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The influence of UV-Vis and monochromatic radiation (λ = 408 nm) on the reactions of copper sulfate (CuSO4) and copper(II) oxide (CuO) with β-diketones, chelators, and dicarboxylic acids was studied. The reactions of CuSO4 and CuO with Trilon B and succinic acid in aqueous media in the presence of urea occurred faster by using UV-Vis radiation. UV radiation accelerated the reaction of CuSO4 with H4edta in aqueous MeCN. Monochromatic radiation hastened the reaction of CuO with Trilon B and H4edta in aqueous and MeCN media. Eight reactions that were significantly accelerated by electromagnetic radiation were found. [ABSTRACT FROM AUTHOR]

The Halopseudomonas species, formerly classified as Pseudomonas pertucinogena lineage, form a unique phylogenetic branch within the Pseudomonads. Most strains have recently been isolated from challenging habitats including oil‐ or metal‐polluted sites, deep sea, and intertidal zones, suggesting innate resilience to physical and chemical stresses. Despite their comparably small genomes, these bacteria synthesise several biomolecules with biotechnological potential and a role in the degradation of anthropogenic pollutants has been suggested for some Halopseudomonads. Until now, these bacteria are not readily amenable to existing cultivation and cloning methods. We addressed these limitations by selecting four Halopseudomonas strains of particular interest, namely H. aestusnigri, H. bauzanensis, H. litoralis, and H. oceani to establish microbiological and molecular genetic methods. We found that C4‐C10 dicarboxylic acids serve as viable carbon sources in both complex and mineral salt cultivation media. We also developed plasmid DNA transfer protocols and assessed vectors with different origins of replication and promoters inducible with isopropyl‐β‐d‐thiogalactopyranoside, l‐arabinose, and salicylate. Furthermore, we have demonstrated the simultaneous genomic integration of expression cassettes into one and two attTn7 integration sites. Our results provide a valuable toolbox for constructing robust chassis strains and highlight the biotechnological potential of Halopseudomonas strains. [ABSTRACT FROM AUTHOR]

3D-printing has gained popularity in recent years due to the many advantages it offers over the traditional approaches for instance this technology reduces the time a dentist needs to create and fit dentures to just 2–3 sessions. Fumaric, maleic, and adipic acids with the percentage (0.1 wt.%) were added to chitosan solution (2 wt.%) and the final composite was added to the 3D printable acrylic resin. The specimens were examined for several chemical analyses (XRD, SEM, FTIR) and mechanical tests (impact strength and surface hardness tests), where the total number (115) of specimens used in the study was specimens divided into five groups. In chemical analysis, one specimen was constructed for each modified group and one specimen was used as the control group (3d printable resin without addition (non-modified) for each test. For mechanical tests ten specimens were constructed for each modified group and ten specimens were used as the control group (3d printable resin without addition (non-modified) for each test. The results of chemical analysis showed improvement in the properties of modified 3d printable acrylic denture base resin, additionally the mechanical test results showed that the (Fumaric acid and Maliec acid with Chitosan) specimens have the highest properties in comparison with other specimens, while the lowest properties were for specimens of 3D printable acrylic resin with chitosan. The chemical and mechanical properties of the modified 3D-printed denture base are improved when chitosan is modified with dicarboxylic acids. Conversely, if chitosan alone is used to modify the 3D-printed polymers, the mechanical and chemical properties would be decreased. [ABSTRACT FROM AUTHOR]

Superior single crystal of 1,2-benzene dicarboxylic acid anhydride additionally called Phthalic anhydride (PAN) was developed via solution growth at low temperatures. Single crystal X-ray diffraction investigation revealed the crystal system and unit cell characteristics. The phase stability and crystalline nature were uncovered by powder X-ray diffraction analysis. FT-IR examination was done for the titular material so as to survey the various functional groups. With the use of the VEDA program's relevant resources, vibrational assignments have been made on the concept of Potential Energy Distribution (PED). Density Functional Theory (DFT) was employed to smooth out the molecular structure of PAN and was additionally utilized to consider FT-IR spectrum at molecular level. Non covalent interactions reduced density gradient (NCI-RDG) analysis has been used for the prediction of the weak interaction in the actual space in terms of the electron density along with its derivatives for PAN. Atoms in Molecules (AIM) analysis was carried for out for PAN. The docking research of the small molecule (PAN) with target protein confirmed that this is a great molecule which docks nicely with numerous targets associated with Hypoxia Inducible Factor 1-a. The absorption, distribution, metabolism, excretion (ADME) characteristics have been calculated with the assist of online server preADMET. [ABSTRACT FROM AUTHOR]

A novel series of lanthanide coordination polymers (Ln-CPs) have been obtained based on mixed ligands, 2-[(4-carboxyphenyl)methoxy]benzoic acid (H2cob) and 1,10-phenanthroline (phen), namely {Ln[(Hcob)(cob)(phen)]n, Ln = La (1), Pr (2), Sm (3), Eu (4)}. Complexes 1-4 were characterized by single crystal X-ray diffraction, elemental analysis, powder X-ray diffraction, infrared spectroscopy and thermogravimetric analysis. Single crystal X-ray diffraction revealed that complexes 1-4 show two-dimensional layer structures. The luminescence properties of complexes 3 and 4 were thoroughly investigated. [ABSTRACT FROM AUTHOR]

The influence of a defined impurity on the network characteristics of vitrimers made from an epoxidized eugenol derivative and various dicarboxylic acids is reported. One major characteristic of the monomer is the fact that it is not "clean" but rather is a mixture of the mono and diepoxidized eugenol derivatives. Mixtures like this could be thought to be representative of many technical grade compounds and the current system therefore serves as a model system to evaluate the effect of epoxide mixtures on the synthesis and the properties of the final vitrimers. The vitrimer preparation is found to be not affected by the different epoxy fractions, but in terms of the properties, there is an effect on the glass transition temperature both with the type of dicarboxylic acid but also with the level of epoxy functionalities present in the system. In spite of this, the ability of the vitrimer to perform the exchange reaction is not affected and all vitrimers can be reshaped or reprocessed showing that the processing is not affected by the changes in epoxy purity. [ABSTRACT FROM AUTHOR]

Polyaryletherketones (PAEK) are high-performance plastics with excellent mechanical properties and high thermal resistance used, e.g. as material for implants. Their molecular structure gives them a high level of chemical inertness but prevents bonding and adhesive interactions with other materials and integration into body tissue. Using the example of poly(ether ether ketone) (PEEK), we show novel synthetic routes for wet-chemical modification of the surface to create reactive carboxylic and amino groups. In a first approach, the ketone functionalities of the PEEK molecules were reduced to hydroxy groups and subsequently esterified with carboxylic acids. Using dicarboxylic acids, one acid group was bonded covalently to the PEEK surface while the other provided free acidic functionalities. In a second approach, the PEEK surface was modified in one step by reaction of the ketone group with a diamine, creating primary amino groups on the PEEK surface. All reaction products were analyzed by a powerful combination of surface sensitive X-ray photoelectron spectroscopy (XPS) and advanced infrared spectroscopic methods. [ABSTRACT FROM AUTHOR]

The phytoconstituents of the plant are directly or indirectly linked to the medicinal and advantageous qualities of the genus and are essential to the plant's self-defense against a variety of biotic and abiotic challenges. Plant genera have been divided into subcategories depending on the presence of these compounds, such as medicinal, anti-inflammatory, anti-stomachic, anti-cancer, and anti-diarrhoeal. The Convolvulaceae family, which includes the genus Distimake formerly known as Merremia, is known for having high alkaloid content. The present investigation is centered on the identification and assessment of bioactive compounds from two distinct species in this genus--Merremia aegyptia and Merremia dissecta--using GC-MS analysis. Distimake aegyptius (L.) A.R. Simoes and Staples and Distimake dissectus (Jacq.) A.R. Simoes and Staples are the new names for these species. The highest peak area percentage was reported for 1,2,4 butane triol (26.84%)in D. aegyptius stem sample, 1,2-benzene dicarboxylic acid, dibutyl ester (48.17%) from D. aegyptius seed sample, 1,3,4,5-tetrahydroxy cyclohexane carboxylic acid (Quinic Acid) (20.35%) in D. dissectus stem sample and (3ß)-Ergost-5-en-3-ol (Campesterol) (18.19%), stigmasta-5,22-dien-3-ol (19.23%), and gamma sitosterol (24.56%) in the D. dissectus seed sample making it a good source of phytosterols. These phytosterols possess antioxidant, anti-cancerous, anti-inflammatory, anti-hypercholesterolemic, and antidiabetic properties. GC-MS results revealed that some common phytochemicals were found in both the Merremia species. [ABSTRACT FROM AUTHOR]

This work highlights the importance of renewable materials, specifically polymers derived from epoxidized oils, in promoting sustainable development and reducing the environmental impact of various industries. The use of carboxylic acids as hardeners for biobased resins from epoxidized oils is also discussed as a promising development in this field. However, there is a lack of research in this area, and finding the right combination of carboxylic acids and epoxidized oils remains a challenge. The present work aimed to address this gap by synthesizing biobased resins using epoxidized soybean oil (ESO) and dicarboxylic acids with specific aliphatic chain lengths, such as oxalic, succinic, adipic and sebacic acids with 0, 2, 4 and 8 carbons in aliphatic chain. The curing and properties of the resulting biopolymers were investigated using DSC, FTIR, TGA, and swelling ratio assessments. FTIR spectra evidenced that the reaction between epoxy and carboxylic groups occurred by the presence of ester groups, as verified after the disappearance of the epoxy bands at ~ 829 cm−1 and the appearance of related bands to hydroxyl (-OH) at ~ 3500 and ester at 1685–1742 cm−1, respectively. DSC scans presented exothermic peaks related to the curing reactions associated to an increasing enthalpy (ΔH) as the aliphatic chain size increases. The activation energy, Eac, estimated using Friedman and Vyazovkin approaches, is highly influenced by the chain size and pKa of the acids. Furthermore, the thermal and hydrocatalytic degradation increase with the decrease of aliphatic chain. The study also introduces oxalic acid as a biobased cross linker for ESO, which has not been so far combined without any synthetic modifications in its structure. [ABSTRACT FROM AUTHOR]

Obesity has reached pandemic proportion not only in the West but also in other countries around the world; it is now one of the leading causes of death worldwide. A Western diet is rich in saturated fats and provides more calories than necessary, contributing to the rise of the obesity rate. It also promotes the development of liver steatosis, insulin resistance, hyperglycemia, and hyperlipidemia. In this issue of the JCI, Goetzman and colleagues describe the effects of consuming dicarboxylic acids (DAs) as an alternative source of dietary fat. The 12-carbon dicarboxylic acid (DC12) was administered to mice at 20% of their daily caloric intake for nine weeks in place of triglycerides. Notably, the change in diet increased the metabolic rate, reduced body fat, reduced liver fat, and improved glucose tolerance. These findings highlight DAs as useful energy nutrients for combatting obesity and treating various metabolic disorders. [ABSTRACT FROM AUTHOR]

The conditions for recording electrospray ionization mass spectra of dicarboxylic acids are selected to ensure the generation of doubly-charged negative ions of compounds containing more than 14 carbon atoms in the chain. The fragmentation of such ions under the conditions of collision-induced activation is described. It is shown that the main decomposition route is associated with the break of C–C bonds in the hydrocarbon skeleton of molecules. Thus, in contrast to the fragmentation of singly charged negative ions, the forced decomposition of bis-deprotonation products of decarboxylic acids makes it possible to obtain information about the structure of the molecular skeleton. [ABSTRACT FROM AUTHOR]

The decarbonization of chemical manufacturing is a multifaceted challenge that requires technologies able to selectively convert CO2-sequestering feedstocks using renewable energy. The electrochemical conversion of biomass is well-positioned to address this need. However, the electroactivity of biobased molecules that carry multiple redox centers remains challenging to predict and control. For instance, cis,cis-muconic acid, a conjugated dicarboxylic acid, is electrohydrogenated to trans-3-hexenedioic acid (t3HDA) with excellent yield and stereoselectivity while free energy calculations predict mixtures of 2- and 3-hexenedioic acids. To decipher this discrepancy, we studied the electrohydrogenation of C4 and C6 unsaturated acids, diacids, and their esters, and tied the observed product distributions to the electronic structure of the parent molecules. We show that the electrohydrogenation of the three isomers of muconic acid proceeds through a hydrogenating proton-coupled electron transfer (PCET) in the α position of the carboxylic acids and invariably yields t3HDA as the sole product. The selectivity can be explained by the electron-withdrawing effect of the carboxylic acid groups and the resulting perturbation of the local electron density that promotes the 2,5-hydrogenation over the thermodynamically-preferred 2,3-hydrogenation. This electronic perturbation is reflected in the computed Fukui indices, which can serve as local reactivity descriptors to predict product distributions not captured by calculated reaction thermochemistry. In addition to predicting the electroactivity of other unsaturated acids, this approach can provide insights into homogeneous electrochemical processes that may coexist with surface-mediated electrocatalytic transformations. [ABSTRACT FROM AUTHOR]

Using three different synthetic methods, 48 monoalkyl esters of 6 aliphatic dicarboxylic acids and 8 aliphatic alcohols were synthesized. Despite the method of synthesis, monoalkyl alkanedioates occurred in reaction mixtures along with corresponding dialkyl esters. This was caused both by a reaction mechanism and by possible secondary bimolecular disproportionation in solutions. However, for example, unlike monoalkyl phthalates, monoalkyl esters of aliphatic dicarboxylic acids appeared to be stable during their gas chromatographic separation. In no cases, characteristic chromatographic profiles indicating the decomposition of analytes in the chromatographic column were observed. The simultaneous presence of mono- and dialkyl esters in the samples allowed us to use the correlation of retention indices of mono- and dialkyl esters for their identification because the latter were characterized in more detail, namely, with RI(monoester) = aRI(diester) + b and some similar relations. The chromatographic peaks of monoalkyl alkanedioates (like for all carboxylic acids) on columns with nonpolar stationary phases were highly asymmetric. Their electron ionization mass spectra naturally indicated the presence of no signals of molecular ions. Mass spectra of monomethyl and monoethyl esters differed markedly from those of corresponding dialkyl esters, but they were similar for alcohols with R ≥ C3H7. [ABSTRACT FROM AUTHOR]

To study the effects of curing agent ratio, asphalt content, and crosslinking degree on the properties and distribution of epoxy asphalt with a compound system of dicarboxylic acid and acid anhydride, epoxy asphalt molecular models with two asphalt contents of 25% and 65% and three curing agent ratios of 10:1, 5:1 and 1:1 were constructed by Materials Studio. Various epoxy resin crosslinking degrees were further realised by Perl language crosslinking script. Glass transition temperatures were calculated to characterise low temperature flexibility. Energy systems and interaction energy were simulated to characterise the compatibility of epoxy asphalt. The radial distribution function (RDF) was calculated to observe the composition distribution of epoxy asphalt. The results show that the raise of the crosslinking degree and the proportion of anhydride curing agent increased the Tg of epoxy asphalt, impairing the low temperature performance. The increase in asphalt content was beneficial to the stability of the epoxy asphalt. Resin-based epoxy asphalt had stronger interaction between epoxy resin phase and asphalt phase, and the interaction energies both reached the maximum values at crosslinking degree of around 25%. Resin-based and asphalt-based epoxy asphalt had the most notable composition difference in the distribution of asphaltenes and acid anhydrides. [ABSTRACT FROM AUTHOR]

It is shown that the yield of micronization products in a supercritical antisolvent (SAS) precipitation can be used for a qualitative assessment of the solubility of substances in CO2–solvent mixtures. Assumptions for this approach are considered and recommendations are made to increase the accuracy of the assessment using this approach. The effect of the degree of supersaturation of the CO2–solvent–substance being micronized system on the morphology and size of particles of malonic and succinic acids micronized by the SAS method is studied. The possibility of obtaining α-succinic acid by the SAS method is demonstrated. [ABSTRACT FROM AUTHOR]

An automated on-line preconcentration and detection method for determination of dicarboxylic acids (DCAs) in aqueous samples is proposed. Parameters of two different off-line preconcentration methods (solid phase extraction – SPE, and concentrator columns) were tested and optimised. Compared with SPE columns, the concentrator column AC15 was chosen as the best choice for the next optimization followed by separation and detection by ion chromatography (IC). The sensitive method for determination of 7 DCAs (oxalic, malonic, succinic, maleic, glutaric, pimelic and azelaic acid) was devised with detection limits of 0.12–0.40 nM. The presented system describes an alternative on-line method usable for automated monitoring of selected analytes. [ABSTRACT FROM AUTHOR]

The coordination environment and networks of metal–organic frameworks (MOFs) play a significant role in their functional properties, especially catalysis. In recent years, the use of MOFs for electrocatalytic water-splitting reactions to produce green hydrogen fuel has gained increasing attention. Herein, we report the preparation of Co-benzene dicarboxylic acid-based MOFs (Co-MOF-1 and Co-MOF-2) with different coordination environments and correlated their structure-controlled electrocatalytic OER activity in an alkaline medium. Both Co-MOF-1 and Co-MOF-2 showed 3D network structures with different coordination environments around the Co metal centre. In Co-MOF-1, the Co metal centre is coordinated with DMF and pyridine along with a benzene dicarboxylic acid (BDC) ligand, whereas the Co metal centre is coordinated only with BDC ligands in Co-MOF-2. The Co metal centres in Co-MOF-1 contain labile solvent coordination but have completely saturated coordination with the BDC ligand alone in Co-MOF-2. Interestingly, Co-MOF-1 showed relatively strong OER activity and required the overpotential (η) of 294 mV to produce 10 mA cm−2 current density. However, Co-MOF-2 required the overpotential of 343 mV to achieve the 10 mA cm−2 current density. Further Co-MOF-1 showed comparatively low Tafel slope and charge transfer resistance and high electrochemical surface area than Co-MOF-2 and supported the enhanced OER activity. XPS analysis of Co-MOF-1 before and after catalysis suggested the conversion of Co-MOF-1 to CoOOH during the electrocatalysis that boosted the OER activity. The presence of a labile coordination site in Co-MOF-1 might have facilitated the interaction of hydroxyl electrolyte with the metal centre and active site generation by forming CoOOH easily which enhanced the OER activity. Co-MOF-1 also showed excellent stability for over 48 h. Hence, the present work provides structural insight for designing new MOFs for electrocatalytic water-splitting reactions. [ABSTRACT FROM AUTHOR]

Polyols made entirely from biomass could play a substantial role in producing greener polyurethanes (PUs) with lower environmental impact. Here, six fully biobased branched polyester polyols derived from hemicellulosic sugars and dicarboxylic acids were prepared by melt polycondensation and further utilized for the synthesis of twelve highly transparent and malleable PU thermosets. The latter were prepared by solvent-free step growth polymerization under extremely mild reaction conditions, easily applicable industrially. This included a very short reaction time (125–335 s), low operating temperatures (40–65 °C) and excellent yields (100%). In addition, no purification step was required. All the obtained PUs possessed very good thermal stability exceeding 235 °C, Tg (3.6–70.4 °C), and a broad hot-pressing window up to 192 °C above the respective Tg. These amorphous materials demonstrated a wide range of stress–strain behaviors, from hard to ductile, with elongation at break and tensile strength appearing in the 15–188% and 3.3–31.1 MPa range, respectively, comparable or superior to those of common commercially available fossil-based PU thermosets on the market. The enzymatic hydrolysis behaviour of the synthesized PUs was assessed using lipases from Candida rugosa and Aspergillus niger. All PUs showed some susceptibility to enzymatic attack, with a maximum mass loss up to 35% after 30 days. Most importantly, it was found that compositional control by tailoring of the length of the diacid unit in the branched polyol backbone and/or the chemical crosslinking degree of the resulting PU networks can be used as a practical method for effective 'on demand' tuning of the thermal properties, mechanical performance and enzymatic degradation rate. Taking advantage of these promising features in combination with the optical transparency, the developed polyurethane thermosets with easily adjustable properties show great potential as innovative materials for a wide application range. [ABSTRACT FROM AUTHOR]

The work presents an approach for studying the kinetics, mechanism, and reactivity of intermediates of a wide class of redox reactions for which the rate-limiting step is the redox decomposition of the intermediate complex. The approach was applied to the investigation of the oxidation of oxalic acid (H2Ox) by cerium(IV) in a sulfuric acid medium as part of the Belousov–Zhabotinsky oscillating reaction (BZ reaction) catalyzed by cerium ions. Experimental, mathematical, and computational methods that are typically used to study metal complexes in a stable oxidation state were kinetically generalized to variable-valence metal complexes and were used to determine the characteristics of intermediate complexes of the cerium(IV)–oxalate reaction and derive a general equation for its rate based on a set of equations describing the rapid achievement of pre-equilibrium in the system and the subsequent nonequilibrium process. A quantitative model of the process was proposed; it included two parallel reaction pathways, for which two different cerium(IV)–oxalate intermediate complexes were identified and characterized. The complexes have similar reactivity, which may be due to the similarity of the structure of their inner coordination spheres and the inner-sphere mechanism of electron transfer in the complexes. Using the developed model, a diagram of the yields of all main species of cerium(IV) under the conditions of the BZ reaction was constructed, which indicates the need to take into account the formation of intermediate complexes of the composition CeOHOx (n = 1, 2) in the oxidation of oxalic acid under these conditions. The main difference between the presented model of the cerium(IV)–oxalate reaction as part of the BZ reaction and the previous models is the explicit consideration of the participation of intermediate complexes of cerium(IV) with oxalic acid anions and sulfate background anions in the reaction. [ABSTRACT FROM AUTHOR]

New possibilities of the photochemical addition to fullerene С60 were demonstrated. Monosubstituted 1,9-dihydrofullerenes were obtained by irradiation of С60 in the presence of homologues of thiophene, pyridine, and naphthalene as well as esters of glutaric, phthalic, succinic, adipic, pyridinedicarboxylic acids and N-alkyllactam. The HC60 moiety is bound to the hydrocarbon part of the organic fragment. The product of the methyl glutarate addition was reduced by bis(arene)chromium to give a new ion-radical salt. [ABSTRACT FROM AUTHOR]

Azelaic acid (AZA) is a naturally occurring saturated dicarboxylic acid whose topical application has found multiple uses in dermatology. Its anti-inflammatory, antioxidant and antimicrobial properties against Propionibacterium acne are currently used in the treatment of various types of acne such as rosacea and acne vulgaris. AZA is an inhibitor of tyrosinase, mitochondrial respiratory chain enzymes and DNA synthesis, and is a scavenger of harmful free radicals and inhibits the production of reactive oxygen species by neutrophils. Interestingly, AZA also has anti-proliferative and cytotoxic effects on various cancer cells. To date, its inhibitory effect on melanocytes has been mainly used, making it widely used in the treatment of hyperpigmentation disorders such as melasma and post-inflammatory hyperpigmentation. Commercially available topical formulations with cosmetic and drug status contain 5% to 20% AZA in the form of gels and creams. The use of liposomal technology allows greater control over the pharmacokinetics and pharmacodynamics of the formulations. When applied topically, AZA is well tolerated, and side effects are limited to generally mild and transient local skin irritation. Importantly, liposomal technology has enabled the drug to penetrate all layers of the skin while maintaining a very high accumulation of the active ingredient. This solution could be revolutionary for the treatment of skin cancer, where until now the main obstacle was poor absorption through the skin, making the treatment require multiple applications to maintain long-term activity levels. In this review, we will present the mechanism of action and pharmacokinetics of AZA. We will summarize its use in the treatment of dermatoses and its potential in skin cancer therapy. We will provide an overview of the preparations available on the market, taking into consideration technologies used. [ABSTRACT FROM AUTHOR]

People have become conscious about recycling or reusing many things they use in the 21st century because diminishing vital resources make it necessary, both personally and socially. The evaluation of waste is also critical in terms of national economies. In this study, starch dicarboxylic compounds were synthesized using waste potato peels (WPP) in the presence of sodium hypophosphite monohydrate as a catalyst for the formation of the ester cross-links. Adipic acid, succinic acid, and glutaric acid were employed with waste potato starch (WPS) to obtain cross-linked samples: WPS-A, WPS-S, and WPS-G, respectively. The obtained compounds were characterized by attenuated total reflectance Fourier transform infrared (FTIR-ATR), scanning electron microscopy with energy-dispersive X-ray analysis (SEM-EDX), X-ray diffraction (XRD), and their cytotoxicity properties were investigated. The biocompatibility of the obtained WPS-dicarboxylic acid compounds against NIH-3T3 and L929 murine fibroblast cells with MTT assay was determined. Studies have shown that these compounds do not harm healthy cells and are found to be bioavailable. [ABSTRACT FROM AUTHOR]

This article provides a comprehensive overview of the relationship between cholesterol and atherosclerosis, focusing on the evidence that supports their causal link. It discusses the history of research on cholesterol and atherosclerosis, including the Framingham Heart Study and subsequent clinical trials that established the effectiveness of statins in reducing LDL cholesterol and cardiovascular events. The article also explores the development of nonstatin therapies, such as ezetimibe and PCSK9 inhibitors, as well as the introduction of bempedoic acid as an additional LDL-lowering agent. It emphasizes the importance of collaboration between industry and academic researchers in addressing cholesterol-related issues. The article concludes by discussing the need to address residual cardiovascular risk beyond LDL cholesterol, including the role of triglyceride-rich lipoproteins and inflammation. It highlights the potential benefits of bempedoic acid in targeting inflammation and its potential to mitigate fatty liver disease. The authors stress the importance of equitable access to new therapies and the necessity of rigorous clinical trials to establish their efficacy. They also emphasize the lessons learned from the conquest of cholesterol, including the role of basic research, collaboration, and the implementation of therapies. [Extracted from the article]

Two Al-MOFs, i.e., MIL-53 (Al) and (NH2)-MIL-53 (Al) have been synthesized using aluminium nitrate as metal ligands and 1,4 benzene dicarboxylic acid, amino 1,4 benzene dicarboxylic acid as organic linkers in aqueous medium at room temperature, respectively. Both Al-MOFs have been confirmed through different microscopy and spectroscopy tools. Afterwards, the optical properties of Al-MOFs have been confirmed in polar and non-polar solvents using photoluminescence spectroscopy. Finally, both Al-MOFs have been explored for optical nitrobenzene (NB) sensing. Interestingly, we have found excellent optical ability of NH2-MIL-53 (Al) over MIL-53 (Al) due to structural π–π* transitions. The photo-induced electron transfer mechanism has been found during the MOF–analyte interaction. Importantly, we confirmed that NH2-MIL-53 (Al) is an excellent sensing material for NB with a 0.28 ppb limit of detection over MIL-53 (Al). [ABSTRACT FROM AUTHOR]

Wilt caused by Fusarium oxysporum f. sp. ciceris (Padwick) is an important soil-borne disease and considered as most serious and widespread disease of chickpea throughout the world. Twenty indigenous isolates of Trichoderma spp. were isolated from the rhizosphere of chickpea in different geographic regions of Karnataka. Among twenty isolates, a higher concentration of volatile compounds was produced by TR-14 (72.22%) followed by TR-19 (66.67%) and TR-9 (65.93%). Further, the efficient strain that is TR-14 was identified as Trichoderma asperellum molecularly and was used to extract metabolites by using solvent extraction technique and subjected to GC-MS/MS analysis. The results have shown presence of twenty-nine compounds at different retention times ranging from 4.910 to 21.868 min. and the mass-tocharge (m/z) ratio from 43 to 190. Out of twenty-nine compounds, the concentration of 2-Imidazol-1-ylmethyl-pyridine 1-oxide (C9H9N3O) was highest with the maximum area (14375440) and retention time (19.842). Apart from this compound, 7-Isopropylidene-5-methyl-2, 3-diazabicyclo (2.2.1) hept-5-ene-2,3 dicarboxylic acid, diethyl ester was present at the highest peak with a retention time of 20.021. [ABSTRACT FROM AUTHOR]

Petroleum-based polyesters are widely used in daily life. However, their reliance on petroleum resources and non-biodegradability have raised concerns. Due to the advantages of being renewable, degradable, and abundant, bio-based polyester is expected to become a breakthrough in replacing petroleum-based polyester. In this study, p-hydroxybenzaldehyde, a bio-based monomer, was used to synthesize a novel diol, 2,2′-(4-((4-ethylphenyl)diazenyl)phenylazanediyl)diethanol (EDPD). The EDPD was then polymerized with 1,4-cyclohexanedimethanol (CHDM) and aliphatic diacids to synthesize a series of aliphatic-aromatic polyesters. Thermal analysis showed that the Tg varied from 43°C to 104°C, while the melting point (Tm) varied from 118°C to 156°C. All the polyesters exhibited high yield strengths (48–79 MPa) and tough values (elongation at break of 240–330%). After 30 weeks of soil incubation, the mass loss of the copolyester could reach 4.3%. The investigation of the eco-toxicity of the copolyesters showed that the survival rate of Eisenia foetida was more than 80%, demonstrating their low toxicity in natural habitats. The copolyesters investigated in this study exhibited good thermal, mechanical, and biodegradability properties. The properties of the copolyesters can be adjusted by varying the length of the carbon chains of the dicarboxylic acid moieties. These bio-based copolyesters could provide an important way to promote carbon neutrality and sustainable development of bio-based plastics. [ABSTRACT FROM AUTHOR]

New possibilities of the photochemical addition to fullerene С60 were demonstrated. Monosubstituted 1,9-dihydrofullerenes were obtained by irradiation of С60 in the presence of homologues of thiophene, pyridine, and naphthalene as well as esters of glutaric, phthalic, succinic, adipic, pyridinedicarboxylic acids and N-alkyllactam. The HC60 moiety is bound to the hydrocarbon part of the organic fragment. The product of the methyl glutarate addition was reduced by bis(arene)chromium to give a new ion-radical salt. [ABSTRACT FROM AUTHOR]

The controlled synthesis of metal organic nanosheets (MONs) still remains a challenge for scientists and is of primary interest in many research areas. In this study, we have developed a simple and reproducible one-pot synthesis method leading to tunable cobalt-based hybrid materials consisting of nanosheets with a well-defined morphology. The synthesis is performed via a solvothermal process assisted by primary amines acting as surfactants. The obtained materials are composed of ultrathin nanosheets with a rectangular morphology (width of about 50 nm and length greater than 100 nm). The different analysis techniques used show that the nanosheets are constituted by the alternation, in their width, of inorganic fringes (cobalt hydroxide) and organic ones (dicarboxylic acid) and that amine molecules stabilize their surface. 3D organisation of the nanosheets can be achieved at a synthesis temperature above 190 °C due to the interaction of alkyl chains of the stabilising amines. A multiparametric study based on SAXS experiments and TEM and PXRD analyses has highlighted the control of structural parameters by variations of some synthesis conditions. The inter-fringe distances are tunable from 1.0 nm to 1.5 nm through the length of the dicarboxylic linker and the distances between nanosheets can be modulated by the length of the alkyl chain of the primary amines. This efficient one-pot process seems to be very promising for the synthesis of tunable multiscale nanostructured MONs and can be implemented in many research areas, opening the way for various applications. [ABSTRACT FROM AUTHOR]

Dicarboxylic acid (diacid) homologs are essential indicators of secondary organic aerosols (SOA) that exert a considerable influence on climate changes and atmospheric chemistry. However, their sources and formation processes are poorly understood, leading to uncertainty in predicting the climate effect of SOA. A substantial drop in anthropogenic emissions during the COVID-19 lockdown (LCD) provides a "controlled experiment" to explore the effects of LCD measures and meteorological conditions on SOA. Here we investigated the difference in molecular distributions and stable carbon isotopic compositions (δ13 C) of diacid homologs in PM 2.5 before and during the LCD. We found that the concentration and contribution of diacid homologs during the LCD were higher than before the LCD, indicating that the enhanced secondary oxidation could offset the reduction in anthropogenic emissions during the LCD. A higher oxalic acid (C 2) / diacid ratio and more positive δ13 C values of major diacids during the LCD suggested more aged organic aerosols. The enhanced C 2 and related species during the LCD were mainly derived from the promoted gaseous photochemical oxidation by the higher oxidants and stronger solar radiation. However, C 2 and related species before the LCD were dominantly derived from the aqueous oxidation of α -dicarbonyls depending on relative humidity and liquid water content. The increased δ13 C values of C 2 and other major diacids along with the high ratios of C 2 / glyoxal, C 2 / methylglyoxal, and C 2 / diacid confirmed an isotopic fractionation effect during the oxidation process of precursors. Our results indicate that atmospheric pollution treatment depends on a balanced strategy and a coordinated effort to control multiple pollutants. [ABSTRACT FROM AUTHOR]

Aim: This systematic review and meta-analysis was conducted to synthesize the efficacy and safety of bempedoic acid in patients requiring lipid-lowering therapy. Methods: PubMed, Embase, and Scopus databases were searched for randomized controlled trials from inception till June 2023. The primary outcome was major adverse cardiovascular events (MACE), and secondary outcomes were all-cause mortality, serum lipid profile, and adverse events between bempedoic acid and comparators. ROB2 was used for risk of bias assessment. We pooled mean differences or relative risks (RR) along with 95% confidence intervals (random-effects model). Results: Five-hundred and thirty-one studies were screened and 17 (n = 21,131) were included for review. There was a significant reduction in the risk of MACE [RR, 0.88 (95% CI: 0.77 to 0.99), p = 0.03)] and all-cause mortality [RR, 0.90 (95% CI: 0.82 to 0.98), p = 0.02] following bempedoic acid treatment. Treatment with bempedoic acid led to a significant reduction in the mean serum total cholesterol [− 34.41 mg/dl (95% CI: − 42.43 to − 26.39), p < 0.001], low-density lipoprotein cholesterol (LDL-C) [− 33.91 mg/dl (95% CI: − 39.66 to − 28.17), p < 0.001], as well as high-density lipoprotein cholesterol (HDL-C) [− 2.40 mg/dl (95% CI: − 3.09 to − 1.71), p < 0.001] levels. However, there was a significant increase in the risk of hyperuricemia [RR, 2.05 (95% CI: 1.81 to 2.33), p < 0.001] following bempedoic acid treatment. The number needed to harm was large for all safety outcomes. The GRADE of evidence was moderate for all outcomes. Conclusion: Bempedoic acid reduces the risk of MACE and all-cause mortality, lowers serum total cholesterol and LDL-C levels, and has a favorable safety profile. Trial registration ClinicalTrial.gov Identifier: CRD42023412837. [ABSTRACT FROM AUTHOR]

A series of pseudorotaxanes with supramolecular organometallic silver(I) and gold(I) pillarplexes acting as rings and different α,ω‐dicarboxylic acids as axle components are reported. The successful formation of the host‐guest complexes is shown by 1H NMR spectroscopy and respective NMR titration. Additional evaluation with ITC titration experiments yielded dissociation constants (Kd) ranging from 10−5 to 10−7 M. Single‐crystal X‐Ray diffraction analysis reveals a particularly exciting pore alignment of different examples in the solid state depending on the length of the guest. The work highlights, that dicarboxylic acids can penetrate the tight tubular pillarplex pore, paving the way to future mechanically interlocked molecules and materials. [ABSTRACT FROM AUTHOR]

Polyurethanes (PU) are unique heteropolymers with a wide range of physicomechanical properties, fields of use and high development potential. PU is obtained by condensation of diisocyanate and various polyol compounds. The peculiarities of the structure and synthesis of commercial polyols based on the products of secondary oil processing, namely oligomeric glycols, oxides and dicarboxylic acids are presented. [ABSTRACT FROM AUTHOR]

Aim: Bempedoic acid has shown noteworthy progress in the prevention and management of atherosclerotic cardiovascular disease (ASCVD) in recent years. However, there has been a lack of high-quality evidence regarding the risk reduction of clinical events with bempedoic acid. Therefore, the aim of this article is to conduct a comprehensive evaluation of the impact of bempedoic acid on the incidence of cardiovascular events. Methods: A systematic review and meta-analysis of randomized controlled trials pertaining to bempedoic acid was carried out. We conducted a systematic search across the Pubmed, Embase, and Cochrane Central Register of Controlled Trials databases to identify relevant studies published from inception to 23 April 2023. A total of four trials comparing the clinical benefit achieved with bempedoic acid versus placebo were included. Results: Our analysis comprised four trials that encompassed a total of 17,323 patients. In comparison to the placebo, bempedoic acid showed a significant reduction in the risk of major adverse cardiovascular events (MACE) [relative risk (RR), 0.86, 95% confidence interval (CI) 0.87–0.94]. Additionally, bempedoic acid substantially lowered the occurrence of fatal or nonfatal myocardial infarction (RR 0.76, 95% CI 0.66–0.89), hospitalization for unstable angina (RR 0.70, 95% CI 0.55–0.89), and coronary revascularization (RR 0.82, 95% CI 0.73–0.92). There was also a similar reduction in MACE in patients on the maximally tolerated statin therapy. Conclusion: Bempedoic acid may reduce the risk of cardiovascular events regardless of whether the patient is taking stains or not. Registration: PROSPERO registration number CRD42023422932. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) have been increasingly applied in oxygen evolution reaction (OER), and the surface of MOFs usually undergoes structural transformation to form metal oxyhydroxides to serve as catalytically active sites. However, the controllable regulation of the reconstruction process of MOFs remains as a great challenge. Here we report a defect engineering strategy to facilitate the structural transformation of MOFs to metal oxyhydroxides during OER with enhanced activity. Defective MOFs (denoted as NiFc′xFc1‐x) with abundant unsaturated metal sites are constructed by mixing ligands of 1,1′‐ferrocene dicarboxylic acid (Fc′) and defective ferrocene carboxylic acid (Fc). NiFc′xFc1‐x series are more prone to be transformed to metal oxyhydroxides compared with the non‐defective MOFs (NiFc′). Moreover, the as‐formed metal oxyhydroxides derived from defective MOFs contain more oxygen vacancies. NiFc′Fc grown on nickel foam exhibits excellent OER catalytic activity with an overpotential of 213 mV at the current density of 100 mA cm−2, superior to that of undefective NiFc′. Experimental results and theoretical calculations suggest that the abundant oxygen vacancies in the derived metal oxyhydroxides facilitate the adsorption of oxygen‐containing intermediates on active centers, thus significantly improving the OER activity. [ABSTRACT FROM AUTHOR]

Monomers sourced from waste or biomass are often mixtures of different chain lengths; e.g. catalytic oxidation of polyethylene waste yields mixtures of dicarboxylic acids (DCAs). Yet, polyesters synthesized from such monomer mixtures have rarely been studied. We report polyesters based on multiple linear aliphatic DCAs, present in chain length distributions that vary in their centers and ranges. We demonstrate that these materials can adopt high‐density polyethylene‐like solid state structures, and are ductile (e.g. Et 610 MPa), allowing for injection molding, or film and fiber extrusion. Melting and crystallization points of the polyesters show no odd‐even effects as dipoles cannot favorably align in the crystal, similar to traditional odd carbon numbered, long‐chain DCA polyesters. Biodegradation studies of 13C‐labelled polyesters in soil reveal rapid mineralization, and depolymerization by methanolysis indicates suitability for closed‐loop recycling. [ABSTRACT FROM AUTHOR]

The electrocatalytic selective oxidation of 5‐hydroxymethylfurfural (HMF) presents a highly efficient and eco‐friendly method for biomass utilization. Herein, we synthesized pure β‐Ni(OH)2 and amorphous Ni(OH)2 on nickel foam (NF) using a facile stepwise electrodeposition technique and evaluated their catalytic performances for the oxidation of HMF to 2,5‐furan dicarboxylic acid (FDCA). The β‐Ni(OH)2 nanosheets‐decorated electrode (β‐NiNS/NF) exhibited excellent interfacial lattice matching with the substrate nickel, resulting in enhanced electron transfer at the catalyst‐substrate interface, as confirmed by electrochemical analysis. Consequently, the β‐NiNS/NF electrode displayed improved intrinsic electrocatalytic activity and interfacial stability. Additionally, it demonstrated effective HMF adsorption capability. These advantageous properties led to enhanced HMF conversion, selectivity, and structural stability. Notably, the β‐NiNS/NF electrode achieved an unprecedented FDCA yield of 80.6 % under relatively large current density galvanostatic electrolysis commonly used in industry. Moreover, our investigation identified a novel possible oxidation pathway during HMF electrocatalysis. This study not only showcases an efficient and scalable synthetic approach but also highlights the potential of the β‐NiNS/NF electrode for industrial HMF electrocatalytic oxidation under conditions involving relatively large applied currents. [ABSTRACT FROM AUTHOR]

Acyl-CoA-thioesterases, which hydrolyze acyl-CoA-esters and thereby release the respective acid, have essential functions in cellular metabolism and have also been used to produce valuable compounds in biotechnological processes. Thioesterase YciA originating from Haemophilus influenzae has been previously used to produce specific dicarboxylic acids from CoA-bound intermediates of the ethylmalonyl CoA pathway (EMCP) in Methylorubrum extorquens. In order to identify variants of the YciA enzyme with the capability to hydrolyze so far inaccessible CoA-esters of the EMCP or with improved productivity, we engineered the substrate-binding region of the enzyme. Screening a small semi-rational mutant library directly in M.extorquens yielded the F35L variant which showed a drastic product level increase for mesaconic acid (6.4-fold) and 2-methylsuccinic acid (4.4-fold) compared to the unaltered YciA enzyme. Unexpectedly, in vitro enzyme assays using respective M.extorquens cell extracts or recombinantly produced thioesterases could not deliver congruent data, as the F35L variant showed strongly reduced activity in these experiments. However, applied in an Escherichia coli production strain, the protein variant again outperformed the wild-type enzyme by allowing threefold increased 3-hydroxybutyric acid product titers. Saturation mutagenesis of the codon for position 35 led to the identification of another highly efficient YciA variant and enabled structure-function interpretations. Our work describes an important module for dicarboxylic acid production with M. extorquens and can guide future thioesterase improvement approaches. Key points: • Substitutions at position F35 of YciAHI changed the productivity of YciA-based release of carboxylic acid products in M. extorquens AM1 and E. coli. • YciAHI F35N and F35L are improved variants for dicarboxylic production of 2-methylsuccinic acid and mesaconic acid with M. extorquens AM1. • In vitro enzyme assays did not reveal superior properties of the optimized protein variants. [ABSTRACT FROM AUTHOR]

Fatty acids and bulk geochemical proxies were employed to understand the sources and transformation of sedimentary organic matter from surface sediments of major five mangrove systems in the northern Kerala coast. Texture, tidal rhythm and the proximity to the south eastern Arabian Sea were the main factors influencing distribution and accumulation of the organic matter in these systems. A total of 118 fatty acids were quantified and grouped into short-chain (SCFA), long-chain (LCFA), monounsaturated (MUFA), polyunsaturated (PUFA) and branched-chain (BrFA) fatty acids, hydroxy fatty acids, cyclic fatty acids, and dicarboxylic acids. The distribution of fatty acid groups was in the order SCFA > BrFA > MUFA > LCFA > PUFA. Total fatty acids (TFA) concentration exhibited profound seasonal variations and ranged from 6.25 to 580.49 lg/g (pre-monsoon > post-monsoon > monsoon except in Kadalundi which follows the reverse order). The sedimentary fatty acids in the study region reveal a wide spectrum of inputs from terrestrial, planktonic (preponderance of diatom followed by dinoflagellates along with brown algae, cyanobacteria, red algae) and bacterial sources (e.g., Desulfobulbus-type bacteria, sulfur-reducing bacteria, Sulfur-oxidizing bacteria). Significant concentrations of bacterial fatty acids suggest the functioning of an effective microbial loop and various biogeochemical pathways operating in these sediments (sulfate reduction, iron and manganese oxide reduction, etc.). [ABSTRACT FROM AUTHOR]

A series of polybenzimidazoles (PBIs) incorporated main chain 4-pyridine bridge groups were synthesized from 4,4′-([4,4′-bipyridine]-2,6,-diyl)bis (benzene-1,2-diamine) which reacted with four different diacids like isophthalic acid,4,4′-Oxibis benzoic acid, 5-amino isophthalic acid and 2,5-pyridine dicarboxylic acid using polyphosphoric acid as solvent. A process termed dispersion polymerizationhas been developed to prepare PBIs.For the membranepreparation, 4-pyridine-bridge polybenzimidazole (Py-PBI) productswere re-dissolved in dimethyl sulfoxide and cast. The polymer structure characterization included FT-IR, UV, Powder XRD, Water Uptake, Swelling Ratio, Ion exchange capacity, Acid doping, Acid leaching, Oxidative stability, and Polymer inherent viscosity find out by using Ubbelohde viscometer whilethermal stability assessments via thermogravimetric analysis. The Py-PBI-based polymer electrolyte membranes' mechanical properties measurement showed that the 4-pyridine-bridge PBIs membranes were flexible, thermally stable, and mechanically strong when compared with conventional PBI. The current-voltage (I-V) characteristics of the 4-Py-PBI membrane show that the conductivity of the 4441P membrane is 0.546 S cm−1. Graphical Abstract [ABSTRACT FROM AUTHOR]

The stereoselective synthesis of (5Z,9Z)-tetradeca-5,9-diene-1,14-dioic acid was carried out using Ti-catalyzed homo-cyclomagnesiation of 2-(hepta-5,6-dien-1-yloxy)tetrahydro-2H-pyran. Intermolecular esterification of this dicarboxylic acid with polyether acetylenic alcohols in the presence of carbodiimides was used to synthesize the corresponding monoesters and symmetric diesters. Using the intramolecular oxidative coupling of terminal triple bonds of the latter compounds, polyether macrodiolides containing 1Z,5Z-diene and 1,3-diyne fragments were synthesized. [ABSTRACT FROM AUTHOR]

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The aim of the study was the synthesis and application of novel adsorbents for the extraction of nucleotides from dietary supplements. Three different adsorbents modified with a silane containing two amine groups and various dicarboxylic acids were synthesized and characterized using various instrumental techniques. Next, different solvents were tested for their adsorption and desorption of five nucleotides. The results showed that the efficiency of both processes depends on the conditions used and the type of dicarboxylic acid bound to the surface of the adsorbent. The best results were obtained for succinic acid. The most effective adsorption occurred for water acidified with acetic acid to pH 4.5, while the highest recoveries (85–102%) with high reproducibility were obtained for 10 mM ammonium acetate at pH 9. The nucleotide extraction was performed simply by changing the charge at the adsorbent surface, providing the possibility of electrostatic attraction and repulsion between the adsorbent and nucleotides. Moreover, the sorption capacity of the obtained materials was also determined, which was essential for their use in extracting nucleotides from real samples by dispersive extrusion to the solid phase. The new adsorbents and the developed extraction method were successfully applied to isolate nucleotides from two different dietary supplements with different compositions (one of them with yeast strains). The method is simple and reproducible; no organic solvents or high-concentration inorganic salts are used (it is environmentally friendly). The entire process is performed in one centrifuge tube and is cheaper compared with methods used so far. [ABSTRACT FROM AUTHOR]

In an effort to probe the biophysical mechanisms of inhibition for ten previously-reported inhibitors of metallo-β-lactamases (MBL) with MBL IMP-1, equilibrium dialysis, metal analyses coupled with atomic absorption spectroscopy (AAS), native state mass spectrometry (native MS), and ultraviolet-visible spectrophotometry (UV-VIS) were used. 6-(1H-tetrazol-5-yl) picolinic acid (1T5PA), ANT431, D/l-captopril, thiorphan, and tiopronin were shown to form IMP-1/Zn(II)/inhibitor ternary complexes, while dipicolinic acid (DPA) and 4-(3-aminophenyl)pyridine-2,6-dicarboxylic acid (3AP-DPA) stripped some metal from the active site of IMP but also formed ternary complexes. DPA and 3AP-DPA stripped less metal from IMP-1 than from VIM-2 but stripped more metal from IMP-1 than from NDM-1. In contrast to a previous report, pterostilbene does not appear to bind to IMP-1 under our conditions. These results, along with previous studies, demonstrate similar mechanisms of inhibition toward different MBLs for different MBL inhibitors.

To understand the characteristics of chemical components and dicarboxylic acids, oxocarboxylic acids and α‐dicarbonyls in atmospheric aerosols at underground coal fire environment, we collected fine aerosols (PM2.5) from Wuhai, Inner Mongolia, North China, where the underground coal fire often occurs. PM2.5 samples were analyzed for the measurements of carbonaceous components, stable carbon isotopic composition (δ13C) of total carbon, and molecular distribution and compound‐specific δ13C of diacids, oxoacids and α‐dicarbonyls. Oxalic acid (C2) was the most abundant species, accounting for 43.2%–63.1% (avg. 50.8%) of total diacids, followed by phthalic acid (Ph) (13.7%). Azelaic acid (C9) was the third most (7.4%) abundant, followed by succinic (C4) and malonic (C3) acids. Significant correlations of C2 diacid with glyoxylic (ωC2) and 3‐oxopropanoic (ωC3) acids and C3 diacid and their δ13C implied that diacids and related compounds were mainly derived from the underground coal fire emissions and subsequent in situ secondary formation. Based on molecular distribution, seasonal pattern and linear relations of C9 diacid with C2, C3, ωC2 and ωC3 as well as with Ph acid and total diacids, together with the comparability and similarity of its δ13C (−27.0 ± 0.9‰) with that of Ph acid and organic matter in coals, respectively, we found that the C9 diacid has been mainly derived from its precursors such as unsaturated fatty acids emitted from underground coal fires and their subsequent in situ photochemical oxidation. However, further research is needed to confirm such an importance of coal combustion for azelaic acid loading in atmospheric aerosols. Plain Language Summary: Fine aerosols in the atmosphere cause high uncertainty in radiative forcing of the Earth's climate system and have become one of the serious environmental risk factors, causing more than 6 million premature deaths annually. The atmospheric environment over the underground coal fire field is different from that in urban area, because the emission of inorganic gaseous species, volatile organic compounds and particulates that consist oxygen‐containing organic species and polycyclic aromatic hydrocarbons and their subsequent photochemical oxidation processes are relatively larger at the coal fire field. Our study on fine aerosols from underground coal fire field at Wuhai, North China showed a rather large abundance of dicarboxylic acids associated with a specific partitioning from the coal fires compared to observations from other environments including an unusual abundance of azelaic acid. Key Points: The characteristics of diacids in atmospheric aerosols at underground coal fire environment have been investigatedAzelaic acid could be applied in evaluating the coal combustion influence on secondary organic aerosols in the atmosphereC2 was mainly derived from underground coal fire emissions and their subsequent in situ photochemical oxidation [ABSTRACT FROM AUTHOR]

The electrocarboxylation of α,α-dichloroarylmethane derivatives in the presence of CO2 was achieved, providing several α-chloroarylacetic acid derivatives with modest yields but high selectivity (chlorinated vs. non-chlorinated or dicarboxylic acid products). The obtained products were then involved in several chemical transformations, underlining their potential as versatile intermediates in synthetic chemistry. A mechanism was also proposed based upon a control experiment and cyclic voltammetry (CV) study. [ABSTRACT FROM AUTHOR]

Auricularia heimuer is a widely cultivated jelly mushroom. The fruiting bodies are categorized into cluster and chrysanthemum types. With changing consumer demands and the need to reduce bio-waste, the demand for clustered fruiting bodies is increasing. Therefore, gene mining for fruiting body types is a matter of urgency. We determined that the A. heimuer locus for fruiting body type was located at one end of the genetic linkage map. The locus was localized between the markers D23860 and D389 by increasing the density of the genetic linkage map. BlastN alignment showed that the marker SCL-18 was also located between D23860 and D389, and a total of 25 coding genes were annotated within this interval. Through parental transcriptome analysis and qRT-PCR verification, the locus g7219 was identified as the gene controlling the fruiting body type. A single-nucleotide substitution in the TATA box of g7219 was detected between the parents. By PCR amplification of the promoter region of g7219, the TATA-box sequences of the cluster- and chrysanthemum-type strains were found to be CATAAAA and TATAAAA, respectively. This study provides a foundation for the breeding of fruiting body types and strain improvement of A. heimuer. [ABSTRACT FROM AUTHOR]

Pairs of α-carbanions generated from lithium 2-methylpropanoate, butanoate, pentanoate, hexanoate, heptanoate, and phenylacetate by the action of lithium diisopropylamide on the corresponding acids (AH, BH) in THF reacted with 1,2-dibromoethane to give mixtures of oxidative homo- (2,2,3,3-tetramethyl-, 2,3-diethyl-, 2,3-dipropyl-, 2,3-dibutyl-, 2,3-dipentyl-, and 2,3-diphenylbutanedioic acids) and heterocoupling products (3-ethyl-2,2-dimethyl-, 2-ethyl-3-propyl-, 2-butyl-3-ethyl-, 2-ethyl-3-pentyl-, 2-ethyl-3-phenyl-, 2-butyl-3-propyl-, 2-pentyl-3-propyl-, 2-phenyl-2-propyl-, 2-butyl-3-pentyl-, 2-butyl-3-phenyl-, and 2-pentyl-3-phenyl-butanedioic acids) in overall yields of 83–99%. The ratio of the homo- and heterocoupling products depended on the structure of the initial α-carbanions. [ABSTRACT FROM AUTHOR]

Pretreatment is a necessary step to converting lignocellulosic biomass from its native form into a more accessible form for the value-added utilization of its main components. Herein, we developed a one-step acid bleachable pretreatment method using a recyclable acid hydrotrope (p-toluenesulfonic acid, p-TsOH) and chlorate to achieve the fibers bleaching and lignin extraction simultaneously. Under a pretreatment condition of a p-TsOH concentration of 80 wt.%, a pretreatment temperature of 80 °C, and a pretreatment time of 45 min, 84.33% of hemicelluloses and 76.79% of lignin were dissolved out from poplar wood. The obtained dispersed solids with a whiteness of 60.13% can be used for papermaking or ethanol production. The results from quasi-simultaneous enzymatic saccharification and combined fermentation (Q-SSF) of the pretreated substrate indicated that the ethanol concentration and yield reached to 39.30 ± 0.57 g/L and 82.36 ± 1.15%, respectively. According to the results of lignin characterization, the aromatic rings in extracted lignin were opened forming dicarboxylic acids as well as derivatives due to the oxidation effect of chlorate, which is beneficial for its catalytic upgrading and composites preparation. Therefore, this study is important to valorization of lignocellulosic biomass. [ABSTRACT FROM AUTHOR]

Due to the lack of studies on chestnut metabolites, this study was conducted to identify and quantify the major phenolic constituents in chestnuts. Data were compared with the three most commonly grown interspecific hybrids of C. sativa and C. crenata ('Bouche de Betizac', 'Marsol', and 'Maraval') and three "native" accessions of C. sativa. High-performance liquid chromatography coupled with mass spectrometry was used to identify and quantify these compounds. Four dicarboxylic acid derivatives, five hydroxybenzoic acids, nine hydroxycinnamic acids, and three flavanols were identified and quantified, most of them for the first time. Hydroxybenzoic acids were the major phenolic compounds in all chestnut cultivars/accessions, followed by flavanols, dicarboxylic acid derivatives, and hydroxycinnamic acids. Of all the compounds studied, the (epi)catechin dimer was the most abundant in chestnut. The assumption that cultivars from commercial hybrids have a better and different metabolic profile than "native" accessions was refuted. [ABSTRACT FROM AUTHOR]