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1.
Insect Sci ; 28(2): 392-402, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32394613

RESUMO

Owing to their potential applications, as well as their structural diversity, the discovery of novel secondary metabolites from insect-associated fungi has been of interest to researchers in recent years. The aim of this study was therefore to estimate the diversity of fungi associated with fungus-growing termites and bioprospecting these for potential secondary metabolites. In total, 18 fungal species were isolated and described from the gut and comb of Macrotermes barneyi based on 18S ribosomal DNA gene sequence analysis. Antimicrobial activity assays were carried out on all the known fungi, and nine isolates were recorded as active against pathogenic fungi. Xylaria escharoidea, the best performing isolate, was grown at laboratory scale and 4,8-dihydroxy-3,4-dihydronaphthalen-1(2H) was isolated and characterized. The minimum inhibitory concentration of this isolated compound against tested pathogenic organisms was found to be 6.25 µg. In addition, molecular docking studies have revealed that 4,8-dihydroxy-3,4-dihydronaphthalen-1(2H) is a prominent antibacterial agent with a marked interaction with key residues on protein A (agrAC ) that regulates the accessory gene. The findings of this study support the drug discovery of antimicrobial properties in insect-associated fungi, which may lead to novel secondary metabolites.


Assuntos
Anti-Infecciosos/isolamento & purificação , Ascomicetos/química , Fungos/isolamento & purificação , Isópteros/microbiologia , Naftalenos/isolamento & purificação , RNA Ribossômico 18S/análise , Animais , Anti-Infecciosos/química , Fungos/classificação , Fungos/fisiologia , Naftalenos/química , RNA Fúngico/análise , Análise de Sequência de DNA , Simbiose
2.
J Chromatogr A ; 1635: 461732, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33285416

RESUMO

The performance of comprehensive two-dimensional gas chromatography coupled to mass spectrometry (GC×GC-MS) using a column combination of a non-polar stationary phase (DB-5MS) and an ionic liquid stationary phase (SLB-IL60) in the first- and the second dimension has been evaluated for the suitable separation of polychlorinated naphthalenes (PCNs). The optimization of the GC×GC-MS method was carried out using different oven temperature programs and modulation conditions, achieving the best results using a ramp temperature rate of 0.75 °C min-1 and a modulation time of 12 s. Under these conditions, efficient separation of all PCN congeners present in Halowax formulations was achieved in 140 min, resolving some critical closed eluting isomers, such as CN-33/34/37, highly toxic CN-66/67 or CN-71/72 pairs, among others. These findings represent a significant improvement in the congener-specific separation of PCNs over the 1D-GC and GC×GC methodologies already published and the DB-5MS × SLB-IL60 column combination offered the orthogonality required for the congener-specific determination with a high peak capacity. The GC×GC-MS method was applied to the characterisation of Halowax formulations, obtaining similar compositional profiles than those previously reported.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Líquidos Iônicos/química , Naftalenos/isolamento & purificação , Naftalenos/análise , Temperatura
3.
Mar Drugs ; 18(10)2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33053770

RESUMO

Two new nitrogen-containing metabolites, designated hatsusamide A (1) and B (2), were isolated from a culture broth of Penicilliumsteckii FKJ-0213 together with the known compounds tanzawaic acid B (3) and trichodermamide C (4) by physicochemical (PC) screening. The structures of 1 and 2 were determined as a tanzawaic acid B-trichodermamide C hybrid structure and a new analog of aspergillazines, respectively. The absolute configuration of 1 was determined by comparing the values of tanzawaic acid B and trichodermamide C in the literatures, such as 1H-nuclear magnetic resonance (1H-NMR) data and optical rotation, after hydrolysis of 1. Compounds 1-4 were evaluated for cytotoxicity and anti-malarial activities. Compounds 1 and 3 exhibited weak anti-malarial activity at half-maximal inhibitory concentration (IC50) values of 27.2 and 78.5 µM against the K1 strain, and 27.9 and 79.2 µM against the FCR3 strain of Plasmodium falciparum, respectively. Furthermore, 1 exhibited cytotoxicity against HeLa S3, A549, Panc1, HT29 and H1299 cells, with IC50 values of 15.0, 13.7, 12.9, 6.8, and 18.7 µM, respectively.


Assuntos
Organismos Aquáticos/crescimento & desenvolvimento , Organismos Aquáticos/metabolismo , Penicillium/crescimento & desenvolvimento , Penicillium/metabolismo , Antimaláricos/química , Antimaláricos/isolamento & purificação , Antimaláricos/farmacologia , Organismos Aquáticos/isolamento & purificação , Linhagem Celular Tumoral , Citotoxinas/química , Citotoxinas/isolamento & purificação , Citotoxinas/farmacologia , Diterpenos/química , Diterpenos/isolamento & purificação , Diterpenos/farmacologia , Ácidos Graxos Insaturados/química , Ácidos Graxos Insaturados/isolamento & purificação , Ácidos Graxos Insaturados/farmacologia , Humanos , Naftalenos/química , Naftalenos/isolamento & purificação , Naftalenos/farmacologia , Penicillium/isolamento & purificação , Espectroscopia de Prótons por Ressonância Magnética , Difração de Raios X
4.
Artigo em Inglês | MEDLINE | ID: mdl-32947191

RESUMO

This study aimed to optimize a new sample preparation method using N-doped mesoporous carbon sorbent for simultaneous measurement of 1-naphthol and 2-naphthol, the biomarkers of exposure to naphthalene. The samples were analyzed using high-performance liquid chromatography supplied with ultraviolet detector (HPLC-UV). N-doped mesoporous carbon sorbent was obtained via the hard template procedure. The synthesized nanosorbent was then characterized by transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET), and elemental analysis (CHN). The effective factors in the extraction of the studied biomarkers were examined by the Box-Behnken (BBD) methodology. Regarding the optimum conditions, the sketched calibration curve for naphthols was linear in the concentration levels of 1-600 µg L-1 for human urine samples. The accuracy and reproducibility of the introduced method were determined using the relative recovery (RR %) and relative standard deviation (RSD %) tests on the fortified urine samples. RR% and RSD% were found to be 97.0-101.2% and 3.1-9.0%, respectively. The calculated method detection limit of the optimized procedure was 0.3 µg L-1 and 0.5 µg L-1 for 1-naphthol and 2-naphthol, respectively.


Assuntos
Carbono/química , Cromatografia Líquida de Alta Pressão/métodos , Nanopartículas/química , Naftalenos/urina , Microextração em Fase Sólida/métodos , Biomarcadores/urina , Exposição Ambiental/análise , Humanos , Limite de Detecção , Modelos Lineares , Naftalenos/química , Naftalenos/isolamento & purificação , Reprodutibilidade dos Testes , Sonicação
5.
J Chromatogr A ; 1628: 461486, 2020 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-32822970

RESUMO

In this work, an inexpensive, fast, and selective ionic liquid modified graphene oxide (GO-IL) was synthesized and electrochemically deposited on the inner surface of a stainless-steel tube. Then, it was applied for circulated headspace in-tube solid-phase microextraction (CHS-IT-SPME) of naphthalene from honey samples. Next, the coated tube was replaced with the sample loop of a six-port injection valve for on-line desorption and further HPLC-UV analysis of naphthalene. The sorbent was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FT-IR), and energy-dispersive X-ray spectroscopy (EDX). Different parameters affecting the procedure efficiency, including extraction temperature, extraction time, salt concentration, and sample volume were optimized by central composite design and response surface methodology. Under the optimum conditions, the calibration curve was linear within the range of 0.3-200 ng mL-1, with a regression coefficient of 0.9972. The limits of detection (LOD) and quantification (LOQ) were found to be 0.1 ng mL-1 and 0.3 ng mL-1, respectively. Intra-day and inter-day RSDs% for three replicate measurements of naphthalene at the concentration of 10 ng mL-1 were obtained 3.9% and 5.0%, respectively. Also, good tube-to-tube reproducibility of 5.3% was achieved. Finally, the method was successfully applied for measuring trace amounts of naphthalene in honey samples. Relative recoveries were calculated within the range of 90.0-106.5%, indicating excellent efficiency of the proposed method.


Assuntos
Cromatografia Líquida/métodos , Galvanoplastia/métodos , Grafite/química , Mel/análise , Líquidos Iônicos/química , Naftalenos/isolamento & purificação , Sistemas On-Line , Microextração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão , Limite de Detecção , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Reprodutibilidade dos Testes
6.
Chem Biodivers ; 17(9): e2000424, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32672903

RESUMO

The chemical investigation on endophytic fungus Annulohypoxylon cf. stygium in leaves of Anoectochilus roxburghii (Wall.) Lindl. has been performed. Sixteen compounds were isolated and their structures were identified as (-)-notoamide A, (-)-notoamide B, (+)-versicolamide B, notoamide C, notoamide D, stephacidin A, sterigmatocystin, dihydrosterigmatocystin, secosterigmatocystin, versiconol, averufanin, kipukasin D, kipukasin E, diorcinal, palmarumycin CP2 and (-)-(3R)-mellein methyl ether, respectively, by spectroscopic analysis and comparison with literature data. All the compounds were isolated from Annulohypoxylon genus for the first time. Sterigmatocystin and palmarumycin CP2 showed selective cytotoxic activities against HepG2, HeLa, MCF-7 and HT-29.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Ascomicetos/química , Naftalenos/farmacologia , Orchidaceae/microbiologia , Folhas de Planta/microbiologia , Compostos de Espiro/farmacologia , Esterigmatocistina/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Ascomicetos/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Naftalenos/química , Naftalenos/isolamento & purificação , Compostos de Espiro/química , Compostos de Espiro/isolamento & purificação , Esterigmatocistina/química , Esterigmatocistina/isolamento & purificação
7.
Artigo em Inglês | MEDLINE | ID: mdl-32485631

RESUMO

Dapoxetine is an oral medication used for treatment of premature ejaculation (PE) in men aged (18-64 years). In this study, we present a validated, precise and sensitive method for determination of dapoxetine in human plasma by liquid chromatography/ electrospray ionization-tandem mass spectrometry. Dapoxetine and the internal standard (Dapoxetine- d6) were extracted from plasma via liquid-liquid extraction (LLE). The LC separation was performed utilizing ACE C8 (4.6 X50) mm, 5 µm column. The mobile phase was composed of acetonitrile and buffer (0.01 M Ammonium acetate +0.02% Formic acid solution) (85:15, v/v). The method was linear within the concentration range of 5.0-600 ng/mL for Dapoxetine in human plasma. Short analytical run was achieved with 1.6 min run time. Intra-day and inter-day accuracy was between 97 and 106% with precision (CV, %) of ≤ 5% achieved across all the quality control samples. Dapoxetine was stable in several conditions with recovery rates > 90%. This method was utilized successfully in clinical pharmacokinetic study following oral administration of 60 mg Dapoxetine tablets in 36 healthy male subjects. The result for all 90% confidence intervals were within the preset ranges. The method proved to be highly reproducible and sensitive and thus can be employed in bioequivalence studies and large scale sample analysis of Dapoxetine.


Assuntos
Benzilaminas/sangue , Cromatografia Líquida de Alta Pressão/métodos , Naftalenos/sangue , Espectrometria de Massas por Ionização por Electrospray/métodos , Administração Oral , Adolescente , Adulto , Benzilaminas/administração & dosagem , Benzilaminas/isolamento & purificação , Benzilaminas/farmacocinética , Humanos , Modelos Lineares , Extração Líquido-Líquido , Masculino , Naftalenos/administração & dosagem , Naftalenos/isolamento & purificação , Naftalenos/farmacocinética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Equivalência Terapêutica , Adulto Jovem
8.
Chem Biodivers ; 17(8): e2000315, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32472579

RESUMO

One new naphthalenone, didymelol A, and three new naphthols, didymelol B-D, together with three known naphthalenones, (3S,4R)-3,4,6-trihydroxy-3,4-dihydronaphthalen-1(2H)-one, (4S)-4,6-dihydroxy-3,4-dihydronaphthalen-1(2H)-one, (4S)-4-hydroxy-3,4-dihydronaphthalen-1(2H)-one, were isolated from the Saussurea laniceps endophytic fungus Didymella glomerata X223. The structures of the isolates were elucidated based on extensive spectroscopic data analysis. The absolute configuration of didymelol A was established through single-crystal X-ray diffraction data and didymelols B-D were identified through comparisons of experimental and calculated ECD spectra. All compounds were evaluated for cytotoxic activity against human non-small cell lung cancer A549 cells and human breast carcinoma MDA-MB-435 cells.


Assuntos
Ascomicetos/química , Naftalenos/isolamento & purificação , Naftóis/isolamento & purificação , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Linhagem Celular Tumoral , Cristalografia por Raios X , Humanos , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray
9.
Chem Biodivers ; 17(4): e2000057, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32091654

RESUMO

Two julichrome monomers, julichromes Q11 (1) and Q12 (2), along with five known julichromes (Q10 , Q3 ⋅ 5 , Q3 ⋅ 3 , Q6 ⋅ 6 , Q6 , 3-7) and four known anthraquinones (chrysophanol, 4-acetylchrysophanol, islandicin, huanglongmycin A, 8-11), were isolated from the marine gastropod mollusk Batillaria zonalis-associated Streptomyces sampsonii SCSIO 054. This is the first report of julichromes isolated from a marine source. Extensive dissection of 1D and 2D NMR datasets combined with X-ray crystallography enabled rigorous elucidation of the previously reported configurations of julichrome Q3 ⋅ 5 (4) and related julichrome Q3 ⋅ 3 (5); both of the configuration at C(9) needs to be revised. In addition, julichrome Q12 (2) was found to display antibacterial activity against Micrococcus luteus and Bacillus subtilis with MICs of 2.0 and 8.0 µg mL-1 ; four compounds (1, 3, 6, 7) also showed inhibitory activities against an array of methicillin-resistant Staphylococcus aureus, S. aureus and S. simulans AKA1 with MIC values ranging from 8 to 64 µg mL-1 .


Assuntos
Antibacterianos/química , Gastrópodes/microbiologia , Naftalenos/química , Streptomyces/química , Animais , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Bacillus subtilis/efeitos dos fármacos , Cristalografia por Raios X , Testes de Sensibilidade Microbiana , Micrococcus luteus/efeitos dos fármacos , Conformação Molecular , Naftalenos/isolamento & purificação , Naftalenos/farmacologia , Filogenia , Estereoisomerismo , Streptomyces/classificação , Streptomyces/metabolismo
10.
Chemosphere ; 242: 125157, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31698213

RESUMO

Sequential anaerobic and aerobic processes have been recommended to treat textile wastewater reliably. In this work, the focus was on finding an energetically more competitive system to remove tetra-azo dye Direct Black 22 (DB22). We operated two upflow anaerobic sludge blanket (UASB) reactors (R1 and R2) in three phases (PI, PII, and PIII). R1 was operated as a conventional UASB, while R2 was microaerated in the upper part (0.18 ±â€¯0.05 mg O2. L-1), aiming to remove DB22 simultaneously with the aromatic amine byproducts. PI consisted of feeding reactors with synthetic textile wastewater (STW), PII had higher salinity in the STW, and PIII was the same as PII, plus sulfate. The results showed that color and COD removal efficiencies were similar for both reactors (67-72% for R1 and 59-78% for R2) without a substantial influence of oxygen in R2. However, microaeration played a crucial role in R2 by removing the anaerobically formed aromatic amines; during PIII, the effluent was 16 times less toxic than that of R1. The microbial community that developed in the sludge bed of both reactors was quite similar, with the core microbiome represented by Trichococcus, Syntrophus and Methanosaeta genera. The increase in salinity in PII and PIII promoted a shift in the microbial community, excluding salty-sensitive genera from the core microbiome. The putative genera Brevundimonas and Ornatilinea were associated to aromatic amine microaerobic removal. Therefore, there is a potential application of a compact microaerated anaerobic system for textile wastewater treatment.


Assuntos
Reatores Biológicos/normas , Microbiota , Naftalenos/isolamento & purificação , Têxteis , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Purificação da Água/métodos , Aerobiose , Anaerobiose , Esgotos/microbiologia , Sulfatos , Águas Residuárias/microbiologia
11.
Fitoterapia ; 139: 104401, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31669964

RESUMO

Three previously undescribed (±)-3,4-dihydro-4-naphthyl-naphthalen-1(2H)-one derivatives were isolated from Juglans regia flowers. Elucidation of the 2D structures of these first-reported compounds was completed via regular spectroscopic methods. The assignment of racemic nature of these compounds was achieved using the examination of their chiral HPLC profiles. (±)-2,3-Dihydro-4',8,8'-trihydroxy-(1,1'-binaphthalen)-4(1H)-one, (±)-2,3-dihydro-4',5,8,8'-tetrahydroxy-(1,1'-binaphthalen)-4(1H)-one, and (±)-2,3-dihydro-1',5,5',8-tetrahydroxy-(1,2'-binaphthalen)-4(1H)-one were the structures of these racemic compounds, all taking on central chirality. The resolution of all the racemic compounds was conducted and achieved using a chiral HPLC procedure. The absolute configurations of the three isolated pairs of enantiomers were assigned via time-dependent density functional theory calculations from the electronic circular dichroism data. The findings in this paper demonstrated that the relevant biochemical reactions for the construction of these 3,4-dihydro-4-naphthyl-naphthalen-1(2H)-one derivatives in the test plant are nonselective. The (±)-2,3-dihydro-4',8,8'-trihydroxy-(1,1'-binaphthalen)-4(1H)-one showed selective inhibitory activity on tumor cells growth, preliminarily supporting the application of Juglans regia flowers to protect against cancers in a few Chinese folk areas.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Flores/química , Juglans/química , Naftalenos/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Estrutura Molecular , Naftalenos/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia
12.
J Cell Mol Med ; 23(12): 8269-8279, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31612613

RESUMO

Imbalance of osteoblast and osteoclast in adult leads to a variety of bone-related diseases, including osteoporosis. Thus, suppressing the activity of osteoclastic bone resorption becomes the main therapeutic strategy for osteoporosis. Asperpyrone A is a natural compound isolated from Aspergillus niger with various biological activities of antitumour, antimicrobial and antioxidant. The present study was designed to investigate the effects of Asperpyrone A on osteoclastogenesis and to explore its underlining mechanism. We found that Asperpyrone A inhibited RANKL-induced osteoclastogenesis in a dose-dependent manner when the concentration reached 1 µm, and with no cytotoxicity until the concentration reached to 10 µm. In addition, Asperpyrone A down-regulated the mRNA and protein expression of NFATc1, c-fos and V-ATPase-d2, as well as the mRNA expression of TRAcP and Ctsk. Furthermore, Asperpyrone A strongly attenuated the RNAKL-induced intracellular Ca2+ oscillations and ROS (reactive oxygen species) production in the process of osteoclastogenesis and suppressed the activation of MAPK and NF-κB signalling pathways. Collectively, Asperpyrone A attenuates RANKL-induced osteoclast formation via suppressing NFATc1, Ca2+ signalling and oxidative stress, as well as MAPK and NF-κB signalling pathways, indicating that this compound may become a potential candidate drug for the prevention or treatment of osteoporosis.


Assuntos
Produtos Biológicos/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Fatores de Transcrição NFATC/antagonistas & inibidores , Naftalenos/farmacologia , Osteoclastos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Pironas/farmacologia , Ligante RANK/farmacologia , Animais , Aspergillus niger/química , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Cálcio/metabolismo , Células Cultivadas , Expressão Gênica/efeitos dos fármacos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , Fatores de Transcrição NFATC/genética , Fatores de Transcrição NFATC/metabolismo , Naftalenos/química , Naftalenos/isolamento & purificação , Osteoclastos/metabolismo , Osteogênese/efeitos dos fármacos , Pironas/química , Pironas/isolamento & purificação , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo , Fosfatase Ácida Resistente a Tartarato/genética , Fosfatase Ácida Resistente a Tartarato/metabolismo
13.
J Nat Prod ; 82(10): 2878-2885, 2019 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-31599583

RESUMO

To explore the chemical diversity of metabolites from new species of Dothideomycetes, the ex-type strain of Sparticola junci was investigated. Seven highly oxygenated and functionalized spirodioxynaphthalene natural products incorporating carboxyalkylidene-cyclopentanoid (1-4), carboxyl-functionalized oxabicyclo[3.3.0]octane (5-6), and annelated 2-cyclopentenone/δ-lactone (7) units, sparticolins A-G, were isolated from submerged cultures of the fungus. Their chemical structures including their relative (and absolute) configurations were established through spectroscopic and X-ray crystallographic analyses. Sparticolin B (2) exhibited inhibitory activity against the Gram-positive bacteria Bacillus subtilis, Micrococcus luteus, and Staphylococcus aureus, while sparticolin G (7) showed antifungal activities against Schizosaccharomyces pombe and Mucor hiemalis. All other sparticolins were only weakly active against S. aureus and also showed weak activities against the nematode Caenorhabditis elegans. Compounds 2 and 7 also showed moderate cytotoxic activities against seven mammalian cell lines.


Assuntos
Ascomicetos/metabolismo , Naftalenos/isolamento & purificação , Animais , Caenorhabditis elegans/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Naftalenos/química , Naftalenos/farmacologia
14.
J Mol Model ; 25(9): 297, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31482325

RESUMO

The separation mechanism of chiral drugs in high-pressure liquid chromatography is yet ambiguous. Computational chemistry helps to gain insights about chiral drug separations. The interaction between the 13 drug enantiomers and cellulose tris (3, 5-dimethyl phenyl carbamate) (chiral cel OD) as chiral stationary phase in 3 mobile phases was assayed by AutoDock and LAMMPS simulations. It is found that not only the structure of 2 enantiomers but also the mobile phase has an important role in enantioseparations and sometimes may invert the elution order. The molecular dynamics simulation is a comprehensive method that can be used to investigate the chiral drug enantioseparation mechanism in HPLC.


Assuntos
Anticonvulsivantes/isolamento & purificação , Celulose/análogos & derivados , Ésteres/isolamento & purificação , Etanol/isolamento & purificação , Imidazóis/isolamento & purificação , Naftalenos/isolamento & purificação , Fenilcarbamatos/química , Anticonvulsivantes/química , Celulose/química , Cromatografia Líquida de Alta Pressão/métodos , Ésteres/química , Etanol/química , Humanos , Ligação de Hidrogênio , Imidazóis/química , Cinética , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Naftalenos/química , Teoria Quântica , Soluções , Estereoisomerismo , Termodinâmica
15.
Chem Pharm Bull (Tokyo) ; 67(8): 775-777, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31366826

RESUMO

Nocardia is a potent bacterial producer of bioactive compounds. From a culture of Nocardia beijingensis NBRC 16342, we isolated four aromatic compounds, named beijinchromes A-D (1-4). We purified them by silica gel chromatography and reverse phase HPLC, and identified their structures by NMR and high resolution (HR)-MS analyses. 1, 2, and 4 are novel 1,2,3,8-tetrasubstituted naphthalenes, and 3 is a novel 3,8-disubstituted ortho-naphthoquinone. 1 and 2 exert antioxidant activities, and 3 exhibits antibiotic activity. Remarkably, the putative biosynthetic gene clusters for 1-4 are widely distributed in 37 Nocardia species, implying their potential to produce this family of compounds and important biological functions of beijinchromes.


Assuntos
Naftalenos/química , Naftoquinonas/química , Nocardia/química , Estrutura Molecular , Naftalenos/isolamento & purificação , Naftalenos/farmacologia , Naftoquinonas/isolamento & purificação , Naftoquinonas/farmacologia , Estereoisomerismo
16.
J Chromatogr A ; 1603: 160-164, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31272732

RESUMO

An environmentally benign and cost-effective method was designed for isolating and purifying condensed arenes from acetone-extractable portion (AEP) of a high-temperature coal tar through a high pressure preparative chromatograph (HPPC) with different packings, including silica gel, octadecyl silane, octyl bonded silica gel, and diol bonded silica gel. In total, 196 compounds were detected with a gas chromatograph/mass spectrometer from AEP and its eluates. From the eluates, naphthalene, anthracene, phenanthrene, fluoranthene, and pyrene were successfully isolated and purified, and their structures were confirmed by their 1H and 13C nuclear magnetic resonance spectra in addition to their mass spectra. Extraction-HPPC device and solvent recovery process were designed and developed, which can potentially be applied to industrial production because the process is easy-to-operate and ecofriendliness. In addition, the solvents used can be easily recovered and reused, and neither waste water nor other pollutions are emitted.


Assuntos
Alcatrão/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Temperatura Alta , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Pressão , Antracenos/isolamento & purificação , Fluorenos/isolamento & purificação , Naftalenos/isolamento & purificação , Fenantrenos/isolamento & purificação , Pirenos/isolamento & purificação
17.
Chin J Nat Med ; 17(5): 394-400, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-31171275

RESUMO

Six novel monacolin analogs, monacolins V1-V6 (1-6), together with seven known ones (7-13), were isolated from the ethyl acetate extract of red yeast rice. Their structures and absolute configurations were determined by spectroscopic methods, especially 2D NMR (1H-1HCOSY, HSQC, HMBC, and NOESY/ROESY) and CD spectroscopic analyses as well as chemical derivation. Monacolins V2 (2) and V3 (3) represent the first examples of monacolins with 3-hydroxybutyrate substitute. The anti-inflammatory inhibitory activities against the lipopolysaccharide (LPS) induced NO production in BV-2 cells as well as antioxidant activities against rat liver microsomal lipid peroxidation were evaluated.


Assuntos
Produtos Biológicos/química , Hidroxibutiratos/química , Naftalenos/química , Acetatos/química , Animais , Linhagem Celular Transformada , Hidroxibutiratos/isolamento & purificação , Hidroxibutiratos/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Estrutura Molecular , Naftalenos/isolamento & purificação , Naftalenos/farmacologia
18.
Chemosphere ; 229: 570-579, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31100628

RESUMO

Trace anionic dyes in wastewater are difficult to be rapidly and efficiently removed because they are completely soluble and poorly biodegradable. Herein, a facile and environmentally friendly adsorbent was fabricated via the surface functioned SiO2 with abundant amine groups of polyethyleneimine (PEI). The structural characterization indicated that PEI was successfully immobilized on the SiO2 surface. The adsorption performance of SiO2-PEI was evaluated using acid orange II (AOII) as model pollutant. The adsorption of AOII on SiO2-PEI displayed high removal rates in the pH range of 2.0-9.0, and exhibited ultrafast removal (99.1% removal rate at 10 min). The adsorption behavior fitted well with the Langmuir isotherm and pseudo-second-order kinetic model, and the maximum uptake capability of AOII was higher than 705.3 mg/g. The excellent adsorption capacity of AOII on SiO2-PEI mainly relied on the electrostatic attraction between the sulfonic acid group of AOII and amine group of PEI in the adsorption process. Additionally, other anionic dyes like acid fuchsin and direct sky blue 5B could also be fast and efficiently removed by SiO2-PEI. This work is expected to open new possibilities for the ultrafast removal of anionic dye pollutants.


Assuntos
Compostos Azo/isolamento & purificação , Corantes/isolamento & purificação , Nanopartículas/química , Naftalenos/isolamento & purificação , Polietilenoimina/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Ânions , Compostos Azo/química , Benzenossulfonatos/química , Benzenossulfonatos/isolamento & purificação , Corantes/química , Cinética , Microscopia Eletrônica de Varredura , Naftalenos/química , Dióxido de Silício/química , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Eliminação de Resíduos Líquidos/instrumentação , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Poluentes Químicos da Água/química , Difração de Raios X
19.
Sci Rep ; 9(1): 6429, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-31015563

RESUMO

Dittrichia viscosa (L.) Greuter, a perennial weed of the Mediterranean area, was reported to be source of active substances. Here, by means of both ingestion and contact assays, the biological activity of three different extracts (n-hexane, methanol, and distilled water) of D. viscosa aerial part has been evaluated against Sitophilus granarius (L.) adults, an important pest of stored grains. Ingestion assays showed negligible mortality and food deterrence for all the extracts, whereas only a slight reduction of some nutritional parameters (relative growth rate, relative consumption rate, food efficiency conversion) was recorded for water extract. High contact toxicity was found only for the n-hexane extract (24 h median lethal dose LD50 = 53.20 µg/adult). This extract was further subfractioned by silica gel column chromatography and then by thin layer chromatography. Further contact toxicity bioassays highlighted two active subfractions which were analyzed by GC-MS. This revealed the occurrence, in both subfractions, of two major peaks that were identified as α- and γ- costic acid isomers. Moreover, D. viscosa active subfractions, did not cause acetylcholinesterase (AChE) inhibition; therefore, in the light of progressive limitation of compounds acting by this mechanism of action, D. viscosa represents a promising eco-sustainable source of natural products for pest control.


Assuntos
Asteraceae/química , Produtos Biológicos/farmacologia , Inseticidas/farmacologia , Naftalenos/farmacologia , Gorgulhos/efeitos dos fármacos , Animais , Produtos Biológicos/isolamento & purificação , Relação Dose-Resposta a Droga , Grão Comestível/parasitologia , Cromatografia Gasosa-Espectrometria de Massas , Hexanos/química , Inseticidas/isolamento & purificação , Dose Letal Mediana , Longevidade/efeitos dos fármacos , Longevidade/fisiologia , Naftalenos/isolamento & purificação , Extratos Vegetais/química , Plantas Daninhas/química , Solventes/química , Gorgulhos/fisiologia
20.
Mar Drugs ; 17(4)2019 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-30987066

RESUMO

A study on the secondary metabolites of Aspergillus sp. XNM-4, which was derived from marine algae Leathesia nana (Chordariaceae), led to the identification of one previously undescribed (1) and seventeen known compounds (2-18). Their planar structures were established by extensive spectroscopic analyses, while the stereochemical assignments were defined by electronic circular dichroism (ECD) calculations. The biological activities of the compounds were assessed on five human cancer cell lines (PANC-1, A549, MDA-MB-231, Caco-2, and SK-OV-3), and one human normal cell line (HL-7702) using an MTT [3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl tetrazolium bromide] assay. Among them, the dimeric naphthopyrones 7, 10 and 12 exhibited potent cytotoxicity. Further mechanism studies showed that 12 induced apoptosis, arrested the cell cycle at the G0/G1 phase in the PANC-1 cells, caused morphological changes and generated ROS; and it induces PANC-1 cells apoptosis via ROS-mediated PI3K/Akt signaling pathway.


Assuntos
Antineoplásicos/farmacologia , Organismos Aquáticos , Aspergillus , Produtos Biológicos/farmacologia , Naftalenos/farmacologia , Pironas/farmacologia , Antineoplásicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Produtos Biológicos/isolamento & purificação , Linhagem Celular Tumoral , Descoberta de Drogas , Ensaios de Seleção de Medicamentos Antitumorais , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Humanos , Naftalenos/isolamento & purificação , Feófitas/microbiologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pironas/isolamento & purificação , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
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