Adipic Acid Research Articles

Assessment of the cytotoxic effect of aerial parts of Gazania rigens hexane extract on HRT-18 and MCF-7 cell line and chemical composition analysis using GC/MS and LC/MS

Gazania rigens are cultivated for their vividly colored flowerheads. The herb, belonging to the Asteraceae family, displays various classes of secondary metabolites, including terpenes, phenols and fatty acid derivatives. Antioxidant, hepatoprotective, nephroprotective, and antimicrobial activities of the herb have been evaluated and have proven to benefit humans clinically specially in case of cancer affected people. Breast cancer is the second most frequent reason for female mortality, and the third most frequent reason in the world is colorectal cancer. A previous study stated the in vitro anticancer effect of the genus Gazania rigens on the MCF-7 breast cancer cell. N-hexane extract of Gazania rigens aerial parts was prepared by maceration, cold extraction methods and subjected to GC/MS and LC-MS analysis to characterize its constituents. In GC/MS, the total number of identified compounds were 2-pentadecanone, 6,10,14-trimethyl, hexadecanoic acid methyl ester, 11-octadecenoic acid methyl ester, methyl stearate hexanedioic acid, and bis(2-ethylhexyl) ester. LC/MS analysis revealed and confirmed the presence of lupeol. Based on the result, n-hexane extract was evaluated for its in vitro anticancer effect against the MCF-7 and HRT-18 cell lines using an MTT assay. Results from the MTT assay showed there is a significant cytotoxic effect for hexane extract against both cell line HRT-18 and MCF-7, the IC50 value for HRT-18 was 102.2±10 ug/ml, while the IC50 value for MCF-7 was 121.2±12 ug/ml.

Tetracarpidium conophorum nuts (African walnuts) up-regulated adiponectin and PPAR-γ expressions with reciprocal suppression of TNF-α gene in obesity.

Tetracarpidium conophorum nuts are nutrient-dense Nigerian snacks associated with weight regulation. This study explores the nuts' impact on adipose tissue gene expression associated with low-grade inflammation. Ethanol whole extract (EWE), ethyl-acetate fraction (EAF) and the resulting residue (RES) were orally administered once daily to MSG-induced obese rats for 6 weeks (n = 6). Afterward, the RNA synthesis of inflammation-associated genes was measured, and GC-MS ligands in the extract and fractions were docked against their protein products in silico. The study found that in obese animals, PPAR-γ and Adiponectin expressions were down-regulated, while TNF-α was up-regulated, indicating an increased low-grade inflammatory process in adipose tissue. After 6-week oral treatments with EWE, EAF and RES, PPAR-γ and Adiponectin expressions increased significantly, while TNF-α expression decreased, suggesting the modulation of obesity-induced inflammation in adipose tissue. The in silico molecular docking analysis identified four lead compounds likely responsible for the observed effect, namely 6-Isopropenyl-4,8a-dimethyl-4a,5,67,8,8a-hexahydro-1H-naphthalen-2-one, 9,12,15-Octadecatrienoic methyl ester (Z,Z,Z), 9,12,15-Octadecatrienoic acid and Hexanedioic acid, bis(2-ethylhexyl). Of these compounds, 6-Isopropenyl-4,8a-dimethyl-4a,5,67,8,8a-hexahydro-1H-naphthalen-2-one demonstrated the strongest affinity to the binding cavities of PPARγ (-7.3 kcal/mol), Leptin (-5.2 kcal/mol), Adiponectin (-7.1 kcal/mol) and TNF-α (-6.3 kcal/mol) and was better than the standard drug, Orlistat (-6.7, -4.4, -6.8 and - 4.5 kcal/mol, respectively). The study reveals that T. conophorum nuts possess bioactive compounds/drug candidates that can exert positive modulation, at the molecular level, the low-grade inflammatory process associated with obesity, which normally facilitates the outset of complications.

Cyanobacterial hydrothermal carbonization carbon as photocatalyst for selective aerobic oxidation of cyclohexane

The exploration of catalyst preparation techniques that incorporate environmental-friendly methodologies has consistently been the focus of scientific inquiry within the field of green synthesis of oxygen-containing organic chemicals. Herein, a metal-free hydrothermal carbonation carbon (HTCC) has been prepared utilizing cyanobacterial biomass produced during a water bloom in a freshwater lake. The HTCC produced is capable of performing photocatalytic selective oxidation of cyclohexane to cyclohexanol and cyclohexanone (KA oil) under ambient conditions. The use of cyanobacterial biomass allows for the efficient preparation of HTCC, which exhibits a conversion rate of cyclohexane that is 4.1 times of HTCC prepared with alternative carbon sources (glucose). The selectivity to KA oil over the samples are almost 100%. Characterizations and analysis reveal that cyanobacteria can lead to self-doping of nitrogen and hydrophobicity of the resulting HTCC, while sulfuric acid etching endow it with more photoactive sp2 hybridized structure units that contribute to a higher photogenerated carrier separation efficiency. The suitable band structure enables the cyanobacterial HTCC to produce superoxide radicals to oxidize cyclohexane. These findings are of great significance for the development of eco-friendly photocatalysts and the utilization of biomass resources.

Preparation of adipic acid from glycerol derivative by photodehalogenative C–C homocoupling: Synergistic effect of Ag cocatalyst and alkali

Preparation of adipic acid from glycerol derivative by photodehalogenative C–C homocoupling: Synergistic effect of Ag cocatalyst and alkali

Application of a novel hexagonal ultrasonic reactor for intensified crystallization of adipic acid

Application of a novel hexagonal ultrasonic reactor for intensified crystallization of adipic acid

Techno-economic and environmental assessment of a sugarcane biorefinery: direct and indirect production pathways of biobased adipic acid

Techno-economic and environmental assessment of a sugarcane biorefinery: direct and indirect production pathways of biobased adipic acid

A drug-loaded nano chitosan/hyaluronic acid hydrogel system as a cartilage tissue engineering scaffold for drug delivery

Cartilage lesions, especially osteoarthritis (OA), usually arise from aging, trauma, or obesity and require medical intervention due to the damaged site's inflammation and the cartilage tissue's poor self-healing capacity. This study aimed to prepare a drug-loaded nanoparticle hydrogel system with anti-inflammatory and chondroprotective effects to treat OA. First, hyaluronic acid (HA) was oxidized to create aldehyde functional groups and then cross-linked with adipic acid dihydrazide (ADH) to form a hydrogel. Next, chitosan nanoparticles (CS NPs) loaded with an anti-inflammatory molecule (fisetin) and or a chondrogenic and chondroprotective agent (kartogenin) were incorporated into the hyaluronan hydrogel to improve the release profile of the drug and increase its retention time in the joint cavity. Incorporating drug-loaded NPs into the hyaluronan hydrogel provided the hydrogel with controlled release features and improved properties. In addition, the real-time PCR (Polymerase chain reaction) results showed that the hyaluronan hydrogel containing both drug-loaded NPs performed better than either constituent alone on an in vitro model of OA. Finally, based on the results of in vitro evaluation, this drug-loaded nanoparticle hydrogel system can be a promising technique for treating OA by rapidly suppressing inflammation and supporting cartilage regeneration and requires further investigation in an animal model of OA. Meanwhile, this study investigated, for the first time, the effect of the simultaneous use of fisetin and kartogenin together with a nano CS/HA hydrogel system to treat OA.

Computation-driven redesign of an NRPS-like carboxylic acid reductase improves activity and selectivity.

Engineering nonribosomal peptide synthetases (NRPSs) has been a "holy grail" in synthetic biology due to their modular nature and limited understanding of catalytic mechanisms. Here, we reported a computational redesign of the "gate-keeper" adenylation domain of the model NRPS-like enzyme carboxylic acid reductases (CARs) by using approximate mechanism-based geometric criteria and the Rosetta energy score. Notably, MabCAR3 mutants ACA-1 and ACA-4 displayed a remarkable improvement in catalytic efficiency (kcat/KM) for 6-aminocaproic acid, up to 101-fold. Furthermore, G418K exhibited an 86-fold enhancement in substrate specificity for adipic acid compared to 6-aminocaproic acid. Our work provides not only promising biocatalysts for nylon monomer biosynthesis but also a strategy for efficient NRPSs engineering.

The Effect of the Structure of the Alcohol Component on the Plasticizing Ability of the Ester of Aliphatic Dicarboxylic Acid

Esters of aliphatic dicarboxylic acids are promising plasticizers of polyvinyl chloride due to their low toxicity and high biodegradability. Plasticized PVC materials containing them are characterized by high frost resistance and heat resistance. In this regard, esters of adipic acid and alkoxylated alcohols with various structures have been obtained. The influence of alcohol structure on the plasticizing ability of ether has been determined. A theoretical assessment of the plasticizing effect of diesters in relation to PVC was performed based on the calculation of Hansen solubility parameters. For this purpose, the thermodynamic compatibility of adipates with PVC was investigated. The processability of esters in the composition of PVC compositions was studied according to the values of the critical temperature of dissolution of PVC. The intervals of transition of plastics from a glassy to a highly elastic state, as well as the depression of the glass transition temperature of compounds containing adipates, were determined. Rheological characteristics of PVC compositions based on the obtained adipates were investigated. It is shown that the chemical structure of the alcohol group determines the important technological and operational characteristics of esters in the composition of polymer materials.

Processable solid-solid full-phase change composites with novel elevated enthalpy from synergistic crystallization facilitated on hydrogen bonding interactions

Given the growing energy demands, organic phase change materials (PCMs) have been widely explored, with leakage and high phase change enthalpy being primary concerns for practical storage applications. In this study, micro-crosslinked PCMs were prepared using polyethylene glycol (PEG), poly (butylene terephthalate) (PBT), trimesic acid (TA) and adipic acid (AA) through simple esterification and transesterification, firstly. To prevent the leakage of myristic acid (MA) during its solid-liquid phase change, micro-crosslinked PCMs were then used as encapsulation materials and melting-blended with MA to produce solid-solid full-phase change composites (FPCCs). The resulting FPCCs showed superior processability due to the micro-crosslinked structure of encapsulation materials and plasticization effect of MA with low molecular weight. All FPCCs exhibited a single phase change temperature despite the significant difference in phase change temperatures between the micro-crosslinked PCMs and MA. Notably, the actual enthalpy of all FPCCs was higher than their theoretical enthalpy, with FPCCs-3 showing a 12.5 % increase over its theoretical value. The onset and final decomposition temperatures of MA in FPCCs were enhanced by at least 34.6 % and 10.6 %, respectively, compared to those of pure MA. The hydrogen bonding interactions between the carboxyl groups of MA and oxygen atoms of PEG segments are responsible for these extraordinary properties.

Biobased and biodegradable polyester amides based on nylon 6,6 and polybutylene adipate via straightforward bulk polymerization

Aliphatic polyesters are generally known for their limited thermal and mechanical properties, but are prone to biodegradation. On the other hand, aliphatic polyamides, mainly represented by nylons, feature high thermal transition points and enhanced mechanical strength, but are usually classified as nonbiodegradable. In this work, the properties of the aliphatic polyester polybutylene adipate and nylon 6,6 were combined by synthesizing polyester amides. Relatively low- and high-molecular weight series, Mn¯ 7000 and 14400 g/mol, respectively, were synthesized via a straightforward bulk polymerization process by utilizing biobased starting materials: butanediol, adipic acid and nylon 6,6 salt. The amide-to-ester ratio was varied to analyze the influence of the amide content on the molecular structure, thermal properties, mechanical properties, hydrophilicity and biodegradability. Strong relationships between the amide content and the Tg, Tm, degree of crystallinity, and mechanical properties were observed. Water contact angle measurements revealed that all the polyester amides were hydrophilic. Finally, the biodegradation experiments demonstrated that all polyester amides are prone to biodegradation in activated sludge and that the amide content had a major influence on the biodegradation rate. This work supports the high potential of biobased polyester amides for applications in numerous fields due to their versatility in terms of polymeric properties and sustainable character.

DFT Analysis on Adipic Acid to Propel Creative Advancements in Supercapacitor Technology

The increasing dependence on non-renewable resources for energy storage has accelerated the development of supercapacitor technology, which is now essential to portable devices and electric cars because of its high-power density and quick charge/discharge speed. Optimized geometry, weak C-H‧‧‧O hydrogen bonding interactions inside methylene groups affect bond lengths, and the carboxylic group in adipic acid (ADPI) shortens bond lengths (C14–C15 and C4–C5). DFT simulations demonstrate a fair agreement to experimental data. According to vibrational studies, the O-H and C=O groups' vibrational frequencies are greatly influenced by the reactive hydrogen bonding displayed by the -COOH group in carboxylic acid derivatives. With theoretical values demonstrating significant PED contributions, these interactions reduce the O-H stretching frequency, which is seen as an O-H stretching band at 3405 cm⁻¹ in the FT-IR spectra. In ADPI, atoms interact with neighboring atoms' σ* orbitals (O2-C4), (O12-C14), (C4-C5), (C14-C15), (O1-C4), and (O11-C14) through lone pairs of electrons localized on O1 (LP2), O11 (LP2), O2 (LP1), and O12 (LP1); these interactions have fairly high stabilization values of 33.78, 33.78, 17.91, 17.91, 6.75, and 6.75 kcal/mol, accordingly. Redox peaks and increased specific capacitance with scan rate are revealed by cyclic voltammetry study of ADPI, suggesting efficient electron transport, improved charge storage, and encouraging prospects for electrochemical energy storage applications. ADPI's appropriateness for high-performance electrochemical applications such as supercapacitors is supported by its impedance analysis, which is displayed by a Nyquist plot with a decreased semicircle and a sharp low-frequency slope. This plot demonstrates effective electron transfer, ion diffusion, and capacitive behavior.

Toray and PTT explore biobased adipic acid

Toray and PTT explore biobased adipic acid

Injectable Polydopamine Nanoparticle-Incorporated Hydrogels for Antiangiogenesis and Stimulating Tumoricidal Immunity to Inhibit Metastasis and Recurrence Postresection.

Surgical resection is still the main means for clinical treatments of breast cancer, but the postoperative immunosuppressive microenvironment and neoangiogenesis of the residual tumors easily lead to tumor metastasis and recurrence, which will further endanger patients' lives. The combination of antiangiogenic therapy and immunotherapy may promote the mutually reinforced cycle of immune reprogramming and vascular normalization to avoid tumor metastasis and recurrence. Herein, we prepared polydopamine nanoparticles for improving tissue adhesion and enriching tumor-associated antigens. This nanoregulator together with regorafenib (REG) was further incorporated into a hydrogel developed from grafting adipic acid dihydrazide onto 2,2,6,6-tetramethylpiperidine-1-oxyl radical oxidized chitin and oxidized hyaluronic acid, which was injectable at the cavity after subcutaneous tumor surgery with good mechanical properties and degradability. The system showed long-term release of REG. After combining with anti-PD-L1, the hydrogel applied to the surgical wound exhibited a reduction in tumor metastasis and recurrence. This effect was achieved by suppressing angiogenesis and enhancing antitumor immunity, characterized by increased levels of effector T lymphocytes and activation of dendritic cells within tumors, spleens, and draining lymph nodes. The injectable hydrogel offers a promising strategy for postoperative management aimed at preventing tumor metastasis and recurrence.

Insights into the Synergistic Catalytic Effect of TiO2 Supported V-W Oxides for Selective C-H Bond Oxidation of Cyclohexane to KA Oil.

It is urgent to develop an efficient and stable non-noble metal catalyst for selective C-H bond oxidation of cyclohexane. Herein, a series of V-W oxides supported on TiO2 catalysts (V-W/TiO2) were fabricated. The V-W/TiO2 catalysts exhibited much higher catalytic activity for the selective oxidation of cyclohexane to KA oil, compared to that of V/TiO2 and W/TiO2 catalysts. The good distribution of active metals and the synergistic effect were responsible for the enhanced catalytic activity. H2-TPR results disclosed that the presence of V in V-W/TiO2 affected the reducibility of W6+ species, and XPS verified that an electronic interaction was formed between them. Such results led to good catalytic reusability of V-W/TiO2 catalyst during the reactions, and no obvious activity loss was found after six runs. The reaction mechanism was investigated, and the results verified that hydroxyl radicals generated from H2O2 homolysis were the main active oxidative species. Theoretical study revealed that V dopant could regulate electronic structure of adjacent O atom, facilitating the adsorption of cyclohexane, and lower energy was needed for the rate-limiting step over V-W/TiO2 during the whole oxidation reaction. This work developed an efficient V-W/TiO2 catalyst for the selective oxidation of cyclohexane via a synergistic effect.

Major-auxiliary cooperative metal pairs in MOFs enable cascade oxidation of KA oil to ε-caprolactone

Direct oxidation of KA oil (the mixture of cyclohexanone and cyclohexanol) toward ε-caprolactone is in high demand yet hard to implement in need of juggling the activation of both methyne C-H bond of cyclohexanol and α-C-C bond of cyclohexanone. Here we demonstrate that in situ formed Cu1+δ-Oδ-• active site, which originates from relay reaction at Ni(II) and Cu(I) pairs in a metal-organic framework (known as NiCu-MOF-74) with O2 and benzaldehyde (PhCHO), efficiently oxidizes KA oil toward ɛ-caprolactone along with good stability. Mechanism investigation discloses that the auxiliary Ni(II) site first adsorbs O2 for abstracting formyl hydrogen in PhCHO followed by transfer of PhCO· to react with another O2 over the major Cu(I) site, leading to formation of Cu1+δ-Oδ-• and PhCOOH. This major-auxiliary cooperative strategy will be particularly suitable for multivariate MOFs as next generation catalysts towards complex reactions.

One-step fabrication of Bi2MoO6 nanowires-g-C3N4 composites for outstanding photocatalytic performance in cyclohexane oxidation

Selective oxidation of cyclohexane into cyclohexanone (K) and cyclohexanol (A) stands as a pivotal process in industrial chemistry. However, the challenges associated with activating the C-H bond and the vulnerability of KA oil to over-oxidation detract from the economic significance of this reaction. This study focuses on the preparation of a bismuth molybdate ultrathin nanowires-carbon nitride (Bi2MoO6-g-C3N4) heterojunction through a one-step hydrothermal approach for significantly improving the photocatalytic oxidation of cyclohexane. Bi2MoO6 ultrafine nanowires with the diameter of 6 nm were adhered tightly on the surface of g-C3N4 nanosheets with the assistance of oleyl amine. The type II heterojunction of Bi2MoO6-g-C3N4 composite facilitated a more efficient separation of charges and boosted the photocatalytic performance in the cyclohexane oxidation. The Bi2MoO6-g-C3N4 composite demonstrated outstanding photocatalytic performance with a 10.66 % conversion rate of cyclohexane, surpassing the individual efficiencies of Bi2MoO6 and g-C3N4 by 1.9 and 2.2 times, respectively. Moreover, it demonstrated an outstanding KA oil selectivity of 99.32 %, showcasing exceptional levels of both conversion and selectivity simultaneously. Through the utilization of photoelectrochemical analysis, research on band structures, experiments on radical trapping and monitoring, we have extensively investigated the mechanism of photocatalysis. The type II charge transfer in Bi2MoO6-g-C3N4 heterojunction restricted the redox capacity of electrons in the conduction band and holes in the valence band, effectively curbing over-oxidation reactions of KA oil, thus achieving remarkable KA oil selectivity. It offers a valuable insight into the creation of heterojunctions to boost the efficiency of photocatalytic oxidation of cyclohexane, showing promise for advancing the field of photocatalysis.

Determining factor of enzyme conjugates, bridge heterology and analytical variables of immunogens in prednisolone ELISA

In this study, adipic acid dihydrazide (ADH), carbohydrazide (CH), ethylenediamine (EDA), and urea (U) were used as spacer molecules, covalently linking prednisolone (PSL) to carrier proteins for immunogen preparation, and PSL to enzymes for enzyme conjugate preparation using N-hydroxysuccinimide (NHS)-mediated carbodiimide reactions. The resulting immunogens were used to generate antiserum in New Zealand white rabbits. Antibodies produced against immunogens with various spacers were tested for immunoreactivity with enzyme conjugates, both with and without spacers, in a total of twenty different combinations. All combinations demonstrated binding and were subsequently evaluated through displacement studies. Sensitivity and specificity tests revealed that the combination of PSL-21-HS-U-BSA-antibody with PSL-21-HS-HRP enzyme conjugate exhibited the best sensitivity (0.032 ng/mL) and limited cross-reactivity with other steroids. This combination was further examined for analytical parameters, showing recovery rates of 93.87–101.19 % for PSL from spiked human serum samples, with intra- and inter-assay CVs of <8.88 %. The serum PSL values obtained by this method showed strong correlation with a commercially available ELISA kit (r2 = 0.97, n = 78).

Untargeted metabolomics profiling for revealing water-soluble bioactive components and biological activities in edible bird’s nest

Edible bird’s nest (EBN) is a functional food renowned for its numerous health benefits. While its nutritional and therapeutic value is well-documented, the metabolites contributing to the bioactivities of EBN remain poorly understood. This study aimed to identify the metabolites present in EBN subjected to different treatments, including double-boiled EBN (EBNdb), EBN hydrolysate (EBNhydro), EBN fermented with Lactobacillus helveticus (EBNLH), Latilactobacillus curvatus (EBNLC), and Latilactobacillus sakei (EBNLS) using liquid chromatography-mass spectrometry (LC-MS) and correlate the identified bioactive metabolites with the bioactivities of EBN. It was found that the fermented EBNs exhibited the highest number of metabolites, with 76 tentatively identified, followed by EBNhydro (45) and EBNdb (37). Citric acid (1.97–4.48 g/kg) was present in all treated EBN samples, while L(+)-lactic acid (3.03–8.07 g/kg) and adipic acid (2.33–3.18 g/kg) were only found in fermented EBNs. Among the treated EBN samples, EBNLC demonstrated the significantly highest (p ≤ 0.05) antioxidative (22.34 ± 0.41 % 1,1-diphenyl-2-picrylhydrazil radical scavenging activity), antihypertensive (5.46 ± 0.26 % angiotensin-converting enzyme inhibitory activity), and antihyperglycemic activities (6.48 ± 0.34 % α-amylase inhibitory activity). A total of 18 metabolites, including citric acid, 4-sphingenin, N-acetylcitrulline, 4-aminophenol, L(+)-lactic acid, 2-oxoadipate, sildenafil, formylglycinamidin-RP, 11β,17α,21-α-5β-pregnane-3,20-dione, 2-ketobutyric acid, homoserine, benzaldehyde, 1-pyrroline4-hydroxy-2-carboxylate, nortriptyline, 1-methylguanine, 3-hydroxy-trimethyllysine, 3-phenylpropionate, and reserphine were predicted as bioactive metabolites using the partial least squares discriminant analysis (PLS-DA). This study provides valuable insights into the metabolites present in EBN and serves as fundamental data for future investigations into the bioactive compounds responsible for its specific health benefits, potentially leading to the development of enhanced EBN-based functional foods.

Altering the Solid Electrolyte Interface Through Surface-Modification of Lithium Metal Anode for High-Voltage Lithium Battery

The physical structure and chemical composition of the solid electrolyte interphase (SEI) affect the performance of the lithium metal anode. The tuning of the chemical composition and structure of the SEI through the surface modification of the lithium metal anode has been conducted. A series of dicarboxylic acids, oxalic acid, malonic acid, succinic acid, glutaric acid, and adipic acid have been utilized to modify the surface of the lithium anode. Physical characterization methods have been employed to study the surface morphology and chemical composition of the SEI. Symmetrical (Li/Li) and asymmetrical (NMC622/Li) cells with pristine lithium and surface modified lithium electrodes have been assembled and tested. NMC622/Li cell with surface modified lithium shows improved performance compared to that of pristine lithium. Malonic acid-treated lithium outperforms all the electrodes by retaining 141 mAh g−1 specific capacity even after 100 cycles of charge-discharge. XPS depth profiling analysis reveals that the SEI on the MA-Li contains evenly distributed organic and inorganic components which are responsible for the performance of MA-Li.