Frontiers in Chemistry最新文献

Bisphenol A (BPA) poses a significant environmental threat due to its widespread use as an industrial chemical and its classification as an environmental endocrine disruptor. The urgent need for effective BPA removal has driven research toward innovative solutions. In this study, we present the synthesis and application of a novel 2D-3D spherically hierarchical Zn₅In₂S₈ (ZIS) photocatalyst for the photocatalytic degradation of BPA under visible light for the first time. Compared to the conventional g-C₃N₄ photocatalyst, ZIS exhibits enhanced optical and electrical properties, leading to remarkable photocatalytic performance, with an apparent reaction rate constant of 2.36 h⁻¹, 6.56 times greater than that of g-C₃N₄. This efficacy allows for the degradation of 99.9% of BPA in just 2 h. The photocatalytic mechanism of ZIS was elucidated through various material characterizations and photoelectrochemical assessments, demonstrating improved light absorption and efficient charge separation as key factors facilitating BPA degradation. Notably, ZIS maintains high photocatalytic activity and stability over multiple cycles, indicating its potential as a sustainable photocatalyst. These findings not only contribute to the development of efficient photocatalysts for environmental remediation but also underscore the significant role of Zn₅In₂S₈ in photocatalysis and solar energy conversion.

Background: Monkeypox (Mpox) is a re-emerging zoonotic disease with limited therapeutic options, necessitating the exploration of novel antiviral agents. Curcuma longa (turmeric) is a widely used medicinal plant known for its antioxidant and anti-inflammatory properties, primarily attributed to its bioactive curcuminoids.

Aim: This study aimed to evaluate the therapeutic potential of C. longa aqueous extract (CAE) against monkeypox through phytochemical characterization, biological assays, and computational analyses.

Methodology: Phytochemical analysis, including HPLC, identified key Curcumin, Bisdemethoxycurcumin, Demethoxycurcumin, Tetrahydrocurcumin, Curcuminol, and Ar-curcumene. The DPPH assay and total antioxidant capacity (TAC) were employed to assess antioxidant activity. Anti-inflammatory effects were determined by measuring the inhibition of heat-induced protein denaturation. Molecular docking and molecular dynamics (MD) simulations were performed to evaluate the interactions between curcuminoids and monkeypox virus proteins.

Results: The aqueous extract of C. longa was prepared via decoction, yielding 7.80% ± 0.81% extract with curcumin as the predominant compound (36.33%). The CAE exhibited strong antioxidant activity with a TAC of 36.55 ± 0.01 µg GAE/g d.w., an IC50 of 0.77 ± 0.04 mg/mL in the DPPH assay, andan EC50 of FRAP of 3.46 ± 0.11 mg/mL. Anti-inflammatory analysis showed 78.88 ± 0.53%inhibition for egg albumin and 90.51 ± 0.29%for BSA. Molecular docking identified demethoxycurcumin (DMC) as the most potent compound, with binding affinities of -8.42 kcal/mol (4QVO), -7.61 kcal/mol (8CEQ), and -7.88 kcal/mol (8QRV). MD simulations confirmed the stability of DMC complexes, with the 4QVO-DMC interaction being the most stable, showing RMSD fluctuations within a range of 0.2-0.6 nm, with an average fluctuation of 0.4 nm, and consistent compactness with Rg values remaining between 1.8 and 2.0 nm, with a fluctuation of only 0.2 nm over 100 ns.

Discussion: The results demonstrate the multifunctional therapeutic potential of C. longa, driven by its potent antioxidant and anti-inflammatory properties. The computational findings suggest that curcuminoids, particularly demethoxycurcumin, could serve as promising antiviral agents against monkeypox. These findings pave the way for further preclinical studies to validate the antiviral efficacy of C. longa bioactives and their potential applications in combating viral infections.

Trichoderma is an antagonistic fungus used commercially; however, the viability of these formulations is affected by biotic and abiotic factors. In this research, microcapsules of sodium alginate reinforced with nanocellulose and/or chitosan were developed to encapsulate T. longibrachiatum conidia and characterized by SEM, FTIR, and TGA. The viability of the microencapsulated conidia was evaluated through different temperatures (room temperature, 5°C and 37°C), as well as their in vitro antagonistic potential against Fusarium oxysporum. The formulations evaluated had encapsulation efficiencies above 92% and the microcapsules with alginate, chitosan, and nanocellulose maintained 100% viability at 37°C for 2 months. In addition, all formulations evaluated retained antagonistic ability against F. oxysporum. These findings support the use of alginate, nanocellulose and chitosan for the formulation of microcapsules to maintain the viability of T. longibrachiatum conidia over time and at different temperature conditions.

Microorganisms are becoming resistant to drugs and antimicrobials, making it a significantly critical global issue. Nosocomial infections are resulting in alarmingly increasing rates of morbidity and mortality. Plant derived compounds hold numerous antimicrobial properties, making them a very capable source to counteract resistant microbial strains. Syzygium aromaticum (Clove) extract has been proven by studies to contain active ingredients that demonstrate antibacterial, antifungal, antioxidant, and insecticidal properties. It has also been used historically for its pain relief especially for tooth ache. Clove extract derived nanoparticle synthesis is a promising method of combining therapeutics with metals at nanoscale. Such nanostructured systems in combination with the heterocyclic antibiotic clarithromycin could potentiate the action of plant extracts, decrease drug side effects and improve antimicrobial activity. In this study, clove extract (C) was successfully used to synthesize silver nanoparticles (AgNP) to create AgNPC and AgNPCA (A = clarithromycin). The two compounds underwent different analytical methods consisting of SEM, EDS, DLS, UV-vis, FTIR and XRD. These nanoparticles were used against a variety of 10 pathogens and exhibited very good to intermediate antibacterial properties. AgNPC resulted in better antibacterial properties and smaller nanoparticle size. This study demonstrates the potential of clove extract mediated AgNP synthesis in combination with and without the antibiotic clarithromycin.

An interesting approach of including an upconverter in the MoS₂ counter electrode can yield broadband light harvesting Pt-free DSSC assembly. Here different upconverter (UC) nanoparticles (Yb, Er incorporated NaYF₄, YF₃, CeO₂ & Y₂O₃) were synthesized and loaded in MoS₂ thin film by hydrothermal method. The inclusion of UCs in MoS₂ films exposed without any secondary formation of upconverters and the uniform deposition of the films are confirmed through XRD and FESEM analysis respectively. The absorption spectrum (UV-Vis-NIR) confirms the increase in absorption intensity in visible and NIR regions due to the incorporation of UCs. Under 980 nm excitation, the UCs-loaded MoS₂ films show emission in blue (450-490 nm), green (520-540 nm) and red (600-700 nm) regions due to the f-f inner transition occurring in the Er ions. The oxide and fluoride UCs-based DSSCs were fabricated with an FTO/TiO₂/N719/Triiodide electrolyte/UC@MoS₂/FTO assembly. Oxide UCs show greater electrocatalytic activity, which might be owed to the films exposed with more catalytic active sites favourable for ion transportation in the I^-/I^- ₃ electrolyte. Among them, higher photoconversion efficiency (PCE) of 7.1% was witnessed for (Y₂O₃: Er, Yb) @MoS₂ counter electrode-based DSSC which is due to the good conductivity (R_S) of the film, the longer electron lifetime and photon harvesting enhancement by upconversion process. It is notably convinced that the UC-loaded MoS₂ films can be used as an effective counter electrode for the possible realization of upconverter DSSC and used for broadband light absorption.

This study investigates the significance of single-walled (SWCNTs) and multi-walled (MWCNTs) carbon nanotubes with a convectional fluid (water) over a vertical cone under the influences of chemical reaction, magnetic field, thermal radiation and saturated porous media. The impact of heat sources is also examined. Based on the flow assumptions, the fundamental flow equations are modeled as partial differential equations (PDEs). Using the appropriate transformation, the PDEs are converted to ordinary differential equations and then solved via RK4 in MATLAB. To confirm the results, a comparison is made with a previously investigated problem, finding good agreement. The emerging dimensionless physical parameters impact on the flow problem is determined through graphs and tables. Analysis reveals a dual solution for the suction and injection parameter. Therefore, stability examination is implemented to confirm a stable solution. The aim of the study is to analyze SWCTs and MWCTs in a vertical cone with stability to establish that only the first solution is reliable. The analysis here signifies that large volume fractions can be substituted to increase the nanofluid movement. The mathematical model and graphical demonstration indicate that the velocity of MWCNTs is higher than SWCNTs. Moreover, the local skin friction, rate of heat transfer, and Nusselt and Sherwood numbers improve with Biot number.

Introduction: To design effective small molecule inhibitors targeting the immune checkpoint PD-1/PD-L1 and to explore their inhibitory activity.

Methods: In this paper, a total of 69 PD-1/PD-L1 inhibitors with the same backbone were searched through opendatabases, and their docking mechanism with PD-L1 protein was investigatedby molecular docking method, and the active conformation of the inhibitors was explored. The biological activity of the four newly designed inhibitors was also evaluated using ELISA.

Results: The most active molecule 58 in the dataset formed six hydrogen bonds with Phe67, Val55, Ile116 and Tyr123, while the second most active molecule 34 formed five hydrogen bonds with Phe67 and Ala121, both of which formed π-π stacking interactions with Tyr56. The analysis of the inhibitor docking results determined that the residues Tyr123, Gln66, Thr20, Met115, Asp122 and Ile116 had the greatest influence on the active conformation of the inhibitor. ELISA assays suggested that the four novel inhibitors designed had high inhibition rates, with the inhibition rate of compound N2 being as high as 68.53%.

Discussion: In this paper, we have designed and synthesized various PD-1/PDL1 inhibitors, which provide a basis for drug discovery targeting the PD-1/PDL1 signaling pathway.

Background: Selpercatinib, a selective RET kinase inhibitor, is approved for treating various cancers with RET gene mutations such as RET-rearranged thyroid cancer and non-small cell lung cancer. The presence of process-related and degradation impurities in its active pharmaceutical ingredient (API) can significantly affect its safety and effectiveness. However, research on detecting these impurities is limited.

Methods: This study developed and systematically validated a High-Performance Liquid Chromatography (HPLC) method for identifying selpercatinib and its related impurities. The method utilized a 4.6 mm × 250 mm chromatographic column with 5 μm particles, employing a flow rate of 1.0 mL/min, a detection wavelength of 235 nm, an injection volume of 10 μL, and a column temperature of 35°C. Mobile phase A was composed of a 9:1 ratio of water to acetonitrile, with the aqueous component adjusted to pH 2.5 and containing 2 mM potassium dihydrogen phosphate (KH₂PO₄) and 0.4% triethylamine. Mobile phase B was pure acetonitrile. The gradient elution program was as follows: 0-2 min, 5%B; 2-15 min, 5% to 15%B; 15-30 min, 15% to 35%B; 30-35 min, 35% to 45%B; 35-36 min, 45% to 5%B; 36-45 min, 5%B.

Results: The chromatographic method established in this study was validated according to the ICH Q2 (R1) guidelines. The developed HPLC method demonstrated excellent specificity, sensitivity, stability, linearity, precision, accuracy, and robustness. It efficiently separated the impurities present in selpercatinib, thereby confirming the method's efficacy in ensuring the purity and quality of the drug.

Conclusion: The chromatographic method established in this study can be used for the detection of selpercatinib and its impurities, providing significant reference value for the quality research of selpercatinib bulk drug and its preparations, and ensuring the safety of medication for patients.

Introduction: This work outlines the design, synthesis, and biological evaluation of a new series of benzimidazole/1,2,3-triazole hybrids as apoptotic antiproliferative agents that inhibit the EGFR pathway.

Methods: The research assesses the antiproliferative efficacy of compounds 6a-i and 10a-i against various cancer cell lines.

Results and discussion: The research emphasizing hybrids 6i and 10e for their remarkable activity, with GI₅₀ values of 29 nM and 25 nM, respectively. The inhibitory effects of the most potent hybrids 6e, 6i, 10d, 10e, and 10g on EGFR were assessed. Compounds 6i and 10e exhibited greater potency than erlotinib as EGFR inhibitors. Compounds 6i and 10e were also examined for their apoptotic potential, revealing that these compounds promote apoptosis by activating caspase-3, caspase-8, and Bax, while down-regulating the anti-apoptotic protein Bcl-2. Molecular docking experiments are thoroughly examined to validate the binding interactions of the most active hybrids, 6i and 10e, with the EGFR active site. Furthermore, our new study examined the ADME properties of the new hybrids.

Cyclic di-guanosine monophosphate (c-di-GMP) acts as a second messenger regulating bacterial behaviors including cell cycling, biofilm formation, adhesion, and virulence. Monitoring c-di-GMP levels is crucial for understanding these processes and designing inhibitors to combat biofilm-related antibiotic resistance. Here, we developed a genetically encoded biosensor, cdiGEBS, based on the transcriptional activity of the c-di-GMP-responsive transcription factor MrkH. Notably, cdiGEBS can detect both low and high cellular c-di-GMP levels, with a high fluorescence dynamic change of 23-fold. Moreover, it can detect subtle changes in c-di-GMP concentrations due to variations in the expression of c-di-GMP synthesis or degradation enzymes and can distinguish different synthesis activities among WspR mutants. These capabilities allow us to apply cdiGEBS for identifying new diguanylate cyclases and evaluating chemicals that modulate c-di-GMP levels, highlighting its potential as a high-throughput tool for screening inhibitors of c-di-GMP synthesis enzymes. Overall, cdiGEBS enhances the study of c-di-GMP-regulated functions and holds the potential for screening antimicrobials targeting c-di-GMP or its synthesis enzymes.