investigated the reaction pathway underlying the synthesis of D-allulose from D-glucose. Specifically, the enhancement of glucose isomerase-catalyzed reactions and their role in D-allulose synthesis were evaluated. First, a mutant strain with significantly increased glucose isomerase from Anoxybacillus kamchatkensis G10 (AGGI) expression was obtained through ultraviolet mutagenesis combined with high-throughput flow cytometry. A 4.55-fold increase in AGGI activity and a D-fructose conversion yield of 51.2% were obtained. A dual-enzyme pathway was subsequently constructed by co-expressing AGGI and D-allulose 3-epimerase (DAEase) in the optimized host. After balancing the catalytic requirements of both enzymes through optimization of reaction conditions, CRISPR-associated transposase was employed to efficiently integrate the glucose transporter gene galP into the genome, further enhancing substrate supply. The final engineered Escherichia coli strain achieved a D-allulose conversion rate of 15% from 20 g/L D-glucose. This demonstrates the crucial role of glucose isomerase in microbial D-allulose production and advances the optimization and development of D-allulose synthesis strategies using D-glucose as a substrate. Full article