Chemical Papers最新文献

Tree leaves could be a source of α-bisabolol, a sesquiterpene alcohol with broad application in the fine chemistry industry, mainly for encapsulating water-insoluble compounds. This study evaluated the presence of α-bisabolol in extracts from pitanga leaves of the red and purple varieties. The extracts were obtained using traditional extraction techniques (Soxhlet and hydrodistillation) and pressurized extraction with SC-CO₂ (under 50 and 60 °C; 150 and 250 bar) and pressurized n-propane (under 30, 45, and 60 °C; and 40, 60, and 80 bar), under constant flow rate (3 and 5 cm³ min⁻¹, respectively), followed by an adsorption step on three different solid phases (alumina, Amberlit®, and silica). The oil yield of the red and purple varieties followed the descending order in the Soxhlet (5.44 and 5.70%) > SC-CO₂ (1.74 and 1.48%) > pressurized n-propane (1.39 and 0.94%) > and hydrodistillation (0.22 and 0.18%). Although less expressive, the extract obtained with pressurized n-propane required milder operating conditions, which were more suitable for the evaluated conditions. The fractionation columns with stationary phases were not selective in purifying α-bisabolol. Sovová's mathematical model adequately fitted oil extraction kinetics for both solvents (average R² of 0.997 for SC-CO₂ and 0.955 for pressurized n-propane). The results showed that all the oils obtained from red and purple varieties of pitanga leaves using pressurized extractions presented the compound α-bisabolol, which had not been reported in the literature. These extracts are an alternative for adding value to the fruit waste.

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Wet chemical combination of Hibiscus rosa-sinensis flower extract and selenous acid (H₂SeO₃) resulted in biogenic Selenium(0) nanoparticles. The chemical bottom-up approach was used to produce piperine-loaded flavonoid surface-capped Selenium(0) nanoconjugates. These Selenium(0) nanoparticles and piperine-loaded nanoconjugates were characterized using ultraviolet–visible absorption studies, Fourier-transform infrared spectroscopy, and photoluminescence emission spectroscopic techniques to confirm the formation of nanoparticles. The crystallite sizes, packing, and morphologies of Selenium(0) and piperine-loaded Selenium(0) nanoconjugates were determined from X-ray diffraction (XRD) patterns and transmission electron microscopy analysis. The XRD analysis had exhibited the amorphous nature of nanoconjugates with mean size 56 nm. After confirmation of physiochemical properties of piperine-loaded Selenium(0) nanoconjugates, primary in vitro synergistic biocompatibility was studied and compared with free drug piperine over E. coli and Staphylococcus aureus. The neuroprotective effects of nanoconjugates were estimated by in vitro MTT assay and eosin dye staining images of Parkinson neural cell lines with SH-SY5Y model. These nanoconjugates had exhibited synergistic antimicrobial and neuroprotective effects to repair of neuron peroxide damaged cells from cell viability on Parkinson model cells with good biomedical potential.

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The adsorptive performance of divalent manganese onto single-walled carbon nanotubes (SWCNTs) is investigated by X-ray absorption spectroscopy (XAS). The study is focused on the one hand, on the use of SWCNT as adsorbent to remove divalent manganese II) pollutant controlling batch parameters such as pH, adsorbent dose and contact time; and on the other hand, on the characterization of manganese adsorbed by SWCNT (Mn-SWCNT) adsorbent to probe the chemical composition, oxidation state, and local structural environment of Mn absorber. Freundlich adsorption isotherm well fitted the experimental data and suggested the maximum adsorption capacity at pH 2. Ion exchange was proposed as the main adsorption mechanism for removing manganese using SWCNT. XAS results revealed the change in the oxidation state of manganese. The effect of pH, adsorbent dose, and contact time is shown. XAS also showed that Mn-SWCNT material is principally composed of MnCl₂, Mn₂O₃, MnO₂, Mn₃O₄, and MnO in decreasing order with MnCl₂ and Mn₂O₃ as major compounds.

Alkaloids, flavonoids, tannins, and essential oils present in flowers demonstrate exceptional effectiveness in preventing corrosion. These moieties adsorb onto metal surfaces, creating a protective barrier that minimizes interaction with corrosive environments. Flower extracts are gaining recognition as eco-friendly corrosion inhibitors because of their natural abundance, affordability, and minimal environmental impact. This article delves into the essential elements of leveraging flower extracts for corrosion prevention, covering their working mechanisms, varieties of extracts employed, preparation techniques, efficacy, and possible uses.

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Oxygen gas is a vital element for many physical and chemical processes and its generation is a key feature to enhance and sustain a broad range of applications. A small-scale laboratory pressure swing adsorption (PSA) unit was built for concentrated oxygen generation and investigated for the best operating conditions. Key parameters such as oxygen recovery, air factor, and bed size factor are necessary to measure the performance of the PSA process. These are affected by product flow rate, PSA cycle duration, required oxygen purity, applied pressure, and type of adsorbent used. Li-LSX zeolite at constant applied pressure, was used as the main adsorbent for nitrogen in this study under different operating conditions. Results show that a best duration time for both the pressurization and depressurization cycle was found to be 12 s for all flow rates that is ranging from 1 lpm up to 10 lpm. It was found that oxygen recovery would increase directly from 0.05 up to 0.27 with product flow rate range 1–8 lpm, respectively. However, after 8 lpm, a slight decrease in the recovery value was reported. Air factor changes inversely with product flow rate, shows sharp increase at low flow rates and levels off approaching a constant value of ≈ 15 when flow rate become more than 8 lpm. Bed size factor of 400 kg.d/t_O2 was found to be the optimum value to obtain oxygen concentration > 90%.

This study reports the development and evaluation of an eco-friendly lip balm enriched with standardized botanical extracts (chamomile (Matricaria chamomilla) and green tea (Camellia sinensis)) targeting skin hydration and antioxidant protection. Grape seed oil, barberry powder, beeswax, glycerin, and vitamin E were incorporated to enhance moisturization and stability. Four formulations were prepared under Good Manufacturing Practices (GMP) conditions and assessed for physicochemical stability (pH, viscosity, color), moisturizing efficacy, antioxidant capacity (2,2-Diphenyl-1-picrylhydrazyl (DPPH) assay, Ferric Reducing Antioxidant Power (FRAP) assay), and spreadability. The formulation containing 15% total extracts (F3) demonstrated superior performance, showing a 34.6% increase in hydration, 50.5% DPPH inhibition, and a FRAP value of 116.2 µmol Trolox equivalents per gram (µmol TE/g). Patch testing on 90 volunteers confirmed excellent skin compatibility, with no signs of irritation. Comparative analysis against commercial herbal lip balms highlighted F3’s significantly higher antioxidant and hydration performance. The correlation between FRAP values and skin hydration (r = 0.91) suggests synergistic functionality of polyphenols in barrier repair and oxidative protection. These findings support the integration of green chemistry principles in high-performance dermocosmetic formulations, offering a validated and sustainable alternative for natural lip care products.

An eco-friendly approach was employed to develop cobalt ferrite (CoFe₂O₄) nanoparticles (CF MNPs) and graphene oxide (GO) based CoFe₂O₄ magnetic nanocomposites (GO-CF MNCs) using star anise fruit extract (SAFE) as a natural reducing and stabilizing agent. GO was synthesized via an improved Hummer’s method, while CF MNPs and GO-CF MNCs were prepared through a green co-precipitation route. The active involvement of SAFE in nanoparticle formation was confirmed through Fourier Transform Infrared (FT-IR) spectroscopy, which showed a significant reduction in the intensity of phytochemical functional groups alongside the appearance of new characteristic bands confirming the formation of CF MNPs and GO-CF MNCs. Structural and morphological analyses was done using X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, Dynamic light scattering (DLS), and UV–visible (UV–Vis) spectroscopy. The comparative adsorption performance of CF MNPs and GO-CF MNCs for the methylene blue (MB) dye was investigated, with an emphasis on pH, contact time, and surface charge interactions. The point of zero charge (pH@PZC) for GO-CF MNCs was determined, supporting the adsorption mechanism. Time-dependent studies revealed that GO-CF MNCs achieved a significantly higher removal efficiency (97%) than CF MNPs (89%) within 180 min. These findings underscore the potential of GO-CF MNCs as highly efficient, magnetically recoverable, and sustainable adsorbents for wastewater treatment applications.

A novel nanocomposite, Bentonite-TiO₂ Quantum Dots (BTQD), meticulously designed for the photocatalytic degradation of Brilliant Blue R (BBR) dye, a representative contaminant in textile wastewater. The BTQD material was synthesized utilizing a co-precipitation technique, which effectively promoted a uniform distribution of TiO₂ quantum dots (TQD) upon the bentonite support. This strategic functionalization resulted in a significant enhancement of the specific surface area to 212.25 m²/g for the BTQD, a substantial increase over pristine bentonite, thereby augmenting the density of active sites crucial for pollutant adsorption and photocatalytic efficacy. Characterization using transmission electron microscopy confirmed the TQD possessed an average particle size of 5–8 nm, a dimension optimal for leveraging quantum size effects to bolster photocatalytic activity and have an intermediate optical bandgap of 3.00 eV, facilitating photocatalytic processes under both UV and visible light irradiation. X-ray diffraction patterns verified the anatase crystalline phase of the TiO₂ component, which is well-established for its high photocatalytic efficiency. The photocatalytic degradation of BBR dye using the BTQD composite was systematically evaluated, revealing adherence to first-order reaction kinetics. Furthermore, the material displayed excellent stability and recyclability, maintaining robust degradation efficiency over successive operational cycles, which is a critical factor for practical wastewater treatment applications. Concomitantly, significant reductions in chemical oxygen demand (COD) and total organic carbon (TOC) were observed post-treatment, indicating extensive mineralization of organic pollutants. This work presents a promising and economically viable pathway for the remediation of industrial effluents containing recalcitrant organic dyes and associated contaminants.

The increasing demand for biocompatible and effective wound-healing solutions has driven research into natural, antimicrobial-based dressings. Thus, growing concern about antibiotic resistance has led to exploring alternative infection treatments. By adding honey (HY) and Piper longum aqueous extract (PLAE) to chitosan (CHI)-based films, this study seeks to improve wound healing. The solvent casting method was used to create these films, which were then thoroughly examined utilizing SEM, FTIR, XRD, water transmission investigations, and dynamic mechanical examination. Additionally, histological examinations and rabbit wound-healing studies were used to evaluate their biodegradation, antibacterial activity, hemolytic qualities, and in vivo efficacy. The findings showed strong potential for wound healing, indicating that these films might be used as cutting-edge material for wound dressings. These films have a lot of potential for commercialization as bioactive wound dressings because of their natural composition and antibacterial effectiveness. Their use in the medical and pharmaceutical sectors may provide a viable and efficient substitute for traditional wound treatment methods.

Coal-fired power plants are among the largest contributors of CO₂ emissions, highlighting the need for sustainable energy solutions. Photocatalytic process is an innovative and sustainable approach for reducing CO₂ emissions from coal-burning processes, utilizing crab shell-derived materials as catalysts. The aquaculture sector disposes of approximately 40% of fish waste, the Crustacean trade generates 6–8 million tons of shell trash every year worldwide. Calcium carbonate (CaCO₃) from crab shell are transformed into effective photocatalysts through thermal modifications. The processed crab shell was examined by Fourier transform infrared spectroscopy, particle size analysis, thermogravimetric analysis, scanning electron microscopy and energy-dispersive X-ray spectroscopy. The crab shell-based calcium oxide nanoparticle catalysts have a wide surface area and active sites that capture and transform CO₂ under UV light exposure. The integration of crab shell-based photocatalysts for removal of CO₂ from flue gas offers a dual advantage: valorization of seafood waste and reduction of greenhouse gases. The maximum CO₂ removal efficiency achieved was 74% with 40–50 min of irradiation. This work lies in converting naturally abundant crab shell waste into calcium oxide nanoparticles with high CO₂ adsorption and reduction potential, thereby integrating waste valorization with environmental remediation. This research aligns with Sustainable Development Goals (SDG) 9 and 13 emphasizing innovation in sustainable materials and climate action.