Solvents Acetone Research Articles

Analysis of PH, foam stability, and antioxidant activity in soap formulation from extract of pedada leaves (Sonneratia caseolaris) and pandan leaves (Pandanus amaryllifolius)

Plant-based antioxidant soap formulations need to continue to be developed. Soap formulated from extracts of pedada leaves (Sonneratia caseolaris) and pandan leaves (Pandanus amaryllifolius) has been observed using 5-15 mL acetone or ethanol solvents for pedada leaf extraction, and extract concentrations of 0-40% and cocamide-DEA 2-8% for pandan leaves. The formulation results obtained from observing soap products from pedada leaf and pandan leaf extracts have pH, foam stability, antioxidant activity, and detergency power that comply with standards. Contour plot analysis for both formulations shows that the pH of the soap will decrease as the amount of solvent used decreases. Meanwhile, the addition of cocamide DEA increases the pH of liquid soap. Foam stability increases with increasing solvent amount but slightly decreases with the addition of cocamide-DEA.

Guide for Nonequilibrium Molecular Dynamics Simulations of Organic Solvent Transport in Nanopores: The Case of 2D MXene Membranes.

Organic solvent nanofiltration (OSN) stands out as an energy-efficient and low-carbon footprint technology, currently reliant on polymeric membranes. With their exceptional chemical stability and tunable sieving properties, two-dimensional (2D) nanolaminate membranes present distinct advantages over conventional polymer-based membranes, attracting tremendous interest in the OSN community. Computational approaches for designing innovative 2D nanolaminates exhibit significant potential for the future of OSN technology. Imitating the pressure gradient in filtration processes by applying an external force to atoms within a predefined slab, boundary-driven nonequilibrium molecular dynamics ((BD)-NEMD) is a state-of-the-art simulation method with a proven track record in investigating the water transport in nanopores. Nevertheless, implementation of (BD)-NEMD for a broad range of solvents poses a challenge in estimating the OSN performance of theoretical membranes. In this work, we developed a (BD)-NEMD protocol that elucidates the effects of several computational details often overlooked in water simulations but are crucial for bulky solvent systems. We employed a MXene (Ti3C2O2) nanochannel as a model membrane and examined the transport of nine solvents (methanol, ethanol, acetone, n-hexane, n-heptane, toluene, ethyl acetate, dichloromethane, and water) having different properties. First, the impact of ensemble type, thermostatting, channel wall model, and restraining force constant was elaborated. After optimizing the thermostatting approach, we demonstrated that the location of the force slab particularly affects the flux of bulky solvents by changing the density distribution in the feed and permeate sides. Similarly, the uniformity of intramolecular force distribution in bulky solvents and resulting flux are shown to be prone to manipulation by slab boundaries. Next, the magnitudes of the external force generating a linear relation between the pressure gradient and solvent flux were identified for each solvent to ensure that calculated fluxes could be extrapolated to experimentally related pressures. This linear relation was also validated for a mixture system containing 50% ethanol and 50% water. We then correlated the calculated solvent permeances with various solvent properties, such as viscosity, Hansen solubility parameters, kinetic diameter, and interaction energy. Remarkably, we observed a linear correlation with an R2 value of 0.96 between permeance and the combined parameter of viscosity and interaction energy. Finally, the solvent permeances calculated with our proposed methodology closely align with the experimentally reported data. Overall, our work aims to serve as a practical guide and bridge the gap in established simulation methods that are suited for a broad range of solvents and membrane materials.

Solvent-Mediated Rate Deceleration of Diels–Alder Reactions for Enhanced Selectivity: Quantum Mechanical Insights

Solvents can have a tremendous influence on the rate and selectivity of chemical reactions, but their effects are not always well accounted for. In the present work, density functional theory computations are used to investigate the influence of solvent on the Diels–Alder reactions of 9-methylanthracene with (5-oxo-2H-furan-2-yl) acetate and different anhydrides considering the overall reaction rates as well as selectivity between possible isomeric products. Crucially, we find that overall reaction rates are higher in non-polar toluene, whereas selectivity is enhanced in the polar solvent acetone. In the case of (5-oxo-2H-furan-2-yl) acetate, the difference in the reaction barriers is enhanced by 2.4 kJ/mol in acetone as compared to the gas phase, halving the yield of the side product. Similar results are found for the reaction of 9-methylanthracene with chloro-maleic anhydride and cyano-maleic anhydride, highlighting the generality of the trends observed. After presenting the energetics, a detailed discussion of the reactivity is given using electrostatic potentials, frontier orbitals, reactivity indices and Fukui functions. In summary, this study highlights the importance of solvent in influencing reaction rates and illustrates the possibility of studying its effects computationally.

Self-Repairable Carbon Fiber-Reinforced Epoxy Vitrimer Actuator with Multistimulus Responses and Programmable Morphing.

Smart shape-changing structures in aerospace applications are vulnerable to damage in harsh environments. Balancing high mechanical performance with self-repair capabilities poses a challenge due to inherent trade-offs between strength and flexibility. To address this challenge, an asymmetric bilayer-structured actuator was fabricated using commercially available continuous carbon fiber tows (CFs) as the passive layer and a dynamic cross-linked epoxy vitrimer as the active layer. The construction of the vitrimer-CF actuator involves a simple and scalable hot-pressing process, resulting in a tensile strength of 234 MPa and an interfacial bonding strength of 405 N·m-1. This actuator exhibits remarkable deformation capability (210°/7 s) and an efficient self-repair ability under various stimuli, including thermal (60-160 °C), light (0.4-1.0 W·cm-2), electric (2-4 V), and solvent (acetone). By adjustment of the orientation angle of CFs, complex left-handed and right-handed curling structures can be achieved. Leveraging the insights from photothermal/electrothermal actuation mechanisms, a quadruped crawling robot is developed capable of crawling 4 cm with a single light illumination. The actuator can lift objects 45 times its weight when subjected to light stimuli. Additionally, a flap actuator is constructed to achieve an angle change of 63° within 10 s under an electric stimulus, enabling remote control over the aircraft flight angle. These results demonstrate the potential of the vitrimer-CF actuator for advanced applications in intelligent aerospace structures.

Qualitative phytochemical analysis of bioactive constituents in acetone extract of seeds of Hydnocarpus pentandra

Ethnoveterinary medicine focuses on the practical use of community or area based traditional and indigenous knowledge including the collection, preparation and administration of medicinal plants or plant parts for curing diseases of animals. Hydnocarpus pentandra is a plant endemic to South India which is traditionally known for the antileprotic activity of its seed oil. Diverse pharmacological activities of the plant extracts depend on the presence of its secondary metabolites. The present research was conducted to explore the phytochemical constituents present in the acetone solvent extract of the seeds of H. pentandra. Preliminary phytochemical screening of the extract using colorimetric reactions revealed the presence of steroids, triterpenes, diterpenes, flavonoids, alkaloids and carbohydrates. Gas chromatography-mass spectrometry (GC-MS) analysis revealed the presence of different compounds which included paromomycin, D-streptamine, carnegine, 4-propyl acridine and R-limonene. The acetone extract could be considered as a potent source of new molecules with different pharmacological actions. Keywords: Hydnocarpus pentandra, phytochemical screening, secondary metabolites

Electronic structure, global reactivity descriptors and nonlinear optical properties of glycine interacted with ZnO, MgO and CaO for bacterial detection

Modern laboratory medicine relies on analytical instruments for bacterial detection, focusing on biosensors and optical sensors for early disease diagnosis and treatment. Thus, Density Functional Theory (DFT) was utilized to study the reactivity of glycine interacted with metal oxides (ZnO, MgO, and CaO) for bacterial detection. Total dipole moment (TDM), frontier molecular orbitals (FMOs), FTIR spectroscopic data, electronic transition states, chemical reactivity descriptors, nonlinear optical (NLO) characteristics, and molecular electrostatic potential (MESP) were all investigated at the B3LYP/6–31G(d, p) level using DFT and Time-Dependent DFT (TD-DFT). The Coulomb-attenuating approach (CAM-B3LYP) was utilized to obtain theoretical electronic absorption spectra with the 6-31G(d, p) basis set to be more accurate than alternative quantum chemical calculation approaches, showing good agreement with the experimental data. The TDM and FMO investigation showed that glycine/CaO model has the highest TDM (10.129Debye) and lowest band gap (1.643 eV). The DFT computed IR and the experimental FTIR are consistent. The calculated UV-vis spectra showed a red shift with an increase in polarity following an increase in the absorption wavelength due to the interaction with ZnO, MgO, and CaO. Among the five solvents of water, methanol, ethanol, DMSO and acetone, the water and DMSO enhances the UV-Vis absorption. Glycine/CaO model showed high linear polarizability (14.629 × 10−24esu) and first hyperpolarizability (23.117 × 10−30esu), indicating its potential for nonlinear optical applications. The results showed that all model molecules, particularly glycine/CaO, contribute significantly to the development of materials with potential NLO features for sensor and optoelectronic applications. Additionally, MESP confirmed the increased electronegativity of the studied structures. Additionally, glycine/ZnO nanocomposite was synthesized and characterized using IR and UV-visible spectroscopy to determine their structural and spectroscopic features. It was discovered that there was good agreement between the DFT computed findings and the related experimental data. The antibacterial activity of glycine/ZnO nanocomposites against Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa were studied in terms of concentration and time. The results showed that increasing the concentration of glycine/ZnO nanocomposite significantly enhanced its antibacterial efficacy by lowering optical density. Notably, Pseudomonas aeruginosa exhibited lower susceptibility to the nanocomposite compared to S. aureus, requiring higher concentrations for effective bactericidal action. In summary, this study contributes novel insights into the dual functionality of glycine-metal oxide complexes, with significant implications as optical biosensor for microbial detection.

Effect of Temperature on Rotational Dynamics of 3BT7D2H-one in Acetone and Ethyl Acetate Solvents.

The rotational dynamics of 3-(benzo[d]thiazol-2-yl)-7-(diethylamino)-2H-chromen-2-one (3BT7D2H-one) in two non-polar solvents acetone and ethyl acetate have been studied with varying temperatures. The rotational dynamics follow follows the Stoke's-Einstein-Debye (SED) model in ethyl acetate solvent but shows deviation in acetone solvent when temperature is increased. Quasi-hydrodynamic models Gierer and Wirtz (GW) model and Dote-Kivelson Schwartz (DKS) is studied in a qualitatively way.

Polyglycerol Sebacate/polycaprolactone/reduced graphene oxide composite scaffold for myocardial tissue engineering

The aim of this research was to fabricate and evaluate polyglycerol sebacate/polycaprolactone/reduced graphene oxide (PGS-PCL-RGO) composite scaffolds for myocardial tissue engineering. Polyglycerol sebacate polymer was synthesized using glycerol and sebacic acid prepolymers, confirmed by Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). Six PGS-PCL-RGO composite scaffolds (S1-S6) with various weight ratios were prepared in chloroform (CF) and acetone (Ace) solvents at 8 CF:2Ace and 9 CF:1Ace volume ratios, using the electrospinning method at a rate of 1 ml/h and a voltage of 18 kV. The scaffolds' chemical composition and microstructure were characterized by FTIR, XRD, and scanning electron microscopy (SEM). Further investigations included tensile testing, contact angle testing, four-point probe testing for electrical conductivity, degradation testing, and cytotoxicity testing (MTT). The results showed that adding 2%wt RGO to the composite scaffold decreased fiber diameter and degradation rate, while increasing electrical conductivity and ductility. The 33%PGS-65%PCL-2%RGO (S3) composite scaffold exhibited the lowest degradation rate (23.87 % over 60 days) and the highest electrical conductivity (51E-3 S/m). Mechanical evaluations revealed an elastic modulus of 2.46 MPa and elongation of 62.43 %, aligning closely with the heart muscle's elastomeric properties. The contact angle test indicated that the scaffold was hydrophilic, with a water contact angle of 61 ± 2°. Additionally, the cell toxicity test confirmed that scaffolds containing RGO were non-toxic and supported good cell viability. In conclusion, the 33%PGS-65%PCL-2%RGO composite scaffold exhibits mechanical and structural properties similar to heart tissue, making it an ideal candidate for myocardial tissue engineering.

Ultrasonic-Assisted Water-Rich Natural Deep Eutectic Solvents for Sustainable Polyphenol Extraction from Seaweed: A Case Study on Cultivated Saccharina latissima.

This case study introduces a green, 1 h single-step method using water-rich natural deep eutectic solvent (WRNADES) for ultrasound-assisted extraction (UAE) of polyphenols fromSaccharina latissima, a commercially cultivated brown seaweed. The extraction efficiency was evaluated using a selective quantitative NMR method (s-qNMR) and the traditional nonselective colorimetric total phenolic content assay (TPC). Initial 6 h extractions in traditional solvents (methanol, ethanol, acetone, and ethyl acetate) showed a 40-60% increase in polyphenolic yields in 50% aqueous solutions measured by the TPC method. Six different water-rich (50%) NADES (WRNADES) combinations were tested (choline chloride/betaine with lactic acid, citric acid, and 1,3-butanediol), with betaine and 1,3-butanediol (1:1) proving most effective. Parameters for the WRNADES were optimized using Box-Behnken design response surface methodology, resulting in a 1:20 w/w biomass to solvent ratio and a 1 h extraction time at 50 °C. The WRNADES extraction process was refined into a scalable, single-step procedure and compared with traditional solvent extractions (6 h, 50% aqueous methanol and acetone). A final XAD-7 polyphenol recovery step was included in all extractions. The optimized WRNADES extraction yielded 15.97 mg GAE/g of the dry weight recovered polyphenolic extract (s-qNMR), exceeding the 6 h 50% aqueous methanol (12.4 mg GAE/g) and acetone (11.4 mg GAE/g) extractions. Thus, the UAE-WRNADES method presented in this case study provides a cost-effective, sustainable, and eco-friendly alternative for the extraction of phenolic compounds from seaweed. It promotes the development of environmentally friendly production processes within the seaweed biorefinery.

Integrative process of extraction and purification of tagitinin C using ethanolic two-phase system based on protic ionic liquids

Tithonia diversifolia is a tropical plant composed of several compounds with medicinal properties. This study aimed to design a sequential process for the extraction of tagitinin C from T. diversifolia using organic solvents (acetone, acetonitrile, methanol, and ethanol) and purification in the ethanolic two-phase system (ETPS) formed by protic ionic liquids (PILs), polypropylene glycol 2000 (PPG-2000) and ethanol, reported here for the first time. The extraction process variables such as type of solvent, solid–liquid ratio, temperature, and process time were evaluated. Ethanol was the best tagitinin C extracting agent (702.1 µg/mL). Phase diagrams were constructed using PPG-2000, PIL, and ethanol at 298.15 K. The sequencing with the purification process occurred by adding the other constituents directly into the ethanol extract. Tagitinin C preferentially migrated to the top phase (rich in PPG-2000), while phenolic compounds (contaminants) were partitioned mainly to the opposite phase (PIL-rich phase). ETPS formed by [2HEA][Ac] (15.52 wt%) + PPG 2000 (49.91 wt%) + ethanol (34.57 wt%) at 298.15 K presented the highest selectivity (S = 18.3), extraction efficiency in the top phase (EE% = 86 %) and purification factor (3.4-fold), demonstrating the ability of ETPS to selectively and sequentially extract and purify tagitinin C.

Chemical characterization of heat‐treated kraft lignin after fractionation with organic solvents and pH effect

AbstractLignin, the main source of renewable aromatics, has a complex structure, high polydispersity, and low reactivity, which hinders its large‐scale use. This study aims to improve lignin reactivity through heat treatment combined with fractionation by organic solvents or the pH effect. Heat treatment of commercial hardwood black liquor was performed at 225 °C for 150 min. The samples were then fractionated either by using organic solvents (ethyl acetate, ethanol, methanol, and acetone) or by lowering pH using hydrochloric acid (HCl) (pH values 1, 3, 5, 7, and 9). The fractionation was carried out in one step and in sequential mode. The fractionated samples were characterized chemically by the content of acid‐soluble and acid‐insoluble lignin, carbohydrates, ash, inorganic compounds (metals), elemental analysis, and by pyrolysis‐gas chromatography–mass spectrometry (Py‐GC–MS). The highest mass yields were obtained using the one‐step mode for both fractionations, with yields as high as 53.3% for organic solvents and 47.8% for the pH effect. Solvent fractionation reduced ash content by up to 75.4% and increased calorific value, carbon content, and total lignin content. Fractionation by pH effect showed an ash reduction of up to 55.9% and an increase in calorific value and carbon content of up to 8.7 MJ kg−1 and 49.7%, respectively. The Hansen solubility parameters were also calculated to address lignin's solubility in each of the tested solvents. These findings indicate that combining heat treatment and fractionation techniques improves lignin's chemical properties significantly, making it a more viable raw material for industrial use. This approach supports the circular economy by transforming lignin into a high‐value product, thereby promoting sustainable and efficient resource utilization across industries.

Efficient epoxidation of styrene over single-atomic copper-doped ordered mesoporous alumina (Cu-OMA) composited with carbon nitride

The present study assessed the catalytic performance in epoxidation of styrene using tert‑butyl hydroperoxide (TBHP) as an oxidant over single-atomic copper-doped Ordered mesoporous alumina (Cu-OMA) composited with g-C3N4 (CN). The thermal treatment at three temperatures (300, 500, 700 °C) provided a facile mean to modify the texture and electronic structure of the Cu-OMA@CN composite. The X-Ray absorption spectroscopy proved the single-atomic Cu-O-Al and Cu-O-C in Cu-OMA@CN-500 catalyst. Catalytic reaction parameters, namely temperature (60–80 °C), catalyst amount (10–70 mg), substrate/oxidant ratio (1:1–1:3), and solvents (acetone, ethanol, acetonitrile, N, N-dimethylacetamide) were optimized to obtain high conversion of styrene and selectivity to styrene epoxide. Under the optimized reaction conditions (75 °C, 30 mg of catalyst, 1:2 of styrene/TBHP and acetonitrile as solvent), the conversion decreased in the order of Cu-OMA@CN-500 > Cu-OMA@CN-300 > Cu-OMA@CN-700. This sequence was related to the formation of electron-rich single-atom copper sites, high surface area, medium alkaline environment and high content of graphic nitrogen species in Cu-OMA@CN-500. This structure differed from the blocky structure of C3N4 in Cu-OMA@CN-300 and the destroyed tri-s-triazine ring in Cu-OMA@CN-700. The most active Cu-OMA@CN-500 catalyst displayed a high styrene conversion (87.2 %) and striking selectivity to styrene oxide (90.0 %). Its catalytic activity was retained after five recyclability tests. The possible catalytic mechanism for epoxidation of styrene over this catalyst was tentatively proposed.

Exploring grape pomace extracts for the formulation of new bioactive multifunctional chitosan/alginate-based hydrogels for wound healing applications

Chronic wounds incidence is increasing and affects millions of people around the world, causing great psychological and socio-economic impacts. However, treatments that can effectively promote wound healing are still lacking. In this study, grape pomace (GP), the main residue from winemaking production was explored as a source of high added-value raw material directed for the topical treatment of Staphylococcus aureus chronic wound infections. Crude GP extracts (composed of stalks or a skin and seeds mixture–from red and white grape varieties) obtained using a modified solid-liquid extraction (water, ethanol, and acetone solvents) were evaluated for their antioxidant capacity (ABTS and DPPH assays), as well as the richness of phenolic compounds (total phenolic content-TPC, total flavonoid content-TFC, and HPLC-DAD assays). The GP extracts with the most favorable results were incorporated in a chitosan-alginate hydrogel (cross-linked with glutaraldehyde and calcium chloride), characterized (swelling, degradation, and release properties), and tested for its bioactivity (antioxidant and antimicrobial potential). TPC and TFC were higher in red GP extracts, as confirmed by the HPLC analysis, indicating a greater diversity of compounds in these extracts. Ethanolic white GP extracts (from skin-seeds mixture) showed the highest extraction yield and antioxidant activity. Their incorporation into the chitosan-alginate hydrogel improved its swelling and antimicrobial properties (total cytoplasmic membranes disruption and culturability reduction). A biomaterial with high swelling capacity and antibacterial activity against S. aureus was obtained, which can potentially promote wound healing by exudate absorption and infection clearance while promoting valorization of by-products and stimulating a circular economy.

Insecticidal and Anti-Feedant Activity of Clerodendrum Extracts on Growth and Development of Castor Spiny Caterpillar, Ariadne merione

The castor spiny caterpillar Ariadne merione (F.) is a major lepidopteran pest affecting castor (Ricinus communis) crops mainly by causing defoliation which in turn reduces the photosynthesis and yield. The conventional pest control methods have been based on chemical control which although has been effective, has its drawbacks of being hazardous to the environment and human health besides leading to resistance by the pests. The present work aims at investigating the possibility of using Clerodendrum inerme, a plant belonging to the Lamiaceae family, as an eco-friendly solution for pest management. Insecticidal and anti-feedant efficacy of C. inerme leaf extracts, which were prepared using solvents hexane, acetone, and petroleum ether, was tested against A. merione larvae using leaf dip bioassay under no-choice situation. The findings showed that the hexane extract had the highest insecticidal (73%) and anti-feedent (97%) action. The petroleum ether extract also showed moderate insecticidal (50%) and anti-feedant activity (48%) but not as potent as the acetone extract having insecticidal and anti-feedant action of 60 and 74 per cent respectively. The results imply that C. inerme extracts, especially the hexane extract, could be used as botanical insecticides in IPM programs as a natural replacement for chemical insecticides.

Phytochemical screening, antibacterial, antioxidant, and cytotoxic activities of Geranium pusillum leaves.

Traditional medicinal plants play an important role in primary health care worldwide. The phytochemical screening and activities of Geranium pusillum were investigated in this research. The dried plant leaves were extracted with ethanol, n-hexane, chloroform, dichloromethane, methanol, acetone, and aqueous solvents. These extracts were qualitatively analyzed, GC-MS, antimicrobial activities by using the disc diffusion method, antioxidant activity was determined by 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) radical scavenging, and cytotoxic activity was analyzed by the hemolytic activity of human red blood cells. The results showed phytochemicals such as flavonoids, terpenoids, steroids, phenols, saponins, tannins, and cardiac glycosides were detected in plant leaves. The ethanol extract at a concentration of 10 mg/mL showed a maximum inhibition zone 17.5 ± 0.09, 15.6 ± 0.11, 14.2 ± 0.17, 18.4 ± 0.11, 16.6 ± 0.15, 12.5 ± 0.13, 15.9 ± 0.10, and 13.1 ± 0.11 mm, and at 15 mg/mL showed 24.5 ± 0.09, 27.2 ± 0.12, 26.3 ± 0.17, 28.4 ± 0.10, 27.9 ± 0.16, 22.5 ± 0.13, 27.1 ± 0.10, and 24.1 ± 0.16 mm against Escherichia coli, Pasturella multocida (gram-negative), Staphylococcus aureus, Bacillus subtilus (gram-positive), Rhizopus solani, Aspergillus flavus, Aspergillus niger, and Alternaria alternate (fungal strain), respectively, and dichloromethane showed a minimum inhibition zone as compared to other extracts against bacterial as well as fungal strains. Chloroform extract had maximum antioxidant activity (45.00 ± 0.08%) and minimum in dichloromethane (12.20 ± 0.04%). Cytotoxic activity was found maximum in acetone extract (19.83 ± 0.07%) and minimum in ethanol extract (4.72 ± 0.04%). It is concluded that phytochemicals like phenols, flavonoids, and others may be responsible for these activities, which is why this plant is used for traditional medicine. RESEARCH HIGHLIGHTS: Geranium pusillum has therapeutic properties that exhibit various biological activities beneficial for human health. G. pusillum has significant inhibitory effects against bacterial and fungal strains. Chloroform solvent extract indicates potential free radical scavenging abilities. Acetone extract exhibits notable effects on human red blood cells and demonstrates significant cytotoxic activity.

Ab initio electronic absorption spectra of para-nitroaniline in different solvents: Intramolecular charge transfer effects.

Intramolecular charge transfer (ICT) effects of para-nitroaniline (pNA) in eight solvents (cyclohexane, toluene, acetic acid, dichloroethane, acetone, acetonitrile, dimethylsulfoxide, and water) are investigated extensively. The second-order algebraic diagrammatic construction, ADC(2), ab initio wave function is employed with the COSMO implicit and discrete multiscale solvation methods. We found a decreasing amine group torsion angle with increased solvent polarity and a linear correlation between the polarity and ADC(2) transition energies. The first absorption band involves π → π* transitions with ICT from the amine and the benzene ring to the nitro group, increased by 4%-11% for different solvation models of water compared to the vacuum. A second band of pNA is characterized for the first time. This band is primarily a local excitation on the nitro group, including some ICT from the amine group to the benzene ring that decreases with the solvent polarity. For cyclohexane, the COSMO implicit solvent model shows the best agreement with the experiment, while the explicit model has the best agreement for water.

Solvent-Focused Gas Chromatographic Determination of Thymol and Carvacrol Using Ultrasound-Assisted Dispersive Liquid-Liquid Microextraction through Solidifying Floating Organic Droplets (USA-DLLME-SFO).

An ultrasound-assisted dispersive liquid-liquid microextraction by solidifying floating organic droplets, coupled to a form of temperature-programmed gas chromatography flame ionization detection, has been developed for the extraction and determination of thymol and carvacrol. This method utilizes undecanol as the extraction solvent, offering advantages such as facilitating phase transfer through solidification and enhancing solvent-focusing efficiency. The optimal gas chromatography conditions include a sample injection volume of 0.2 µL, a split ratio of 1:10, and a flow rate of 0.7 mL min-1. The extraction conditions entail an extraction solvent volume of 20 µL, a disperser solvent (acetone) volume of 500 µL, pH 7.0, 7.0% NaCl (3.5 M), a sample volume of 5.0 mL, an ultrasound duration of 10 min, and a centrifuge time of 7.5 min (800 rpm). These conditions enable the achievement of a high and reasonable linear range of 3.5 to 70. 0 μg mL-1 for both thymol and carvacrol. The detection limits are found to be 0.95 and 0.89 μg mL-1, respectively, for thymol and carvacrol. The obtained relative standard deviations, 2.7% for thymol and 2.6% for carvacrol, demonstrate acceptable precision for the purpose of quantitative analysis.

Evaluation of Differences in Solubility in Organic Solvents of Softwood/Hardwood-Based Industrial Kraft Lignins Using Hansen Parameters and FTIR

Abstract: Lignin is part of the lignocellulosic biomass found in hardwoods, softwoods, and herbaceous plants. It is isolated by fractionation and pulping processes, where it is considered a waste product and is mainly burned to generate electricity and heat. However, lignin is a biopolymer that can be a source of many chemicals of significant value after treatments of functionalisation or depolymerisation. The main processes for its valorisation require solubilisation in organic solvents, which may affect the process’s mass balance and the biopolymer’s chemical structure, as lignins are rarely completely soluble in organic solvents. In this research, two industrial Kraft lignins derived from softwood and hardwood were treated using different green organic solvents (2-methyl tetrahydrofuran, tetrahydrofuran, 1-methoxy-2-propanol, and acetone), measuring the soluble and insoluble content to determine the mass balance, and the solubility was evaluated using Hansen parameters and FTIR. The results showed that both lignins were more soluble in tetrahydrofuran and 1-methoxy-2-propanol. Also, tetrahydrofuran performed better than the 2-methyl tetrahydrofuran, which is considered the green alternative. The reason can be explained using the Hansen solubility parameters. Moreover, the solubilised fractions showed similar FTIR spectra. The same is the case for the insoluble parts. In conclusion, the two lignins studied showed different solubilities in absolute values in organic solvents, but the trends were similar.

The impact of thermophysical properties on eflornithine drug solute in acetone and ethyl acetate solvent interactions at varying concentrations and temperatures

The study was conducted on the impact of thermophysical properties on eflornithine drug solute–solvent interactions in aqueous ethyl acetate and acetone at different concentrations and temperatures. The aim of this study is to enhance the understanding of eflornithine’s behavior in different solvents, which is crucial for its effective use in pharmaceutical applications. The density, molar volume, viscometric, and conductometric characteristics of the eflornithine drug solutions (0.025, 0.05, 0.075, 0.1, and 0.125 mol/kg) in acetone and 25% (v/v) aqueous ethyl acetate were measured within a temperature range of 298.15 K–318.15 K. Based on the determined density parameters, the following parameters were assessed: viscosity (η), equivalent molar conductance, limiting apparent molar volume (V0φ), apparent molar volume of transfer (V0φtr), and apparent molar volume (Vφ). The Masson empirical relationship and the viscosity-to-Jones-Dole (JD) equation were used to evaluate the partial molar volume (Vφ), experimental slope (SV), viscosity, and density data. Temperature and concentration were used to determine each parameter. For each set of dilutions, conductometric studies were conducted in both study solvents. The gathered data was analyzed in order to evaluate the ion–solvent interactions. The Walden product Λomηo’s positive temperature coefficient values indicate that the drug eflornithine functions as a structural modifier in acetone and aqueous acetyl acetate systems. The structure-making and breaking characteristics of the polar solvents acetone and ethyl acetate were identified.

Enhanced Curculigoside and Phenolic Compounds Elevate Antioxidant Activity in C. orchioides Gaertn In Vitro Under Exogenous Augmentation with Elicitors Salicylic Acid (SA) and Polyethylene Glycol (PEG) 6000

Abstract Introduction Curculigo orchioides Gaertn, an endangered medicinal plant, possesses a bioactive compound known as curculigoside (phenolic glycoside) in addition to other phenolic compounds. Curculigoside has multifunctional pharmacological properties including antioxidant and anti-inflammatory. Advances in plant tissue culture provide us with tools for the in vitro propagation of medicinal plants in addition to a well-founded system to enhance pharmacologically bioactive compounds through the use of elicitors. Objective The study evaluates the effect of exogenous application of salicylic acid (SA) and polyethylene glycol 6000 (PEG 6000) to in vitro cultures of C. orchioides for enhanced curculigoside, phenolic compounds production followed by an increase in antioxidant activity (AA). Method Eight-week-old subcultured plants grown in one-fourth strength Murashige and Skoog media were subjected to elicitors treatment. SA (10, 100, and 1,000 ppm) and a PEG 6000 (1,000, 5,000, and 10,000 ppm) were used as elicitors for a period of 1, 2, and 4 weeks. Plants without treatment were considered as control. The treated plants were subjected to 80% acetone solvent for efficient phenolic extract preparation. High-performance liquid chromatography was used for the analysis of curculigoside content (CC), and total phenolic content (TPC) was determined using the Folin–Ciocalteu colorimetric method. AA was evaluated by 1,1-diphenyl-2-picrylhydrazyl assay. Results SA treatment increased CC, TPC, and biological activity of AA properties compared to the control, with the maximum value observed at 10 ppm treatment after week 1 elicitation. CC, TPC, and AA gradually decreased after week 2 elicitation, and the lowest values were observed after week 4 elicitation. In the PEG 6000 treatment, 10,000 ppm elicited the highest CC and TPC, with the maximum AA observed after week 2 elicitation. The treatment also elicited higher CC, TPC, and AA in both the 1st and 4th weeks compared to the control. Conclusion SA and PEG 6000 successfully enhanced CC, TPC, and improved AA in C. orchioides in vitro. The study also offers insightful information for the neutraceutical, cosmeceutical, and pharmaceutical industries about how to potentially manipulate medicinal plants in vitro to increase the synthesis of bioactive compounds.