Pure Compounds Research Articles

Protective Effects of Tunisian Orange Co-Product Extract and Oleuropein-Hesperidin Combination on Bleomycin-Induced Pulmonary Fibrosis in Rats.

Idiopathic pulmonary fibrosis (IPF) is a chronic interstitial pneumonia that leads to acute lung damage, deterioration of lung function, and increased mortality risk. In this study, we investigated the effects of the orange coproduct extract (OCE) and the combination of pure hesperidin and oleuropein (HO) on an experimental model of pulmonary fibrosis induced by bleomycin (BLM) in Wistar rats. Rats were divided into six groups: the control group (G1), the BLM group (G2), three groups (G3, G4, G5) receiving a single dose of BLM combined with OCE extract at 100, 200, and 300 mg/kg, and group 6 (G6) receiving a single dose of BLM combined with HO: both pure major phenolic compounds of OCE (hesperidin at 50 mg/kg) and olive leaves (oleuropein at 2.5 mg/kg). Oxidative stress in lung tissues was investigated using catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPX) assays and the measurement of malondialdehyde (MDA) and lactate dehydrogenase (LDH) levels. Treatment with OCE and HO normalized the disturbance in oxidative markers' levels and showed a significant reduction in fibrosis score with no renal or hepatic toxic effects. In conclusion, OCE and HO exhibit antifibrotic effects on a rat model of pulmonary fibrosis.

Application of volume‐translated rescaled perturbed‐chain statistical associating fluid theory equation of state to pure compounds using an expansive experimental database

AbstractThe performance of the perturbed‐chain statistical associating fluid theory‐type equations of state (PC‐SAFT‐type EOSs) is compromised in predicting properties of pure compounds in the critical region. In our previous research, we introduced an improved volume‐translated rescaled PC‐SAFT EOS (VTR‐PC‐SAFT EOS) by incorporating a dimensionless distance‐function. Such VTR‐PC‐SAFT EOS is built based on a critical point‐based PC‐SAFT EOS that can reproduce the critical temperature, critical pressure, and critical molar volume of pure compounds. VTR‐PC‐SAFT EOS is found to significantly improve the accuracy of phase behavior predictions in both critical and noncritical regions for pure compounds. In this study, we assess the performance of VTR‐PC‐SAFT EOS in reproducing the critical and noncritical properties of 251 pure compounds, encompassing 20 distinct chemical species. The testing results indicate that, compared to the other three PC‐SAFT‐type EOSs, the VTR‐PC‐SAFT EOS can consistently provide more accurate representations of critical and noncritical properties of 251 pure compounds.

Gold‐Zinc Co‐Catalyzed Alkynoate Hydrocarboxylation with N‐Protected Amino Acids for Preparation of Storable Acylating Reagents and Racemization‐Free Peptide Synthesis

AbstractHydrocarboxylation of methyl 2‐octynoate, a chemical commercially available at a low cost, with N‐protected amino acids was developed with a gold‐zinc cooperative catalyst constructed with a 5‐[(2,2′‐bipyridin)‐5‐yl]imidazo[1,5‐a]pyridin‐3‐ylidene to prepare α‐methoxycarbonyl enol esters as acylating reagents. The α‐methoxycarbonyl enol esters were isolable through silica‐gel column chromatography and storable without precautions regarding moisture. Acylation of free amines with the α‐methoxycarbonyl enol esters proceeded without epimerization of the stereogenic center derived from the enol esters, affording analytically pure dipeptide compounds through filtration and hexane‐washing.

Knudsen effusion mass spectrometry: Current and future approaches.

Knudsen effusion mass spectrometry (KEMS) has been a powerful tool in physical chemistry since 1954. There are many excellent reviews of the basic principles of KEMS in the literature. In this review, we focus on the current status and potential growth areas for this instrumental technique. We discuss (1) instrumentation, (2) measurement techniques, and (3) selected novel applications of the technique. Improved heating methods and temperature measurement allow for better control of the Knudsen cell effusive source. Accurate computer models of the effusive beam and its introduction to the ionizer allow optimization of such parameters as sensitivity and removal of background signals. Computer models of the ionizer allow for optimized sensitivity and resolution. Additionally, data acquisition systems specifically tailored to a KEMS system permit improved quantity and quality of data. KEMS is traditionally utilized for thermodynamic measurements of pure compounds and solutions. These measurements can now be strengthened using first principles and model-based computational thermochemistry. First principles can be used to calculate accurate Gibbs energy functions (gefs) for improving third law calculations. Calculated enthalpies of formation and dissociation energies from ab initio methods can be compared to those measured using KEMS. For model-based thermochemistry, solution parameters can be derived from measured thermochemical data on metallic and nonmetallic solutions. Beyond thermodynamic measurements, KEMS has been used for many specific applications. We select examples for discussion: measurements of phase changes, measurement/control of low-oxygen potential systems, thermochemistry of ultrahigh-temperature ceramics, geological applications, nuclear applications, applications to organic and organometallic compounds, and thermochemistry of functional room temperature materials, such as lithium ion batteries. We present an overview of the current status of KEMS and discuss ideas for improving KEMS instrumentation and measurements. We discuss selected KEMS studies to illustrate future directions of KEMS.

Exploring of Be1-xCrxSe alloys for spintronics and optoelectronic applications

In this study, spin polarized density functional theory (DFT) is implemented to predict physical characteristic of Be1-xCrxSe (x = 6.25%, 12.5%, 18.75%, 25%) compound. The electronic characteristics of pure BeSe compound show semiconductor behavior but after Cr doping BeSe elucidate half-metallic ferromagnetism (HMF) for all doping concentrations. The outcomes elucidate the total magnetic moment MTot per Cr-atom are 4.0028, 4.0027, 4.0021 and 4.0002 μB for 6.25%, 12.5%, 18.75%, 25% concentrations, respectively and the magnetism mainly originated from d-state of the impurity atom which is further ensured from the magnetic spin density. Furthermore, the optical parameters are also computed to determine the effect of doping on the material’s response to incident light of energy spanning from 0 to 10 eV. The optical study depict that the studied systems possess maximum absorbance and optical conductivity in UV-range with minimal reflection. The overall outcomes illustrate that the Cr doped beryllium selenide (BeSe) is promising material for spintronic and optoelectronic devices.

Cytoprotection of Cecropia obtusifolia Bertol (Cecropiaceae) extract on the normal adherent cell line of human fibroblasts Hs68

The study focuses on the therapeutic action of medicinal plants used in the treatment of chronic degenerative diseases. The ethanolic extract of the Mexican species Cecropia obtusifolia Bertol, traditionally used for diabetes, was evaluated. The cytoprotective effect was determined on the normal adherent human fibroblast cell line Hs68, and its toxicity was assessed on Artemia salina. The cytoprotective effect was determined using the neutral red (NR) assay, demonstrating a viability of 98 %, indicating a very low cytotoxic effect and no toxicity on A. salina. These assays have been routinely employed as screening methods for natural extracts and pure compounds with potential therapeutic effects against cancer

A multi-instrumental approach for calibrating real-time mass spectrometers using high-performance liquid chromatography and positive matrix factorization

Abstract. Obtaining quantitative information for molecular species present in aerosols from real-time mass spectrometers such as an extractive electrospray time-of-flight mass spectrometer (EESI) and an aerosol mass spectrometer (AMS) can be challenging. Typically, molecular species are calibrated directly through the use of pure standards. However, in some cases (e.g., secondary organic aerosol (SOA) formed from volatile organic compounds (VOCs)), direct calibrations are impossible, as many SOA species can either not be purchased as pure standards or have ambiguous molecular identities. In some cases, bulk OA sensitivities are used to estimate molecular sensitivities. This approach is not sufficient for EESI, which measures molecular components of OA, because different species can have sensitivities that vary by a factor of more than 30. Here, we introduce a method to obtain EESI calibration factors when standards are not available, and we provide a thorough analysis of the feasibility, performance, and limitations of this new technique. In this method, complex aerosol mixtures were separated with high-performance liquid chromatography (HPLC) followed by aerosol formation via atomization. The separated aerosols were then measured by an EESI and an AMS, which allowed us to obtain sensitivities for some species present in standard and SOA mixtures. Pure compounds were used to test the method and characterize its uncertainties, and obtained sensitivities were consistent within ±20 % when comparing direct calibrations vs. HPLC calibrations for a pure standard and within a factor of 2 for a standard mixture. In some cases, species were not completely resolved by chromatography, and positive matrix factorization (PMF) of AMS data enabled further separation. This method should be applicable to other real-time MS techniques. Improvements in chromatography are possible that would allow better separation in complex mixtures.

Pseudomonas synxantha volatile organic compounds: efficacy against Cadophora luteo-olivacea and Botrytis cinerea of kiwifruit.

Volatile organic compounds (VOCs) are responsible for the antagonistic activity exerted by different biological control agents (BCAs). In this study, VOCs produced by Pseudomonas synxantha strain 117-2b were tested against two kiwifruit fungal postharvest pathogens: Cadophora luteo-olivacea and Botrytis cinerea, through in vitro and in vivo assays. In vitro results demonstrated that P. synxantha 117-2b VOCs inhibit mycelial growth of C. luteo-olivacea and B. cinerea by 56% and 42.8% after 14 and 5 days of exposition, respectively. In vivo assay demonstrated significant inhibitory effects. VOCs used as a biofumigant treatment reduced skin-pitting symptoms disease severity by 28.5% and gray mold incidence by 66.6%, with respect to the untreated control. BCA volatiles were analyzed by solid-phase microextraction coupled with gas chromatography-mass spectrometry (SPME-GC/MS), and among the detected compounds, 1-butanol, 3-methyl and 1-nonene resulted as the most produced. Their efficacy as pure synthetic compounds was assayed against mycelial growth of fungal pathogens by different concentrations (0.34, 0.56, and 1.12 µL mL-1 headspace). The effect of the application of VOCs as a biofumigant was also investigated as the expression level of seven defense-related genes of kiwifruit at different exposition times. The results indicated an enhancement of the expression of almost all the genes starting from 3h of treatment. These results described P. synxantha VOCs characteristics and their potential as a promising method to adopt for protecting kiwifruit from postharvest diseases caused by C. luteo-olivacea and B. cinerea.

Advanced high-resolution chromatographic strategies for efficient isolation of natural products from complex biological matrices: from metabolite profiling to pure chemical entities

AbstractThe isolation of pure compounds from extracts represents a key step common to all investigations of natural product (NP) research. Isolation methods have gone through a remarkable evolution. Current approaches combine powerful metabolite profiling methods for compounds annotation with omics mining results and/or bioassay for bioactive NPs/biomarkers priorisation. Targeted isolation of prioritized NPs is performed using high-resolution chromatographic methods that closely match those used for analytical profiling. Considerable progress has been made by the introduction of innovative stationary phases providing remarkable selectivity for efficient NPs isolation. Today, efficient separation conditions determined at the analytical scale using high- or ultra-high-performance liquid chromatography can be optimized via HPLC modelling software and efficiently transferred to the semi-preparative scale by chromatographic calculation. This ensures similar selectivity at both the analytical and preparative scales and provides a precise separation prediction. High-resolution conditions at the preparative scale can notably be granted using optimized sample preparation and dry load sample introduction. Monitoring by ultraviolet, mass spectrometry, and or universal systems such as evaporative light scattering detectors and nuclear magnetic resonance allows to precisely guide the isolation or trigger the collection of specific NPs with different structural scaffolds. Such approaches can be applied at different scales depending on the amounts of NPs to be isolated. This review will showcase recent research to highlight both the potential and constraints of using these cutting-edge technologies for the isolation of plant and microorganism metabolites. Several strategies involving their application will be examined and critically discussed. Graphical abstract

Metal-enzyme nanogel biochemical composite: An efficient platform for one-pot dynamic kinetic resolution of amines

One-pot dynamic kinetic resolution (DKR) has garnered considerable attention for its potential to generate enantiomerically pure compounds in high yields and simplifying operation. However, the challenge lies in achieving compatibility between enzymes and metals due to their distinct operating conditions. In this study, we present a novel cascade catalytic platform for the DKR of amines to address this issue. Pd nanoparticles were immobilized on lysine-decorated lipase nanogels, forming isolated metal-enzyme catalysts. The microwave-assisted one-pot DKR of amines was carried out under non-pressurized conditions at 50 °C for 5 h. The metal-enzyme nanogel biochemical composite exhibited excellent performances, with a high conversion rate of 98% and enantiomeric excess values exceeding 99%. This innovative approach demonstrates the potential of constructing a multifunctional metalloenzyme catalytic platform with a distinctive three-dimensional structure, which offers promising prospects for DKR applications.

Exploring the gas sensing potential of BiOBr0.9I0.1: A highly responsive sensor for ammonia detection at room temperature

Bismuth halide oxides (BiOX, where X = Cl, Br, I) are renowned in photocatalysis for their distinct layered structure, modifiable band gap, and affordability. However, their application in gas sensing has garnered comparatively less research attention. Notably, solid solutions of BiOX demonstrate superior attributes over pure BiOX compounds. BiOBrxI1-x solid solution was successfully synthesized using in situ precipitation method and used as a gas-sensitive material for ammonia (NH3) gas sensor. The structural and compositional integrity of the synthesized samples was meticulously confirmed by X-ray diffraction (XRD), which revealed the coexistence of different BiOBr and BiOI phases. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) provided insights into the morphology, revealing a flower-like nanostructure, which favors the surface reaction rate. The electronic and optical properties of the material were further elucidated by photoluminescence (PL) spectroscopy and ultraviolet–visible diffuse reflectance spectroscopy (UV-DRS), which revealed that the band gap is tailored to facilitate the sensitivity and selectivity of ammonia detection. Key properties including surface area and porosity were quantitatively evaluated by Bruner-Emmett-Taylor (BET) analysis and found BiOBr0.9I0.1 sensor to have a specific surface area of 13.08 m2/g. Specifically, the BiOBr0.9I0.1 sensor's response ratio (Ra/Rg) to 100 ppm of ammonia reaches 8, approximately fourfold higher than that of the pure BiOBr sensor. The flower-like morphology of BiOBr0.9I0.1 enhances surface activity and charge transfer efficiency, thereby facilitating greater gas adsorption and elevating sensor performance. The rapid response and recovery times (12/24 s at 30 ppm), low detection threshold (LOD, 0.75 ppm), along with its selectivity and reproducibility at room temperature, position the BiOBr0.9I0.1 material as a promising candidate for ammonia gas detection.

Thermoelectric, mechanical and electrochemical properties of pure single-phase FeSb

This study primarily focused on forming pure single-phase FeSb and explored its thermoelectric, mechanical, and electrochemical properties since no reports are available. The FeSb binary alloy has been synthesized through the vacuum melting method, and the phase formation has been confirmed through powder X-ray diffraction (PXRD). The PXRD results show that the synthesized FeSb binary alloy belongs to the hexagonal crystal structure with space group P63/mmc, which coincides with ICSD no. 53971. The pure single phase has been formed by creating a deficiency of 10 % in antimony. The High-Resolution Scanning Electron Microscopy (HR-SEM) and Energy Dispersive X-ray (EDX) analysis have been used to identify the pure single-phase and various elemental components of the hot-pressed pellet of FeSb0.9. The atomic wt.% of iron (Fe) and antimony (Sb) have been identified through EDX spectral analysis. The highest Seebeck coefficient value of −5.4 μV/K is achieved at 497 K, and the lowest electrical conductivity value of 24049 S/m is achieved at 447 K. The hardness of the material is found to be 6.076 GPa, which is much more sufficient for thermoelectric material during industrial handling. The magnetic characteristics of the prepared pure phase FeSb compound have also been measured by Vibrating Scanning Magnetometer (VSM) analysis, which has a weak ferromagnetic nature. Furthermore, three electrodes were employed to study the electrochemical properties, and the alloy has attained the appreciable specific capacitance of 169.5 F/g at 2 A/g.

Isolation of a novel quercetin derivative from Terminalia chebula and RT-PCR-assisted probing to investigate its DNA repair in hepatoma cells.

DNA damage can lead to carcinogenesis if replication proceeds without proper repair. This study focused on the purification of a novel quercetin derivative present in Terminalia chebula fruit and studied its protective role in hepatoma cells due to H2O2-DNA damage. The pure compound obtained from the silica gel column was subjected to structural characterization using spectroscopic techniques. MTT assay was employed to select a non-toxic concentration of the isolated compounds on HepG2 and Chang liver cells. The antigenotoxic property of the compound on HepG2 and Chang liver cells was carried out by alkaline comet assay. Analyses of expression levels of mRNA for two DNA repair enzymes, OGG1 and NEIL1, in HepG2 and Chang liver cells, were carried out using the RT-PCR method. The pure compound obtained from the fraction-5 of diethyl ether extract was identified as a novel quercetin derivative and named 7-(but-2-en-1-yloxy)-2-(4(but-2-en-1-yloxy)-3-hydroxyphenyl)-3- (hexa-2,4-dien-1-yloxy)-6-hydroxy-4H-chromen-4-one. This compound recorded modest toxicity at the highest concentration tested (percentage cell viability at 100 μg/mL was 64.71 ± 0.38 for HepG2 and 45.32 ± 0.07 for Chang liver cells). The compound has demonstrated noteworthy protection against H2O2-induced DNA damage in both cell lines. Analyses of mRNA expression levels for enzymes OGGI and NEIL1 enzymes in HepG2 and Chang liver cells asserted the protective role of the isolated compound against H2O2-induced DNA damage. The protective effect of a novel quercetin derivative isolated from T. chebula in the hepatoma cells is reported here for the first time.

Cubic-two-state equation of state for modeling liquid-liquid and vapor-liquid equilibria of nitriles + hydrocarbons or water mixtures

The cubic-two-state (CTS) equation of state (EoS) was employed for modeling the liquid-liquid and vapor-liquid equilibria of nitriles + hydrocarbons (alkanes and aromatics) or water mixtures. For nitriles, the five pure compound parameters were determined by fitting the model simultaneously to experimental saturation pressure, density of saturated liquid, enthalpy of vaporization and liquid-liquid equilibrium data when mixed with n-dodecane. For alkanes, the pure parameters were those determined from conventional corresponding states correlations for Soave-Redlich-Kwong EoS. The van der Waals mixing and combining rules were applied for dispersive parameter and covolume, with a temperature-dependent binary parameter. In the case of nitrile mixtures with aromatics and water, cross-association were considered with the previously published CTS combining rules, and no association binary parameters were required. The correlations were very good in all cases. The model was also able to predict selective extraction of sulfur compounds (benzothyophene and benzothyophene 1,1-oxide) from alkanes. Because of its simplicity, therefore, the CTS EoS is a very attractive option for process simulation involving this class of mixtures.

Role of cyclodextrin inclusion complexes assembled in the fast-dissolving structures of electrospun gelatin mats to extend the release of menthol

In this study, inclusion complexes (ICs) of menthol with various cyclodextrins (CDs) [α-CD, β-CD, γ-CD, (2-hydroxypropyl)-β-cyclodextrin (HP-β-CD), and methyl-β-cyclodextrin (M-β-CD)] were prepared, and the ICs with the highest encapsulation efficiency were applied in the electrospun gelatin mats to extend the release of menthol. Electrospinning feed solutions were evaluated based on surface tension, zeta potential, electrical conductivity, and rheological properties. The diameter and morphology of the pure gelatin and the CDs-loaded gelatin mats were analyzed using microscopy (FESEM and AFM). The results confirmed that CD loading leads to a decrease in the diameter of the nanofibers. The longest disintegration time belonged to the gelatin mat containing the β-CD complex. Comparison of the FTIR spectrum and XRD patterns of gelatin mats containing menthol-loaded CD complexes with the pure compounds confirmed the successful encapsulation of menthol inside the cavity of the CD, and the disappearance of the crystalline state of electrospun gelatin mats. Applying the electrospun gelatin mats as a fast-dissolving structure for the menthol-loaded inclusion complexes increased its thermal stability. In the bioadhesive test, the lowest force required to separate the gelatin mat from the skin model was obtained in the menthol-containing β-CD gelatin mat (6.21 ± 1.01 g). The menthol release from the pure gelatin mats was much faster than the electrospun mats containing CD complexes. Peppas-Sahlin and Fickian diffusion (Case-I) were the best-fitted model and menthol release mechanism, respectively.

Asymmetric Synthesis of Dihydropyrimidinethione Podand in the Presence of C2‐Symmetric Bis(Hydroxy)Proline‐Containing Amides

AbstractA stereoselective Biginelli reaction involving a CH‐active podand, thiourea, and benzaldehyde was carried out using C2‐symmetric bis(hydroxy)proline‐containing amides as chiral inducers. The target dihydropyrimidinethione‐containing podand was obtained with an enantiomeric excess of 65–75 % and a yield of 58 % under mild conditions. It was established that in the process of asymmetric induction the value of ee depended on the presence of OH group in the proline fragment and of the linker structure in the chiral inducer molecule, in particular, on the presence of asymmetric carbon atoms and the movability of the single bond between them in the linker itself. Based on experimental data, one of the probable reaction mechanisms confirming the special role of the L‐proline or trans‐4‐hydroxyproline fragments in asymmetric induction has been proposed. The developed technique for obtaining an active tuberculostatic agent expands the possibilities for using C2‐symmetric chiral inducers in asymmetric catalysis and is of interest for the synthesis of enantiomerically pure compounds of similar structure.

Unraveling order and entropy with modern quasi-chemical models

In this work, the derivation of a general expression for the residual entropy for quasi-chemical models – including modern COSMO-RS/SAC – is shown. This expression is equivalent to equations that had to be assumed or postulated in previous works. More interestingly, it allows to unravel order (or non-randomness) in pure compounds and mixtures in a very detailed way. It is possible to investigate the entropic contribution of every possible pair of molecular surface segments, without relying on any lattice or coordination number. Different types of mixtures are very well explained by modern quasi-chemical models, including polar, apolar, and associating compounds showing positive, negative, and s-shaped excess entropy. Finally, it is shown that these models are unable to precisely represent some aqueous mixtures — the assumption of pairwise additive interactions is apparently too limited in those cases.

Comparative analysis of whole plant, flower and root extracts of Chamomilla recutita L. and characteristic pure compounds reveals differential anti-inflammatory effects on human T cells.

Chronic inflammation is a hallmark of chronic wounds and inflammatory skin diseases. Due to a hyperactive and prolonged inflammation triggered by proinflammatory immune cells, transitioning to the repair and healing phase is halted. T cells may exacerbate the proinflammatory milieu by secreting proinflammatory cytokines. Chamomilla recutita L. (chamomile) has been suggested for use in several inflammatory diseases, implying a capability to modulate T cells. Here, we have characterized and compared the effects of differently prepared chamomile extracts and characteristic pure compounds on the T cell redox milieu as well as on the migration, activation, proliferation, and cytokine production of primary human T cells. Phytochemical analysis of the extracts was carried out by LC-MS/MS. Primary human T cells from peripheral blood (PBTs) were pretreated with aqueous or hydroethanolic chamomile extracts or pure compounds. Subsequently, the effects on intracellular ROS levels, SDF-1α induced T cell migration, T cell activation, proliferation, and cytokine production after TCR/CD3 and CD28 costimulation were determined. Gene expression profiling was performed using nCounter analysis, followed by ingenuity pathway analysis, and validation at protein levels. The tested chamomile extracts and pure compounds differentially affected intracellular ROS levels, migration, and activation of T cells. Three out of five differently prepared extracts and two out of three pure compounds diminished T cell proliferation. In line with these findings, LC-MS/MS analysis revealed high heterogeneity of phytochemicals among the different extracts. nCounter based gene expression profiling identified several genes related to T cell functions associated with activation and differentiation to be downregulated. Most prominently, apigenin significantly reduced granzyme B induction and cytotoxic T cell activity. Our results demonstrate an anti-inflammatory effect of chamomile- derived products on primary human T cells. These findings provide molecular explanations for the observed anti-inflammatory action of chamomile and imply a broader use of chamomile extracts in T cell driven chronic inflammatory diseases such as chronic wounds and inflammatory skin diseases. Importantly, the mode of extract preparation needs to be considered as the resulting different phytochemicals can result in differential effects on T cells.

Tris(2-hydroxyethyl)ammonium-Based Protic "Ionic Liquids": Synthesis and Characterization.

The proton transfer associated with the synthesis of protic ionic liquids (PILs) is often incomplete, meaning that the parent compounds may coexist with the ionic species. However, PILs are proposed for many applications as pure compounds without analysis of their ionicity. This work focuses on tris(2-hydroxyethyl)ammonium-based PILs with lactate, hydrogen succinate, hydrogen malate, and dihydrogen citrate anions. The interest of these anions lies in their low toxicity and capacity to disrupt the hydrogen-bonding network inherent to biopolymers. To improve current synthesis methods of this kind of PILs, which frequently lead to impurities derived from decomposition of reactants, working in the absence of solvents and at moderate temperatures is proposed. Through NMR studies, the ionicity of these systems was found to be low, from 20% to 86%, so the widely used term "ionic liquid" is not rigorous and must be used with caution. The un-ionized acid and base species coexist with the corresponding ionic forms, and this has to be considered in the studies involving these chemicals. The thermal characterization of the PILs was carried out. The influence of the anion on the thermal stability was found to be low. Isothermal thermogravimetric analysis showed that mass loss of these PILs starts at temperatures close to 350 K.

A new anti-inflammatory lupane in Ziziphus jujuba (L.) Gaertn. var. hysudrica Edgew.

ObjectivesTo investigate extracts of the stem bark of Ziziphus jujuba (L.) Gaertn. var. hysudrica Edgew. (Rhamnaceae) for anti-inflammatory activity and isolate the active principle(s). MethodsThe dry powder was macerated separately in three types of solvents to prepare methanol extract (ME), ethyl acetate extract (EE), and chloroform extract (CE). Following in vitro anti-inflammatory screening, the most active extract was selected to isolate the active compound. Both, the active extract and isolated compound were further tested on rats using the carrageenan-induced inflammation model. The blood and paw tissue were subjected to qPCR, and histopathology, respectively. Key findingsCE showed comparatively higher anti-inflammatory activity (85.0–95.0 %) in all in vitro assays, except the heat-induced membrane stabilization model (p < 0.05), and upon column chromatography, it yielded a pure crystalline compound. The compound was a pentacyclic triterpenoid (Lupane), named as hydroxymethyl (3β)-3-methyl-lup-20(29)-en-28-oate (Hussainate). CE (500 mg/kg) and Hussainate (1.0 mg/kg) reduced edema in 5 h after carrageenan administration. The activity of Hussainate was found to be comparable to that of dexamethasone (standard). The possible activity mechanism was the downregulation of tumor necrosis factor-alpha (TNF-α), cyclooxygenase-2 (COX-II), NF-κB, and IL-1β. ConclusionsThis study reveals that chloroform extract of the stem's bark of Z. jujuba may be used to prepare standardized anti-inflammatory herbal products using Hussainate as an active analytical marker. Hussainate may be used as a lead to develop anti-inflammatory drugs.