Search Results (1,711)

Foods rich in polyphenols are known to promote oral health by modifying the enamel pellicle. In doing so, they reduce bacterial adhesion, biofilm maturation, and erosion. The goal of this study was to screen local herbal drugs available in Central Europe for their potential suitability as part of a diet promoting oral health by targeting the initial stages of biofilm formation. To achieve this, an in situ study was conducted to evaluate the effects of the four polyphenol-rich herbal extracts of blackcurrant leaves, oak bark, horse chestnut leaves, and sweet chestnut leaves on early bacterial adhesion and biofilm formation on tooth enamel over an 8 h period. This research aimed to identify natural remedies that could support oral hygiene by targeting the initial stages of biofilm formation. Study Design and Experimental Procedures: Aqueous extracts were prepared by ultrasonic extraction. Eight human subjects wore bovine enamel slabs intraorally for 8 h. After 1 min of pellicle formation, the subjects rinsed with 8 mL of the extracts for 10 min, followed by intraoral exposure without food. An 8 h-exposure without rinse served as the negative control; 0.2% chlorhexidine gluconate (CHX) served as the positive control. After 8 h, bacterial adhesion and biofilm matrix formation on the enamel slabs were quantified ex vivo using DAPI/Concanavalin A staining and fluorescence microscopy. The LIVE/DEAD™ BacLight™ assay was used to assess bacterial viability. Statistical analysis was performed by the Mann–Whitney U test and Kruskal–Wallis test (p < 0.05), as well as the Bonferroni–Holm correction (p < 0.01). Results and Conclusions: The screened herbal drugs did not demonstrate a statistically significant impact on the number of adherent bacteria, suggesting that their mode of action may not directly interfere with bacterial adhesion mechanisms. However, all four extracts exhibited consistent trends toward reduced glucan formation and decreased bacterial viability. The observed inhibition of glucan formation indicates that these drugs may potentially target the enzymatic pathways responsible for polysaccharide synthesis. By disrupting glucan production, the structural integrity of the biofilm matrix might be compromised, which indirectly affects bacterial survival within the biofilm environment. Full article

Amino alcohols are a class of compounds bearing both amino and hydroxyl groups, ubiquitous in natural products and extensively utilized as key structural motifs in pharmaceuticals and functional materials. Owing to their structural diversity, inherent chirality, and high reactivity, they exhibit significant application value in the pharmaceutical field, materials industry, and organic synthesis. Compared with chemical synthesis, which suffers from limitations such as insufficient enantioselectivity, dependence on precious metal catalysts, and environmental concerns, biosynthesis offers core advantages of high stereoselectivity, mild reaction conditions, and environmental sustainability. This review systematically delineates the diverse applications of amino alcohols in the pharmaceutical field (e.g., anti-HIV, antimalarial, and antitumor drugs), materials industry (e.g., polymer modification and metal corrosion protection), and organic synthesis (e.g., chiral ligands and catalysts). Particular emphasis is placed on the biosynthetic strategies and pathways of representative amino alcohols, including ethanolamine, (2S,3R)-2-amino-1,3,4-butanetriol, (R)-3-amino-1-butanol, sphingosine, and metaraminol, as well as the metabolic engineering design principles and downstream processing technologies for amino alcohol biosynthesis. Although current biosynthetic approaches still face bottlenecks in enzyme catalytic efficiency, substrate tolerance, cofactor regeneration, product toxicity, and thermodynamic equilibrium, substantial improvements in synthetic efficiency and stereoselectivity have been achieved through protein engineering, metabolic engineering, in situ product removal, and multi-enzyme cascade optimization. This review aims to provide systematic theoretical references and technical insights for the green and efficient biomanufacturing of amino alcohols. Full article

The electrocatalytic nitrate reduction reaction (NO₃RR) enables sustainable ammonia synthesis from nitrate waste, yet its complex mechanism and severe competition from the hydrogen evolution reaction (HER) demand precise control over interfacial electronic structures. This review provides a mechanistic overview of interfacial electron engineering for NO₃RR via charge transfer, d-band center modulation, and d-p orbital coupling. We propose a reverse-engineering framework that starts from the three kinetic bottlenecks of NO₃RR (nitrate activation, *H supply, and intermediate poisoning) and back-extracts the required electronic effects (charge transfer, d-band shift, and d-p orbital coupling). From this perspective, we cover the construction of built-in electric fields (BIEFs) in heterojunctions, engineering atomic-scale active sites (e.g., single-atom and dual-atom catalysts), and exploiting hydrogen spillover and reverse spillover for cross-spatial proton delivery. Given that rational interfaces dynamically evolve under operating conditions, we highlight that in situ/operando characterization captures the dynamic restructuring of valence states, coordination environments, and morphologies, establishing clear structure–electron–activity relationships. Finally, we discuss key challenges and outline future directions, including machine learning-accelerated screening, dynamic interface regulation, and synergistic integration of multiple electronic effects. This review offers a comprehensive framework for interfacial electron engineering, guiding rational design of next-generation NO₃RR electrocatalysts. Full article

The sodium-coupled citrate transporter NaCT (SLC13A5) imports extracellular citrate into cells. In the CNS, SLC13A5 is described to be expressed predominantly in neurons. Cytosolic citrate levels rely on citrate generated in mitochondria and imported from other CNS cells, regulating intermediary metabolism and supplying acetyl-CoA for lipid synthesis and histone acetylation. Despite evidence for NaCT’s role in neurometabolic homeostasis, its transcriptional behavior across Alzheimer’s disease (AD) progression and across astrocyte subtypes remains uncharacterized at single-cell resolution. We analyzed single-nucleus RNA sequencing data from 1,378,211 nuclei across 84 donors in the Seattle Alzheimer’s Disease Brain Cell Atlas (SEA-AD) Middle Temporal Gyrus dataset to profile SLC13A5 and seven citrate metabolism genes across a continuous AD pseudoprogression score. SLC13A5 expression was restricted to astrocytes (~20% prevalence) and concentrated in the Astro 2 supertype (24.0%), a homeostatic subtype characterized by low C3 (1.6%) and CD44 (5.5%), which expanded with pseudoprogression (Spearman rho = +0.345, FDR < 0.001). The A1-reactive Astro 3 supertype, where SLC13A5 prevalence was 0.87%, declined concordantly (rho = −0.393). Opposing compositional and transcriptional forces produced apparent stability in overall SLC13A5 prevalence. SLC13A3 and ACO1 showed progressive donor-level declines correlating with Braak stage and Thal phase (rho range: −0.307 to −0.349, FDR < 0.01). APOE4 carriers exhibited lower SLC13A5 prevalence specifically within Astro 2 nuclei (median 17.6% vs. 25.9%; Wilcoxon p = 0.025), though this association did not survive multivariate regression. No difference in Astro 2 SLC13A5 expression was detected between cognitively resilient and expected-AD donors with equivalent high Braak burden (p = 0.888). Contrary to the prevailing description of NaCT as a neuronal transporter, SLC13A5 transcript in the SEA-AD MTG dataset was detected almost exclusively in astrocyte nuclei, concentrated in the homeostatic Astro 2 subtype, and maintained as this subtype expanded with advancing AD pathology. Because these are nuclear transcript measurements, they delimit where SLC13A5 mRNA is detectable rather than establishing the cellular site of NaCT protein or activity, which requires in situ validation. Full article

The Z-scheme Ag₂MoO₄/BiOCl heterojunction with oxygen vacancies was successfully fabricated at a low temperature via a simple in situ precipitation method. The morphological, structural, and optical characteristics of the Ag₂MoO₄/BiOCl heterojunction were systematically examined. The optimized synthesized Ag₂MoO₄/BiOCl heterojunction achieved a removal rate of 80.44% for ciprofloxacin within 180 min of simulated solar irradiation, which was 3.27 and 1.90 times higher than that of pure Ag₂MoO₄ and BiOCl, respectively. The fabricated Z-scheme heterojunction and oxygen vacancies optimize the electron transfer route, enhancing the separation efficiency of photogenerated electrons and holes. Moreover, the active species trapping experiments and ESR analyses demonstrated that holes were the primary reactive species involved in the photocatalytic process. It was hypothesized that the Ag₂MoO₄/BiOCl heterojunction adhered to a Z-scheme mechanism for charge transfer. The straightforward approach opened up novel avenues for the synthesis of efficient BiOCl-based photocatalysts aimed at environmental remediation. Full article

Oil pollution remains a persistent global environmental challenge due to the recalcitrance and toxicity of lipid-rich contaminants in terrestrial and aquatic ecosystems. Bacterial lipases (EC 3.1.1.3) play a pivotal role in the initial stages of bioremediation by catalysing the hydrolysis of complex lipids into more bioavailable intermediates, thereby facilitating downstream microbial degradation and mineralisation. This review critically examines the mechanistic basis of lipase-mediated hydrocarbon degradation, with emphasis on enzyme structure–function relationships, catalytic pathways, and regulation under environmentally relevant conditions. In addition to conventional applications in soil and wastewater bioremediation, emerging strategies involving immobilised enzymes, microbial consortia, and waste-derived substrates are evaluated for their effectiveness and scalability. Attention is given to advances in molecular and omics approaches, including metagenomics, transcriptomics, and proteomics, which have expanded the discovery of novel lipases but remain limited in their ability to predict in situ functionality. The review highlights the growing role of protein engineering and artificial intelligence in tailoring lipase properties; however, it also critically assesses current limitations, including insufficient experimental validation and challenges in translating computational predictions to complex environmental systems. Furthermore, integrating multi-omics data into quantitative and predictive frameworks is identified as a key future direction for improving bioremediation efficiency. Despite significant progress, major gaps persist in linking enzyme activity to real-world degradation performance and in developing standardized, scalable approaches. This review therefore provides a comprehensive and critical synthesis of current knowledge while identifying strategic research priorities required to advance bacterial lipases as robust tools for sustainable bioremediation of lipid-based pollutants. Full article

The Lantana genus, especially L. camara, has emerged as a potential yet underutilized lignocellulosic feedstock for various catalytic thermochemical conversion products and advanced carbon materials. This study reviews recent developments in the valorization of Lantana biomass to generate biofuels, bio-oil, syngas, and engineered biochar materials through pyrolysis, gasification, hydrothermal processing, and integrated biorefinery processes, in a critical manner. Particular focus will be on nanocomposite-modified, metal-doped biochar with catalytic elements such as ZSM-5, Fe₃O₄, TiO₂, and Ni-, Co-, and Zn-based oxides to enhance deoxygenation, catalytic cracking, tar reforming, pollutant remediation, and energy storage. Recent developments in catalyst synthesis techniques, such as impregnation, hydrothermal deposition, and in situ functionalization, are reviewed, along with characterization methods including BET, XRD, SEM/TEM, Raman spectroscopy, and XPS. The review further examines the impact of pore structure, surface chemistry, the presence of redox-active centers, and catalyst stability on product selectivity, syngas quality, and upgrading bio-oil performance. The effects of biochar on microbial immobilization, anaerobic digestion, and integrated biochemical conversion are discussed in detail, excluding thermochemical effects. The challenges of catalyst deactivation, biomass heterogeneities, scalability, techno-economic viability, and decentralized biomass logistics are also discussed. In summary, the development and implementation of catalytic reaction engineering, the design of nanocomposite biochar, and circular bioeconomy strategies have great potential to facilitate the conversion of invasive Lantana biomass into renewable fuels, multifunctional carbon materials, and environmentally friendly bioeconomy products. Full article

Iron-based Fischer–Tropsch synthesis (Fe-FTS) catalysts are central to coal-to-liquid (CTL) processes but suffer from rapid and complex deactivation under industrial conditions. This review critically examines the key deactivation mechanisms, including carbon/wax deposition, hydrothermal sintering, chemical poisoning (S, Cl, As), and mechanical attrition, and evaluates modern regeneration strategies. These strategies include supercritical fluid extraction for wax removal, controlled oxidative decoking, reductive reconstruction of active iron carbides (χ-Fe₅C₂), chemical de-poisoning, and structural upcycling. We also discuss emerging techniques such as non-thermal plasma and supercritical fluid-assisted reactivation. Finally, we highlight challenges in irreversible phase transformation, in -situ regeneration engineering, and economic feasibility, and outline future directions toward regeneration-friendly catalyst design and advanced syngas purification for a circular CTL economy. Full article

Lithium metal batteries (LMBs) incorporating solid-state electrolytes (SSEs) promise high energy density and safety, yet their practical deployment is hindered by poor interfacial stability between SSEs and lithium metal anodes. Here we show that a simple incorporation of LiBF₄ into the sulfohalide (Li₃SCl) framework forms a mixture Li₃SCl@LiBF₄ (LSC@BF) SSE via a two-step solid-state synthesis, preserving a high room-temperature ionic conductivity of 4.32 × 10⁻⁴ S cm⁻¹ with a low activation energy of 0.22 eV while fundamentally altering the interface. X-ray photoelectron spectroscopy and electron microscopy reveal that LiBF₄ promotes the in situ formation of a mechanically robust, LiF-rich solid-electrolyte interphase at the SSE|Li interface. This LiF-rich layer effectively suppresses lithium dendrite growth and stabilizes the interface, enabling symmetric Li|LSC@BF|Li cells to achieve stable lithium plating/stripping for over 800 h at 0.2 mA cm⁻². Cross-sectional post-mortem imaging confirms a dense, void-free interface without dendrite penetration. Our work demonstrates that LiBF₄ incorporation offers a simple, scalable strategy to simultaneously maintain high ionic conductivity and resolve interfacial instability in sulfohalide SSEs for high-performance LMBs. Full article

Electrochemical nitrate reduction reaction (eNO₃RR) has emerged as a promising alternative to the energy-intensive and carbon-intensive Haber–Bosch process for green ammonia synthesis. However, the intrinsic complexity of the eight-electron transfer pathway and inevitable competing side reactions limit the activity and selectivity of eNO₃RR. Maximizing the utilization of active sites and ensuring structural stability in electrocatalysts are essential for promoting surface proton-coupled electron transfer and improving Faradaic efficiency. Herein, we present a copper metal–organic framework (Cu-MOF)-derived electrocatalyst synthesized via in situ electrosynthesis on copper foam, using cetyltrimethylammonium bromide (CTAB) as a structure-directing agent, followed by electroreduction to produce a self-supported, nano-dendritic structure. This three-dimensional architecture exposes abundant active sites and facilitates electron transport, enabling efficient nitrate-to-ammonia conversion. The optimized CTAB-assisted electrode achieves an ammonia yield of 14.33 ± 0.61 mg h⁻¹ cm⁻² with a Faradaic efficiency of 90.95 ± 2.28% at −1.7 V versus Ag/AgCl. This study introduces a versatile design strategy for copper-based electrocatalysts that integrates structural stability with high activity, offering a sustainable approach for both ammonia production and nitrate remediation. Full article

A biological/synthetic hybrid graft copolymer was obtained by grafting poly(acrylic acid) (PAA, synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization) to amylopectin (AMP). The novel graft copolymer presents amphiphilic properties due to the inherent insolubility of AMP in water and was further utilized as a mediator for the synthesis of gold nanoparticles (AuNPs) following an environmentally friendly in situ procedure. The AMP-g-PAA copolymer formation by the interaction of the PAA end groups with the C(6)-OH groups on an AMP backbone was confirmed by Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) and 1D (proton (¹H NMR) and carbon (¹³C NMR) nuclear magnetic resonance, and Distortionless Enhancement by Polarization Transfer (DEPT)) and 2D (correlation (COSY) and heteronuclear single quantum coherence (HSQC)) spectroscopies. The calculated degree of substitution of 1.17 suggests that the grafting was done at one OH from the three in an anhydroglycosidic unit (AGU) (preferably at that in C6 position), with a mean grafting efficiency of 76%. Additional information obtained using thermogravimetric analysis shows that the thermal decomposition of AMP-g-PAA occurs in two steps, with a residual mass of ~16 wt% at 700 °C, higher than AMP or PAA, indicating increased thermal stability of the copolymer. Dynamic and electrophoretic light scattering (DLS and ELS) measurements were used to determine the hydrodynamic size and ionic charge of the AMP-g-PAA self-assemblies in aqueous solution as well as their stability. The AMP-g-PAA was subsequently tested as a reducing agent in the environmentally friendly synthesis of AuNPs in aqueous solution, at different incubation temperatures, reaction duration, and inorganic/polymer weight ratios. The development of the surface plasmon resonance band of AuNPs, observed in UV–vis spectra, was consistently monitored over the reaction time. DLS analysis indicated time-dependent changes in the AuNPs’ particle size distributions, while scanning transmission electron microscopy confirmed that the AuNPs formed at the inorganic/polymer weight ratio of 0.36 and at 60 °C were predominantly well-dispersed, spherical-shaped nanoparticles. The AuNPs synthesized in situ within the copolymer matrix did not introduce additional cytotoxicity compared to the parent copolymer alone, with the composites representing a promising safety baseline for further investigation in biomedical applications. Full article

MXenes, a rapidly expanding family of two-dimensional transition-metal carbides and nitrides, are increasingly viewed as strong candidates for defense-oriented multifunctional systems because they combine metallic conductivity, surface tunability, mechanical flexibility, and solution processability within a lightweight platform. Unlike conventional metals, ceramics, and semiconductors, which usually optimize one or two parameters at the expense of density, brittleness, or integration compatibility, MXenes offer a rare opportunity to coordinate electromagnetic, mechanical, thermal, and sensing functions within one material family. Different from existing reviews that focus on laboratory-level record performance or single-function optimization, this review presents an innovative deployment-oriented perspective and fills the research gap of systematic military-oriented evaluation for MXenes. In this review, we examine MXenes from a deployment-oriented perspective rather than through isolated record values. We first summarize their formation chemistry and major synthesis routes, including HF and in-situ HF etching, bifluoride and alkaline methods, molten-salt strategies, electrochemical approaches, and precursor-free chemical vapor deposition. We then discuss the principal levers of property regulation, focusing on composition design, surface-termination control, and heterostructure engineering, and show how these strategies shape the performance envelopes relevant to shielding, stealth, impact response, energy storage, and sensing. This review constructs a full-chain analytical framework from synthesis, property regulation to military application and deployment challenges for the first time. Finally, we identify the main barriers to translation, especially manufacturing inconsistency, termination heterogeneity, oxidation and interfacial degradation, and limited application-level validation, and outline the most realistic paths toward deployable defense technologies. Full article

Hydrogen peroxide (H₂O₂) is a key reactive oxygen species involved in both cellular signaling and oxidative stress, making its reliable detection essential in biological and environmental systems. Electrochemical sensing has emerged as a promising approach for H₂O₂ monitoring due to its high sensitivity, rapid response, and suitability for in situ analysis. This review provides a comprehensive overview of nanostructured metal oxide electrodes for non-enzymatic electrochemical detection of H₂O₂. The effects of material composition, nanostructure morphology, and synthesis strategies (particularly hydrothermal methods) on sensor performance are critically discussed. Special attention is given to our previously reported studies, enabling a consistent comparison of structure–property relationships under similar experimental conditions. Furthermore, the application of these sensors in plant stress analysis is examined, including both the monitoring of oxidative stress and the evaluation of stress mitigation strategies using metal oxide nanoparticles. The role of nanoparticles as reactive oxygen species scavengers and enhancers of plant antioxidant systems is highlighted, demonstrating their ability to reduce H₂O₂ levels and improve plant physiological status under adverse environmental conditions. Overall, this work emphasizes the dual functionality of nanostructured materials as both sensing platforms and active agents for stress mitigation, highlighting their potential in agricultural and environmental applications. Full article

The direct synthesis of dimethyl carbonate (DMC) from methanol and CO₂ requires the use of a dehydrating agent such as 2-cyanopyridine (2-CP) to overcome thermodynamic limitations, alongside controlled catalyst surfaces to limit competing side reactions. In this study, mesostructured CeO₂ catalysts were synthesized via a nanocasting approach using SBA-15 as a hard template. The specific impact of the precursor infiltration method and the final thermal treatment on catalytic performance were evaluated. While a one-step precursor infiltration route yielded the most ordered mesostructure after template removal, the final calcination step emerged as the dominant variable governing catalyst activity and selectivity. Textural analysis confirmed that calcination preserved the interconnected nanorod morphology with only a minor decrease in specific surface area. Temperature-programmed desorption (TPD) revealed that the thermal treatment induced a redistribution of surface acid-base sites, specifically increasing the ratio of medium-strength basic to acidic sites. In situ DRIFTS demonstrated that this tailored surface chemistry facilitated CO₂ activation, promoted the formation of bidentate carbonates, and favored the monomethyl carbonate (MMC) intermediate formation. Consequently, the calcined CeO₂-OS catalyst achieved 74% methanol conversion and 91% DMC yield at 120 °C and 5 MPa, outperforming its uncalcined counterpart by suppressing 2-CP-related secondary reactions. Full article

Magnetic graphene composites have emerged as a frontier material platform, offering designable properties and multifunctional integration across environmental, biomedical, electromagnetic, and energy applications. Despite extensive research, a coherent knowledge framework that systematically connects synthesis, structure, property, and application remains lacking. This review addresses this gap by establishing an integrated “synthesis–structure–property–application” design paradigm. We first propose a four-tier evolutionary framework for synthesis strategies, tracing the progression from modular in-situ assembly, substrate-guided single-component in-situ formation, and synchronous in-situ formation to molecular-scale precursor co-conversion. This framework reveals the causative relationships between synthesis pathways and microstructures, and culminates in an application-oriented synthesis decision-making tool that enables rational strategy selection. Building on this synthesis foundation, we systematically analyze three core structural regulation strategies—interface engineering, defect and doping engineering, and hierarchical structure construction—demonstrating how they function as synergistic “control knobs” for tailoring composite properties. Through detailed case studies across four application domains, we quantitatively show how targeted structural design drives performance breakthroughs: enabling high-capacity and selective pollutant removal in environmental remediation; constructing intelligent theranostic platforms in biomedicine; reconciling the “thin, lightweight, broadband, and strong” paradox in electromagnetic interference (EMI) shielding; and ensuring long-cycle stability of high-capacity electrodes in energy storage. Finally, we summarize the paradigm shift from “functional combination” to “performance synergy” and outline future directions, including dynamic intelligent systems, sustainable manufacturing, and data-driven design. This review provides a systematic theoretical framework and practical roadmap for the rational design and on-demand fabrication of MGCs, marking the field’s transition from empirical exploration toward predictive, design-driven science. Full article