Pure Compounds Research Articles

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.

Antiproliferative, antioxidant and phytochemical analysis of Loranthus europaeus fruits

AbstractLoranthus europaeus with numerous therapeutic usages was chosen for further bioactivity assays and phytochemical analysis. The air‐dried grounded L. europaeus fruits were solvent extracted via Soxhlet apparatus. Afterwards, methanol extract was fractionated via different chromatographic methods and structures of the isolated pure compounds were elucidated with relative nuclear magnetic resonance spectra. Additionally, L. europaeus fruits essential oil was achieved through hydrodistillation and analyzed via gas chromatography‐mass spectrometry. Besides, the in vitro DPPH and nitric oxide antioxidant property of L. europaeus methanol extract alongside its phenolic and flavonoids content were evaluated. MTT (3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide) assay was carried out in A549 cancer cells and normal HUVECs cells for evaluating cytotoxicity of the plant extract and essential oil. Structure of the isolated major compounds of the extract were determined as two flavonoids. Analysis of the L. europaeus essential oil showed that it principally contained germacrene D (32.8%), β‐caryophyllene (19.2%) and alloaromadendrene (11.0%). In the MTT assay, 300 µg/mL of methanol extract caused ≈60% A549 cells death after 48 h with IC50 of 226 µg/mL. Likewise, the IC50 of the essential oil against A‐549 cell line for the 100 µg/mL L. europaeus fruits in 48 h was equal to 69 µg/mL. Overall, the present study is the first report on the phytochemical analysis of L. europaeus revealing occurrence of rhamnocitrin‐3‐O‐rhamnoside and rhamnetin‐3‐O‐rhamnoside in the plant extract alongside its high content of sesquiterpenoids in its essential oil. The observed antiproliferative activity of L. europaeus methanol extract against A549 cancer cells rather than healthy cells indicated its anti‐tumor properties which might be related to the high values of phenolic and flavonoids content in the methanol extract of the plant associated with its superior in vitro antioxidant activities.

The Isolation and Characterization of Antimicrobial Compounds Extracted from Rhus typhina.

Rhus typhina, a plant native to eastern North America, has previously been discovered to exhibit antibacterial activity against various ESKAPE pathogens including Staphylococcus aureus and Acinetobacter baumannii. The purpose of this work is to separate and purify compounds from the crude extracts using column chromatography, identify the pure compounds using NMR, and examine the therapeutic potential of these compounds on A.baumannii and S.aureus. A.baumannii is a non-motile, gram-negative, pleomorphic opportunistic pathogen and S.aureus is a non-motile, gram-positive, coccus-shaped, opportunistic pathogen; Both bacteria are major causes of nosocomial infections due to their ability to resist multiple antibiotics. As multi-drug resistance becomes more prevalent, there is a growing demand for research on new therapeutic agents. Supporting previous unpublished research from our laboratory, the data here suggest that ethanolic extracts of R.typhina contain compounds that exhibit antibacterial capabilities against both S. aureus and A. baumannii. Ongoing studies are focusing on determining the structure of the antimicrobial chemicals and the mode of action of these compounds.

Wondrous Yellow Molecule: Are Hydrogels a Successful Strategy to Overcome the Limitations of Curcumin?

Curcumin is a natural compound with a great pharmaceutical potential that involves anticancer, anti-inflammatory, antioxidant, and neuroprotective activity. Unfortunately, its low bioavailability, instability, and poor water solubility significantly deteriorate its clinical use. Many attempts have been made to overcome this issue, and encapsulating curcumin in a hydrogel matrix may improve those properties. Hydrogel formulation is used in many drug delivery forms, including classic types and novel forms such as self-assembly systems or responsive to external factors. Reviewed studies confirmed better properties of hydrogel-stabilized curcumin in comparison to pure compound. The main enhanced characteristics were chemical stability, bioavailability, and water solubility, which enabled these systems to be tested for various diseases. These formulations were evaluated for wound healing properties, effectiveness in treating skin diseases, and anticancer and regenerative activity. Hydrogel formulation significantly improved biopharmaceutical properties, opening the opportunity to finally see curcumin as a clinically approved substance and unravel its therapeutic potential.

Exploring nature's antidote: unveiling the inhibitory potential of selected medicinal plants from Kisumu, Kenya against venom from some snakes of medical significance in sub-Saharan Africa.

Background: The present study investigated the efficacy of Conyza bonariensis, Commiphora africana, Senna obtusifolia, Warburgia ugandensis, Vernonia glabra, and Zanthoxylum usambarense against Bitis arietans venom (BAV), Naja ashei venom (NAV), and Naja subfulva venom (NSV). Methods: 40 extracts and fractions were prepared using n-hexane, dichloromethane, ethyl acetate, and methanol. In vitro efficacy against snake venom phospholipase A2 (svPLA2) was determined in 96-well microtiter and agarose-egg yolk coagulation assays. in vivo efficacy against venom-induced cytotoxicity was determined using Artemia salina. Two commercial antivenoms were used for comparison. Results: The 96-well microtiter assay revealed poor svPLA2 inhibition of BAV by antivenom (range: 20.76% ± 13.29% to 51.29% ± 3.26%) but strong inhibition (>90%) by dichloromethane and hexane fractions of C. africana, hexane and ethyl acetate extracts and fraction of W. ugandensis, dichloromethane fraction of V. glabra, and the methanol extract of S. obtusifolia. The methanol extract and fraction of C. africana, and the hexane extract of Z. usambarense strongly inhibited (>90%) svPLA2 activity in NAV. The hexane and ethyl acetate fractions of V. glabra and the dichloromethane, ethyl acetate, and methanol extracts of C. africana strongly inhibited (>90%) svPLA2 in NSV. The agarose egg yolk coagulation assay showed significant inhibition of BAV by the dichloromethane fraction of C. africana (EC50 = 3.51 ± 2.58μg/mL), significant inhibition of NAV by the methanol fraction of C. africana (EC50 = 7.35 ± 1.800μg/mL), and significant inhibition of NSV by the hexane extract of V. glabra (EC50 = 7.94 ± 1.50μg/mL). All antivenoms were non-cytotoxic in A. salina but the methanol extract of C. africana and the hexane extracts of V. glabra and Z. usambarense were cytotoxic. The dichloromethane fraction of C. africana significantly neutralized BAV-induced cytotoxicity, the methanol fraction and extract of C. africana neutralized NAV-induced cytotoxicity, while the ethyl acetate extract of V. glabra significantly neutralized NSV-induced cytotoxicity. Glycosides, flavonoids, phenolics, and tannins were identified in the non-cytotoxic extracts/fractions. Conclusion: These findings validate the local use of C. africana and V. glabra in snakebite but not C. bonariensis, S. obtusifolia, W. ugandensis, and Z. usambarense. Further work is needed to isolate pure compounds from the effective plants and identify their mechanisms of action.

Aquatic life criteria of hydrothermal liquefaction wastewater via ecotoxicity test and modeling

Wastewater resulting from hydrothermal liquefaction (HTL-AP) of biowaste is gaining attention as an emerging hazardous material. However, there is a lack of specific and systematic ecotoxicity studies on HTL-AP. This study addresses this gap by conducting acute toxicity tests on HTL-AP using typical aquatic species and integrating these results with predicted toxicity values from interspecies correlation estimation models to establish aquatic life criteria. HTL-AP exhibited significant toxicity with LC50 of 956.12–3645.4 mg/L, but demonstrated moderate toxicity compared to common freshwater pollutants like commercial microbicides, personal care products, and insect repellents. The resulting hazardous concentration for 5 % of species (HC5), the criterion maximum concentration, and the short-term water quality criteria for aquatic were 506.0, 253.0, and 168.7 mg/L, respectively. Notably, certain organisms like Misgurnus anguillicaudatus and Cipangopaludina chinensis showed high tolerance to HTL-AP, likely due to their metabolic capabilities on HTL-AP components. The significant decrease in HC5 values for some HTL-AP substances compared to pure compounds could indicate the synergistic inhibition effects among HTL-AP compositions. Furthermore, according to the established criteria, HTL-AP required significantly less diluted water (13 t) than carbendazim (1009 t) to achieve biosafety, indicating a safer release. This research establishes a preliminary water quality criterion for HTL-AP, offering a valuable reference for risk assessment and prediction in the utilization of HTL-AP within environmental contexts.

Metabolites from Aerial Parts of Glycyrrhiza foetida as Modulators of Targets Related to Metabolic Syndrome.

A detailed phytochemical investigation has been carried out on the aerial parts of G. foetida leading to the isolation of 29 pure compounds, mainly belonging to the amorfrutin and polyphenol classes. Among them, the new amorfrutin N (5) and exiguaflavone L (21) were isolated and their structures elucidated by means of HR-ESIMS and NMR. All the isolated compounds were investigated for modulation of mitochondrial activity and stimulation of glucose uptake via GLUT transporters, two metabolic processes involved in intracellular glucose homeostasis, which, therefore, correlate with the incidence of metabolic syndrome. These experiments revealed that amorfrutins were active on both targets, with amorfrutin M (17) and decarboxyamorfrutin A (2) emerging as mitochondrial stimulators, and amorfrutin 2 (12) as a glucose uptake promoter. However, members of the rich chalcone/flavonoid fraction also proved to contribute to this activity.

Preparation and characterization of citreorosein nanoparticles with improved bioavailability and cytotoxic potential

The present study was designed to improve the aqueous solubility and dissolution rate of citreorosein, a poorly water soluble drug, by producing its nanoparticles (NPs) using an “antisolvent precipitation with a syringe pump” (APSP) method. Various process parameters including flow rate, stirring speed, temperature, drug concentration and solvent-antisolvent ratio were investigated and optimized to obtain the smallest particle size of citreorosein. The prepared NPs were subjected to different analytical techniques such as SEM, FTIR, XRD and DLS. The NPs were tested for different dissolution parameters including difference (f1) and similarity factors (f2), dissolution efficiency (DE) and mean dissolution time (MDT). The antioxidant potential of citreorosein and its NPs were evaluated using DPPH, ABTS, and FRAP models, while their cytotoxicity was tested on various cancer cell lines such as breast (MDA-MB-231), lung (A549) and liver (HepG2), using the MTT assay. The specificity of the test compound was investigated against two normal human primary epithelial cells including renal (HRPTEpiC) and alveolar (HPAEpiC) cells. DLS analysis revealed that the prepared NPs were less than 200 nm in size while SEM and XRD confirmed their rod shape and amorphous nature, respectively. Citreorosein-NPs exhibited enhanced solubility and dissolution rate in all medias as compared to pure citreorosein. The NPs displayed significant antioxidant effects against ABTS, DPPH and FRAP models, with IC50 values of22.6, 21.45 and 27.30 µg/ml, respectively. Moreover, it showed significant cytotoxic activity against MDA-MB-231, A549 and HepG2 cells, with IC50 values of 3.45, 4.5 and 6.23 µg/ml, respectively. Furthermore, the NPs demonstrated high selectivity index values for the aforementioned cell lines as compared to reference drugs. This study demonstrated that APSP method successfully produced citreorosein-NPs and hence, showed better aqueous solubility, dissolution rate, antioxidant and cytotoxic activities than the pure compound.

L‐proline‐based DES in Knoevenagel synthesis of arylidene rhodanines, thiazolidine‐2,4‐diones, and barbituric derivatives

AbstractDeep eutectic solvents (DES) are environmentally friendly solvents that prevent the use of toxic organic solvents and have been extensively studied in recent years. However, volatile organic compounds (VOC) are often still used during workup and isolation of products. Here, a zero‐VOC strategy for Knoevenagel reaction is reported. (Hetero)aromatic aldehydes are successfully condensed with rhodanine, thiazolidine‐2,4‐dione TZD, or barbituric acid under mild conditions in an L‐proline‐based DES and pure compounds are obtained after hydrolysis without any purification. For the less reactive TZD, activation by microwave allows diminution of reaction time from 24 h to just 1 h.

Nutraceutical Aspects of Selected Wild Edible Plants of the Italian Central Apennines

All over the world, wild edible plants are an essential source of chemical components that justify their use in folk medicine. The aim of this review is to document and summarize the knowledge of ten wild plants analyzed in a previous study for their ethnomedical significance. Achillea millefolium, Borago officinalis, Foeniculum vulgare, Gentiana lutea, Juniperus communis, Laurus nobilis, Malva sylvestris, Satureja montana, Silybum marianum and Urtica dioica were the subjects of our study. They are commonly found in the central Italian Apennines and the Mediterranean basin. Phytochemicals contained in wild plants, such as phenols, polyphenols, flavonoids, condensed tannins, carotenoids, etc., are receiving increasing attention, as they exert a wide range of biological activities with resulting benefits for human health. Based on the 353 studies we reviewed, we focused our study on the following: (a) the ethnobotanical practices and bioactive phytochemicals; (b) the composition of polyphenols and their role as antioxidants; (c) the methodologies commonly used to assess antioxidant activity; (d) the most advanced spectroscopic and spectrometric techniques used to visualize and characterize all components (metabolomic fingerprinting). The potential of pure compounds and extracts to be used as nutraceuticals has also been highlighted through a supposed mechanism of action.