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Atenolol (ATL) is a cardioselective β1-receptor antagonist used to treat cardiovascular disorders such as hypertension and angina. It belongs to the biopharmaceutical classification system (BCS) class III, for which permeation across the intestinal membrane is the rate-limiting step. This study aims to screen biologically acceptable salts of ATL to improve its diffusion properties using six dicarboxylic acids such as oxalic acid (OXA), fumaric acid (FUM), malic acid (MAL), glutaric acid (GLU), adipic acid (ADP) and pimelic acid (PIM). The organic salts were subjected to solid-state characterization such as powder XRD, single crystal XRD, DSC/TGA, and FT-IR spectroscopy. The crystal structures confirm the proton transfer from the carboxylic acid to the isopropyl amine fraction of ATL. Among the multicomponent salts, ATL forms anhydrous salts with GLU/MAL, whereas ATL–OXA/FUM/ADP/PIM are confirmed to be salt hydrates. Similar to the native drug, all the salts maintained stability for more than 1 month during exposure to 35 ± 5 °C/75 ± 5% relative humidity conditions. In addition, the salts were thermally stable at 50 °C for an hour. The aqueous solubility and diffusion study of the ATL salts (ATL–ADP/FUM/PIM/GLU/MAL/OXA) in pH 6.8 phosphate buffer indicated improved solubility (up to 33-fold) and flux (up to 2.8-fold) compared to the native drug due to ionic interactions between the drug and the counterion. Improved diffusion properties of the ATL salts are partially correlated with their enhanced solubility distribution coefficients and log P of the salt former. [ABSTRACT FROM AUTHOR]

Isotactic polypropylene (iPP) is the most prominent form of polypropylene, and β-phase is the most resistant to impact compared to the crystalline forms. However, β-phase is the least frequently obtained under conventional operating conditions. TiO2 nanoparticles were functionalized with dicarboxylic acids as nucleating agents to promote β-crystal formation in iPP. The effects of three dicarboxylic acids – glutaric, pimelic, and azelaic – were characterized on TiO2-modified surfaces. Additionally, the interactions between TiO2 and water molecules, crucial for the formation of chelating or bridging linkages, were analyzed using Fourier Transform Infrared spectroscopy. For pimelic and azelaic acids at the polymer processing temperature, the carboxyl group band disappeared, suggesting a transition of the acid-calcium union from a bridging to a chelating linkage due to the presence of water molecules. These molecules help maintain the stability of the chains during processing. X-ray diffraction (XRD) analysis confirmed a higher content of β-crystalline structures in iPP when modified with pimelic and azelaic acids. The research indicates that water molecules, desorbed during manufacturing, facilitate the chelating form, thereby enhancing β-nucleation and improving the surface properties of iPP composites. These β-nucleated PP composites represent a promising material solution for medical device applications, offering a compelling combination of enhanced properties and cost-effectiveness. [ABSTRACT FROM AUTHOR]

Design of material showing contraction upon heating is highly challenging due to varying mechanism. However, imidazole is found to be a potential molecule that may provide low CTE materials when incorporated in the matrix. Here we have reported thermal expansion property of imidazolium salts of five aliphatic α, ω‐alkane dicarboxylic acids and three aromatic acids. Either uniaxial or biaxial negative thermal expansion (NTE) has been observed in most of the salts. In some cases, axial zero thermal expansion (ZTE) has been observed. The role of imidazolium moiety for the anomalous thermal expansion behaviour of the salts has been analyzed in this study. The controlled TE behaviour of the salts is attributed to the hydrogen bonding and transverse vibration in all imidazolium salts. Owing to the high transverse vibration observed in imidazolium ion as well as the heavier oxygen atoms of acids in each case, the distance between hydrogen bonded atoms decreases–which provides either low expansion or contraction along one of the principal axes. [ABSTRACT FROM AUTHOR]

Fumarate is an unsaturated dicarboxylic acid useful as a raw material for unsaturated polyester resins, polybutylene succinate (PBS), poly(propylene fumarate) (PPF), plasticisers, and other products. Biodegradable plastics derived from fumarate are an attractive solution to the serious environmental pollution caused by plastic disposal. A new fumarate production from CO2 and biobased pyruvate using enzymes in aqueous media under ambient temperature and pressure is an environmental approach to overcome plastic pollution and achieve CO2 capture, utilization and storage (CCUS). In this work, fumarate production from pyruvate and low-concentration CO2 below 15% captured from the gas phase using 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES)-NaOH buffer solution with a multi-enzyme system consisting of pyruvate carboxylase from a bovine liver (PC; EC 6.4.1.1), recombinant malate dehydrogenase from bacteria (MDH; EC 1.1.1.37) and fumarase from a porcine heart (FUM; EC 1.1.1.37) in the presence of adenosine 5′-triphosphate (ATP) and NADH was investigated. It was found that pyruvate can be converted into L -malate in high yields (more than 80%) directly using 15% CO2 equivalent to exhaust gas as a carboxylating agent using a dual-enzyme system consisting of PC and MDH in the presence of ATP and NADH after 5 h incubation. Moreover, fumarate production from 15% CO2 and pyruvate as raw materials was accomplished using a dual-enzyme system consisting of PC and MDH. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to explore the potential mechanism of Helicobacter pylori (Hp) eradication by probiotic therapy through 16S rRNA gene sequencing technology and untargeted metabolomics. Methods: Twenty four Hp-infected children were recruited from the Shanxi Bethune Hospital, and 24 healthy children were recruited as a blank control group. Group A: fecal samples from 24 healthy children. Group B: fecal samples of 24 children with Hp infection. Group B1 (n = 15): fecal samples of group B treated with probiotic therapy for 2 weeks. Group B2 (n = 19): fecal samples of group B treated with probiotic therapy for 4 weeks. The above fecal samples were analyzed by 16S rRNA gene sequencing technology and untargeted metabolomics. Results: There was no significant difference in alpha diversity and beta diversity among the four groups, but many bacteria with statistical difference were found in each group at the bacterial genus level and phylum level. LEfSe results showed that in group B, Porphyromonadaceae , Shigella and other microorganisms related to intestinal microecological dysbiosis were enriched. And in group B2, abundant characteristic microorganisms were found, namely Bacillales and Prevotella. KEGG metabolic pathway enrichment analysis showed that groups B1 and B2 were involved in 10 metabolic pathways potentially related to probiotic treatment: purine metabolism, nitrogen metabolism, arginine biosynthesis, alanine, aspartic acid and glutamate metabolism, glyoxylic acid and dicarboxylic acid metabolism, unsaturated fatty acid biosynthesis, fatty acid extension, fatty acid degradation, pyrimidine metabolism, fatty acid biosynthesis. Conclusion: Probiotic therapy can inhibit Hp to some extent and can relieve gastrointestinal symptoms, making it a preferred therapy for children with Hp infection and functional abdominal pain. Hp infection can reduce the diversity of intestinal microbes, resulting in the disturbance of intestinal microbiota and changes in the relative abundance of microbiota in children, while probiotic therapy can restore the diversity of intestinal microbes and intestinal microecological balance. [ABSTRACT FROM AUTHOR]

A post-synthetic modification was employed to incorporate lanthanide Eu3+ ions into carbazole-functionalized UiO-67 metal–organic frameworks, successfully fabricating an efficient dual-emission fluorescence probe. The Eu3+-doped composite manifests superior luminescent properties and remarkable fluorescence stability, attributable to the sensitization and reinforcement afforded by the parent framework. Notably, the ligand's capability to capture external light and sensitize Eu3+ emissions led to observing characteristic peaks at 435 nm for the intrinsic ligand and 591, 614, 651, and 701 nm for Eu3+. The introduction of dipicolinic acid (DPA) serves a dual role: it acts as an antenna to absorb photons and replaces the coordinated water molecules of Eu3+, thereby preventing fluorescence quenching by water's O–H vibrations. Additionally, establishing hydrogen bonding between DPA and the carbazole dicarboxylic acid (CDC) initiates an intermolecular charge transfer (ICT) process, enhancing the ligand's fluorescence. Besides, the addition of DPA concurrently enhances the fluorescence emissions of both the ligand and Eu3+, displaying an unusual dual-enhanced "turn-on" fluorescence mode with an impressively low detection limit of 0.538 μM, accompanied by discernible color changes visible to the naked eye. Utilizing Eu@UiO-67-CDC as a test paper facilitates rapid on-site detection of DPA, eliminating the need for complex instrumentation. Moreover, the Eu@UiO-67-CDC probe can quantify DPA in environmental matrices such as river and lake water, with better recovery rates, indicating its significant potential for practical applications. [ABSTRACT FROM AUTHOR]

Amino acids are present in all known life, so identifying the environmental conditions under which they can be synthesized constrains where life on Earth might have formed and where life might be found on other planetary bodies. All known abiotic amino acid syntheses require ammonia, which is only produced in reducing and neutral atmospheres. Here, we demonstrate that the Fe-bearing hydroxide mineral ferroan brucite [Fe0.33,Mg0.67(OH)2] can mediate the reaction of nitrate and glyoxylate to form glycine, the simplest amino acid used in life. Up to 97% of this glycine was detected only after acid digestion of the mineral, demonstrating that it had been strongly partitioned to the mineral. The dicarboxylic amino acid 3-hydroxy aspartate was also detected, which suggests that reactants underwent a mechanism that simultaneously produced mono-and dicarboxylic amino acids. Nitrate can be produced in both neutral and oxidizing atmospheres, so reductive amination of nitrate and glyoxylate on a ferroan brucite surface expands origins of life scenarios. First, it expands the environmental conditions in which life's precursors could form to include oxidizing atmospheres. Second, it demonstrates the ability of ferroan brucite, an abundant, secondary mineral in serpentinizing systems where olivine is partly hydrated, to mediate reductive amination. Finally, the results demonstrate the need to consider mineral-bound products when analyzing samples for abiotic amino acid synthesis. [ABSTRACT FROM AUTHOR]

Adjusting the morphology and structure of the catalyst to optimize the structure of the discharge product is an effective strategy for improving the electrocatalytic activity of lithium–oxygen batteries (LOBs). In this paper, a novel high‐orientation layered manganese‐based metal–organic frameworks (Mn‐MOFs) catalyst for the air cathode of a LOB is synthesized via a facile solvothermal method using 2,4‐pyridine dicarboxylic acid combined with the metal Mn2+ ion. The presence of layered structure increases the specific surface area of the catalytic material, and the interlayer spacing can be used as a channel for electron and oxygen transport, thus promoting ion diffusion and catalyzing reactions. Otherwise, the coordination of the N element and metal ion in the organic ligand significantly improves the electrical conductivity and oxygen reduction reaction/oxygen extraction reaction (ORR/OER) performance of LOB. The effective combination of Mn2+ and 2,4‐pyridine dicarboxylic acid improves the overall catalytic capacity of the material, leading to a high LiO2 adsorption capacity so as to induce the formation of film discharge products and extend the cycle life of LOBs. When using Mn‐MOFs at 140°C as the cathode catalyst, the specific discharge capacity of the LOB can achieve 5579 mAh/g with a 0.2 mA/cm2 current density and maintain 140 stable cycles, limiting the specific discharge capacity to 500 mAh/g. [ABSTRACT FROM AUTHOR]

CO2 chemical fixation offers a feasible approach for carbon mitigation and high‐value utilization, but it is still challenging to develop an efficient catalyst for CO2 conversion into cyclic carbonate. Herein, the triethylenediamine‐derived dicationic ionic liquids (DIL‐X, X = Cl, Br, and I) were grafted into UiO‐66 linkers through self‐assembly of Zr4+ ions and the mixed ligands of terephthalic acid and DIL‐bearing dicarboxylic acid, resulting in UiO‐66‐DIL‐Xn, (n designated as molar amount of the feeding DIL‐X). Their catalytic performance was evaluated by the epoxide cycloaddition reaction in the absence of solvent and cocatalyst. Among them, the UiO‐66‐DIL‐Cl0.4 catalyst exhibited outstanding performance, with a chloropropene carbonate yield of 92% and a high selectivity of 99% under 0.1 MPa CO2 at 110 °C for 16 h. Its high activity could be ascribed to the cooperativity among Lewis acidity of MOF nodes, the enhanced CO2 absorption, and the strong nucleophilicity offered by halogen ions of ionic liquid‐modified MOF. Moreover, UiO‐66‐DIL‐Cl0.4 presented excellent recyclability and substrate extension. A potential catalytic mechanism for the epoxide‐CO2 cycloaddition into cyclic carbonate has been proposed. This work will shed light on the rational design of functionalized MOFs‐based catalysts for CO₂ utilization. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 4-month-old infant who presented to the emergency department with diarrhea, irritability, and poor reactions. Topics discussed include the infant's clinical symptoms and examination findings, abnormal laboratory results indicating metabolic disturbances, and the implications of the patient's premature birth on her overall health status.

Summary: Malate and fumarate constitute a significant fraction of the carbon fixed by photosynthesis, and they are at the crossroad of central metabolic pathways. In Arabidopsis thaliana, they are transiently stored in the vacuole to keep cytosolic homeostasis.The malate and fumarate transport systems of the vacuolar membrane are key players in the control of cell metabolism. Notably, the molecular identity of these transport systems remains mostly unresolved. We used a combination of imaging, electrophysiology and molecular physiology to identify an important molecular actor of dicarboxylic acid transport across the tonoplast.Here, we report the function of the A. thaliana Aluminium‐Activated Malate Transporter 5 (AtALMT5). We characterised its ionic transport properties, expression pattern, localisation and function in vivo. We show that AtALMT5 is expressed in photosynthetically active tissues and localised in the tonoplast. Patch‐clamp and in planta analyses demonstrated that AtALMT5 is an ion channel‐mediating fumarate loading of the vacuole. We found in almt5 plants a reduced accumulation of fumarate in the leaves, in parallel with increased malate concentrations.These results identified AtALMT5 as an ion channel‐mediating fumarate transport in the vacuoles of mesophyll cells and regulating the malate/fumarate balance in Arabidopsis. [ABSTRACT FROM AUTHOR]

Photosynthetic eukaryotes have metabolic pathways that occur in distinct subcellular compartments. However, because metabolites synthesized in one compartment, including fixed carbon compounds and reductant generated by photosynthetic electron flows, may be integral to processes in other compartments, the cells must efficiently move metabolites among the different compartments. This review examines the various photosynthetic electron flows used to generate ATP and fixed carbon and the trafficking of metabolites in the green alga Chlamydomomas reinhardtii; information on other algae and plants is provided to add depth and nuance to the discussion. We emphasized the trafficking of metabolites across the envelope membranes of the two energy powerhouse organelles of the cell, the chloroplast and mitochondrion, the nature and roles of the major mobile metabolites that move among these compartments, and the specific or presumed transporters involved in that trafficking. These transporters include sugar-phosphate (sugar-P)/inorganic phosphate (Pi) transporters and dicarboxylate transporters, although, in many cases, we know little about the substrate specificities of these transporters, how their activities are regulated/coordinated, compensatory responses among transporters when specific transporters are compromised, associations between transporters and other cellular proteins, and the possibilities for forming specific 'megacomplexes' involving interactions between enzymes of central metabolism with specific transport proteins. Finally, we discuss metabolite trafficking associated with specific biological processes that occur under various environmental conditions to help to maintain the cell's fitness. These processes include C4 metabolism in plants and the carbon concentrating mechanism, photorespiration, and fermentation metabolism in algae. [ABSTRACT FROM AUTHOR]

Oxalate, the simplest dicarboxylic acid, is a prevalent antinutrient that chelates with various metals and can lead to the formation of kidney stones in humans. The accurate detection of the oxalate concentration in food and the cultivation of low-oxalate crops are important for enhancing public health. In this study, we established a high-throughput and highly sensitive technique for oxalate detection using ultra-high-performance liquid chromatographic–triple quadrupole tandem mass spectrometry (UPLC-QqQ-MS/MS). Additionally, we overexpressed the gene O7, which encodes oxalyl-CoA synthetase in the maize oxalate degradation pathway, resulting in O7-OE lines. By employing the UPLC-QqQ-MS/MS method to measure oxalate levels in these transgenic lines, we observed that the oxalate content in the kernels of O7-OE lines was reduced by approximately 43%, with a concurrent increase in some micronutrients such as zinc. Importantly, the transgenic maize showed normal seed storage compound accumulation or other agronomic characteristics. In summary, we developed a high-throughput detection method that advances oxalate measurement. Furthermore, by generating new maize germplasm with diminished oxalate, our work offers potential health advantages to consumers. [ABSTRACT FROM AUTHOR]

This article analyzes the effect of the type of surface modification (using silane coupling agents and dicarboxylic acids) on titanium dioxide particles used as fillers in polylactic acid composites, which were exposed to a photodegradative process. The thermomechanical properties of the composites were analyzed; it was found that the silane coupling agent with Imidazole allowed the composites to have Young’s modulus values 60% lower than the composite without filler. On the other hand, the crystallization rate was 30% higher for composites with azelaic Acid attached to TiO2 particles than for composites without filler at a cooling rate of 5°C min−1. Once degraded composites containing azelaic acid were the least brittle, with a minor increment in Young’s Modulus compared to pure polylactic acid composites. When a mixture of modified titanium dioxide particles (with imidazole and either azelaic acid or pimelic acid) was used, there was a synergistic effect regarding photostability. [ABSTRACT FROM AUTHOR]

In this paper, a series of Zr metal‐organic frameworks, whose hexanuclear clusters of Zr are connected with luminescent rodlike dicarboxylic acids, are used for the construction of a sensor array to selectively detect various analyte vapors. The chemical functionalization of the ligand (HOOC[PE‐aryl‐EP]COOH) (which alternates phenylene(P) and ethynylene(E) units) through the aryl core, is focused on obtaining six Porous Interpenetrated Zirconium‐Organic Frameworks (PIZOFs) with distinctive luminescent properties. Particularly, the synthesis of two new ligands (aryl = nitrobenzene;metal‐organic frameworks aryl = pyrazine) enabled the preparation of new PIZOFs (UPO‐1 and UPO‐2) with submicron sizes, thanks to the use of a microwave‐assisted synthetic method. The fluorescence properties of these two new PIZOFs, along with four others already reported, are thoroughly evaluated and noticeable changes are observed in their optical properties based on variations in the aryl core of the ligands. Furthermore, the presence of various volatile analyte vapors particularly modified their characteristic emission, resulting in multiple optical responses that are combined to achieve selectivity in detecting these analytes. Specifically, the construction of a fluorescent sensor array is proposed, incorporating the six PIZOFs into polyvinylidene‐fluoride (PVDF) films, capable of producing unique identification patterns for each analyte by leveraging the cross‐responsiveness of these sensing materials. [ABSTRACT FROM AUTHOR]

The singlet fission characteristics of aqueous nanoparticles, self‐assembled from ion pairs of tetracene dicarboxylic acid and various amines with or without chirality, are thoroughly investigated. The structure of the ammonium molecule, the counterion, is found to play a decisive role in determining the molecular orientation of the ion pairs and its regularity, spectroscopic properties, the strength of the intermolecular coupling between the tetracene chromophores, and the consequent singlet fission process. Using chiral amines has led to the formation of crystalline nanosheets and efficient singlet fission with a triplet quantum yield as high as 133% ±20% and a rate constant of 6.99 × 109 s−1. The chiral ion pairs also provide a separation channel to free triplets with yields as high as 33% ±10%. In contrast, nanoparticles with achiral counterions do not show singlet fission, which gave low or high fluorescence quantum yields depending on the size of the counterions. The racemic ion pair produces a correlated triplet pair intermediate by singlet fission, but no decorrelation into two free triplets is observed, as triplet‐triplet annihilation dominates. The introduction of chirality enables higher control over orientation and singlet fission in self‐assembled chromophores. It provides new design guidelines for singlet fission materials. [ABSTRACT FROM AUTHOR]

Upcycling is emerging as a crucial strategy for enhancing the value of polymers, driving the transition toward a circular material economy. In this study, we present a facile chemical method for converting high-density polyethylene (HDPE) waste into valuable long-chain dicarboxylic acids (LCDCAs) via a key enabling unsaturated double-bond formation step. That is, we propose introducing unsaturation points in HDPE using commercially available heterogeneous catalysts (e.g. Pt/Al2O3). The unsaturation level through C＝C double bond formation is around 10%, as confirmed by FTIR, Raman and X-ray photoelectron spectroscopy. A process of microwave-assisted oxidation is demonstrated to break down the dehydrogenated HDPE into a mixture of aliphatic diacids. This approach enhances the recyclability and value of HDPE by the transformation of polymer waste into bifunctional monomers for potentially novel polyester synthesis. This process offers a sustainable and value-added alternative to conventional recycling methods. While further optimizations are needed, initial estimates of the E-factor and sEF provide promising indicators of the potential environmental benefits of this upcycling approach. [ABSTRACT FROM AUTHOR]

Polyvinyl alcohol (PVA) was crosslinked with a homologous series of four different dicarboxylic acids, HOOC(CH2) n‐2COOH (n = 2 to 5) viz. oxalic acid (OA; C2), malonic acid (MA; C3), succinic acid (SA; C4) and glutaric acid (GA; C5) containing odd and even number of carbon atoms. The characterization and assessment of synthesized crosslinked films were done using ATR‐FTIR, XRD, SEM, AFM, DSC, rheology, percent swelling and sessile drop contact angle. The odd‐even effect of dicarboxylic acids was observed to significantly influence the physicochemical properties of PVA when employed as a crosslinker. PVA films crosslinked using dicarboxylic acids containing an even number of carbon atoms, displayed translucency, roughness, and an irregular matrix. In contrast, films incorporating an odd number of carbon atoms were transparent, homogenous, and densely packed. Furthermore, films containing even acids exhibited relatively lower crystallinity, lower melting temperature (Tm) and displayed an unexpected irregular trend in swelling as crosslinker concentration increased compared to films containing dicarboxylic acids with an odd number of carbon atoms which exhibits a consistent swelling with increasing crosslinker concentration. These results are attributed to the difference in the solubility and crystal structures of the odd‐even series of dicarboxylic acids. [ABSTRACT FROM AUTHOR]

ABSTRACT Malate is an important dicarboxylic acid produced from fumarate in the tricarboxylic acid cycle. Deficiencies of fumarate hydrolase (FH) and malate dehydrogenase (MDH), responsible for malate formation and metabolism, respectively, are known to cause recessive forms of neurodevelopmental disorders (NDDs). The malic enzyme isoforms, malic enzyme 1 (ME1) and 2 (ME2), are required for the conversion of malate to pyruvate. To date, there have been no reports linking deficiency of either malic enzyme isoforms to any Mendelian disease in humans. We report a patient presenting with NDD, subtle dysmorphic features, resolved dilated cardiomyopathy, and mild blood lactate elevation. Whole exome sequencing (WES) revealed a homozygous frameshift variant (c.1379_1380delTT, p.Phe460fs*22) in the malic enzyme 2 (ME2) gene resulting in truncated and unstable ME2 protein in vitro. Subsequent deletion of the yeast ortholog of human ME2 (hME2) resulted in growth arrest, which was rescued by overexpression of hME2, strongly supporting an important role of ME2 in mitochondrial function. Our results also support the pathogenicity and candidacy of the ME2 gene and variant in association with NDD. To our knowledge, this is the first report of a Mendelian human disease resulting from a biallelic variant in the ME encoding gene. Future studies are warranted to confirm ME2‐associated recessive NDD. [ABSTRACT FROM AUTHOR]

Atmospheric secondary aerosols are often internally mixed with organic and inorganic components, particularly dicarboxylic acids, ammonium, sulfate, nitrate, and chloride. These complex compositions enable aqueous reaction between organic and inorganic species, significantly complicating aerosol phase behavior during aging and making phase predictions challenging. We investigated carboxylate–ammonium salt mixtures using attenuated total reflection Fourier-transformed infrared spectroscopy (ATR-FTIR). The mono-, di-, and tricarboxylates included sodium pyruvate (SP), sodium tartrate (ST), and sodium citrate (SC), while the ammonium salts included NH4NO3 , NH4Cl , and (NH4)2SO4. Our results demonstrated that aqueous replacement reactions between carboxylates and ammonium salts were promoted by the formation and depletion of NH3 as relative humidity (RH) changed. For SP/ammonium aerosols, NaNO3 and Na2SO4 crystallized from 35.7 % to 12.7 % and from 65.7 % to 60.1 % RH, respectively, which is lower than the values for pure inorganics (62.5 ± 9 %–32 % RH for NaNO3 and 82 ± 7 %–68 ± 5 % RH for Na2SO4). Upon hydration, the crystalline Na2SO4 and NaNO3 deliquesced at 88.8 %–95.2 % and 76.5 ± 2 %–81.9 %, which is higher than the values of pure Na2SO4 (74 ± 4 %–98 % RH) and NaNO3 (65 %–77.1 ± 3 % RH). In contrast, reaction between ST or SC and (NH4)2SO4 was incomplete due to the gel structure at low RH. Unexpectedly, aqueous Na2SO4 crystallized upon humidification in ST/ (NH4)2SO4 particles at 43.6 % RH and then deliquesced with increasing RH. This is attributed to increased ion mobility in viscous particles, leading to nucleation and growth of Na2SO4 crystals. Our findings highlight the intricate interplay between chemical components within organic/inorganic aerosol and the impact of replacement reactions on aerosol aging, phase state, and subsequently atmospheric processes. [ABSTRACT FROM AUTHOR]

The reactions of the angular ligand 4,4′-oxybis(N-(pyridin-3-yl)benzamide) (L1) and 1,4-naphthalenedicarboxylic acid (1,4-H2NDC) with divalent metal salts yielded three distinct coordination polymers (CPs): {[Zn2(L1)(1,4-NDC)2]·MeOH}n, 1, {[Cu(L1)(1,4-NDC)(H2O)]·3H2O}n, 2, and {[Cd(L1)(1,4-NDC)]·2H2O}n, 3. Complex 1 features a 2-fold interpenetrated 3D framework with the (412·63)-pcu topology, while complex 2 reveals a 1D triple-strained helical chain and complex 3 displays a 3-fold interpenetrated 3D framework with (66)-dia topology. Additionally, the reactions of the flexible ligand N,N′-bis(3-methylpyridyl) adipoamide (L2) afforded {[Co4(L2)0.5(1,4-NDC)3(H2O)3(µ3-OH)2]·EtOH·2H2O}n, 4, {[Zn2(L2)(1,4-NDC)2]·2CH3OH}n, 5, and [Cd(L2)(adipic)(H2O)]n (H2adipic = adipic acid), 6, exhibiting a self-catenated 3D framework with the (420·68)-8T32 topology, a 2D layer with the (413·62) − (4,4)IIb topology, and a 2D layer with the (44·62)-sql topology, respectively. The structural diversity observed in complexes 1–6 highlights the pivotal influence of the metal center on the degree of entanglement in CPs within mixed-ligand systems. The thermal stability and luminescent properties of complexes 1–3, 4, and 6 are also discussed. [ABSTRACT FROM AUTHOR]

Three nickel, copper, and zinc complexes with dicarboxylic acids (3,3′-dithiodipropionic acid (H2dtdp) and fumaric acid (H2fu)) and N-donor ligands (1,10-phenanthroline (phen), N′–methyldipropylenetriamine (mdpta), and N,N,N′,N″,N″-pentamethyldiethylenetriamine (pmdien)) were synthesized. These complexes were characterized using elemental analysis, IR spectroscopy, and single-crystal X-ray diffraction. Interestingly, [Ni(dtdp)(phen)(H2O)3]∙0.5H2O (1) is a mononuclear complex, where the dtdp dianion employs only one carboxylate group for coordination to the central nickel atom. [(ClO4)(mdpta)Cu(μ-dtdp)Cu(mdpta)(H2O)](ClO4) (2) is a dinuclear copper complex with a dtdp bridge and different coordination on the copper center. [{Zn(pmdien)(H2O)}2(μ-fu)](ClO4)2 (3) is a symmetric dimer with a bridging fumarate ligand. These coordination compounds were tested for their antibacterial activities on Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Enterococcus faecalis bacteria strains. All the complexes show moderate activities on the mentioned strains. [ABSTRACT FROM AUTHOR]

Sixty-four phenols grouped as nitrated, bromo, amino, methyl, chloro-phenols, and cresols, and thirty-eight organic acids grouped as mono-carboxylic and dicarboxylic are analyzed in forty-two fog samples collected in the Alsace region between 2015 and 2021 to check their atmospheric behavior. Fogwater samples are collected using the Caltech Active Strand Cloudwater Collector (CASCC2), extracted using liquid–liquid extraction (LLE) on a solid cartridge (XTR Chromabond), and then analyzed using gas chromatography coupled with mass spectrometry (GC-MS). The results show the high capability of phenols and acids to be scavenged by fogwater due to their high solubility. Nitro-phenols and mono-carboxylic acids have the highest contributions to the total phenolic and acidic concentrations, respectively. 2,5-dinitrophenol, 3-methyl-4-nitrophenol, 4-nitrophenol, and 3,4-dinitrophenol have the highest concentration, originating mainly from vehicular emissions and some photochemical reactions. The top three mono-carboxylic acids are hexadecenoic acid (C16), eicosanoic acid (C18), and dodecanoic acid (C12), whereas succinic acid, suberic acid, sebacic acid, and oxalic acid are the most concentrated dicarboxylic acids, originated either from atmospheric oxidation (mainly secondary organic aerosols (SOAs)) or vehicular transport. Pearson's correlations show positive correlations between organic acids and previously analyzed metals (p < 0.05), between mono- and dicarboxylic acids (p < 0.001), and between the analyzed acidic compounds (p < 0.001), whereas no correlations are observed with previously analyzed inorganic ions. Total phenolic and acidic fractions are found to be much higher than those observed for pesticides, polycyclic aromatic hydrocarbons (PAHs), and polychlorinated biphenyls (PCBs) measured at the same region due to their higher scavenging by fogwater. [ABSTRACT FROM AUTHOR]

Garcinia gummi-gutta, commonly known as Garcinia cambogia (syn.), is a popular traditional herbal medicine known for its role in treating obesity, and has been incorporated into several nutraceuticals globally for this purpose. The fruit rind is also used as a food preservative and a condiment because of its high content of hydroxycitric acid, which imparts a sharp, sour flavour. This review highlights the major bioactive compounds present in the tree Garcinia gummi-gutta, with particular emphasis on (2S, 3S)-tetrahydro-3-hydroxy-5-oxo-2,3-furan dicarboxylic acid, commonly referred to as garcinia acid. This acid can be isolated in large amounts through a simple procedure. Additionally, it explores the synthetic transformations of garcinia acid into biologically potent and functionally useful enantiopure compounds, a relatively under-documented area in the literature. This acid, with its six-carbon skeleton, a γ-butyrolactone moiety, and two chiral centres bearing chemically amenable functional groups, offers a versatile framework as a chiron for the construction of diverse molecules of both natural and synthetic origin. The synthesis of chiral 3-substituted and 3,4-disubstituted pyrrolidine-2,5-diones, analogues of the Quararibea metabolite—a chiral enolic-γ-lactone; the concave bislactone skeletons of fungal metabolites (+)-avenaciolide and (−)-canadensolide; the structural skeletons of the furo[2,3-b]furanol part of the anti-HIV drug Darunavir; (−)-tetrahydropyrrolo[2,1-a]isoquinolinones, an analogue of (−)-crispine A; (−)-hexahydroindolizino[8,7-b]indolones, an analogue of the naturally occurring (−)-harmicine; and furo[2,3-b]pyrroles are presented here. [ABSTRACT FROM AUTHOR]

AbstractObjective: Fumaric acid is a dicarboxylic acid that belongs to the phenolic class enriched in fruits and vegetables that are traditionally used for the treatment of various ailments. The research was planned to find out the anti-inflammatory and anti-arthritic activities of fumaric acid using in-vitro and in-vivo assays. Moreover, safety study was also done.Materials and methods: The 0.1 ml complete Freund’s adjuvant was injected in left hind paw in all Wistar rats except normal rats at day 1 to induced arthritis. The treatment with fumaric acid at 10, 20, 40, and fumaric acid 40 mg/kg together with methotrexate (MTX) was administered to immunized rats at 8th day via oral gavage and continued till 28th day though, MTX was administered as standard control.Results: The fumaric acid notably (p < 0.0001) lessened the paw edema and arthritic scoring, reinstated body and immune organ weight, and oxidation status in treated rats. Fumaric acid notably restored altered C-reactive protein, rheumatoid factor, liver function tests, ESR, WBCs, RBCs and Hb levels in treated rats. The fumaric acid in combination noticeably (p < 0.01–0.0001) suppressed the expression of TNF- α, IL-6, IL-1β, NF-kβ, and COX-2, and over expressed IL-4, and IL-10 in contrast to other treated groups. Fumaric acid had presented a dose-dependent antioxidant, anti-inflammatory and anti-arthritic activities while notable activity exhibited by fumaric acid in combination with MTX. The fumaric acid exhibited non-significant clinical signs of toxicity and mortality in acute toxicity study. The LD50 was more than 2000 mg/kg.Conclusion: Fumaric acid in combination can be used as disease-modifying anti-rheumatic drug but it will need extensive pre-clinical and clinical studies. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This investigation focuses on the prevalent continental oil shale within the Triassic Chang 7, a member of the Yanchang Formation in the Ordos Basin and the Permian Lucaogou Formation in the Junggar Basin of western China, and delves into the impacts of hydrocarbon generation and the derived organic acids on the physical attributes of oil shale reservoirs. Water-soluble organic acids (WSOAs) were extracted via Soxhlet extraction and analyzed by a 940 ion chromatograph (Metrohm AG), supplemented with core observations, thin-section analyses, pyrolysis, and trace element assays, as well as the qualitative observation of pore structures via FIB-SEM scanning electron microscopy. The study discloses substantial disparities in the types and abundances of organic acids within the oil shale strata of the two regions, with mono-acids being conspicuously more prevalent than dicarboxylic acids. The spatial distribution of organic acids within the oil shale strata in the two regions is non-uniform, and their generation is inextricably correlated with the type of organic matter, thermal maturity, and depth at which they are buried. During diverse stages of diagenesis, the hydrocarbons and organic acids produced from the pyrolysis of organic matter not only exert an impact on the properties of pore fluids but also interact with diagenetic processes such as compaction, dissolution, and metasomatism to enhance the reservoir quality of oil shale. The synergy between chemical interactions and physical alterations collectively governs the migration and distribution patterns of organic acids as well as the characteristics of oil shale reservoirs. Furthermore, the sources of organic acids within the oil shale series in the two regions demonstrate pronounced dissimilarities, which are intimately associated with the peculiarities of their sedimentary milieu. The oil shale of the Yanchang Formation was formed in a warm and humid freshwater lacustrine basin environment, while the oil shale of the Lucaogou Formation was deposited in a brackish to saline lacustrine setting under an arid to semi-arid climatic regime. These variances not only illuminate the intricacy and multiplicity of the sedimentary attributes of oil shale but also accentuate the impact of the sedimentary environment on the genesis and distribution of organic acids, especially the transformation and optimization of reservoir dissolution by organic acids generated during hydrocarbon generation—a factor of paramount significance for the precise identification and effective development of the "sweet spot" area of shale oil. These areas, characterized by an abundance of organic matter, their maturity, and superior reservoir properties, are the foci of the efficient exploration and development of continental shale oil. [ABSTRACT FROM AUTHOR]

Polyurethane (PU) stands out as a crucial category of polymers which have become indispensable in improving our quality of life, revolutionizing various aspects of human existence. However, this convenience comes with a dark side – the environmental impact associated with its disposal. Nevertheless, recycling presents a promising solution, aligning with the principles of a circular economy by transforming polymer waste into new materials. A notable focus within this realm is the utilization of dicarboxylic acids (DA) as depolymerization agents, achieved through a process known as acidolysis. This method has proven to be an exceptional solution, primarily explored for recycling PU foams and subsequently employed in the production of new foams. The resulting recycled polyol finds successful applications in various PU products, including rigid and flexible foams, adhesives, and coatings. Analyzing the impact of recycled polyol on the properties of new PU products reveals interesting insights. While it slightly affects the morphology and color of foams, there is no significant impact on density or thermal conductivity. Notably, flexible foams exhibit increased stiffness when produced using recycled polyol. Additionally, the strength of PU adhesives and the surface hardness of PU coatings are enhanced with the incorporation of recycled polyol, albeit with a reduction in gloss. The recycled PU coatings also display a more hydrophobic surface. Considering both environmental and economic benefits, the advantages of this approach are evident. With the aim of catering to the needs of both the academic and industrial sectors, this review delves into the subject of PU recycling via acidolysis, subsequently exploring the utilization of recycled materials in the creation of new PU products. The review offers an in-depth explanation of the acidolysis process and thoroughly examines the degradation mechanisms involved. Additionally, it scrutinizes the impact of reaction conditions on the properties of the recycled materials and investigates their applicability in the production of novel materials. Moreover, the review presents an analysis of the environmental and economic implications associated with these processes. In summary, this review overviews the current status of acidolysis of PU and prospects for its future. [ABSTRACT FROM AUTHOR]

Traditional polyamide elastomer synthesis via polycondensation of diamines and dicarboxylic acids involves high energy use and by‐product mass loss. Here, we present a novel method using thiol‐Michael addition click chemistry to produce these elastomers under mild conditions, marking the first use of this strategy. The polymerization involves coupling bis‐acrylamide (BAA) with 3,6‐dioxa‐1,8‐octanedithiol (DODT), catalyzed by 1,5‐diazabicyclo[4.3.0]non‐5‐ene (DBN). BAA is synthesized from polyetheramine and acryloyl chloride, creating a compound with amide groups and carbon double bonds at chain ends. These double bonds' electron‐withdrawing effect facilitates the click reaction efficiently, avoiding high energy and mass loss. The resulting polymers have a molecular weight of approximately 10,000 g/mol, verified by 1H NMR and FTIR spectroscopy, which show amide group presence. SAXS and AFM confirm nanophase separation of these groups. Tensile strength ranges from 0.235 to 0.542 MPa, decreasing with lower polyetheramine content but still showing notable elasticity. This method's low energy use, no mass loss, and good mechanical properties make it promising for developing high‐performance polyamide plastics and elastomers, appealing to researchers in both academia and industry. Highlights: High elasticity, softness, and high tensile polyamide elastomer.Thiol‐Michael addition click reaction conforms to atomic economy.Long molecular chain contains extraordinary evolution of hydrogen bonding. [ABSTRACT FROM AUTHOR]

The utilization of biomass resources in the production of bio‐based or bio‐recycled polyurethanes (PUs) enhances the sustainable development and eco‐friendliness of PU. Herein, a series of new bio‐based aliphatic poly(propylene dicarboxylate) diols were synthesized using bio‐based 1,3‐propanediol (bio‐PDO) and aliphatic dicarboxylic acids with different chain lengths. These bio‐based polyester diols and 1,4‐butanediol (BDO) reacted with 4,4′‐dicyclohexylmethane diisocyanate to produce aliphatic PU elastomers (PUEs). The study aimed to evaluate the impact of the structure of poly(propylene dicarboxylate) diols on the architecture, morphology, mechanical properties, and degradation of PUEs, thereby expanding the application of bio‐PDO. The results indicate a strong correlation between the degree of microphase separation, tensile properties, and degradation behavior of the synthesized PUEs and the number of methylene groups in the repeating unit of the poly(propylene dicarboxylate) diols. Notably, the PUE derived from poly(propylene pimelate) diol demonstrates the highest level of microphase separation and superior elasticity properties because of the high flexibility of the polyester. On the other hand, PUE prepared from poly(propylene succinate) diol exhibits the fastest degradation performance due to its high density of ester groups. Bio‐PDO based polyester diols show significant potential as raw materials for PUEs with biodegradable and adjustable mechanical properties. Highlights: Poly(propylene dicarboxylate) diols were prepared from bio‐based 1,3‐propanediol.The poly(propylene dicarboxylate) diols based polyurethane elastomers (PUEs) have high tensile strength (>22 MPa) and elongation at break (>920%).The morphology, mechanical properties and degradation of PUEs are highly related to the structure of the poly(propylene dicarboxylate) diols.The increasing repeating unit length of the poly(propylene dicarboxylate) diols increases elastic recovery of PUEs. [ABSTRACT FROM AUTHOR]

The composition of aerosols influenced by regional pollution sources during a post-monsoon haze event was studied including the isotopic, bulk, and molecular signatures. The air mass back trajectory and fire spot analysis revealed that the Delhi aerosols were influenced by the regional post-harvest crop (rice plant) residue-burning activities during the sampling period. To better understand the atmospheric processes during such an event, three samples of 4 h duration each (Period I: from 06:00–10:00, Period II: 10:00–14:00, and Period III: 14:00–18:00 h local time) were collected during the sampling period (8th -17th November, 2019) in the daytime. The average mass concentration of PM2.5, molecular compounds including the inorganic and carbonaceous components (dicarboxylic acid class compounds), along with the stable isotopes of C and N were observed to be elevated during Period I of the study. NH4+ and SO42− were found to be the most abundant inorganic ions during Period II and III with Cl− being the dominant ion during Period I. The OC/EC, WSOC/EC ratios indicated the influence of biomass burning on Delhi aerosols with little influence of local ageing processes evident from the minimal variation observed between the three periods of study during the day. High concentrations of dicarboxylic acids than previous studies are reported with oxalic and succinic acid being the most abundant diacids, a typical behaviour observed in biomass-burning influenced aerosols with an interesting observation of terephthalic acid to be found in an appreciable amount. The δ15 N of TN and δ13 C of TC signatures clearly indicated the influence of emissions from the burning of a C3 plant on the aerosols. The results strongly suggested that the aerosols were influenced by biomass-burning activities in the neighbouring regions and were aged during the atmospheric transport over to the city of Delhi with minimal effect of local ageing processes during the study period. [ABSTRACT FROM AUTHOR]

Zinc metal–organic frameworks have emerged as promising candidates, demonstrating excellent biological properties stemming from the unique characteristics of MOFs and zinc. In this study, we employed a facile method to synthesize a zinc metal–organic framework [Zn(IP)(H2O)] using ultrasound irradiation, with the linker being isophthalic acid (IPA) (1,3-benzene dicarboxylic acid). The parent Zn-MOF and two Ag/Zn-MOF samples prepared via loading and encapsulation methods were comprehensively characterized using various techniques, including FT-IR, XRD, SEM, TEM, N2 adsorption–desorption isotherm, UV–vis spectroscopy and TGA. The parent Zn-MOF and two Ag/Zn-MOF samples exhibited a broad spectrum of antibacterial effects. Remarkably, genomic DNA of P. aeruginosa was effectively degraded by Zn-MOF, further supporting its potent antibacterial results. The free radical inhibition assay demonstrated a 71.0% inhibition under the influence of Zn-MOF. In vitro cytotoxicity activity of Zn-MOF against HepG-2 and Caco-2 cell lines revealed differential cytotoxic effects, with higher cytotoxicity against Caco-2 as explored from the IC50 values. This cytotoxicity was supported by the high binding affinity of Zn-MOF to CT-DNA. Importantly, the non-toxic property of Zn-MOF was confirmed through its lack of cytotoxic effects against normal lung cell (Wi-38). The anti-inflammatory treatment of Zn-MOF achieved 75.0% efficiency relative to the standard Ibuprofen drug. DFT and docking provided insights into the geometric stability of Zn-MOF and its interaction with active amino acids within selected proteins associated with the investigated diseases. Finally, the synthesized Zn-MOF shows promise for applications in cancer treatment, chemoprevention, and particularly antibacterial purposes. [ABSTRACT FROM AUTHOR]

Electrochemical biomass oxidation coupled with hydrogen evolution offers a promising route to generate value‐added chemicals and clean energy. The complex adsorption behavior of 5‐hydroxymethyl furfural (HMF) and hydroxyl ions (OH−) on the electrocatalyst surface during HMF electrooxidation reaction (HMFOR) necessitates an in‐depth understanding of active sites available for adsorption. Herein, oxygen vacancy (VO) defects are introduced in NiFe layered double hydroxide (LDH) using Ce dopants to manipulate electronic structure. Synchrotron‐based HE‐XRD and XAS indicate negligible VO in La‐doped NiFe while Ce doping leads to VO defects due to flexible Ce redox (Ce3+↔ Ce4+). The VO‐rich Ce‐NiFe exhibits higher Faradic efficiency of ≈90% to produce 2,5‐furan dicarboxylic acid (FDCA), far greater than ≈60% for NiFe VO in Ce‐NiFe act as alternative active sites for OH− adsorption, hence reducing adsorption competition for the same metal sites. DFT calculation results corroborate experimental findings by showcasing that the presence of VO in Ce‐NiFe manipulates the adsorption energies and facilitates the chemical adsorption OH− in VO to improve HMFOR. In situ HE‐XRD derived pair distribution function coupled to RMC simulations confirm OH− trapping in VO and HMF adsorption on metal centers as evident by interlayer distance evolution. Taken together, this work showcases routes for dual‐site electrocatalyst design for improved biomass electrooxidation. [ABSTRACT FROM AUTHOR]

Alumoxanes are typically produced via controlled hydrolysis of short‐chain alkyl aluminium compounds which leads to oligomeric species that are usually difficult to obtain in crystalline form. Simultaneously, various alternative non‐hydrolytic approaches to alumoxanes have also been used. In this work, we report on a new methylalumoxane scaffold derived from the alkylation of a series of dicarboxylic acids: itaconic acid (HO2CCH2C(=CH2)CO2H), succinic acid (HO2CCH2CH2CO2H) and homophthalic acid (HO2CCH2C6H4CO2H). The reactions of AlMe3 with a selected dicarboxylic acid in the molar ratio 4 : 1 conducted at elevated temperature occur with double methylation of each carboxylic group and provide to the formation of a new methylalumoxane aggregate, Me10Al6O4, flanked by methylaluminium diolate units. We also aimed to obtain dialkylaluminium derivatives of dicarboxylic acids by the controlled reaction of the appropriate acid with AlMe3 in the 1 : 2 stoichiometry. While the synthesis of organoaluminium derivatives of flexible aliphatic dicarboxylic acids (itaconic and succinic acids) is challenging due to their insolubility, the related homophtalate compound readily forms a molecular tetranuclear cluster, [([(O2CCH2C6H4CO2)(μ‐AlMe2)2]2. The molecular and crystal structures of the resulting compounds were determined via NMR spectroscopic analysis and single crystal X‐ray diffraction crystallography. [ABSTRACT FROM AUTHOR]

Background: Esophageal diseases (ED) are a kind of common diseases of upper digestive tract. Previous studies have proved that metabolic disorders are closely related to the occurrence and development of ED. However, there is a lack of evidence for causal relationships between metabolites and ED, as well as between metabolite ratios representing enzyme activities and ED. Herein, we explored the causality of genetically determined metabolites (GDMs) on ED through Mendelian Randomization (MR) study. Methods: Two-sample Mendelian randomization analysis was used to assess the causal effects of genetically determined metabolites and metabolite ratios on ED. A genome-wide association analysis (GWAS) encompassing 850 individual metabolites along with 309 metabolite ratios served as the exposures. Meanwhile, the outcomes were defined by 10 types of ED phenotypes, including Congenital Malformations of Esophagus (CME), Esophageal Varices (EV), Esophageal Obstructions (EO), Esophageal Ulcers (EU), Esophageal Perforations (EP), Gastroesophageal Reflux Disease (GERD), Esophagitis, Barrett's Esophagus (BE), Benign Esophageal Tumors (BETs), and Malignant Esophageal Neoplasms (MENs). The standard inverse variance weighted (IVW) method was applied to estimate the causal relationship between exposure and outcome. Sensitivity analyses were carried out using multiple methods, including MR-Egger, Weighted Median, MR-PRESSO, Cochran's Q test, and leave-one-out analysis. P < 0.05 was conventionally considered statistically significant. After applying the Bonferroni correction for multiple testing, a threshold of P < 4.3E-05 (0.05/1159) was regarded as indicative of a statistically significant causal relationship. Furthermore, metabolic pathway analysis was performed using the web-based MetaboAnalyst 6.0 software. Results: The findings revealed that initially, a total of 869 candidate causal association pairs ( P ivw < 0.05) were identified, involving 442 metabolites, 145 metabolite ratios and 10 types of ED. However, upon applying the Bonferroni correction for multiple testing, only 36 pairs remained significant, involving 28 metabolites (predominantly lipids and amino acids), 5 metabolite ratios and 6 types of ED. Sensitivity analyses and reverse MR were performed for these 36 causal association pairs, where the results showed that the pair of EV and 1-(1-enyl-palmitoyl)-2-linoleoyl-GPE (p-16:0/18:2) did not withstand the sensitivity tests, and Hexadecenedioate (C16:1-DC) was found to have a reverse causality with GERD. The final 34 robust causal pairs included 26 metabolites, 5 metabolite ratios and 5 types of ED. The involved 26 metabolites predominantly consisted of methylated nucleotides, glycine derivatives, sex hormones, phospholipids, bile acids, fatty acid dicarboxylic acid derivatives, and N-acetylated amino acids. Furthermore, through metabolic pathway analysis, we uncovered 8 significant pathways that played pivotal roles in five types of ED conditions. Conclusions: This study integrated genomics with metabolomics to assess causal relationships between ED and both metabolites and metabolite ratios, uncovering several key metabolic features in ED pathogenesis. These findings have potential as novel biomarkers for ED and provide insights into the disease's etiology and progression. However, further clinical and experimental validations are necessary [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Developing non‐noble metal catalysts that can efficiently and selectively hydrogenate arenes remains a significant challenge. In this study, we developed efficient Ni catalysts for the arene hydrogenation based on an organic acid‐regulated impregnation strategy. These easily accessible Ni catalysts demonstrated exceptional efficiency, selectivity, reusability, and good substrate compatibility. The influence of carbon chain lengths and side‐chain hydroxyl or amino groups on dicarboxylic acids used in the catalyst preparation was comprehensively investigated. Characterizations and kinetic studies demonstrated the influence of organic acids on the size of Ni nanoparticles, the proportion of metallic nickel, and the strength of surface acidity. These factors influenced the activation of arene and hydrogen, thereby affecting the hydrogenative activity. Notably, hydroxyapatite‐supported Ni catalyst, assisted by tartaric acid (Ni‐TA/HAP) with an appropriate tartaric acid‐to‐nickel ratio, resulted in relatively smaller Ni nanoparticles, an increased proportion of Ni0, and more acidic sites, thereby exhibiting the best hydrogenation performance. [ABSTRACT FROM AUTHOR]

Succinic acid (SA), a dicarboxylic acid of industrial importance, can be efficiently produced by metabolically engineered Mannheimia succiniciproducens. Although the importance of magnesium (Mg2+) ion on SA production has been evident from our previous studies, the role of Mg2+ ion remains largely unexplored. In this study, we investigated the impact of Mg2+ ion on SA production and developed a hyper-SA producing strain of M. succiniciproducens by reconstructing the Mg2+ ion transport system. To achieve this, optimal alkaline neutralizer comprising Mg2+ ion was developed and the physiological effect of Mg2+ ion was analyzed. Subsequently, the Mg2+ ion transport system was reconstructed by introducing an efficient Mg2+ ion transporter from Salmonella enterica. A high-inoculum fed-batch fermentation of the final engineered strain produced 152.23 ± 0.99 g/L of SA, with a maximum productivity of 39.64 ± 0.69 g/L/h. These findings highlight the importance of Mg2+ ions and transportation system optimization in succinic acid production by M. succiniciproducens. [ABSTRACT FROM AUTHOR]

Two fluorescent Zn(II) polymers (1 and 2) with different dicarboxylic acid co-ligands have been obtained under hydrothermal reaction conditions. In 1 and 2, the flexible bmb adopts two trans-conformations with different Ndonor···N–Csp3···Csp3 torsion angles, generating 3-D interspersed (412·63)-pcu grids. The dicarboxylic acid co-ligands influence the conformation of bmb, which lead to diverse spatial structures from a single helix to a 2-D lattice network. Photoluminescence investigations reveal that 1 has a redshift compared with o-H2oba (4,4'-oxydibenzoic acid) and 2 has a blueshift of 20 nm compared with H2bpdc ([1,1'-biphenyl]-4,4'-dicarboxylic acid), which can be attributed to a ligand-centered charge transfer. [ABSTRACT FROM AUTHOR]

Ferrous oxalate dihydrate is a versatile organic mineral with applications across fields. However, little is known about the feasibility of its synthesis directly from iron-bearing minerals using binary subcritical water (sCW) systems and its associated kinetics. In this study, the sCW+oxalic acid system at either 115 °C or 135 °C was investigated as a reaction medium for ferrous oxalate dihydrate (α-FeC2O4∙2H2O) synthesis, starting from ferrotitaniferous sands. The kinetics of the synthesis reaction were studied, and the physicochemical characterization of the as-synthetized ferrous oxalates was performed. Overall, the sCW synthesis was temperature-dependent, following second-order reaction kinetics according to the proposed precipitation pathway. A high reaction rate constant, significantly high yields (up to 89%), and reduced reaction times (2–8 h) were evident at 135 °C. The as-synthetized product corresponded to the monoclinic α-FeC2O4∙2H2O, showed relatively high specific surface areas (from 31.9 to 33.7 m2∙g−1), and exhibited band gap energies within the visible light range (~2.77 eV). These results suggest that α-FeC2O4∙2H2O can be synthesized using an organic dicarboxylic acid and iron-rich, widely available, low-cost mineral precursors. In addition, the as-prepared α-FeC2O4∙2H2O could be further optimized and tested for catalytic and visible light photocatalytic applications. [ABSTRACT FROM AUTHOR]

Two copper(II) mixed ligand complexes with dicarboxylate bridges were prepared and studied, namely [Cu2(μ-fu)(pmdien)2(H2O)2](ClO4)2 (complex No. 5) and [Cu2(μ-dtdp)(pmdien)2(H2O)2](ClO4)2 (complex No. 6), where H2fu = fumaric acid, pmdien = N,N,N′,N″,N″ pentamethyldiethylenetriamine, and H2dtdp = 3,3′-dithiodipropionic acid. The copper atoms are coordinated in the same mode by the tridentate pmdien ligand and oxygen of water molecules, and they only differ in the dicarboxylate bridge. This work is focused on the study of the inhibitory effect of these potential antimicrobial drugs on the activity of the most important human liver drug-metabolizing enzymes, cytochromes P450 (CYP), especially their forms CYP2C8, CYP2C19, and CYP3A4. The obtained results allow us to estimate the probability of potential drug interactions with simultaneously administrated drugs that are metabolized by these CYP enzymes. In conclusion, the presence of adverse effects due to drug–drug interactions with concomitantly used drugs cannot be excluded, and hence, topical application may be recommended as a relatively safe approach. [ABSTRACT FROM AUTHOR]

The 3-ketoacyl-CoA thiolase is the rate-limiting enzyme for linear dicarboxylic acids production. However, the promiscuous substrate specificity and suboptimal catalytic performance have restricted its application. Here we present both biochemical and structural analyses of a high-efficiency 3-ketoacyl-CoA thiolase Tfu_0875. Notably, Tfu_0875 displayed heightened activity and substrate specificity for succinyl-CoA, a key precursor in adipic acid production. To enhance its performance, a deep learning approach (DLKcat) was employed to identify effective mutants, and a computational strategy, known as the greedy accumulated strategy for protein engineering (GRAPE), was used to accumulate these effective mutants. Among the mutants, Tfu_0875N249W/L163H/E217L exhibited the highest specific activity (320% of wild-type Tfu_0875), the greatest catalytic efficiency (kcat/KM = 1.00 min-1 mM-1 ), the highest succinyl-CoA specificity (KM = 0.59 mM, 28.1% of Tfu_0875) and dramatically reduced substrate binding energy (− 30.25 kcal mol-1 v.s. -15.94 kcal mol−1 ). A structural comparison between Tfu_0875N249W/L163H/E217L and the wild type Tfu_0875 revealed that the increased interaction between the enzyme and succinyl-CoA was the primary reason for the enhanced enzyme activity. This interaction facilitated rapid substrate anchoring and stabilization. Furthermore, a reduced binding pocket volume improved substrate specificity by enhancing the complementarity between the binding pocket and the substrate in stereo conformation. Finally, our rationally designed mutant, Tfu_0875N249W/L163H/E217Lincreased the adipic acid titer by 1.35-fold compared to the wild type Tfu_0875 in shake flask. The demonstrated enzymatic methods provide a promising enzyme variant for the adipic acid production. The above effective substrate binding pocket engineering strategy can be beneficial for the production of other industrially competitive biobased chemicals when be applied to other thiolases. [ABSTRACT FROM AUTHOR]

A novel Ni (II) coordination polymer [Ni(pdc)(bib)(H2 O)]n (Ni-CP) was synthesised by solvothermal method with 3,5-pyridyl dicarboxylic acid (3,5-H2 pdc), 1, 4-bis (1-imidazolyl) benzene (bib) and Ni(NO3)2, and characterized by single-crystal X-ray diffraction, powder X-ray diffraction, thermogravimetric, IR spectroscopic and fluorescence spectroscopy analysis. The results show that Ni-CP crystallized as a monoclinic system with C2/c space group. The asymmetric unit of Ni-CP was comprised of one Ni(II), two half bib ligands, one completely deprotonated 3,5-pdc2 - ligands and one coordinated water molecule. The environment around central Ni(II) can be described as irregular hexacoordination octahedral geometry of NiO3 N3. The bib and 3,5-pdc2 - ligands were bridged by the bidentate coordination mode in the μ2-η1∶η1 fashion and the tridentate coordination mode in the μ3-η1∶η1∶η1 fashion to form a three-dimensional network framework. From a topological point of view, the two-dimensional frame structure can be simplified to a 3-connected topology with a Schläfli symbol (4·82). We consider the 3,5-pdc2 - ligands and Ni(II) as nodes and the bib ligands as connectors, forming a threedimensional structure can be simplified to a 3,5-connected double nodes with topological symbols (4·6·8)(4·62 ·87). The porosity of Ni-CP is 17. 4%. Ni-CP could selectively detect Fe3 +, CrO2 - 4 and Cr2 O2 - 7 with detection limits of 4. 275 ×10 -5, 2. 681 ×10 -5, 2. 681 ×10 -5 mol/L, respectively, and have a high quenching rate. [ABSTRACT FROM AUTHOR]

Dicarboxylic acids (DCAs) are major players in the formation of secondary organic aerosols (SOAs) and climate change. DCAs have potential impact on human health and environmental issues ranging from local scale to global scale participate mainly in the cloud condensation. In this context, oxalic acid (OA) and malonic acid (MA) are the most dominant DCAs in the atmosphere. A full atmospheric degradation mechanism of OA and MA with the most reactive tropospheric oxidants, namely, OH, Cl and NO3 radicals, were studied using M06‐2X, ωB97XD/cc‐pVTZ and 6‐311++G(2df,2p) level of theories. To evaluate the atmospheric influence, this study enables us to deep investigation of fate of OA and MA with respect to the mentioned radicals and their subsequent secondary reactions. The latter result in the formation of carbon dioxide (CO2), formic acid (HCOOH), which contributes to the formation of SOA and climate change. The reaction mechanism in this study was initiated through H‐abstraction reaction, followed by dehydrogenation and decarboxylation reaction of both DCAs. The rate coefficients of OA, MA with OH, Cl and NO3 radicals are determined theoretically using variational transition state theory (VTST) with Eckart tunnelling method in the temperature range of 278–1000 K. At 298 K, the rate coefficient of OA with OH, Cl and NO3 are 2.48 × 10−15, 2.37 × 10−20, 6.16 × 10−23 in cm3 molecule−1 s−1, whereas MA with OH, Cl and NO3 are 9.76 × 10−14, 1.01 × 10−12 and 5.89 × 10−18 in cm3 molecule−1 s−1, respectively. Our present results shed light on the atmospheric implications of two DCAs and provide the significant insight for the atmospheric pathways. [ABSTRACT FROM AUTHOR]

[Display omitted] Photocatalytic nitrogen fixation is seen to be a potential technology for nitrogen reduction due to its eco-friendliness, low energy consumption, and environmental protection. In this study, photocatalysts with abundant oxygen vacancies (Zr-naphthalene dicarboxylic acid (Zr-NDC) and Zr-phthalic acid (Zr-BDC)) were designed using 1,4-naphthalene dicarboxylic acid (H 2 NDC) and 1,4-phthalic acid (H 2 BDC) as ligands. Since the structure of H 2 NDC includes one extra benzene ring than H 2 BDC, the charge density differential of the organic ligand is probably altered. The hypothesis is proved by density function theory (DFT) calculation. The abundant oxygen vacancies of the catalyst offer numerous active sites for nitrogen fixation. Concurrently, the process of ligand–metal charge transfer facilitates photo-electron transfer, creating an active center for nitrogen reduction. Additionally, the functionalization of ligand amplifies another pathway for charge transfer, broadening the light absorption range of Metal-organic framework (MOF) and increasing its capacity for nitrogen reduction. In contrast to H 2 BDC, the benzene ring added in H 2 NDC structure acts as an electron energy storage tank with a stronger electron density difference favorable for photogenerated electron-hole separation resulting in higher photocatalytic activity in Zr-NDC. The experimental results show that the nitrogen fixation efficiency of Zr-NDC is 163.7 µmol g−1h−1, which is significantly better than that of Zr-BDC (29.3 µmol g−1h−1). This work utilizes cost-effective and non-toxic ingredients to design highly efficient photocatalysts, thereby significantly contributing to the practical implementation of green chemistry principles. [ABSTRACT FROM AUTHOR]

We introduce a novel dual redox mediator synthesized by covalently linking ferrocene dicarboxylic acid (FcDA) and thionine (TH) onto a pre-treated glassy carbon electrode. This unique structure significantly enhances the electro-oxidation of dopamine (DA) and the reduction of hydrogen peroxide (H2O2), offering a sensitive detection method for both analytes. The electrode exhibits exceptional sensitivity, selectivity, and stability, demonstrating potential for practical applications in biosensing. It facilitates rapid electron transfer between the analyte and the electrode surface, detecting H2O2 concentrations ranging from 1.5 to 60 µM with a limit of detection (LoD) of 0.49 µM and DA concentrations from 0.3 to 230 µM with an LoD of 0.07 µM. The electrode's performance was validated through real-sample analyses, yielding satisfactory results. [ABSTRACT FROM AUTHOR]

Aldehyde dehydrogenases (ALDHs) represent a superfamily of enzymes, which oxidize aldehydes to the corresponding acids. Certain families, namely ALDH9 and ALDH10, are best active with ω-aminoaldehydes arising from the metabolism of polyamines such as 3-aminopropionaldehyde and 4-aminobutyraldehyde. Plant ALDH10s show broad specificity and accept many different aldehydes (aliphatic, aromatic and heterocyclic) as substrates. This work involved the above-mentioned aminoaldehydes acylated with dicarboxylic acids, phenylalanine, and tyrosine. The resulting products were then examined with native ALDH10 from pea and recombinant ALDH7s from pea and maize. This investigation aimed to find a common efficient substrate for the two plant ALDH families. One of the best natural substrates of ALDH7s is aminoadipic semialdehyde carrying a carboxylic group opposite the aldehyde group. The substrate properties of the new compounds were demonstrated by mass spectrometry of the reaction mixtures, spectrophotometric assays and molecular docking. The N-carboxyacyl derivatives were good substrates of pea ALDH10 but were only weakly oxidized by the two plant ALDH7s. The N-phenylalanyl and N-tyrosyl derivatives of 3-aminopropionaldehyde were good substrates of pea and maize ALDH7. Particularly the former compound was converted very efficiently (based on the kcat/Km ratio), but it was only weakly oxidized by pea ALDH10. Although no compound exhibited the same level of substrate properties for both ALDH families, we show that these enzymes may possess more common substrates than expected. [ABSTRACT FROM AUTHOR]

Background: Numerous research studies have indicated a possible association between type 2 diabetes (T2DM) and gut microbiota. To explore specific metabolic pathways connecting gut microbiota and T2DM, we employed Mendelian randomization (MR) and linkage disequilibrium score regression (LDSC) techniques. Methods: This research utilized data from genome-wide association studies (GWAS) that are publicly accessible. We evaluated the genetic correlation between gut microbiota and T2DM using LDSC. Causality was primarily determined through the inverse variance weighted (IVW) method. To verify the robustness of our results, we conducted sensitivity analyses using several approaches, including the weighted median, MR-Egger, and MR-PRESSO. We integrated summary effect estimates from LDSC, along with forward and reverse MR, into a meta-analysis for T2DM using various data sources. Additionally, mediation analysis was performed to explore the impact of plasma metabolites on the relationship between gut microbiota and T2DM. Results: Our study indicated a significant genetic correlation between genus RuminococcaceaeUCG005 (Rg = -0.26, Rg_;P = 2.07 x 10-4) and T2DM. Moreover, the forward MR analysis identified genus RuminococcaceaeUCG010 (OR = 0.857, 95% CI 0.795, 0.924; P = 6.33 x 10-5) and order Clostridiales (OR = 0.936, 95% CI 0.878, 0.997; P = 0.039) as being significantly associated with a decreased risk of T2DM. The analysis also highlighted several plasma metabolites as significant mediators in these relationships, with metabolites like octadecadienedioate (C18:2-DC) and branched chain 14:0 dicarboxylic acid being notably involved. Conclusion: The findings demonstrate a significant impact of gut microbiota on T2DM via plasma metabolites, suggesting potential metabolic pathways for therapeutic targeting. This study enhances our understanding of the microbiota's role in T2DM pathogenesis and supports the development of microbiota-based interventions. [ABSTRACT FROM AUTHOR]

Cinnamomum tamala leaf (CTL), also known as Indian bay leaf, is used all over the world for seasoning, flavoring, and medicinal purposes. These characteristics could be explained by the presence of several essential bioactive substances and lipid derivatives. In this work, rapid screening and identification of the chemical compounds in supercritical (SC)-CO2 extracts of CTL by use of UPLC-Q-TOF-MSE with a multivariate statistical analysis approach was established in both negative and positive mode. A total of 166 metabolites, including 66 monocarboxylic fatty acids, 52 dicarboxylic fatty acids, 27 fatty acid amides, and 21 cinnamic acid derivatives, were tentatively identified based on accurate mass and the mass spectrometric fragmentation pattern, out of which 142 compounds were common in all SC-CO2 extracts of CTL. Further, PCA and cluster hierarchical analysis clearly discriminated the chemical profile of analyzed extracts and allowed the selection of SC-CO2 extract rich in fatty acids, fatty acid amides, and other bioactive constituents. The result showed that the higher number of compounds was detected in CTL4 (300 bar/55 °C) extract than the other CTL extracts. The mono- and di-carboxylic fatty acids, fatty acid amides, and cinnamic acid derivatives were identified in CTL for the first time. UPLC-Q-TOF-MSE combined with chemometric analysis is a powerful method to rapidly screen the metabolite profiling to justify the quality of CTL as a flavoring agent and in functional foods. [ABSTRACT FROM AUTHOR]