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In situ electrochemical potential-induced fast synthesis the ultrathin MAF-4 membrane on polymer support with a satisfactory H 2 /CO 2 separation performance and excellent stability. [Display omitted] Metal-Organic Framework (MOF) membranes act as selective layers have offered unprecedented opportunities for energy-efficient and cost-effective gas separation. Searching for the green and sustainable synthesis method of dense MOF membrane has received huge attention in both academia and industry. In this work, we demonstrate an in situ electrochemical potential-induced synthesis strategy to aqueously fabricate Metal Azolate Framework-4 (MAF-4) membranes on polypropylene (PP) support. The constant potential can induce the heterogeneous nucleation and growth of MAF-4, resulting an ultrathin membrane with the thickness of only 390 nm. This high-quality membrane exhibits a high H 2 /CO 2 separation performance with the H 2 permeance as high as 1565.75 GPU and selectivity of 11.6. The deployment of this environment friendly one-step fabrication method under mild reaction conditions, such as low-cost polymer substrate, water instead of organic solvent, room temperature and ambient pressure shows great promise for the scale-up of MOF membranes. [ABSTRACT FROM AUTHOR]

As a biodegradable and biocompatible polymer material, polyglycolic acid is attracting more and more attention in the field of polymeric and biomedical materials. Consequently, the study of the transformation between different crystal forms of glycolide, the monomer of polyglycolic acid, is of great importance, because crystal forms of glycolide determine the stabilities and properties of polyglycolic acid products polymerized under different conditions in industry. Herein, this article reports the synthesis and crystallization of α‐ and β‐glycolide controlled by the type of organic solvents and/or temperatures, during which an intermediate crystal form of β′‐glycolide is newly observed. The transformation between α‐, β‐, and β′‐glycolide is investigated in detail, and the stabilities of different crystal forms are illustrated via the controlled experiments under different relative humidity (RH) as well as the theoretical calculations, which should provide fundamental concepts and guidance for the industrial production of glycolide and optimization of polyglycolic acid products. [ABSTRACT FROM AUTHOR]

This work highlighted the proficient and naturally safe methodology for the phenol synthesis using biocatalyst lipase. The development of sustainable synthetic protocol for various organic transformations is an important area of research attracts researchers to avoid use of volatile and hazardous organic solvents in reaction for greener and eco-friendly protocols. Lipase is subclass of esterase enzymes and acts as biocatalyst with industrial significance. They carry out biochemical transformation in non-aqueous and aqueous phases quickly. To further make the process more specific Design Expert software was used for the optimization of synthesize phenol for maximum % Yield and % Purity. Effect of temperature, Concentration of Catalyst, and Volume of Water was selected as an independent factor to get the maximum % Yield and % Purity of the phenol. The results confirmed the mathematical model robustness and justify experimental design. Therefore, the current protocol for synthesis of phenols from phenylboronic acid is greenest and environmentally benign alternative. The current convention has many benefits, like phenomenal product yields, reduced time of reaction, simple procedure to work up, and extensive substrate scope, cost-effective and also lipase was recuperated and reused multiple times without significant loss of its catalytic activity. [ABSTRACT FROM AUTHOR]

Photoactive supramolecular porphyrin assemblies are attractive molecules for light‐harvesting applications. This is due to their relatively non‐toxicity, biological activities and charge and energy exchange characteristics. However, the extreme cost associated with their synthesis and requirements for toxic organic solvents during purification pose a challenge to the sustainability characteristics of their applications. This work presents the first report on the sustainable synthesis, spectroscopic and photophysical characterizations of a near‐infrared (NIR) absorbing Ca(II)‐meso‐tetrakis (4‐hydroxyphenyl)porphyrin using an electrolyzed pyrrole solution. The latter was obtained by cycling the pyrrole solution across the silver nanodumbbell particle surface at room temperature. The electrolyzed solution condensed readily with acidified p‐hydroxybenzaldehyde, producing the targeted purple porphyrin. The non‐electrolyzed pyrrole solution formed a green substance with significantly different optical properties. Remarkable differences were observed in the voltammograms of the silver nanodumbbell particles and those of the conventional gold electrode during the pyrrole cycling, suggesting different routes of porphyrin formation. The rationale behind these formations and the associated mechanisms were extensively discussed. Metalation with aqueous Ca2+ ion caused a Stokes shift of 38.75 eV. The current study shows the advantage of the electrochemical method towards obtaining sustainable light‐harvesting porphyrin at room temperature without the need for high‐energy‐dependent conventional processes. [ABSTRACT FROM AUTHOR]

Vegetable oils are rich in health-beneficial compounds, including fatty acids, phenolic compounds, natural antioxidants, and fat-soluble vitamins. However, oil extraction methods can influence their composition. This study aims to understand the chemical basis for developing a green process to extract oils from two Andean seeds, cañihua (Chenopodium pallidicaule) and tarwi (Lupinus mutabilis). Ethanol, considered a green solvent, is compared to petroleum ether used at the laboratory level and hexane used at the industrial scale for extracting oils. The extraction efficiency is assessed in terms of yield, fatty acids profile, polar and neutral lipids, tocopherols, phenolic compounds, and antioxidant capacity. The chemical composition of edible commercial oils, such as sunflower, rapeseed, and olive oils, was used as a reference. Hexane had the highest extraction yield, followed by petroleum ether and ethanol. However, the oils extracted with ethanol having yields of tarwi 15.5% and cañihua 5.8%, w/w showed the significatively superior content of tocopherols (α, γ, and δ); phenolic compounds; and antioxidant capacity. In addition, ethanol-extracted (EE) oils have higher levels of polar lipids, such as phosphatidylcholine and phosphatidylinositol, than those extracted with the other solvents. Remarkably, EE oils presented comparable or slightly higher levels of monounsaturated fatty acids than those extracted with hexane. Finally, compared to the commercial oils, tarwi and cañihua EE oils showed lower but acceptable levels of oleic, linoleic and palmitic acids and a wider variety of fatty acids (10 and 13, respectively). The composition of tarwi and cañahua oils extracted with ethanol includes compounds associated with nutritional and health benefits, providing a sustainable alternative for oil production. [ABSTRACT FROM AUTHOR]

The mutual separation of Am and Cm is conducted using an alkyl-diamide amine (ADAAM(EH)) extractant. ADAAM(EH) exhibits an extremely high separation factor (SF) with respect to Am and Cm separation (SF = 5.9) in an HNO3-n-dodecane system. The batch-wise multistage extractions are performed using a system containing 0.2 M ADAAM(EH) and 1.5 M HNO3, with their distribution ratios (D) of the system for Am and Cm equal to 2.55 and 0.434, respectively. In this multistage extraction, 3 stages of feed, 9 stages involving scrubbing, and 11 stages involving the use of an organic solvent give 96.5% and 1.06% yields of Am and Cm, respectively. After the mutual separation, the aqueous and the organic phases including actinides increase four times in volume compared to the feed solution. Additional extraction steps are to reduce the volume of the solutions including actinides. We use tetraethyl diglycolamide (TEDGA)/water for Am concentration, tetraoctyl diglycolamide/n-dodecane for the intermediate extraction, and TEDGA/water for stripping in the Cm concentration step. Taking the additional steps, Am and Cm can be recovered in just two or three stages in the aqueous phases. [ABSTRACT FROM AUTHOR]

Essential oils are emerging as alternatives to conventional pest control chemicals. Lippia graveolens Kunth (Mexican oregano) is a source of essential oils and during conventional extraction, the biomass generated is discarded as waste; however, reports show that this biomass is still a rich source of essential oils. Conventional essential oil extraction causes contamination and utilizes toxic solvents. Deep eutectic solvents (DESs) offer low toxicity, biodegradability, high selectivity, and yields comparable to organic solvents. This study obtained essential oil from Lippia graveolens biomass via hydrodistillation with ultrasound-assisted DES pretreatment. This research aimed to optimize the extraction of essential oil from Lippia graveolens biomass using ultrasound-assisted DESs and assess its in vitro and in vivo inhibitory effect on C. asianum. The response variables were extraction yield and total reducing capacity. Optimal conditions were determined using a central composite rotatable design, considering solid-to-liquid ratio (0.38 g/mL), ultrasonic amplitude (45.05%), and time (7.47 min). The optimized oil, with thymol (48%) as the predominant component, exhibited more volatile compounds than conventional hydrodistillation. Fungicidal assays highlighted its potential in controlling anthracnose in papaya fruits caused by C. asianum, making ultrasound-assisted DES pretreatment a promising alternative for obtaining essential oil from botanical byproducts. [ABSTRACT FROM AUTHOR]

We demonstrate liquid-jet photoelectron spectroscopy from a flatjet formed by the impingement of two micron-sized cylindrical jets of different aqueous solutions. Flatjets provide flexible experimental templates enabling unique liquid-phase experiments that would not be possible using single cylindrical liquid jets. One such possibility is to generate two co-flowing liquid-jet sheets with a common interface in vacuum, with each surface facing the vacuum being representative of one of the solutions, allowing face-sensitive detection by photoelectron spectroscopy. The impingement of two cylindrical jets also enables the application of different bias potentials to each jet with the principal possibility to generate a potential gradient between the two solution phases. This is shown for the case of a flatjet composed of a sodium iodide aqueous solution and neat liquid water. The implications of asymmetric biasing for flatjet photoelectron spectroscopy are discussed. The first photoemission spectra for a sandwich-type flatjet comprised of a water layer encapsulated by two outer layers of an organic solvent (toluene) are also shown. [ABSTRACT FROM AUTHOR]

In this novel attempt to enhance the removal of oils and organic solvents from wastewater, making water safer and cleaner for use, poly(ethylene-co-vinyl acetate was blended with organically modified montmorillonite (OMMT) nanoclay following a green pathway by melt blending in a Brabender plasticoder. The prepared nanocomposites exhibited excellent adsorption capacity for various oils and organic solvents. To further increase the adsorption capacity of the nanocomposites, NaCl was added as a porogen in the melt mixing process, followed by the leaching of NaCl in water to generate a highly porous nanocomposite material. The adsorption tests revealed excellent efficiency, with an adsorption capacity of 40 g g−1 in dichloromethane (DCM), 11 g g−1 in gasoline, and 5 g g−1 in crude oil. The nanocomposites demonstrated excellent recycling capability and could be reused for more than 30 adsorption–desorption cycles. FTIR, XRD, SEM, and TEM analyses were conducted to delineate the structure and morphology of the nanocomposite. [ABSTRACT FROM AUTHOR]

Existing adsorption materials with drawbacks in the weak organic solvents/oil retention ability, slow adsorption speed and low adsorption capacity for alkanes still hardly meet demands of the application field, especially in emergencies. The copolymerization of the long‐chain alkenes, 1‐octene, with isoprene was designed in this paper to synthesize an adsorption resin (PIOT), instead of acrylate monomers reported in the literature. And trimethylolpropane triacrylate was designed as a crosslinking agent. Results show that the PIOT grows in the form of powders, which are the loose accumulation of nanoflakes with a diameter of about 47.89 ± 11.06 nm. In view of the chain structure and morphology of the PIOT, it can quickly reach the maximum adsorption within 10 s along with a high adsorption capacity for various solvents and kerosene. Even for hexane, the adsorption capacity of the PIOT increases by 345.2% compared with the reported adsorption resin. The oil retention rate of PIOT can be maintained at 86 ± 6% after centrifugation at 1000–3000 rpm for 5–25 min. Compared with commercial activated carbon, the PIOT has outstanding advantages in recycling property and oil retention rate and compared with the reported acrylate adsorption resin, the PIOT has made a great breakthrough in adsorption capacity for alkanes. [ABSTRACT FROM AUTHOR]

Laccases act as green catalysts for oxidative cross-coupling of phenolic antioxidnt compounds, but low stability and non-recyclability limit its application. To address that, metal–organic frameworks Cu-BTC and Cr-MOF were synthesized as supports to immobilize the efficient laccase from Cerrena sp. HYB07. The Brunauer–Emmett–Teller surface area of Cu-BTC and Cr-MOF were 1213.2 and 907.1 m2/g, respectively. The two carriers respectively presented pore diameters of 1.2–10 nm and 1.4–12 nm as octahedron, indicating nano-scale mesoporosity. These Cu-BTC and Cr-MOF carriers could adsorb laccase with enzyme loading of 1933.2 and 1564.4 U/g carrier, respectively. The stability and organic solvent tolerance of Cu-BTC-laccase and Cr-MOF-laccase were both obviously improved compared to free laccase. Thermal inactivation kinetics showed that both the two immobilized laccases displayed lower thermal inactivation rate constants. Importantly, the Cu-BTC-laccase and Cr-MOF-laccase both showed much higher activity for cross-coupling of ethyl ferulate than free laccase, which had 2.5-fold higher cross-coupling efficiency than that by free laccase. The ethyl ferulate coupling product was also analyzed by mass spectroscopy and the synthesis pathway of ethyl ferulate dimer was proposed. The cross coupling of ethyl ferulate required the formation of radical intermediates of ethyl ferulate generated by laccase mediated oxidation. This work paved the way for MOFs immobilized laccase for cross coupling of antioxidant phenols. [ABSTRACT FROM AUTHOR]

Tomato peel by-products contain high levels of lycopene, which has traditionally been extracted using organic solvents. This research focuses on the optimisation of a sustainable method to obtain a lycopene-rich extract using the biodegradable anionic surfactant sodium dodecyl sulphate (SDS). A Plackett–Burman experimental design was used to investigate the effect of seven factors on the extraction of carotenoids from tomato peels using sodium dodecyl sulphate (SDS volume and concentration, homogenisation intensity and time, sonication phase, extraction time and ultracentrifugation intensity). Based on the responses of total carotenoid extraction, the SDS volume, the use of ultrasound and the extraction time significantly influenced the extraction yield and were selected for optimisation using a Box–Wilson experimental design. The final green extraction protocol (1 g sample + 11.9 ml SDS 0.3%, homogenisation at 13,500 rpm for 2 min, ultrasound phase, agitation for 8.2 h and ultracentrifugation) was selected after quantification of total carotenoids by UV–VIS and HPLC-DAD. Finally, we used nuclear magnetic resonance to demonstrate a high lycopene purity in the carotenoid extract obtained. Furthermore, using transmission electron microscopy, we observed the presence of intact chromoplasts in the extract, protecting the carotenoids from the exposure to external agents. Thus, this work reports an optimised method for the sustainable extraction of carotenoids and demonstrates the viability of the degradable solvent SDS for the extraction of liposoluble bioactive compounds, like carotenoids and mainly lycopene. The lycopene extract could be used for the technological and nutritional enrichment of new foods and/or the design of nutraceuticals. [ABSTRACT FROM AUTHOR]

A novel and efficient method has been developed for synthesizing benzothioamide from benzonitrile in supercritical CO2, which could be used to synthesize various benzothioamide derivatives efficiently with yields of up to 98% without the need for organic solvent. Notably, some H2S-based salts were designed and prepared, and they were found to be effective catalysts in promoting the thiolysis of benzonitrile to produce benzothioamide in an excellent yield. Furthermore, the utilization of supercritical CO2 as a solvent has demonstrated a remarkable increase in the yield of the desired product compared to conventional solvents for promoting benzonitrile thiolysis. Additionally, the investigation of the reaction mechanism has revealed that the acid–base properties of the reaction solution played a crucial role in the thiolysis of benzonitrile mediated by the H2S-based salts. [ABSTRACT FROM AUTHOR]

Cross-linkable hole-transporting materials with a new cross-linking group, benzocyclobutene, are designed and synthesized. These materials dissolve well in common organic solvents and exhibit excellent solvent resistance after thermal cross-linking. Electroluminescent (EL) devices were fabricated using these two hole-transporting materials. [ABSTRACT FROM AUTHOR]

A novel and efficient method has been developed for synthesizing benzothioamide from benzonitrile in supercritical CO2, which could be used to synthesize various benzothioamide derivatives efficiently with yields of up to 98% without the need for organic solvent. Notably, some H2S-based salts were designed and prepared, and they were found to be effective catalysts in promoting the thiolysis of benzonitrile to produce benzothioamide in an excellent yield. Furthermore, the utilization of supercritical CO2 as a solvent has demonstrated a remarkable increase in the yield of the desired product compared to conventional solvents for promoting benzonitrile thiolysis. Additionally, the investigation of the reaction mechanism has revealed that the acid–base properties of the reaction solution played a crucial role in the thiolysis of benzonitrile mediated by the H2S-based salts. [ABSTRACT FROM AUTHOR]

In this work, we presented the results of density functional theory calculations for the static first hyperpolarizability for one representative push–pull π‐conjugated molecule, 2‐dimethylamino‐7‐nitrofluorene, in six organic solvents (p‐dioxane, chloroform, tetrahydrofuran, acetone, acetonitrile, and dimethylsulfoxide) spanning a large range of dielectric constant. The finite‐field formalism was used to calculate the longitudinal component of the static first hyperpolarizability. The solvent effect was calculated using two distinct polarizable continuum solvation models: the linear response and the state‐specific polarizable continuum models. The calculations demonstrated the existence of solvation model effects on the property of interest, which warranted further analysis. The two‐level model was then employed to illustrate the impact of solvation model. Our findings suggested that the state‐specific polarizable continuum model gave a decrease of the dipole moment of the excited state in high polarity solvent for a bathochromic molecule whose excited state should have a larger polarization than its ground state. [ABSTRACT FROM AUTHOR]

Understanding solvent‐solute interactions is essential to designing and synthesising soft materials with tailor‐made functions. Although the interaction of the solute with the solvent mixture is more complex than the single solvent medium, solvent mixtures are exciting to unfold several unforeseen phenomena in supramolecular chemistry. Here, we report two unforeseen pathways observed during the hierarchical assembly of cationic perylene diimides (cPDIs) in water and amphiphilic organic solvent (AOS) mixtures. When the aqueous supramolecular polymers (SPs) of cPDIs are injected into AOS, initially kinetically trapped short SPs are formed, which gradually transform into thermodynamically stable high aspect ratio SP networks. Using various experimental and theoretical investigations, we found that this temporal evolution follows two distinct pathways depending on the nature of the water‐AOS interactions. If the AOS is isopropanol (IPA), water is released from cPDIs into bulk IPA due to strong hydrogen bonding interactions, which further decreases the monomer concentration of cPDIs (Pathway‐1). In the case of dioxane AOS, cPDI monomer concentration further increases as water is retained among cPDIs (Pathway‐2) due to relatively weak interactions between dioxane and water. Interestingly, these two pathways are accelerated by external stimuli such as heat and mechanical agitation. [ABSTRACT FROM AUTHOR]

The preparation of highly rigid cobalt(II)- and copper(II)–organic frameworks incorporating a tetralactam [2]rotaxane as a ligand is described. The interlocked ligand is functionalized with two pairs of carboxylate groups placed at each counterpart, thus limiting its dynamics within the crystal. The solid structure of the metal–organic rotaxane frameworks showed different, unprecedented polycatenation modes of grids, depending on the employed metal, providing great rigidity to the structures. This rigidity has been evaluated by using single crystal X-ray diffraction analyses of the cobalt(II)–organic frameworks embedded in different solvents, observing that the lattices remain unchanged. Thus, this research demonstrates that rigid and robust materials with permanent porosity can be achieved using dynamic ligands. [ABSTRACT FROM AUTHOR]

One-dimensional dissolution of a layered compound in a nonpolar organic solvent is reported for the first time. A high-aspect ratio fluorohectorite modified with a cationic surfactant (dioctadecyldimethylammonium) showed spontaneous delamination into monolayer nanosheets in chloroform. [ABSTRACT FROM AUTHOR]

We report here on the reductive rearrangement of biomass-derived furfural to cyclopentanone, a promising non-fossil feedstock for fuels and chemicals. An underreported aspect of this reaction is the inevitable formation of heavy byproducts. To mitigate its formation, process condition such as, solvent, catalyst, temperature, acidity, and feed concentration were varied to unravel the chemistry and improve the reaction performance. Water medium was confirmed to play a crucial role, as organic solvents were unable to deliver cyclopentanone or heavy by products. Copper-based catalyst showed the highest selectivity for ring-rearrangement, reaching 50 mol% under the conditions investigated. The main factor influencing the yields of cyclopentanone (CPO), and promote oligomer formation, are the feed concentration and the pH, as high feed concentrations and high acidity facilitate the self-polymerization of furfuryl alcohol (FALC). This was confirmed by dedicated experiments using FALC and the hydroxypentenone intermediate as feed. The concentration challenge could be mitigated by slowly dosing the feed, which increased the desired product yields by 4-12 mol%. Nevertheless, most oligomers appeared to fall in the range of common liquid fuels and could be converted to diesel by hydrodeoxygenation. [ABSTRACT FROM AUTHOR]

Reductive amination of carbonyl compounds and nitro compounds represents a straightforward way to attain imines or secondary amines, but it is difficult to control the product selectivity. Herein, we report the selective formation of C−N or C=N bond readily manipulated through a solvent‐induced hydrogen bond bridge, facilitating the swift photocatalytic reductive coupling process. The reductive‐coupling of nitro compounds with carbonyl compounds using formic acid and sodium formate as the hydrogen donors over CdS nanosheets selectively generates imines with C=N bonds in acetonitrile solvent; while taking methanol as solvent, the C=N bonds are readily hydrogenated to the C−N bonds via hydrogen‐bonding activation. Experimental and theoretical study reveals that the building of the hydrogen‐bond bridge between the hydroxyl groups in methanol and the N atoms of the C=N motifs in imines facilitates the transfer of hydrogen atoms from CdS surface to the N atoms in imines upon illumination, resulting in the rapid hydrogenation of the C=N bonds to give rise to the secondary amines with C−N bonds. Our method provides a simple way to control product selectivity by altering the solvents in photocatalytic organic transformations. [ABSTRACT FROM AUTHOR]

The biochemical composition and bioavailability of particulate organic matter (POM) were studied in relation to abiotic (water column stratification, macronutrient concentrations) and biotic factors (phytoplankton biomass and functional groups) in the open Ross Sea and coastal area of Terra Nova Bay, Antarctica, during the austral summer 2017. The presence of different sub-systems was highlighted by spatial and temporal variations of all the considered variables, characterised by higher concentrations of particulate organic carbon and nitrogen in Terra Nova Bay, where diatoms dominated, while in the open Ross Sea was higher the contribution of haptophytes (Phaeocystis antarctica Karsten, 1905). The southernmost Ross Sea was characterised by significantly higher concentrations of carbohydrates in the entire water column. High lipid contribution and low photosynthetic activity indicated aged POM, suggesting that POM was composed mainly by the remnants of previous haptophytes production. The higher lability of the carbohydrates indicated that an increase of haptophytes in the area could alter the biogeochemical C cycle, reducing the storage of refractory carbon in the depths, and favouring the transfer and respiration of C in the trophic web, with a decrease of export rate in the Ross Sea. [ABSTRACT FROM AUTHOR]

Organic solvent nanofiltration (OSN) has enormous potential for transforming the way organic solvents are purified and recovered in the chemical industry. Apart from conventional thin film composite (TFC) nanofiltration membrane fabrication methods, a greener, simpler, and more efficient approach has been utilized to fabricate OSN membranes. Oxidative polymerization of an aqueous solution of a pyrrole monomer on a hydrolyzed/crosslinked polyacrylonitrile (H-PAN/C-PAN) support yielded a dense polypyrrole (PPy) skin layer consisting of a conjugated carbonaceous polyaryl network. The presence of multiple amino groups (>NH) in the PPy chain develops extensive hydrogen bonding with the –COOH and –NH groups present in the H-PAN/C-PAN support. The shift in the ATR-FTIR peaks of PPy upon deposition on the H-PAN/C-PAN support confirmed the interaction between PPy and the H-PAN/C-PAN support. When the OSN performance of the fabricated membranes was studied, the PPy@C-PAN/PETP membrane showed a better performance in terms of rejection of model solutes including charged and neutral molecules compared to the PPy@H-PAN/PETP membrane. Both membranes rejected >99% of Rose Bengal, Congo red, and Eriochrome black T used as model solutes in the current study. For the neutral molecules, PPy@H-PAN@PETP was able to reject 44% of triphenylbenzene (TPB) and >99% of hexaphenylbenzene (HPB), whereas PPy@C-PAN@PETP rejected 72% of TPB and >99% of HPB. In the case of methylene blue, a rejection of 48% was found for PPy@H-PAN/PETP while a rejection of 82% was recorded for PPy@C-PAN/PETP. Moreover, the permeance of n-hexane was found to be 9.3 L m−2 h−1 bar−1 for PPy@H-PAN/PETP and 3.3 L m−2 h−1 bar−1 for the PPy@C-PAN/PETP membrane. [ABSTRACT FROM AUTHOR]

In this study, protonation constant values and liquid chromatographic behaviors of hydrophobic cyclizine, chlorcyclizine, hydroxyzine, cinnarizine, cetirizine, meclizine, and buclizine in some water‐organic solvent binary mixtures were examined for the first time using classical and green reverse phase liquid chromatography methods. In the isocratic study, the relationship of the retention time and mobile phase pH in water‐organic solvent binary mixtures containing acetonitrile (45, 50, 55, 60, 65%, v/v), methanol (60, 65, 70, 75%, v/v) and ethanol (45, 50, 55, 56, 59, 60, 62, 65%, v/v) were determined at 37 °C. In the study, XBridge C18 and Gemini NX C18 columns suitable for the chemical properties of basic compounds were used. The obtained liquid chromatographic data were analyzed using the linear solvation energy relationship methodology and the SOLVER program. The aqueous protonation constant values of the investigated compounds were calculated using the linear relationship between the protonation constant data calculated in studied binary mixtures and some macroscopic constant values of the solvents used. The greenness of methods developed using three different solvents was evaluated with the Analytical Greenness Metric Approach, the Green Analytical Procedures Index, and the Green Solvent Selection Tool approaches. [ABSTRACT FROM AUTHOR]

In the study, the synthesis process involved the reaction of dimethylolbutyric acid and polytetramethylene ether glycol 1000 (PTMG1000) with hexamethylene diisocyanate (H12MDI), taking advantage of their mutual dissolution at high temperatures. The chain‐extension reaction with 1,4‐butanediol (BDO) was successfully conducted without the use of organic solvents. The emulsification reaction was carried out using the polyurethane prepolymer at 60% solids content, along with aqueous dispersions of polyethylene glycol (PEG) with varying molecular weights and amounts as interfacially active agents. Fourier transform infrared spectroscopy analysis suggested potential hydrogen bonding interactions between the PEG molecular chain and the polyurethane chain. Rheometer analysis demonstrated a significant reduction in viscosity with the addition of 1–5 wt.% PEG, accompanied by an increase in average particle size. This phenomenon was attributed to the formation of a hydrophilic lubrication layer of PEG around the water‐based polyurethane (WPU) microcells. Among them, WPU films containing 4 wt.% PEG4000 not only exhibited soft properties with a mechanical elongation rate exceeding 2000% but also showed excellent storage stability. The addition of long‐chain PEG facilitated the formation of a lubrication layer between the microcells, contributing to spatial stabilization and reducing particle aggregation at high solids content. It is noteworthy that this solvent‐free process, without any organic solvents, together with the adjusted PEG content, successfully synthesized waterborne polyurethanes with low viscosity and high solids content. This provides a new sustainable and environmentally friendly method for the future production of waterborne polyurethanes. [ABSTRACT FROM AUTHOR]

Liquefaction conversion technology has become one of the hottest biomass conversion methods due to its flexible material selection and extensive product applications. Exploring biomass liquefaction conversion focuses on catalysts, biomass/water ratio, and reaction temperature. However, it is found that solvents are crucial in the biomass liquefaction process and significantly impact the type of liquefied products and bio-oil yield. Given the current rapid development trend, timely sorting and summary of the solvent effect in the biomass liquefaction process can promote the subsequent development and industrialization of more efficient and cleaner biomass liquefaction technology. Therefore, this review first introduces the characteristics of water as the liquefaction solvent, then summarizes the effects of organic solvents on liquefaction, and finally elaborates on the synergistic effect of co-solvents, which provides a more systematic overview of solvent effects in the liquefaction process. Meanwhile, prospects are put forward for the future development of biomass liquefaction conversion. [ABSTRACT FROM AUTHOR]

Conductive polymers, such as polyaniline (PANI), have interesting applications, ranging from flexible electronics, energy storage devices, sensors, antistatic or anticorrosion coatings, etc. However, the full exploitation of conductive polymers still poses a challenge due to their low processability. The use of compatible stabilizers to obtain dispersible and stable colloids is among the possible solutions to overcome such drawbacks. In this work, potato starch was used as a steric stabilizer for the preparation of colloidal polyaniline (emeraldine salt, ES)/starch composites by exploiting the oxidative polymerization of aniline in aqueous solutions with various starch-to-aniline ratios. The polyaniline/starch bio-composites were subjected to structural, spectroscopic, thermal, morphological, and electrochemical analyses. The samples were then tested for their dispersibility/solubility in a range of organic solvents. The results demonstrated the formation of PANI/starch biocomposites with a smaller average size than starch particles, showing improved aqueous dispersion and enhanced solubility in organic solvents. With respect to previously reported PANI-EB (emeraldine base)/starch composites, the novel colloids displayed a lower overall crystallinity, but the conductive nature of PANI-ES enhanced its electrochemical properties, resulting in richer redox chemistry, particularly evident in its oxidation behavior, as observed through cyclic voltammetry. Finally, as proof of the improved processability, the colloids were successfully integrated into a thin polyether sulfone (PES) membrane. [ABSTRACT FROM AUTHOR]

Pterocaulon polystachyum is a species of pharmacological interest for providing volatile and non-volatile extracts with antifungal and amebicidal properties. The biological activities of non-volatile extracts may be related to the presence of coumarins, a promising group of secondary metabolites. In the present study, leaves and inflorescences previously used for the extraction of essential oils instead of being disposed of were subjected to extraction with supercritical CO2 after pretreatment with microwaves. An experimental design was followed to seek the best extraction condition with the objective function being the maximum total extract. Pressure and temperature were statistically significant factors, and the optimal extraction condition was 240 bar, 60 °C, and pretreatment at 30 °C. The applied mathematical models showed good adherence to the experimental data. The extracts obtained by supercritical CO2 were analyzed and the presence of coumarins was confirmed. The extract investigated for cytotoxicity against bladder tumor cells (T24) exhibited significant reduction in cell viability at concentrations between 6 and 12 μg/mL. The introduction of green technology, supercritical extraction, in the exploration of P. polystachyum as a source of coumarins represents a paradigm shift with regard to previous studies carried out with this species, which used organic solvents. Furthermore, the concept of circular bioeconomy was applied, i.e., the raw material used was the residue of a steam-distillation process. Therefore, the approach used here is in line with the sustainable exploitation of native plants to obtain extracts rich in coumarins with cytotoxic potential against cancer cells. [ABSTRACT FROM AUTHOR]

This work investigated the spin states of the cobalt(II) complexes [Co(L1)2](X)2 (1·X; L1 = 4′-(4-N,N′-diphenylaminophenyl)-2,2′:6′,2′′-terpyridine, X = PF6, BPh4) and [Co(L2)2](X)2 (2·X; L2 = 4′-(4-N,N′-dimethylaminophenyl)-2,2′:6′,2′′-terpyridine, X = PF6, BPh4) in the solid state and in solution. In the solid state, 1·PF6 and 2·PF6, both containing smaller PF6− counter anions, showed gradual spin-crossover. In contrast, 1·BPh4 and 2·BPh4 remained in the high-spin state over the temperature range of 5–400 K due to a lower degree of molecular cooperativity. Each of the cobalt(II) complexes exhibited effects of temperature and concentration on their absorption spectra that were related to the spin states in various organic solvents. This work provides new insights into the spectroscopic properties resulting from the spin states of cobalt(II) complexes in solution. [ABSTRACT FROM AUTHOR]

Algae constitute a significant part of marine biodiversity. They represent a renewable source of bioactive metabolites from drug development and therapeutic fields. Fucoxanthin and β-carotene from the brown macroalgae Halopteris scoparia, were extracted using conventional organic solvent extraction, then purified, to homogeneity, based on various chromatographic principles. Their effects on digestive enzymes and harmful bacteria were investigated. The capacities of both purified pigments to inhibit α-amylase and trypsin enzymes were evaluated. Purified fucoxanthin and β-carotene exhibited interesting α-amylase inhibition activities, with IC50 of 300 and 500 µg/mL, respectively. Moreover, trypsin inhibition activities were detected using purified these two pigments. The antibacterial potential of the purified pigments was evaluated. β-carotene showed to be a great antibacterial natural compound against gram-positive and gram-negative bacteria such as Listeria monocytogenes, Staphylococcus aureus and Salmonella enterica with Minimal Inhibitory Concentration (MIC) of about 0.225, 0.1125, 0.225 µg/mL, respectively. Those findings are in favor of the exploitation of H. scoparia pigments in therapeutic fields as an antidiabetic source directly by the inhibition of α-amylase and trypsin as well as antibacterial agents against gastrointestinal infections. [ABSTRACT FROM AUTHOR]

Vesicles are one of the most important self‐assembled manifestations because of their multidimensional applications in biology, catalysis and adsorption. Several synthetic vesicles have been prepared from small peptides, amphiphilic fatty acids, amino acids and organic molecules etc. Transition metal complexes derived from different types of ligands are found to be self assembled to form solid state networks and also supramolecular aggregates in solution. In this review article we have discussed about synthesis, morphology and utility of vesicles formed by 14 transition metal complexes of some amphiphilic and non‐amphiphilic ligands. Interestingly, vesicles derived from transition metal complexes with non‐amphiphilic ligands are mostly soluble in organic solvents, whereas those derived from amphiphilic ligands are soluble in aqueous medium. As a result, their potential applications can be explored in complementary solvents accordingly. [ABSTRACT FROM AUTHOR]

To replace the hazardous organic solvents currently in use, one of the key objectives of green chemistry has been the development of green solvents obtained from natural sources. Natural deep eutectic solvents (NADES) are bio‐based natural compounds, namely primary metabolites like organic acids, sugar, alcohols, amines, and amino acids, which are acceptable to the environment and may eventually replace the conventionally used harsh organic solvents. This study focuses on the recent developments in the realm of these innovative materials as well as the conventional deep eutectic solvents (DES)‐based techniques. A more in‐depth examination of DES's applications in various chemical processes is covered after a description of its definition, manufacture, and unique characteristics. Their significance as designer solvents in various organic reactions and their impact on production methods are addressed. [ABSTRACT FROM AUTHOR]

The ascribed work suggests a fabrication pathway of carbon aerogel material from the rose apple (Syzygium jambos) fruit (RACA), in which a hydrothermal step, followed by a calcination process under various temperatures from 600 to 900 °C was carried out. RACA were characterized via multiple methods to briefly determine the optimal calcination temperature for the application, revealing that the temperature of 700 °C provided an intermediate deconstruction effect to form the amorphous structure and amplified the surface area. Whence, the materials were assessed for the adsorption capacities towards diesel oil which provided a capacity of approximately 35 g/g, although the adsorption capacity decreased slightly after 5 cycles of recovery and reuse. Furthermore, RACA‐700 exhibits high adsorption capacity of organic solvents (toluene, cyclohexane, butanol, hexane, and chloroform) and the ciprofloxacin antibiotic. Besides, the utilization of the fabricated carbon aerogel in the supercapacitor was also investigated. The obtained results elucidate the highest specific capacitance of 61.20 F/g, corresponding with the lowest resistance of 195.6 Ω, which indicates the ability to maintain capacitance after 5000 cycles and still retain 60 % efficiency, thereby signifying the potential application of carbon aerogel in sustainable material construction. [ABSTRACT FROM AUTHOR]

AbstractMost studies on the beneficial effects of polyphenols on human health have focused on polyphenols extracted using aqueous organic solvents, ignoring the fact that a portion of polyphenols form complexes with polysaccharides. Polysaccharides and polyphenols are interrelated, and their interactions affect the physicochemical property, quality, and nutritional value of foods. In this review, the distribution of bound polyphenols in major food sources is summarized. The effect of food processing on the interaction between polyphenols and cell wall polysaccharides (CWP) is discussed in detail. We also focus on the digestion, absorption, and metabolic behavior of polysaccharide-polyphenol complexes. Different food processing techniques affect the interaction between CWP and polyphenols by altering their structure, solubility, and strength of interactions. The interaction influences the free concentration and extractability of polyphenols in food and modulates their bioaccessibility in the gastrointestinal tract, leading to their major release in the colon. Metabolism of polyphenols by gut microbes significantly enhances the bioavailability of polyphenols. The metabolic pathway and product formation rate of polyphenols and the fermentation characteristics of polysaccharides are affected by the interaction. Furthermore, the interaction exhibits synergistic or antagonistic effects on the stability, solubility, antioxidant and functional activities of polyphenols. In summary, understanding the interactions between polysaccharides and polyphenols and their changes in food processing is of great significance for a comprehensive understanding of the health benefits of polyphenols and the optimization of food processing technology. [ABSTRACT FROM AUTHOR]

The use of deicers in urban areas, on runways and aircrafts has raised concerns about their environmental impact. Understanding the ice-melting mechanism is crucial for developing environmentally friendly deicers, yet it remains challenging. This study employs machine learning to investigate the ice penetration capacity (IPC) of 21 salts and 16 organic solvents as deicers. Relationships between their IPC and various physical properties were analysed using extreme gradient boosting (XGBoost) and Shapley additive explanation (SHAP). Three key ice-melting mechanisms were identified: (1) freezing-point depression, (2) interactions between deicers and H2O molecules and (3) infiltration of ions into ice crystals. SHAP analysis revealed different ice-melting factors and mechanisms for salts and organic solvents, suggesting a potential advantage in combining the two. A mixture of propylene glycol (PG) and sodium formate demonstrated superior environmental impact and IPC. The PG and sodium formate mixture exhibited higher IPC when compared to six commercially available deicers, offering promise for sustainable deicing applications. This study provides valuable insights into the ice-melting process and proposes an effective, environmentally friendly deicer that combines the strengths of organic solvents and salts, paving the way for more sustainable practices in deicing. [ABSTRACT FROM AUTHOR]

The field of supported catalysis has experienced increased attention with respect to the development of novel architectures for immobilizing catalytic species, aiming to maintain or enhance their activity while facilitating the easy recovery and reuse of the active moiety. Dendrimers have been identified as promising candidates capable of imparting such properties to catalysts through selective functionalization. The present study details the synthesis of two polyphosphorhydrazone (PPH) dendrons, each incorporating azide or acetylene groups at the core for subsequent coupling through "click" triazole chemistry. Employing this methodology, a novel PPH Janus dendrimer was successfully synthesized, featuring ten polyethylene glycol (PEG) chains on one side of the structure and ten Ru(p-cymene) derivatives on the other. This design was intended to confer dual properties, influencing solubility modulation, and allowing the presence of active catalytic moieties. The synthesized dendrimer underwent testing in the isomerization of allyl alcohols in organic solvents and biphasic solvent mixtures. The results demonstrated a positive dendritic effect compared with model monometallic and bimetallic species, providing a proof-ofconcept for the first PPH Janus dendrimer with tested applications in catalysis. [ABSTRACT FROM AUTHOR]

Extraction of compounds with different physicochemical properties from a complex matrix usually involves several individual steps and requires large volumes of organic solvents. In this pioneering study, we propose a comprehensive two-step supercritical fluid extraction using carbon dioxide, ethanol, and water. This novel approach allows the extraction of non-polar and polar analytes within one run in two consecutive steps. Indeed, the first step with a dominant amount of CO2 with only 2% cosolvent allowed the selective extraction of non-polar volatile terpenes only in 20 min. The conditions were then automatically switched. Increasing the cosolvent volume in the extraction solvent up to 44% (v/v) resulted in the extraction of more polar compounds, including flavonoids and phenolic acids, in 60 min. Importantly, switching the supercritical fluid extraction (SFE) conditions does not require any manual intervention but results in two separate fractions containing target compounds with distinctly different physicochemical properties. The novel method was verified in terms of repeatability, accuracy, precision, and greenness. Two-step SFE was applied to seven plant species differing in volatile terpenes and phenolic profiles. The results proved that this concept is suitable for the analysis of complex plant samples. In addition, it enables a reduction in the toxic solvents consumption, extraction time, and manual intervention required for traditional extraction approaches when isolating different groups of metabolites. [ABSTRACT FROM AUTHOR]

This study presents a novel environmentally friendly approach for synthesizing a water-compatible superhydrophilic molecularly imprinted resin on graphene oxide (SMIR/PGO). In the design of SMIR/PGO, dopamine (DA) serves a dual role: (1) self-polymerizing on the GO surface to form polydopamine, which acts as an environmentally friendly bridge for covalently grafting SMIR and (2) acting as green hydrophilic monomers, replacing traditional phenolic monomers to obtain SMIR. The dual role of DA eliminates the need for tedious steps such as separation, washing, and drying of intermediate materials, facilitating a simple one-pot synthesis. Additionally, hexamethylenetetramine (HMTA) replaces the traditional crosslinker formaldehyde, thereby avoiding direct contact with the carcinogenic formaldehyde. The NH3 produced by HMTA decomposition acts as a catalyst, obviating the need for additional catalysts in the synthesis of SMIR/PGO. This one-pot synthesis occurs in an aqueous matrix and entirely avoids the use of organic solvents, aligning with green chemistry principles and ensuring compatibility with aqueous solutions. Consequently, SMIR/PGO combines the high specific surface area of GO, the multifunctionality of polydopamine, and the excellent water compatibility and high selectivity of SMIR. This combination provides multiple adsorption interactions to achieve selective extraction of chlorogenic acid in the aqueous matrix. This environmentally friendly synthetic strategy offers an efficient means of designing superhydrophilic molecularly imprinted materials with exceptional recognition and adsorption capabilities in aqueous environments. [ABSTRACT FROM AUTHOR]

Thin-film selective layers fabricated via interfacial polymerization (IP) form the core of membrane-based water purification and desalination, as well as other molecular separations. The monomers and organic solvents used in the reaction are for the most part toxic chemicals, likely to be banned in the near future, for environmental protection. There is, therefore, a growing need to find alternative, sustainable, materials that can produce adequate membranes for industrial applications, fabricated via IP. The present work summarizes recent studies on fabricating RO/NF/OSN membranes via IP using sustainable solvents and/ or monomers, in comparison to the toxic chemicals used to fabricate polyamide, the chosen polymeric material for the commercial selective membrane layer. The properties of these ‘green’ materials are described, as well as the properties of the resultant membranes, discussing possible limitations in the fabrication techniques and the benefits of the process. Furthermore, an eco-scale score is calculated for representative membranes, demonstrating the utility of this tool for assessing the ‘greenness’ of the fabricated membranes. Overall, the presented literature shows that there is a great potential for fabricating more sustainable and scalable membranes. However, studies exhibit various limitations, for example, no standardization for performance tests and performance criteria for every membrane type, which prevents accurate and true comparisons among different membranes. Suggestions are made, where applicable, for future work to add aspects that assess the potential of fabricated membranes to future industrial applications. Finally, and most importantly, there is still a need for improved fundamental understanding of IP, with which to facilitate the search of alternative sustainable materials for membrane fabrication with desired properties. [ABSTRACT FROM AUTHOR]

Lipases are important biocatalysts and ubiquitous in plants, animals, and microorganisms. The high growth rates of microorganisms with low production costs have enabled the wide application of microbial lipases in detergent, food, and cosmetic industries. Herein, a novel lipase from Lacticaseibacillus rhamnosus IDCC 3201 (Lac-Rh) was isolated and its activity analyzed under a range of reaction conditions to evaluate its potential industrial application. The isolated Lac-Rh showed a molecular weight of 24 kDa and a maximum activity of 3438.5 ± 1.8 U/mg protein at 60 °C and pH 8. Additionally, Lac-Rh retained activity in alkaline conditions and in 10% v/v concentrations of organic solvents, including glycerol and acetone. Interestingly, after pre-incubation in the presence of multiple commercial detergents, Lac-Rh maintained over 80% of its activity and the stains from cotton were successfully removed under a simulated laundry setting. Overall, the purified lipase from L. rhamnosus IDCC 3201 has potential for use as a detergent in industrial applications. Key points: • A novel lipase (Lac-Rh) was isolated from Lacticaseibacillus rhamnosus IDCC 3201 • Purified Lac-Rh exhibited its highest activity at a temperature of 60 °C and a pH of 8, respectively • Lac-Rh remains stable in commercial laundry detergent and enhances washing performance [ABSTRACT FROM AUTHOR]

The article explores the use of the enzyme PestE from Pyrobaculum calidifontis VA1 for the enzymatic synthesis of hydroxycinnamic acid amides (HCAAs). HCAAs are natural compounds with potential applications in various industries. The current methods for synthesizing HCAAs are not environmentally friendly, so enzymatic methods are being explored as a greener alternative. The study focuses on the synthesis of N-trans-feruloyltyramine using PestE and found that the reaction was most efficient at 60 °C with a specific molar ratio. The use of acetonitrile as a cosolvent posed challenges, but ascorbic acid could be added to prevent substrate oxidation. PestE was also found to catalyze the formation of other hydroxycinnamic acid amides. Overall, this enzymatic method offers a more sustainable approach to HCAA synthesis. [Extracted from the article]

Enzymes have gained their unique efficiency and catalytic activity through billions of years of evolution, perfecting their active site to a desired reaction. Inspired by nature, a novel enzyme‐mimicking platform is designed based on stable protein 1 (SP1) to create a nano‐compartment that mimics peroxidase activity. The biohybrid reveals enhanced activity over the hemin cofactor alone and improved stability in organic solvents in comparison to native peroxidase. Furthermore, the utilization of the obtained biohybrid in an optical glucose biosensing platform is shown. The biohybrid crystallographic structure is solved, indicating that the SP1 structure is not affected by the hemin coordination. This work opens the path for developing new cofactor binding centers in engineered protein scaffolds for various artificial catalytic processes. [ABSTRACT FROM AUTHOR]

The article describes a green and efficient synthesis method for pyrano[2,3-c]-pyrazoles, employing DL-alpha-tocopherol methoxypolyethylene glycol succinate solution (TPGS-750-M) as a green and biodegradable surfactant in water. The utilization of water as a reaction medium and TPGS-750-M as a surfactant obviates the necessity for organic solvents, thereby enhancing the environmental sustainability of the synthesis. The compounds synthesized using this novel method was characterized using various spectroscopic techniques, including 1H-NMR, 13C-NMR, and mass spectrometry. [ABSTRACT FROM AUTHOR]

The present study aims at understanding the effect of organic solvents on the specific proteolytic activity and operational stability of asclepain cI in aqueous-organic media, using correlations between geometrical and structural parameters of asclepain cI. These correlations were determined by molecular dynamics (MD) simulations and the secondary structure of the enzyme validated by Fourier-transform Infrared (FTIR) spectroscopy. Asclepain cI exhibited significantly higher catalytic potential in 29 of the 42 aqueous-organic media tested, composed by 0.1 mM TRIS hydrochloride buffer pH 8 (TCB) and an organic solvent, than in buffer alone. Asclepain cI in water-organic miscible systems showed high FTIR spectral similarity with that obtained in TCB, while in immiscible systems the enzyme acquired different secondary structures than in buffer. Among the conditions studied, asclepain cI showed the highest catalytic potential in 50% v/v ethyl acetate in TCB. According to MD simulations, that medium elicited solvation and flexibility changes around the active center of asclepain cI and conducted to a new secondary structure with the active center preserved. These results provide valuable insights into the elucidation of the molecular mechanism of asclepain cI tolerance to organic solvents and pave the way for its future application for the synthesis of peptides in aqueous-organic media. [ABSTRACT FROM AUTHOR]