Frontiers in Chemistry最新文献

The use of green solvents, citric acid (CA), and natural deep eutectic solvents (NADES) for the obtention of pectin from wastes (pulp and peel) of Malus domestica was studied. The NADES used comprised citric acid-glucose-water (N1) or lactic acid-glucose-water (N2). The fractions rich in pectin obtained after exposure to NADES showed lower yield (≈4 g/100 g CA vs. ≈ 11 g/100 g CA), equal to or lower degree of methoxylation (53-71 mol/100 mol CA vs. 73 mol/100 mol CA), equal to or greater content of uronic acid (50-63 g/100 g CA vs. 51 g/100 g CA) than those isolated with CA, and the ones obtained from peel were the most thermally stable. These pectins showed greater linearity, shorter branch lengths, and lower arabinose content than those obtained with CA. The neutral sugars present in the highest concentration in all the isolated fractions were arabinose, xylose, galactose, and rhamnose. Glucose was also detected, probably due to contamination with starch. Their aqueous solutions showed pseudoplastic behavior. The effect of ultrasound assistance was preliminarily evaluated in the production of pectic fractions using N2, observing higher yields (13-18 g/100 g), in general, a higher concentration of uronic acid and a higher degree of methoxylation when compared with the extraction without US. They also showed greater arabinose content (less degradative treatment), lower glucose content (increased purity), and higher rhamnogalacturonan I (RG-I) content. It is known that RG-I is linked to pectin bioactivity and rheological behavior. The green solvent techniques assayed allowed obtaining fractions rich in uronic acid with different chemical, thermochemical, and rheological characteristics. In the case of isolation with NADES, the yield was low, but preliminary tests with ultrasound assistance showed that it is possible to overcome this limitation.

Perovskite solar cells (PVSCs) show remarkable potential due to their high-power conversion efficiencies and scalability. However, challenges related to stability and long-term performance remain significant. Self-assembled monolayers (SAMs) have emerged as a crucial solution, enhancing interfacial properties, facilitating hole extraction, and minimizing non-radiative recombination. This review examines recent advancements in SAMs for PVSCs, focusing on three key areas: anchoring groups and interface engineering, electronic structure modulation as well as band alignment, and stability optimization. We emphasize the role of anchoring groups in reducing defects and improving crystallinity, alongside the ability of SAMs to fine-tune energy levels for more effective hole extraction. Additionally, co-adsorbed SAM strategies was discussed which can enhance the durability of PVSCs against thermal and moisture degradation. Overall, SAMs present a promising avenue for addressing both efficiency and stability challenges in PVSCs, paving the way toward commercial viability. Future research should prioritize long-term environmental durability and the scaling up of SAM applications for industrial implementation.

Within the context of the circular economy, the transformation of agri-food waste or by-products into valuable products is essential to promoting a transition towards more sustainable and efficient utilisation of resources. Whey is a very abundant by-product of dairy manufacturing. Apart from partial reutilisation in animal feed or some food supplements, the sustainable management and disposal of whey still represent significant environmental challenges. In this work, whey is considered a valuable resource for producing high-value products, specifically 2,3-butanediol (2,3-BDO), which was produced through fermentation using the bacterial strain Lactococcus lactis 43103. The described process yielded a >90% purity of 2,3-BDO, which was evaluated as a potential chain extender in the synthesis of bio-based waterborne polyurethane dispersions (PUDs). The incorporation of whey-derived 2,3-BDO led to the development of PUDs with up to 90% bio-based content without detrimental effects on the process or liquid-phase properties. The combination of 100% bio-based polyether polyols with partially renewable L-lysine ethyl ester diisocyanate and whey-derived 2,3-BDO as a chain extender generated totally stable, low-particle-size water dispersions of amorphous polymers characterised by similar structure and molecular weight compared to those of alternative petroleum-based PUDs. These results open up the possibility of incorporating fermentation-derived 2,3-BDO as a totally renewable component in bio-based PUDs as potential sustainable resinous systems for further formulation of water-based coatings or adhesives.

Cannabinoid and stilbenoid compounds derived from Cannabis sativa were screened against eight specific fungal protein targets to identify potential antifungal agents. The proteins investigated included Glycosylphosphatidylinositol (GPI), Enolase, Mannitol-2-dehydrogenase, GMP synthase, Dihydroorotate dehydrogenase (DHODH), Heat shock protein 90 homolog (Hsp90), Chitin Synthase 2 (CaChs2), and Mannitol-1-phosphate 5-dehydrogenase (M1P5DH), all of which play crucial roles in fungal survival and pathogenicity. This research evaluates the binding affinities and interaction profiles of selected cannabinoids and stilbenoids with these eight proteins using molecular docking and molecular dynamics simulations. The ligands with the highest binding affinities were identified, and their pharmacokinetic profiles were analyzed using ADMET analysis. The results indicate that GMP synthase exhibited the highest binding affinity with Cannabistilbene I (-9.1 kcal/mol), suggesting hydrophobic solid interactions and multiple hydrogen bonds. Similarly, Chitin Synthase 2 demonstrated significant binding with Cannabistilbene I (-9.1 kcal/mol). In contrast, ligands such as Cannabinolic acid and 8-hydroxycannabinolic acid exhibited moderate binding affinities, underscoring the variability in interaction strengths among different proteins. Despite promising in silico results, experimental validation is necessary to confirm therapeutic potential. This research lays a crucial foundation for future studies, emphasizing the importance of evaluating binding affinities, pharmacokinetic properties, and multi-target interactions to identify promising antifungal agents.

As an agricultural planting practice, preceding cropping can not only enhance soil fertility and reduce pests and diseases but also boost crop yield and quality. In this study, SZS samples from different preceding cropping areas were selected as research subjects. Phenolic compounds were analyzed using high-performance liquid chromatography (HPLC), and antioxidant activities were assessed based on free radical scavenging effects. Variety differences were explored through chemical pattern recognition, and the spectrum-effect relationship between the fingerprint spectra of SZS and antioxidant activity was investigated using Pearson correlation analysis, grey relational analysis, and other methods. A total of 17 peaks were observed, among which 4 peaks were identified. They are gallic acid, catechin, spinosin, and scutellarin. The 22 SZS samples could be categorized into 3 groups, with cluster analysis and principal component analysis results being largely consistent. Spinosin, a marker compound of SZS, is a crucial contributor to the total antioxidant activity. In conclusion, the spectrum-effect relationship between phenolic compounds and the antioxidant activity of SZS was established, and the main characteristic components affecting antioxidant activity were identified, providing a reference for the quality evaluation of SZS and the development of its products.

Introduction: Dengue Fever continues to pose a global threat due to the widespread distribution of its vector mosquitoes, Aedes aegypti and Aedes albopictus. While the WHO-approved vaccine, Dengvaxia, and antiviral treatments like Balapiravir and Celgosivir are available, challenges such as drug resistance, reduced efficacy, and high treatment costs persist. This study aims to identify novel potential inhibitors of the Dengue virus (DENV) using an integrative drug discovery approach encompassing machine learning and molecular docking techniques.

Method: Utilizing a dataset of 21,250 bioactive compounds from PubChem (AID: 651640), alongside a total of 1,444 descriptors generated using PaDEL, we trained various models such as Support Vector Machine, Random Forest, k-nearest neighbors, Logistic Regression, and Gaussian Naïve Bayes. The top-performing model was used to predict active compounds, followed by molecular docking performed using AutoDock Vina. The detailed interactions, toxicity, stability, and conformational changes of selected compounds were assessed through protein-ligand interaction studies, molecular dynamics (MD) simulations, and binding free energy calculations.

Results: We implemented a robust three-dataset splitting strategy, employing the Logistic Regression algorithm, which achieved an accuracy of 94%. The model successfully predicted 18 known DENV inhibitors, with 11 identified as active, paving the way for further exploration of 2683 new compounds from the ZINC and EANPDB databases. Subsequent molecular docking studies were performed on the NS2B/NS3 protease, an enzyme essential in viral replication. ZINC95485940, ZINC38628344, 2',4'-dihydroxychalcone and ZINC14441502 demonstrated a high binding affinity of -8.1, -8.5, -8.6, and -8.0 kcal/mol, respectively, exhibiting stable interactions with His51, Ser135, Leu128, Pro132, Ser131, Tyr161, and Asp75 within the active site, which are critical residues involved in inhibition. Molecular dynamics simulations coupled with MMPBSA further elucidated the stability, making it a promising candidate for drug development.

Conclusion: Overall, this integrative approach, combining machine learning, molecular docking, and dynamics simulations, highlights the strength and utility of computational tools in drug discovery. It suggests a promising pathway for the rapid identification and development of novel antiviral drugs against DENV. These in silico findings provide a strong foundation for future experimental validations and in-vitro studies aimed at fighting DENV.

[This corrects the article DOI: 10.3389/fchem.2023.1271176.].