Precisely constructing orbital coupling-modulated iron dinuclear site for enhanced catalytic ozonation performance.

The advancement of atomically precise dinuclear heterogeneous catalysts holds great potential in achieving efficient catalytic ozonation performance and contributes to the understanding of synergy mechanisms during reaction conditions. Herein, we demonstrate a "ship-in-a-bottle and pyrolysis" strategy that utilizes Fe2(CO)9 dinuclear-cluster to precisely construct Fe2 site, consisting of two Fe1-N3 units connected by Fe-Fe bonds and firmly bonded to N-doped carbon. Systematic characterizations and theoretical modeling reveal that the Fe-Fe coordination motif markedly reduced the devotion of the antibonding state in the Fe-O bond because of the strong orbital coupling interaction of dual Fe d-d orbitals. This facilitates O-O covalent bond cleavage of O3 and enhances binding strength with reaction intermediates (atomic oxygen species; *O and *OO), thus boosting catalytic ozonation performance. As a result, Fe dinuclear site catalyst exhibits 100% ozonation efficiency for CH3SH elimination, outperforming commercial MnO2 catalysts by 1,200-fold. This research provides insights into the atomic-level structure-activity relationship of ozonation catalysts and extends the use of dinuclear catalysts in catalytic ozonation and beyond.

Engineering of Graphitic Carbon Nitride (g-C3N4) Based Photocatalysts for Atmospheric Protection: Modification Strategies, Recent Progress, and Application Challenges.

Graphitic carbon nitride (g-C3N4) is a prominent photocatalyst that has attracted substantial interest in the field of photocatalytic environmental remediation due to the low cost of fabrication, robust chemical structure, adaptable and tunable energy bandgaps, superior photoelectrochemical properties, cost-effective feedstocks, and distinctive framework. Nonetheless, the practical application of bulk g-C3N4 in the photocatalysis field is limited by the fast recombination of photogenerated e--h+ pairs, insufficient surface-active sites, and restricted redox capacity. Consequently, a great deal of research has been devoted to solving these scientific challenges for large-scale applications. This review concisely presents the latest advancements in g-C3N4-based photocatalyst modification strategies, and offers a comprehensive analysis of the benefits and preparation techniques for each strategy. It aims to articulate the complex relationship between theory, microstructure, and activities of g-C3N4-based photocatalysts for atmospheric protection. Finally, both the challenges and opportunities for the development of g-C3N4-based photocatalysts are highlighted. It is highly believed that this special review will provide new insight into the synthesis, modification, and broadening of g-C3N4-based photocatalysts for atmospheric protection.

Optimization of Carbon-Defect Engineering to Boost Catalytic Ozonation Efficiency of Single Fe─N4 Coordination Motif.

Carbon-defect engineering in single-atom metal-nitrogen-carbon (M─N─C) catalysts by straightforward and robust strategy, enhancing their catalytic activity for volatile organic compounds, and uncovering the carbon vacancy-catalytic activity relationship are meaningful but challenging. In this study, an iron-nitrogen-carbon (Fe─N─C) catalyst is intentionally designed through a carbon-thermal-diffusion strategy, exposing extensively the carbon-defective Fe─N4 sites within a micro-mesoporous carbon matrix. The optimization of Fe─N4 sites results in exceptional catalytic ozonation efficiency, surpassing that of intact Fe─N4 sites and commercial MnO2 by 10 and 312 times, respectively. Theoretical calculations and experimental data demonstrated that carbon-defect engineering induces selective cleavage of C─N bond neighboring the Fe─N4 motif. This induces an increase in non-uniform charges and Fermi density, leading to elevated energy levels at the center of Fe d-band. Compared to the intact atomic configuration, carbon-defective Fe─N4 site is more activated to strengthen the interaction with O3 and weaken the O─O bond, thereby reducing the barriers for highly active surface atomic oxygen (*O/*OO), ultimately achieving efficient oxidation of CH3SH and its intermediates. This research not only offers a viable approach to enhance the catalytic ozonation activity of M─N─C but also advances the fundamental comprehension of how periphery carbon environment influences the characteristics and efficacy of M─N4 sites.

Advancements in Electrocatalytic Nitrogen Reduction: A Comprehensive Review of Single-Atom Catalysts for Sustainable Ammonia Synthesis.

Electrocatalytic nitrogen reduction technology seamlessly aligns with the principles of environmentally friendly chemical production. In this paper, a comprehensive review of recent advancements in electrocatalytic NH3 synthesis utilizing single-atom catalysts (SACs) is offered. Into the research and applications of three categories of SACs: noble metals (Ru, Au, Rh, Ag), transition metals (Fe, Mo, Cr, Co, Sn, Y, Nb), and nonmetallic catalysts (B) in the context of electrocatalytic ammonia synthesis is delved. In-depth insights into the material preparation methods, single-atom coordination patterns, and the characteristics of the nitrogen reduction reaction (NRR) are provided. The systematic comparison of the nitrogen reduction capabilities of various SAC types offers a comprehensive research framework for their integration into electrocatalytic NRR. Additionally, the challenges, potential solutions, and future prospects of incorporating SACs into electrocatalytic nitrogen reduction endeavors are discussed.

Accelerated Catalytic Ozonation in a Mesoporous Carbon-Supported Atomic Fe-N4 Sites Nanoreactor: Confinement Effect and Resistance to Poisoning.

The design of a micro-/nanoreactor is of great significance for catalytic ozonation, which can achieve effective mass transfer and expose powerful reaction species. Herein, the mesoporous carbon with atomic Fe-N4 sites embedded in the ordered carbon nanochannels (Fe-N4/CMK-3) was synthesized by the hard-template method. Fe-N4/CMK-3 can be employed as nanoreactors with preferred electronic and geometric catalytic microenvironments for the internal catalytic ozonation of CH3SH. During the CH3SH oxidation process, the mass transfer coefficient of the Fe-N4/CMK-3 confined system with sufficient O3 transfer featured a level of at least 1.87 × 10-5, which is 34.6 times that of the Fe-N4/C-Si unconfined system. Detailed experimental studies and theoretical calculations demonstrated that the anchored atomic Fe-N4 sites and nanoconfinement effects regulated the local electronic structure of the catalyst and promoted the activation of O3 molecules to produce atomic oxygen species (AOS) and reactive oxygen species (ROS), eventually achieving efficient oxidation of CH3SH into CO2/SO42-. Benefiting from the high diffusion rate and the augmentation of AOS/ROS, Fe-N4/CMK-3 exhibited an excellent poisoning tolerance, along with high catalytic durability. This contribution provides the proof-of-concept strategy for accelerating catalytic ozonation of sulfur-containing volatile organic compounds (VOCs) by combining confined catalysis and atomic catalysts and can be extended to the purification of other gaseous pollutants.

Efficient optimization and development of two methods for the determination of acrylamide in deep-frying oil by liquid chromatography-tandem mass spectrometry: Application of multifactor analysis assessment strategy.

A new multifactor analysis assessment strategy was developed for evaluating, optimizing, and comparing analytical techniques for acrylamide in frying oils. Based on five indices (absolute recovery, absolute matrix effect, the intensity of the full ion scan, and the precursor ion scan to m/z 184 and m/z 241), the proposed strategy was performed with radar analysis, relative contribution analysis, and the entropy-weighted technique for order performance by similarity to ideal solution analysis. Two novel methods based on quick, easy, cheap, effective, rugged, and safe extraction methodology and gel permeation chromatography-liquid-liquid extraction followed by liquid chromatography-tandem mass spectrometry have been developed for the analysis of acrylamide in frying oils. Two methods were suitable for rapid and sensitive analysis of acrylamide in oils in different laboratories, with a limit of quantitation at 2 µg/kg, and the average recovery ranging from 92.5% to 107.8%, with relative standard deviations below 10%. When considering automation efficiency and matrix effects, gel permeation chromatography is the most efficient method, whereas the other method has an advantage when analyzing large samples. The developed methods were used in a pilot study to analyze frying oils with acrylamide content below 9.82 µg/kg, showing that the repeated frying process did not produce significant content of acrylamide in oils.

Identification of UGTs and BCRP as potential pharmacokinetic determinants of the natural flavonoid alpinetin.

Alpinetin is a natural flavonoid showing a variety of pharmacological effects such as anti-inflammatory, anti-tumor and hypolipidemic activities. Here, we aim to determine the roles of UDP-glucuronosyltransferases (UGTs) and breast cancer resistance protein (BCRP) in disposition of alpinetin. Glucuronidation potential of alpinetin was evaluated using pooled human liver microsomes (pHLM), pooled human intestine microsomes (pHIM) and expressed UGT enzymes supplemented with the cofactor UDPGA. Activity correlation analyses with a bank of individual HLMs were performed to identify the main contributing UGT isozymes in hepatic glucuronidation of alpinetin. The effect of BCRP on alpinetin disposition was assessed using HeLa cells overexpressing UGT1A1 (HeLa1A1) cells. Alpinetin underwent extensive glucuronidation in pHLM and pHIM, generating one glucuronide metabolite. Of 12 test UGT enzymes, UGT1A3 was the most active one toward alpinetin with an intrinsic clearance (CLint = Vmax/Km) value of 66.5 µl/min/nmol, followed by UGT1A1 (CLint = 48.6 µl/min/nmol), UGT1A9 (CLint = 21.0 µl/min/nmol), UGT2B15 (CLint = 16.7 µl/min/nmol) and UGT1A10 (CLint = 1.60 µl/min/nmol). Glucuronidation of alpinetin was significantly correlated with glucuronidation of estradiol (an activity marker of UGT1A1), chenodeoxycholic acid (an activity marker of UGT1A3), propofol (an activity marker of UGT1A9) and 5-hydroxyrofecoxib (an activity marker of UGT2B15), confirming the important roles of UGT1A1, UGT1A3, UGT1A9 and UGT2B15 in alpinetin glucuronidation. Inhibition of BCRP by its specific inhibitor Ko143 significantly reduced excretion of alpinetin glucuronide, leading to a significant decrease in cellular glucuronidation of alpinetin. Our data suggest UGTs and BCRP as two important determinants of alpinetin pharmacokinetics.

Pharmacokinetic characterization of anhuienoside C and its deglycosylated metabolites in rats.

1. Anhuienoside C (AC), a triterpenoid saponin derived from the traditional Chinese medicine (TCM) "Di Wu", has significant anti-inflammatory and anti-rheumatoid arthritis activities. Here we aimed to characterize the pharmacokinetics of AC and its deglycosylated metabolites in rats. 2. AC was administered to rats by intravenous injection or oral gavage. AC and its four deglycosylated metabolites (M1, M2, M3 and M4) in biological samples were quantified using a UPLC-QTOF/MS system. The pharmacokinetic data were analyzed by compartmental modeling. The metabolism of M1, M2, M3 and M4 was determined using rat liver microsomes (RLM) and rat intestine microsomes (RIM). The intestinal permeabilities of AC and its metabolites were evaluated using Parallel artificial membrane permeability assay (PAMPA) and MDR1-transfected Madin-Darby canine kidney cell (MDCK-MDR1) cell model. 3. AC pharmacokinetics was well described by the one-compartment model. The oral bioavailability of AC was exceedingly low (F = 0.03%). Consistently, AC was poorly distributed (< 0.08 µM) in major organs including the heart, liver, spleen, lung and kidney after oral uptake. Three of four deglycosylated metabolites (M2, M3, and M4) underwent further metabolism in RLM, generating five, two and five oxidized products, respectively. Both PAMPA and MDCK-MDR1 experiments showed that AC and its metabolites were poorly permeable. Furthermore, the net flux ratios derived from MDCK-MDR1 versus wild-type MDCK cells were, respectively 1.3, 1.5, 0.7, 1.2 and 0.6 for AC, M1, M2, M3 and M4, suggesting that these compounds were non-substrates of P-glycoprotein. 4. In conclusion, extensive pre-systemic metabolism and poor permeability were the main causes of low systemic exposures of oral AC and its four metabolites.

New ecdysteroid and ecdysteroid glycosides from the roots of Serratula chinensis.

Three new ecdysteroid glycosides (1-3) and one new ecdysteroid (4), were isolated from the roots of Serratula chinensis. Their structures were established on the basis of extensive spectroscopic analysis and chemical methods.

[Two new triterpenoid glycosides from leaves of Ilex latifolia].

Two new triterpenoid glycosides, latifolosides R and S (1 and 2), were isolated from the leaves of Ilex latifolia by various column chromatographic methods. Their structures were elucidated based on NMR spectroscopic data and chemical evidence.

Metabolite profiling of anhuienoside C by rat intestinal bacteria using the LC-MS metabolomic approach.

1.Anhuienoside C (A-C) is the main active component of the saponin exact of "Di Wu", an oral drug for rheumatism treatment in China. In this study, we aimed to elucidate the metabolic pathways of A-C by intestinal bacteria using the metabolomic approach. 2.Four deglycosylated metabolites (M1, M2, M3 and M4) were identified after A-C (50 µM) was incubated with rat fecal lysate. Chemical structures of these metabolites were determined by high-resolution masses and nuclear magnetic resonance (NMR). 3.A one-compartment pharmacokinetic model was used to describe the formation of bacterial metabolites at a dose of 10 µM A-C. The results revealed that formation of M1 and M2 was rapid, whereas formation of M3 was rather slow. Further, it was found that the metabolites were generated by successive cleavage of the glycosyl residues. 4.This is the first report that A-C is subjected to efficient bacterial metabolism in the gut with M1 and M2 as main metabolites. Our study should be helpful for a better understanding of in vivo disposition of oral A-C.

Triterpenoid saponins from the rhizomes of Anemone flaccida and their inhibitory activities on LPS-induced NO production in macrophage RAW264.7 cells.

A new ursane-type triterpenoid saponin, flaccidoside IV (1), and three new oleanane-type triterpenoid saponins, flaccidosides V-VII (2-4), along with 17 known saponins (5-21), were isolated from the rhizomes of Anemone flaccida. The structures of the new triterpenoid saponins were determined based on spectroscopic analyses and chemical methods. All the isolated saponins were tested for their inhibitory activities on lipopolysaccharide-induced nitric oxide production in RAW264.7 macrophages, and several bisdesmosidic oleanane-type triterpenoid saponins (2, 7, and 10) showed significant inhibitory activities, which indicated they had potential anti-inflammatory activities under their noncytotoxic concentrations in vitro.

[A new flavone C-glycoside from leaves of Lophatherum gracile].

Several kinds of column chromatography method were used to investigate the chemical constituents of the leaves of Lophatherum gracile. The structures of the isolated compounds were identified based on their physicochemical properties and spectral data. A new flavone C-glycoside was isolated and its structure was identified as 3'-methoxyl-luteolin 6-C-beta-D-galactopyranosiduronic acid (1 --> 2) -alpha-L-arabinopyranoside (1).

[A new chromone glycoside from roots of Polygonum multiflorum].

Several kinds of column chromatography methods were used to investigate the chemical constituents of roots of Polygonum multiflorum. The structures of the isolated compounds were identified based on their physicochemical properties, spectral data and chemical methods. A new chromone glycoside was isolated and its structure was identified as (S)-2-(2'-hydroxypropyl)-5-methyl7-hydroxychromone-7-0-alpha-L-fucopyranosyl (1-->2)-beta-D-glucopyranoside (1).

MnO2-based capacitive system enhances ozone inactivation of bacteria by disrupting cell membrane.

The application of ozone (O3) disinfection has been hindered by its low solubility in water and the formation of disinfection by-products (DBPs). In this study, capacitive disinfection is applied as a pre-treatment for O3 oxidation, in which manganese dioxide with a rambutan-like hollow spherical structure is used as the electrode to increase the charge density on the electrode surface. When a voltage is applied, the negative-charged microbes are attracted to the electrodes and killed by electrical interactions. The contact between microbes and capacitive electrodes leads to changes in cell permeability and burst of reactive oxygen species, thereby promoting the diffusion of O3 into the cells. After O3 penetrates the cell membrane, it can directly attack the cytoplasmic constituents, accelerating fatal and irreversible damage to pathogens. As a result, the performance of the capacitance-O3 process is proved better than the direct sum of the two individual process efficiencies. The design of capacitance-O3 system is beneficial to reduce the ozone dosage and DBPs with a broader inactivation spectrum, which is conducive to the application of ozone in primary water disinfection.

Quality assessment of commercial dried ginger (Zingiber officinale Roscoe) based on targeted and non-targeted chemical profiles and anti-inflammatory activity.

Dried ginger, a well-known medicine and food homologous production, has been widely circulated in China with high health benefits and economic value. Currently, there is still a lack of quality assessment on whether dried ginger in China exhibits chemically and biologically distinct properties, which creates a barrier to its quality control in commercial circulation. In this study, the chemical characteristics of 34 batches of common dried ginger samples in China were first explored using non-targeted chemometrics based on the UPLC-Q/TOF-MS analysis, leading to the identification of 35 chemicals that contributed to clustering into two categories, with sulfonated conjugates being the key chemically distinct components. By comparing the samples before and after sulfur-containing treatment and the further synthesis of a key differentiating component of [6]-gingesulfonic acid, it was then demonstrated that sulfur-containing treatment was the primary cause of the formation of sulfonated conjugates, as opposed to regional or environmental factors. Furthermore, the anti-inflammatory efficacy of dried ginger with high presence of sulfonated conjugates was significantly decreased. Consequently, for the first time, UPLC-QqQ-MS/MS was used to develop a targeted quantification method for 10 characteristic chemicals in dried ginger, allowing researchers to quickly determine whether dried ginger has been processed with sulfur and quantitatively evaluate the quality of dried ginger. These results provided an insight into the quality of commercial dried ginger in China and a suggested method for its quality supervision as well.

Artificial Intelligence Uncovers Natural MMP Inhibitor Crocin as a Potential Treatment of Thoracic Aortic Aneurysm and Dissection.

Thoracic aortic aneurysm and dissection (TAAD) is a lethal cardiovascular condition without effective pharmaceutical therapy. Identifying novel drugs that target the key pathogenetic components is an urgent need. Bioinformatics analysis of pathological studies indicated "extracellular matrix organization" as the most significant functional pathway related to TAAD, in which matrix metallopeptidase (MMP) 2 and MMP9 ranked above other proteases. MMP1-14 were designated as the prototype molecules for docking against PubChem Compound Database using Surflex-Dock, and nine natural compounds were identified. Using a generic MMP activity assay and an aminopropionitrile (BAPN)-induced TAAD mouse model, we identified crocin as an effective MMP inhibitor, suppressing the occurrence and rupture of TAAD. Biolayer interferometry and AI/bioinformatics analyses indicated that crocin may inhibit MMP2 activity by direct binding. Possible binding sites were investigated. Overall, the integration of artificial intelligence and functional experiments identified crocin as an MMP inhibitor with strong therapeutic potential.

Benzamides and quinazolines from a mangrove actinomycetes Streptomyces sp. (No. 061316) and their inhibiting caspase-3 catalytic activity in vitro.

One new benzamide, 3-hydroxyl-2-N-iso-butyryl-anthranilamide (1), together with two known benzamides (2, 3) and three known quinazolines (4-6), was isolated from a mangrove actinomycetes Streptomyces sp. (No. 061316), which displayed inhibiting Caspase-3 activity in vitro. The structure of 1 was elucidated by electrospray ionization (ESI)-MS, NMR spectroscopies and X-ray crystal diffraction. After evaluation of all compounds for their inhibitory effect on Caspase-3 in vitro, 3-hydroxyl-anthranilamide (2) and 8-hydroxyl-2,4-dioxoquinazoline (6) showed activity against Caspase-3 with IC(50) values of 32 and 36 µM, respectively.

Two new psathyrelloid species of Coprinopsis (Agaricales, Psathyrellaceae) from China.

In this study, Coprinopsisjilinensis and Coprinopsispusilla were introduced, based on their morphological characteristics, the internal transcribed spacer (ITS) and large subunit ribosomal (LSU) region sequences of nrDNA. These new psathyrelloid species were found in Jilin Province, China. Coprinopsisjilinensis has brown pileus, utriform pleurocystidia, brown, smooth, dextrinoid basidiospores and tiny pore. It mainly grows on humus. Coprinopsispusilla has small basidiomata, greyish-white pileus, thick and distinct veil at edges, subcolourless and verrucose basidiospores. It is poreless and it grows on the decaying wood of broad-leaved trees. Both of them belong to the C.sect.Melanthinae. A supplementary description of C.sect.Melanthinae was given in combination with the newly-discovered taxa and an identification key to the fourteen psathyrelloid species of Coprinopsis is provided. Coprinopsissect.Canocipes and C.sect.Quartoconatae were evaluated and the phylogenetic position of the psathyrelloid species of Coprinopsis was discussed. Psathyrellasubagraria, as a confusing species, was also discussed in this study.

A novel Fe3+-stabilized magnetic polydopamine composite for enhanced selective adsorption and separation of Methylene blue from complex wastewater.

Herein, a novel Fe3+-stabilized magnetic polydopamine composite (Fe3O4/PDA-Fe3+) was facilely constructed, systematically characterized, and subsequently applied for the first time as a versatile adsorbent for treatment of Methylene blue (MB) in complex wastewater. Results showed that as-prepared material had prominent adsorption ability toward MB in its single dye solution over a wide pH range (3-10) with qmax value of 608.8 mg/g at 318 K. More interestingly, MB could be selectively captured by resulting adsorbent from mixed dye solutions (MB-cationic dye and MB-anionic dye) and complex aqueous solution with high ionic strength up to 0.5 mol/L NaCl. It was eventually revealed that the enhanced and selective adsorption of MB by as-resultant adsorbent was due to the synergistic effects between multiple uptake mechanisms. What's more, its adsorption efficiency toward MB in simulated wastewater still maintained higher than 80 % of its original uptake performance after several runs of adsorption-desorption. Additionally, it exhibited more superior uptake performance toward MB than commercial powder activated carbon (PAC) in column adsorption system. Thus, the outstanding sorption ability, unique capture selectivity, as well as excellent stability and recyclability for model wastewater endow it a promising candidate adsorbent for selective adsorption and separation of MB from complex wastewater.