European Journal of Chemistry
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Solubility enhancement and structural insights into pipemidic acid via salt formation with benzoic acid
Full text linkPipemidic acid (PMA) is an active pharmaceutical ingredient (API) belonging to the quinolone class of antibacterial agents, primarily used to treat urinary tract infections. This study investigated improving the dissolution properties of poorly soluble PMA by forming a 1:1 stoichiometry molecular salt (4BA) with benzoic acid (BA). Liquid-assisted grinding and slow evaporation techniques were used to prepare the solid form of the salt. The salt was then characterized using differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), and single-crystal X-ray diffraction (SC-XRD). The DSC analysis provided information on the changes in thermal behavior associated with the formation of the salt. FTIR spectroscopy helped identify the functional groups present and potential interactions between PMA and benzoic acid. SC-XRD determined the definitive three-dimensional arrangement of atoms within the salt structure, revealing a wave-like hydrogen bonding network directing a 3D layered packing of molecules. This improved packing is believed to be responsible for the improved solubility of PMA in the salt form. The Hirshfeld surface analysis, along with its associated 2D fingerprint plots, further elucidated the intermolecular interactions within the crystal lattice. This analysis showed that, in addition to the strong N-H···O and O-H···O hydrogen bonds, weaker H···H, C···H, and H···C interactions also play a significant role in stabilizing the molecular packing. Finally, cumulative drug release (CDR) showed that the formation of the molecular salt significantly improved the dissolution behavior of PMA, potentially leading to sustained drug release
Exploring the miRNA-148b and the caspase-3/Bcl-2/Bax axis as a potential predictive marker in breast cancer
Full text linkBreast cancers (BCs) are the second leading cause of cancer-related deaths among women due to a lack of prediction, diagnosis, and follow-up. MicroRNAs (miRNAs) in liquid biopsies (LBs) are promising tools for the prediction and follow-up of cancer. This study aims to investigate and compare serum miRNA-148b, caspase-3, Bax, Bcl-2, and total antioxidant capacity (TAC) of BC patients with healthy controls. In this study, 300 women were included and divided into four groups of 75 each: Group 1 consisted of healthy controls, Group 2 of early-stage BC patients, Group 3 of chemotherapy-treated BC patients, and Group 4 of mastectomy-treated BC patients. Blood samples were collected for a complete blood count and serum samples were tested for miRNA-148b Bax, caspase-3, Bcl-2, and TAC. RT/PCR, ELISA and spectrophotometric methods were used to determine these parameters. In addition, histopathological examinations were performed on breast tissue samples. The present results indicated that BC patients exhibited elevated miRNA-148b, Bax, and Bcl-2 expressions compared to healthy controls. Importantly, advanced BC stages showed significantly higher miRNA-148b levels than early stages. However, levels of caspase-3 and TAC were reduced in BC patients compared to healthy controls. Histopathological analysis revealed various alterations in breast tissues, including nuclear changes, the presence of giant cells, and inflammation. The present study concluded that miRNA-148b and Bcl-2 are markedly elevated in the serum of BC patients compared to healthy subjects; however, Bax and caspase-3 levels were reduced. These findings underscore that blood miRNA-148b and caspase-3 are promising avenues for the prediction and follow-up of BC patients
Levels of selected metals in spices cultivated in Southwest Ethiopia: Occurrence and health risk assessment
Full text linkIn this study, the levels of seven metals (Ca, Cd, Cr, Cu, Zn, Pb, and Ni) in the soil and spice plants grown around Oromia Region of Southwest Ethiopia were analyzed using flame atomic absorption spectrometry (FAAS) after acid digestion. The pH of the soil samples was found to be in the range of 5.86 to 6.57, with organic matter 13.93 to 20.59% and electrical conductivity 0.28 to 0.49 mS/m. Among the metals determined, Ca was the most prevalent, ranging from 429.01 to 5369.67 mg/kg, Zn 31.88 to 67.70 mg/kg and Cu 7.62 to 10.67 mg/kg in plants, while Cd, Cr, Pb, and Ni were not detected in the spice plants. Ca was the most abundant metal in soils, ranged from 1195.67 to 4147.17 mg/kg, followed by Zn, Cr, Ni, and Cu, ranging from 112.90 to 120.25 mg/kg, 21.92 to 45.76 mg/kg, 21.40 to 56.93 mg/kg and 13.03 to 28.67 mg/kg, respectively. Cd and Pb were not detected in the soil samples. The hazard quotient and hazard index values of Cu and Zn in all spices were below one, which may ensure that these spices do not pose substantial health risks to consumers
Response surface methodology optimization and modeling of green synthesis conditions for TiO2-ZnO nanocomposites using Vigna unguiculata L. extract
Full text linkDeveloping a more efficient and sustainable method than conventional chemical and physical approaches to synthesize TiO2-ZnO nanocomposites is essential to reduce environmental impact. Green synthesis offers a sustainable alternative, minimizing toxic solvents and utilizing renewable biological sources. TiO2-ZnO NCs is a well-known binary nanocomposite with different potential biomedical, photocatalysis and solar cell applications due to its excellent physiochemical properties. This study presents the response surface methodology, optimization, and modeling of the reaction conditions of TiO2-ZnO NCs by green synthesis using the co-precipitation method from Vigna unguiculata L. extract as a reducing and stabilizing agent. Optimization of independent reaction conditions such as amount of dopant, reaction temperature, initial pH, and stirring time was performed using Response Surface Methodology-Box Behnken Design (RSM-BBD) of the design expert version 13 software (DX13). The strength and amount of active site of the synthesized TiO2-ZnO NCs were calculated by back titration analysis. The results show that TiO2-ZnO NCs were successfully precipitated and the optimization study obtained shows that the optimum number of active sites (8.881 mmol/g) of the TiO2-ZnO NCs was achieved at 10.00% MR of TiO2, 90 °C reaction temperature, initial pH of 11 and 23 min stirring time. The optimal reaction conditions were supported and confirmed by the solution ramp functions and bar graph plots. Statistically, the regression model and analysis of variance (ANOVA) revealed that the initial pH was the most significant parameter among the selected reaction conditions with the probability value (p-values) of 0.0011. The two-dimensional (2D) contour and three-dimensional (3D) response surface plots demonstrated a good interaction between the reaction variables during the biosynthesis. The porosity, particle size distribution (PSD) and specific surface area (SSA) of optimized TiO2-ZnO NCs were evaluated using the nonlinear density functional theory (NLDFT) method. Consequently, the pore volume, pore size and SSA for the developed TiO2-ZnO NCs were found to be 5.45×10-2 cm3/g, 3.23 nm, and 351.80 m2/g, respectively, indicating that the optimized TiO2-ZnO NCs are mesoporous in nature. This work indicated that mesoporous TiO2-ZnO NCs were prepared through the novel use of Vigna unguiculata L. extract. RSM-BBD was successfully used in the design of experiment, model development, and optimization of highly active TiO2-ZnO NCs production
Macromolecular crowder polyethylene glycol delayed the aggregation of chromium-treated bovine serum albumin
Full text linkThe structure of proteins is greatly affected by various interacting xenobiotic and lead to the formation of aggregates. Chromium metal, which was initially considered innocent as a nutrient, has been found to induce some abnormalities in the human body recently. Aggregate formation is associated with the occurrence of pathological conditions such as systemic amyloidosis, cystic fibrosis, etc. To have a deeper insight into aggregation susceptibility and structural stability of bovine serum albumin on treating with hexavalent chromium Cr(VI) and the consequences of macromolecular crowding on the native conformation of the protein, the chromium concentration ranged from 0-100 µM where K2Cr2O7 was used as the Cr (VI) source. Disruption of native bovine serum albumin (BSA) assembly and formation of aggregates at 50 µM Cr(VI) was unveiled by increased turbidity and fluorescence at 350 nm, reduced intrinsic fluorescence with 10 nm and 20 nm blue shifted enhanced ANS spectra respectively. Significantly enhanced, the ThT fluorescence alone side sigmoidal curve with no lag phase and a 10 nm red shift in congo red spectra sustained conformational changes and indicated aggregation of BSA upon incubation with Cr(VI). Circular dichroism (CD) results showed the disappearance of negative minima at 208 and 222 nm, which confirms the transition of native helical structure to non-native beta sheets. Furthermore, the comet assay showed that Cr-treated BSA aggregates were found to be genotoxic, as an increase in tail length of 11.3 μm had been observed. Crowded microenvironment was mimicked by PEG-4000; a polyethylene glycol, was witnessed to prominently preserve conformational stability of BSA upon treatment with Cr(VI) as all results observed were close to that of native. The decrease in turbidity, fluorescence at 350 nm accompanied by a reduction in 8-anilinonaphthalene-1-sulfonic acid (ANS) and thioflavin T (ThT) fluorescence further verified the inhibition of aggregate formation in the presence of PEG-4000. Furthermore, the increased intrinsic fluorescence, decreased congo red absorption and reduced tail length of 3.4 μm in the comet assay were in co-relation with the above data. The macromolecular crowder PEG-4000 was efficient in delaying the aggregation of Cr-treated BSA, as the kinetics showed a sigmoidal curve with the lag phase. Based on these findings, it could be hypothesized that the native structure was maximally retained in the presence of 100 mg/mL of PEG-4000, demonstrating braking of aggregate formation. It can be established that explicit consideration of macromolecular crowding using a relevant range of inert crowding agents must be a prerequisite for studies concerning intracellular conformational behavior of proteins and enhanced their stability under stress conditions and devising protein formulations with enhanced conformational stability
Click chemistry in tuberculosis research: From drug design to therapeutic delivery - A systematic review
Full text linkThe molecular hybridization of 1,2,3-triazoles with various bioactive scaffolds has become a promising approach to the development of new antitubercular drugs, offering a versatile platform for improving drug efficacy and specificity. This review covers key advancements over the past decade in creating triazole-based hybrids that integrate azoles, coumarin/chromene, isoniazid, quinoline/dihydroquinoline, quinolone, ferrocene, isatin, furan, and other structures. These hybrid molecules generally show improved potency against both drug-sensitive and drug-resistant Mycobacterium tuberculosis strains while maintaining favorable toxicity profiles, making them particularly valuable in the current landscape of rising drug resistance. Structure-activity relationship (SAR) studies highlight that strategic substituent positioning and optimal linker selection are critical in enhancing antimycobacterial efficacy. Furthermore, modifications to the electronic and steric properties of the hybrids have been shown to influence their ability to bypass common resistance mechanisms, underscoring the potential of these compounds to overcome treatment barriers. In particular, several of these hybrids demonstrate promising activity against MDR-TB and XDR-TB strains, suggesting potential applications for immunocompromised patients, such as those with HIV co-infection. Collectively, these findings offer valuable insights for the rational design of next-generation antituberculosis agents that could transform tuberculosis (TB) treatment paradigms in both resistant and sensitive cases of TB
An efficient synthesis, anticancer and antimycobacterial activities of new substituted pyridine based azomethine derivatives
Full text linkPyridine, a fundamental heterocyclic scaffold, is a key structural component in numerous biologically active molecules, including alkaloids, vitamins B3 and B6, coenzymes, and other natural products. Its significance in medicinal chemistry arises from its versatile physicochemical properties, such as its capacity to form hydrogen bonds, its high water solubility, and its chemical stability. In this study, a series of substituted pyridine-based analogues (3a-h) were synthesized and their structural elucidation was performed using various spectroscopic techniques. These derivatives incorporate an azomethine functionality within the pyridine core. The structural characterization of the newly synthesized compounds was achieved through spectroscopic analyses, including mass spectrometry, 1H NMR, 13C NMR, infrared (IR) spectroscopy, and complementary analytical methods such as solubility and melting point determination. The biological evaluation of the derivatives 3a-h was carried out to assess their in vitro cytotoxic activity against the human colon cancer cell line HCT-15 and the breast cancer cell line MCF-7 using the sulforhodamine B (SRB) assay. The results indicated that the synthesized compounds exhibited an anticancer activity ranging from moderate to promising. Furthermore, the compounds were subjected to preliminary antituberculosis (anti-TB) screening against Mycobacterium bovis, a representative strain of Mycobacterium tuberculosis, at varying concentrations
Spectroscopic and DFT study of a glutamic acid Nd(III) complex
Full text linkDue to the large number of electrons occupying 4f orbitals, the computational chemistry of lanthanide complexes is not as easy as that of d-block ones. As a result, even though lanthanide molecules have attracted attention in various fields in recent years, there has been little research on their spectrochemical properties or computational science in detail. In this study, we experimentally measured electronic, circular dichroism (CD), fluorescence, and infrared (IR) spectra as well as the direct current (DC) magnetic susceptibility curves (magnetization (M) versus magnetic field (H) curves (MH) and magnetization (M) versus temperature (T) curves (MT)) of a mononuclear Nd(III) complex with a glutamic acid ligand and to test the density functional theory (DFT) calculation conditions that can be performed from the structure optimization. Bands of C=O and N-H were observed in the IR spectrum, and paramagnetism was confirmed by measurements. The fluorescence intensity of the DMSO solution at 300 K was very weak. Ultraviolet-visible (UV-vis) and CD spectra showed a strong intraligand transition at 200-250 nm and relatively strong sharp f-f transitions at 581, 742, and 801 nm (like the solvated Nd(III) ion). Thus, herein we synthesized lanthanide Nd(III) complexes coordinated with amino acids and conducted structure estimation research by comparing experimental measurement results such as electron microscopy, spectroscopy, and magnetism with DFT calculations (optimized structure). Lanthanide complexes are difficult to study because their coordination numbers are large, their solution structures are unclear, and their large number of electrons makes computational chemistry difficult. In general, metals have large ionic radii, and thus can potentially have high coordination numbers. Metal ions of hard Lewis acids prefer hard-base ligands (especially oxygen atoms in water and amino acids). Therefore, it is interesting to try to easily understand the structure in solution by comparing spectroscopic experiments with computational chemistry
