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Chemical investigation of the EtOAc extract from the aerial parts of Acrostichum aureum distributed along coastlines of Vietnam lead to the isolation of a new ecdysteroid, named pterosterone 20,22-acetonide (1), along with twelve known compounds (2-13). Their structures were elucidated by spectroscopic methods including 1D, 2D NMR and HR-ESI-MS analysis as well as comparison with the results of previous studies. Five ecdysteroids (1-5) were evaluated for their cytotoxic activity against the LU-1, MCF7 and HepG2 human cancer cell lines using the SRB assay. Ecdysteroids 1 and 2 having a 20,22-dimethyl acetal group showed cytotoxicity against all tested cell lines with IC50 values in the range 51.59 to 60.14 µM. The other compounds were considered as inactive in this test. [ABSTRACT FROM AUTHOR]

Featured Application: The specific application of this work lies in the new avenue synthesis of nanomedicines—particularly Ag-mNPs, AgSeO2-bmNPs, and Ag-TiO2-bmNPs—using eco-friendly methods. These nanoparticles have shown significant potential as they can be used for potent antioxidant and antibacterial activities. The use of Beta vulgaris extract for the bio-reduction process adds to the environmentally sustainable aspect of the research. Furthermore, the antioxidant activity of the nanoparticles supports their potential medical applications beyond antibacterial therapy. Additionally, the study paves the way for future research into utilizing nature-inspired approaches for green and effective medical advancements. The synthesis of novel nanomedicines through eco-friendly protocols has been applied on a large scale with the prediction of discovering alternate therapies. The current work attained phytogenic synthesis of Ag-mNPs, AgSeO2-bmNPs, and Ag-TiO2-bmNPs through bio-reduction using an aqueous extract of Beta vulgaris (red beetroot). The phytochemical profile of the eco-friendly synthesized metallic/bimetallic nanoparticles was studied. The optical properties of nano-solutions were studied via UV-visible spectroscopy. The Fourier-transform infrared spectroscopy (FT-IR) spectral analyses revealed that stretching vibrations at wavenumbers 3303.81–3327.81 cm−1 attributed to phenolic hydroxyl groups documented shifts in the values in this range owing to proton dissociation through the bio-reduction of the metal ions. The surface morphology and the charge of the nanoparticles were investigated using a Transmission Electron Microscope (TEM) and zeta potential analyses. The prepared nano-solutions showed lower antioxidant activity (1,1-Diphenyl-2-picrylhydrazyl (DPPH•) and phosphomolybdate assays) than the plant extract. These results together with phytochemical analyses support the participation of the reactive species (phenolic contents) in the bio-reduction of the metal ions in the solutions through the formation of metallic/bimetallic nanoparticles. Ag-mNPs, AgSeO2-bmNPs, and Ag-TiO2-bmNPs showed antibacterial potentiality. AgSeO2-bmNPs were superior with inhibitory zone diameters of 34.7, 37.7, 11.7, and 32.7 mm against Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, and Salmonella enterica, respectively. Applying the Methylthiazole Tetrazolium (MTT) assay, the Ag-TiO2 bmNPs revealed potent cytotoxicity against the HePG2 tumor cell line (IC50 = 18.18 ± 1.5 µg/mL), while Ag-SeO2 bmNPs revealed the most potent cytotoxicity against the MCF-7 cell line (IC50 = 17.92 ± 1.4 µg/mL). [ABSTRACT FROM AUTHOR]

Abstract Computational tools in investigating of spectral heterocyclic compounds ranges based on pyrimidine‑2‑thiones, take some importance in identifying their molecular and electronic behavior. Some charcoal heterocyclic compounds were previously synthesized in our laboratory and their experimental results were compared with the computational evaluation. Computational spectroscopic analytical items (IR, NMR and UV–Vis) were calculated using the more popular DFT methods and the predicted results were compared with the reported experimental ones. Quantum and chemical parameters were calculated and molecular electrostatic surface potential (MEP) was studied which predicted the highly electronic sites around the compounds. Some molecular properties (ionization energy, electron affinity, energy gap, hardness, electronegativity, electrophilicity index, static dipole moment and average linear polarizability) of these Schiff bases which were computed at B3LYP/6-31G(d,p) level in aqueous phase. Benchmark analysis was performed for three ab initio functionals such B3LYP, BPV86 and B3PW91 methods to explain the data resulted from NMR spectra. The docking study of some selected previously synthesized compounds was performed using the viral Mpro enzyme protein in compared to a k36 reference ligand inhibitor. The study indicated the ability of the synthesized compounds to form H-bond and hydrophobic (VDW, π-alkyl and π-sulfur) interactions with Mpro enzyme receptor with high inhibition effect of compound L2.

A previously undescribed sesquiterpene lactone, named eupalinolide N (1), was isolated from traditional Chinese medicine "Ye-Ma-Zhui" (Eupatorium lindleyanum) by ethanol reflux extraction, reduced pressure concentration, macroporous resin column chromatography, and C18 reversed-phase chromatography. Its structure was elucidated by a comprehensive interpretation of spectroscopy evidence as well as ECD calculations. 1 showed anti-inflammatory activity by inhibiting the gene expressions of pro-inflammatory factors including IL-1ß, TNFa COX-2, and iNOS at the concentration of 7.5 µM, as well as attenuating the excretion of NO, IL-6, and TNF-a in Raw 264.7 macrophages at the concentration of 15 µM. [ABSTRACT FROM AUTHOR]

Computational tools in investigating of spectral heterocyclic compounds ranges based on pyrimidine‑2‑thiones, take some importance in identifying their molecular and electronic behavior. Some charcoal heterocyclic compounds were previously synthesized in our laboratory and their experimental results were compared with the computational evaluation. Computational spectroscopic analytical items (IR, NMR and UV–Vis) were calculated using the more popular DFT methods and the predicted results were compared with the reported experimental ones. Quantum and chemical parameters were calculated and molecular electrostatic surface potential (MEP) was studied which predicted the highly electronic sites around the compounds. Some molecular properties (ionization energy, electron affinity, energy gap, hardness, electronegativity, electrophilicity index, static dipole moment and average linear polarizability) of these Schiff bases which were computed at B3LYP/6-31G(d,p) level in aqueous phase. Benchmark analysis was performed for three ab initio functionals such B3LYP, BPV86 and B3PW91 methods to explain the data resulted from NMR spectra. The docking study of some selected previously synthesized compounds was performed using the viral Mpro enzyme protein in compared to a k36 reference ligand inhibitor. The study indicated the ability of the synthesized compounds to form H-bond and hydrophobic (VDW, π-alkyl and π-sulfur) interactions with Mpro enzyme receptor with high inhibition effect of compound L2. [ABSTRACT FROM AUTHOR]

The synthesis of novel nanomedicines through eco-friendly protocols has been applied on a large scale with the prediction of discovering alternate therapies. The current work attained phytogenic synthesis of Ag-mNPs, AgSeO2-bmNPs, and Ag-TiO2-bmNPs through bio-reduction using an aqueous extract of Beta vulgaris (red beetroot). The phytochemical profile of the eco-friendly synthesized metallic/bimetallic nanoparticles was studied. The optical properties of nano-solutions were studied via UV-visible spectroscopy. The Fourier-transform infrared spectroscopy (FT-IR) spectral analyses revealed that stretching vibrations at wavenumbers 3303.81–3327.81 cm−1 attributed to phenolic hydroxyl groups documented shifts in the values in this range owing to proton dissociation through the bio-reduction of the metal ions. The surface morphology and the charge of the nanoparticles were investigated using a Transmission Electron Microscope (TEM) and zeta potential analyses. The prepared nano-solutions showed lower antioxidant activity (1,1-Diphenyl-2-picrylhydrazyl (DPPH•) and phosphomolybdate assays) than the plant extract. These results together with phytochemical analyses support the participation of the reactive species (phenolic contents) in the bio-reduction of the metal ions in the solutions through the formation of metallic/bimetallic nanoparticles. Ag-mNPs, AgSeO2-bmNPs, and Ag-TiO2-bmNPs showed antibacterial potentiality. AgSeO2-bmNPs were superior with inhibitory zone diameters of 34.7, 37.7, 11.7, and 32.7 mm against Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, and Salmonella enterica, respectively. Applying the Methylthiazole Tetrazolium (MTT) assay, the Ag-TiO2 bmNPs revealed potent cytotoxicity against the HePG2 tumor cell line (IC50 = 18.18 ± 1.5 µg/mL), while Ag-SeO2 bmNPs revealed the most potent cytotoxicity against the MCF-7 cell line (IC50 = 17.92 ± 1.4 µg/mL).

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In this study, investigation on the essential oils and ethanol extracts of naturally grown and cultivated Satureja macrantha samples were reported. The essential oil, flavour and terpenoid-steroid-flavonoid contents of S. macrantha samples were determined by GC-MS and their phenolic contents by LC-MS/MS. Besides, the biological activities of the samples were investigated for their antioxidant, anti-Alzheimer, antimicrobial, cytotoxic, antityrosinase, antiurease, antielastase and anticollagenase properties. The phenolic content and antioxidant capacity of the cultivated sample were higher than those of the naturally grown sample. According to the GC-MS results, terpinene-4-ol (30.9%) and p-cymene (56.7%) were determined as the major components in the essential oils of the naturally grown and cultivated S. macrantha, respectively. The flavour analysis results showed that cis-sabinene hydrate (20.7%) and carvacrol (42.2%) were found to be the major components in the naturally grown and cultivated samples, respectively. While the naturally grown sample was rich in abietane diterpenoids (ferruginol (17.5 mg analyte/g extract) and sugiol (4.2 mg analyte/g extract)), these components were not detected in the cultivated sample. The rosmarinic acid content (0.20 and 24.87 mg analyte/g extract, respectively) of the cultivated sample was found to be significantly higher than that of the natural sample. The biological activities of the samples were determined to be changed in parallel with their chemical contents that are due to factors such as climatic conditions, and soil structure. [ABSTRACT FROM AUTHOR]

Cueva de Ardales in Málaga, Spain, is one of the richest and best-preserved Paleolithic painted caves of southwestern Europe, containing over a thousand graphic representations. Here, we study the red pigment in panel II.A.3 of "Sala de las Estrellas," dated by U-Th to the Middle Paleolithic, to determine its composition, verify its anthropogenic nature, infer the associated behaviors, and discuss their implications. Using optical microscopy, scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, micro-Raman spectroscopy, and X-ray diffraction, we analyzed a set of samples from the panel and compared them to natural coloring materials collected from the floor and walls of the cave. The conspicuously different texture and composition of the geological samples indicates that the pigments used in the paintings do not come from the outcrops of colorant material known in the cave. We confirm that the paintings are not the result of natural processes and show that the composition of the paint is consistent with the artistic activity being recurrent. Our results strengthen the hypothesis that Neanderthals symbolically used these paintings and the large stalagmitic dome harboring them over an extended time span. [ABSTRACT FROM AUTHOR]

Three-dimensional chitosan-gallic acid complexes were proposed and prepared for the first time by a simple adsorption process of gallic acid (GA) on three-dimensional chitosan structures (3D chitosan). Highly porous 3D devices facilitate a high GA load, up to 2015 mmol/kg at pH 4.0. The preservation of the redox state of GA released from 3D chitosan was confirmed by spectroscopic analyses. The antioxidant activity of 3D chitosan-GA complexes was assessed using the DPPH radical scavenging assay and was found to be dramatically higher than that of free chitosan. The mechanical property of 3D chitosan–GA complexes was also evaluated using a compression test. Finally, 3D chitosan–GA complexes showed a significant antimicrobial capacity against E. coli and S. aureus, selected, respectively, as a model strain for Gram-negative and Gram-positive bacteria. Our study demonstrated a new, simple, and eco-friendly approach to prepare functional chitosan-based complexes for nutraceutical, cosmeceutical, and pharmaceutical applications.

Pleurotus ostreatus (Jacq. :Pers.) Roll is a grey edible mushroom (Agaricochaete), containing a variety of vitamins, minerals and different kind of secondary metabolites. Two new terpenoid indole alkaloids (Terpendole N and Terpendole O) were isolated from the fermentation of P. ostreatus. Their structures were elucidated by 1D, 2D NMR, HR-ESI-MS, and ECD. [ABSTRACT FROM AUTHOR]

Two new 2(1H)-pyrazinone derivatives, 3,6-diisopropyl-5-methylpyrazin-2(1H)-one (1) and 5- (hydroxymethyl)-3,6-diisopropylpyrazin-2(1H)-one (2), were isolated from the fermentation broth of endophytic actinomycete Streptomyces sp. KIB-H1992. Their structures were established based on the detailed spectroscopic analyses, including ESI-MS, HR-ESI-MS, 1D and 2D NMR spectra. [ABSTRACT FROM AUTHOR]

The effect of concentration and origin of dissolved organic matter (DOM) on acenaphthene (Ace) photodegradation in liquid water and ice was investigated, and the components in DOM which were involved in Ace photodegradation were identified. The DOM samples included Suwannee River fulvic acid (SRFA), Elliott soil humic acid (ESHA), and an effluent organic matter (EfOM) sample. Due to the production of hydroxyl radical (•OH) and triplet excited-state DOM (3DOM*) which react with Ace, DOM had promotion effects on Ace photodegradation. However, the promotion effects of DOM were prevailed over by their suppressing effect of DOM including screening light effect, intermediates reducing effect and RS quenching effect, and thus, the photodegradation rates of Ace decreased in the presence of the three DOM with concentrations of 0.5–7.5 mg C/L in liquid water and ice. ESHA had higher light absorption and thus had higher screening light effect on Ace photodegradation in liquid water than SRFA and EfOM. At each DOM concentration, ESHA exhibited higher promotion effect on Ace photodegradation than SRFA and EfOM, in liquid water and ice. The binding of Ace with DOM was indicated by decreases in fluorescence intensity of Ace when coexisted with DOM. However, the binding of Ace to DOM played an unimportant role in suppressing Ace photodegradation. The photodegradation behavior of fluorophores in Ace with DOM present in ice was not similar to that in liquid water. C–O, C═O, carboxyl groups O–H and aliphatic C–H functional groups in DOM were involved in the interaction of DOM with Ace. The presence of Ace seemed to have no influence on the photodegradation behavior of functional groups in DOM. [Display omitted] • Direct photolysis kinetics of Ace were similar in liquid water and ice. •0.5–7.5 mg C/L DOM exhibited suppressing effect on Ace photodegradation. •.•OH and 3DOM* generated form DOM played important roles in Ace photodegradation •Production of functional groups from direct Ace photolysis was different in water and ice. •Photodegradation of fluorophores in Ace with DOM present was different in water and ice. [ABSTRACT FROM AUTHOR]

The usefulness of the structure of galloyl hydrazide (3,4,5-trihydroxybenzohydrazide, coded as 2nz in this article) as a privileged structural system in pharmaceutical organic and medicinal chemistry has prompted the advances of the further therapeutic potentials of this known antioxidant/antitumor compound and, in addition to that, it acts generally as a very important organic reaction intermediate for molecule planning (including synthesis of many important biologically active molecules), as it undergoes various types of chemical reactions. The data of the two synthetic methods (including the new green one), presented in this research article, provides sharp adequate chemical data about the challenging synthesis, separation (purification), and characterization of this compound. A new and very fast one-pot solventless greener microwave-assisted method of synthesis, in addition to the much slower old conventional one, is used in this present research; and followed by full precise purification and characterization (including chromatographic separation; physicochemical identification; IR, 1H-NMR, 13C-NMR, and mass spectroscopic analyses along with elemental analyses for structure elucidation) of 2nz. • Galloyl hydrazide is a very important and unique organic chemical intermediate with, mainly, antioxidant and anticancer biological activities. • Galloyl hydrazide synthesis in the previous literature is very challenging, confusing, not standardized, and without any consensus. • The main objective of this new research is to make two standard and fixed methods of synthesis (conventional and greener) of galloyl hydrazide through designing and constructing a new one-pot solventless greener microwave-assisted synthetic method, in addition to redesigning and qualifying the old traditional conventional heating one; both methods are followed by very accurate identification and characterization data (which can be referenced for the efficient reproducibility in the organic and pharmaceutical chemistry community) of galloyl hydrazide.

Abstract In the present study, the macroscopic sorption behaviors and microscopic immobilization mechanisms of Ni(II) at cryptomelane/water interfaces were explored using the combination of batch sorption technique, desorption procedure, theoretical simulation, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and extended X-ray absorption fine structure (EXAFS) analyses. The good simulation of the pseudo-second-order model on the sorption kinetics data suggests a driving force of chemical sorption rather than mass transport or physical interaction. The sorption trends and uptake mechanisms are obviously related to the solution pH, with cation exchange or outer-sphere surface complexation at an acidic pH of 4.0, inner-sphere surface complexation in both the edge-shared (ES) and double corner-shared (DCS) modes at a neutral pH of 7.0, and precipitation of α-Ni(OH) 2 (s) phase at a highly alkaline pH of 10.0. The gradual increase of Ni(II) sorption amount with solution temperature rising from 293 K to 333 K is consistent with the increased ratio of the weak DCS configuration. The research findings herein can help us better understand the migration and transformation trends of Ni(II) in the manganese mineral-riched aquatic environment. Graphical abstract Image 1 Highlights • Interaction mechanisms of Ni(II) with cryptomelane were explored by combining multiple techniques. • Relative contributions of different uptake processes were verified from ligand extraction data. • Ni(II) binding modes were clearly identified with theoretical simulation and spectroscopic analyses. • Temperature rising enhanced the sorption amount of Ni(II) in double corner-shared binding mode. • Research findings facilitated the assessment of Ni(II) migration and fate in Mn-riched environment. [ABSTRACT FROM AUTHOR]

The materials used in the historical restoration of a fossil collection named “Problematica Verrucana”, have been studied in order to contribute to the creation of a catalogue of restoration materials used in the past. Due to the complexity of the mixtures used with different purposes to restore fossil finds, an extractive technique has been employed in order to separate the compounds soluble in solvents with different polarities. Using this procedure several components, even when found in small amounts, have been identified. The chemical composition of the organic and inorganic compounds used in the restoration material has been determined using extractive procedure, FT-IR and 1H-NMR spectroscopies. A preliminary macroscopic characterisation and mineralogical and petrographical analyses have also been performed on the inorganic filling materials found in several samples. The different compositions of various materials used in the restoration of this fossil collection might be related to the particular conservative and esthetic functions of the product applied on the find.

[Display omitted] • Synthesis of new six complexes of Cr(III), Fe(III), Co(II), Ni(II), Cu(II) and Zn(II) with L in presence of Bipy. • Characterization of L, Bipy and their metal complexes with different techniques. • Optimized geometries for the compounds using DFT. • Evaluation of the antimicrobial activities for the compounds against some Gram-positive, Gram-negative bacteria and fungi. Cr(III), Fe(III), Co(II), Ni(II), Cu(II), and Zn(II) interacted with 1-[4-(4-methoxyphenyl)-6-methyl-2-thioxo-1,2,3,4-tetrahydropyrimidin-5-yl]ethanone (L) to form six mixed ligand metal complexes in existence of 2,2′-bipyridine (Bipy).The produced compounds were described utilizing elemental analyses, FT-IR, UV–vis., 1H NMR spectra, thermal analyses (TG-DTG and DTA), X-ray powder diffraction method (XRD), molar conductance and magnetic moment. The IR showed that L bonded with metal ions as bidentate ligand through nitrogen and sulfur atoms, while, Bipy coordinated across nitrogen atoms. According to the molar conductance measurements the complexes are electrolytes. For all complexes the octahedral geometry were supported by employing the magnetic moments and electronic spectra. The degradation pathways for L , Bipy and their complexes utilizing TG and DTG were determined and thermodynamic parameter (E a , ΔH*, ΔS* and ΔG*) were computed utilizing Horowitz-Metzger (HM) and Coats-Redfern (CR). The average crystalline size (D) and type of each molecule were evaluated using the XRD analysis (crystalline or amorphous). In order to recognize the optimal molecular geometry for the compounds, density functional theory (DFT) simulations were performed. Regarding L , which has σ value of 17.544 eV, all investigated complexes with σ values ranging from 21.053 to 95.238 eV are regarded as soft. Numerous bacterial and fungal strains were used as test subjects for the compound's biological activities. The data show that the current complexes are highly effective and could serve as superior bactericides. [ABSTRACT FROM AUTHOR]

A new phloroglucinol derivative, identified as 3-benzoyl-3-hydroxy-5-(3-methylbut-2-en-1- yl)cyclopentane-1,2,4-trione (1), together with eight previously reported compounds, quercetin, myricitrin, hypericin, biapeginin, pseudohypericin, myricetin, 1,3,5,6-tetrahydroxyxanthone, and β-sitosterol were isolated from the chloroform, ethyl acetate and butanol extracts of the aerial part of Hypericum afrum (Lam.). Their structures were elucidated by spectroscopic analyses, including 1D-, 2D-NMR and HRESIMS. The EtOAc extract showed moderate MAO-A inhibition with an IC50 value of 3.35 μg/mL. Bioassay-guided fractionation of the EtOAc extract resulted in the isolation of quercetin as the active component exhibiting MAO-A inhibitory activity with an IC50 value of 1.25 μM. [ABSTRACT FROM AUTHOR]

Two new prenylated stilbenes with an irregular sesquiterpenyl side chain, solomonin B (1) and solomonin C (2), together with four known compounds, glyasperin A (3), isolated for the first time from propolis, kumatakenin (4), macarangin (5) and mangiferolic acid (6) were isolated from ethanol extract of propolis from Fiji islands. The compounds structures were determined based on their spectral data analysis (1Dand 2D NMR, UV and HREIMS) and comparison with literature data. The chemical composition of propolis from Fiji islands was determined for the first time. [ABSTRACT FROM AUTHOR]

Two new analogs, a carboxy methyl (Argaminolic B) and a carboxy derivative (Argaminolic C), of a recently reported amino phenolic, Argaminolic A, isolated from the fruit of the argan tree, Argania spinosa (Skeels L.), are described. Argaminolic B exhibits facile hydrolysis of its methyl ester to yield Argaminolic C, which then undergoes a remarkably facile decarboxylation to the previously described Argaminolic A. [ABSTRACT FROM AUTHOR]

Four novel cycloheximide derivatives(1-4) and two known compounds--l-cycloheximide(5), and isocycloheximide(6) were obtained from marine-derived Streptomyces sp. h-119, which was isolated from the sediment samples collected in intertidal zone, Zhangzhou, Fujian Province. Their structures were elucidated by spectroscopic analyses, including 1D and 2D-NMR experiments, and by HR-Q-TOF mass spectrometry. Their antimicrobial activities were evaluated. [ABSTRACT FROM AUTHOR]

A new acylated glycoside, 4-O-(4',6'-di-O-galloyl-β-D-glucopyranosyl)-trans-p-coumaric acid, named microcoryn (1), together with sixteen known phenolic compounds, 5-O-(6'-O-galloyl-β-D-glucopyranosyl)-gentisic acid (2), ellagic acid (3), gallic acid (4), kaempferol (5), quercetin (6), 3-O-galloyl-β-D-glucose (7), 2,3,6-tri-O-galloyl-β-D-glucose (8), 1,2,4,6-tetra-O-galloyl-β-D-glucose (9), 1,2,3,4,6-penta-O-galloyl-β-D-glucose (10), 4,6-hexahydroxydiphenoyl-β-D- glucose (11), gemin D (12), tellimagrandin I (13), tellimagrandin II (14), isocoriariin F (15), oenothein C (16), and oenothein B (17) were isolated from the leaves of Eucalyptus microcorys. The structure of the new compound was elucidated by spectroscopic data, especially by 2D NMR techniques. This is the first phytochemical investigation of this plant's leaf extract. [ABSTRACT FROM AUTHOR]

Four new natural compounds, namely 2-deprenyl-7-hydroxy-rheediaxanthone B, (2E)-2-(hydroxylhexyliden)-cyclopropyl-1→3-diglucoside and (6E)-6[2-(β-glucopyranosyloxy)-cyclopropyliden] hexanoic acid methylester as well as the first glucocerebroside from a fern, (4E)-1-O-(β-glucopyranosyl)-N-(2'-hydroxytetracosanoyl)-4,8-sphingadienine (d18:2/h24:0-GlcCer), were isolated for the first time from the rootlets of the tree fern Metaxya rostrata C. Presl. Two of these compounds contain a very rare cyclopropyliden structure which until now is only known from two other compounds from this plant. In addition, this is the first report of the tannin proanthocyanidin A2 and the triterpenes squalene and fern-9(11)-ene in this tree fern, of which the two latter were isolated from the leaves. The structures of all compounds were elucidated on the basis of detailed spectroscopic and mass spectrometric analyses, including 1D-, 2D-NMR and HR Q-TOF-MS. [ABSTRACT FROM AUTHOR]

A new cycloheximide derivative, Cycloheximide acid A (1) and two known compounds (-)-anhydrocycloheximide (2), and l-cycloheximide (3) were isolated from the EtOAc extract of the strain of Streptomyces sp. Z00045. The structure was determined on the basis of comprehensive 1D and 2D (COSY, HMQC, HMBC) NMR and MS analyses. [ABSTRACT FROM AUTHOR]

A new natural product, cytochalasin H2 (1), together with cytochalasin H (2) were obtained from the agar cultures of the strain Xylaria sp. A23, which was isolated from Annona squamosa. The chemical structures of them were elucidated by spectroscopic and mass spectrometric analyses, including 1D-, 2D-NMR and HR-FTMS. Compound 1 showed week cytotoxicity against HeLa and 293T cell lines by MTT assay. [ABSTRACT FROM AUTHOR]

Abstract: The present work aimed to achieve mineralogical and spectroscopic characterization of the Late Cretaceous clays of Aleg formation (Coniacian-Lower Campanian system), Tunisia, for the removal of several toxic metals in aqueous system. The collected clay samples were first characterized by different techniques including X-ray fluorescence (XRF), thermal analysis (TG/TDA), X-ray diffraction (XRD), Fourier transform infrared (FTIR) and scanning electron microscopy (SEM). Results showed that the natural clay samples are mainly composed of silica, alumina, iron, calcium and magnesium oxides. The sorbents are mainly mesoporous materials with modest specific surface area of <71m2/g. Then, the possible use of the studied clay samples as adsorbents for the removal of Pb(II), Cd(II), Cu(II) and Zn(II) from aqueous solutions was evaluated. Langmuir, Freundlich and Dubinin–Radushkevich (D–R) isotherm models were used to simulate the equilibrium data. The maximum adsorption capacity varied between 6.78 and 131.58mg/g, showing much higher removal efficiency than the relevant previous studies. Langmuir isotherms showed the best fitting to the experimental data. Among the studied clay samples, the amount of calcium carbonates was the most influencing parameter for heavy metal removal. The results suggest that the studied clay samples can be effectively used for the treatment of contaminated wastewaters. [Copyright &y& Elsevier]

The release kinetics for a variety of proteins of a wide range of molecular mass, hydrodynamic radii, and isoelectric points through a nanofiber hydrogel scaffold consisting of designer self-assembling peptides were studied by using single-molecule fluorescence correlation spectroscopy (FCS). In contrast to classical diffusion experiments, the single-molecule approach allowed for the direct determination of diffusion coefficients for lysozyme, trypsin inhibitor, BSA, and IgG both inside the hydrogel and after being released into the solution. The results of the FCS analyses and the calculated pristine in-gel diffusion coefficients were compared with the values obtained from the Stokes-Einstein equation, Fickian diffusion models, and the literature. The release kinetics suggested that protein diffusion through nanofiber hydrogels depended primarily on the size of the protein. Protein diffusivities decreased, with increasing hydrogel nanofiber density providing a means of controlling the release kinetics. Secondary and tertiary structure analyses and biological assays of the released proteins showed that encapsulation and release did not affect the protein conformation and functionality. Our results show that this biocompatible and injectable designer self-assembling peptide hydrogel system may be useful as a carrier for therapeutic proteins for sustained release applications. [ABSTRACT FROM AUTHOR]

Versatile peroxidase (VP) is defined by its capabilities to oxidize the typical substrates of other basidiomycete peroxidases: (i) Mn2+, the manganese peroxidase (MnP) substrate (Mn3+ being able to oxidize phenols and initiate lipid peroxidation reactions); (ii) veratryl alcohol (VA), the typical lignin peroxidase (LiP) substrate; and (iii) simple phenols, which are the substrates of Coprinopsis cinerea peroxidase (CIP). Crystallographic, spectroscopic, directed mutagenesis, and kinetic studies showed that these ‘hybrid’ properties are due to the coexistence in a single protein of different catalytic sites reminiscent of those present in the other basidiomycete peroxidase families. Crystal structures of wild and recombinant VP, and kinetics of mutated variants, revealed certain differences in its Mn-oxidation site compared with MnP. These result in efficient Mn2+ oxidation in the presence of only two of the three acidic residues forming its binding site. On the other hand, a solvent-exposed tryptophan is the catalytically-active residue in VA oxidation, initiating an electron transfer pathway to haem (two other putative pathways were discarded by mutagenesis). Formation of a tryptophanyl radical after VP activation by peroxide was detected using electron paramagnetic resonance. This was the first time that a protein radical was directly demonstrated in a ligninolytic peroxidase. In contrast with LiP, the VP catalytic tryptophan is not β-hydroxylated under hydrogen peroxide excess. It was also shown that the tryptophan environment affected catalysis, its modification introducing some LiP properties in VP. Moreover, some phenols and dyes are oxidized by VP at the edge of the main haem access channel, as found in CIP. Finally, the biotechnological interest of VP is discussed. [ABSTRACT FROM PUBLISHER]

Large volumes of wastewater with a high organic load are generated by the pulp and paper industry that negatively affect the quality of receiving waters. The main waste products in the pulp mill effluents are lignin derived macromolecular compounds, which are similar to natural humic substances and very resistant to wastewater treatments. Fulvic acids (FA) represent the higher percentage of these humic substances and it was observed that solar irradiation modify their properties. Several analytic tools, namely, UV–Visible, molecular fluorescence and FTIR spectroscopies, were used to assess the effect of solar exposition on fulvic acids from a kraft pulp mill effluent. It may be concluded that sun irradiation may alter to a high extent the physicochemical properties of macromolecular organic matter, namely fulvic acids, released by kraft pulp mill effluents. After solar exposition, the aromaticity decreases, the aliphatic structures become more oxygenated, and the fulvic acids from the pulp mill effluent remaining in solution are more similar to aquatic fulvic acids from non polluted sites. [Copyright &y& Elsevier]