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1.
Small ; : e2403606, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38940231

RESUMO

Salt deposition is a disturbing problem that limits the development of passive solar-driven interfacial evaporation. Inspired by the passive fluid control mechanism of the Tesla valve, a novel solar evaporator is proposed with a Tesla valve-like water transport structure to prevent salt accumulation at the evaporation interface. A unique "ion diode" salt resistance of this evaporator is significantly achieved by optimizing the two asymmetric water transport structures, consisting of one Tesla valve-like side and one wide-leg side, which establish a reverse-suppressing and forward-accelerating water transport channel. In contrast to the limited ion migration of the typical symmetric solar evaporator, such a channel caused by the water/salt ions transport difference between two water supply structures, reinforces the water/salt ions supply on the wide-leg side, thus leading to an apparent unidirectional salt ions migration from the wide-leg side to bulk water through the Tesla valve-like side. Consequently, an evaporation rate of 3.25 kg m-2 h-1 and a conversion efficiency of 83.27% under 2 suns are achieved in 16 wt% NaCl solution. The development of the Tesla Valve-like evaporator provides a new perspective for solving salt deposition and realizing scalable applications of solar-driven interfacial evaporation.

2.
Chemphyschem ; : e202400536, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38989542

RESUMO

The testing and evaluation of catalysts in CO2 electroreduction is a very tedious process. To study the catalytic system of CO2 reduction more quickly and efficiently, it is necessary to establish a method that can detect multiple catalysts at the same time. Herein, a series of CuBi bimetallic catalysts have been successfully prepared on a single glass carbon electrode by a scanning micropieptte contact method. The application of scanning electrochemical microscopy (SECM) enabled the visualization of the CO2 reduction activity in diverse catalyst micro-points. The SECM imaging with Substrate generation/tip collection (SG/TC) mode was conducted on CuBi bimetallic micro-points, revealing that HER reaction emerged as the prevailing reaction when a low overpotential was employed. While the applied potential was lower than -1.5 V (vs Ag/AgCl), the reduction of CO2 to formic acid became dominant. Increasing the bismuth proportion in the bimetallic catalyst can inhibit the hydrogen evolution reaction at low potential and enhances the selectivity of the CO product at high cathode overpotential.This research offers a novel approach to examining arrays of catalysts for CO2 reduction.

3.
Environ Res ; 245: 117985, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38123050

RESUMO

The global issue of ongoing trace metal emissions and legacy accumulation from diverse sources is posing threats to coastal wildlife. This study characterized the distribution of five metals in relation to dietary ecology (carbon and nitrogen stable isotopes: δ15N and δ13C) in representative predatory species (starfish, fish, and seabird) collected from the coast of Qingdao, northeastern China. Zinc (Zn) was the most abundant metal across species, followed by copper (Cu), chromium (Cr), cadmium (Cd), total and methylated mercury (THg and MeHg). Among the studied species, black-tailed gulls (Larus crassirostris) occupied the highest trophic position, followed by three predatory fish species, whereas the northern Pacific seastar (Asterias amurensis) had the lowest trophic position. The starfish exhibited high capacity to accumulate Cd, Cr and Cu. Conversely, black-tailed gulls exhibited high levels of Zn, while Hg was highest in predatory fishes. Across species, Cr, MeHg, THg and MeHg:THg showed significant positive correlations with δ13C, suggesting the influence of inshore food sources on their accumulation. Both MeHg and THg were significantly and positively correlated with δ15N, with MeHg demonstrating a greater slope, indicating their potential trophic magnification. We assessed health risks from the studied metals using established toxicity reference thresholds. Elevated risks of Hg were identified in three predatory fish species, while other metals and species remain within safe limits. These findings emphasize the significance of foraging patterns in influencing trace metal accumulation in coastal predators and highlight the importance of further monitoring.


Assuntos
Mercúrio , Oligoelementos , Poluentes Químicos da Água , Animais , Cádmio , Cadeia Alimentar , Monitoramento Ambiental , Mercúrio/análise , Metais/toxicidade , Isótopos de Nitrogênio , Zinco , Poluentes Químicos da Água/análise , Peixes
4.
Molecules ; 28(20)2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37894626

RESUMO

The very slow anodic oxygen evolution reaction (OER) greatly limits the development of large-scale hydrogen production via water electrolysis. By replacing OER with an easier urea oxidation reaction (UOR), developing an HER/UOR coupling electrolysis system for hydrogen production could save a significant amount of energy and money. An Al-doped cobalt ferrocyanide (Al-Co2Fe(CN)6) nanocube array was in situ grown on nickel foam (Al-Co2Fe(CN)6/NF). Due to the unique nanocube array structure and regulated electronic structure of Al-Co2Fe(CN)6, the as-prepared Al-Co2Fe(CN)6/NF electrode exhibited outstanding catalytic activities and long-term stability to both UOR and HER. The Al-Co2Fe(CN)6/NF electrode needed potentials of 0.169 V and 1.118 V (vs. a reversible hydrogen electrode) to drive 10 mA cm-2 for HER and UOR, respectively, in alkaline conditions. Applying the Al-Co2Fe(CN)6/NF to a whole-urea electrolysis system, 10 mA cm-2 was achieved at a cell voltage of 1.357 V, which saved 11.2% electricity energy compared to that of traditional water splitting. Density functional theory calculations demonstrated that the boosted UOR activity comes from Co sites with Al-doped electronic environments. This promoted and balanced the adsorption/desorption of the main intermediates in the UOR process. This work indicates that Co-based materials as efficient catalysts have great prospects for application in urea electrolysis systems and are expected to achieve low-cost and energy-saving H2 production.

5.
Mol Phylogenet Evol ; 157: 107037, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33278586

RESUMO

The purplish bifurcate mussel Mytilisepta virgata is widely distributed and represents one of the major components of the intertidal community in the northwestern Pacific (NWP). Here, we characterized population genetic structure of NWP populations throughout nearly their whole distribution range using both mitochondrial (mtDNA cox1) and nuclear (ITS1) markers. Population genetic analyses for mtDNA cox 1 sequences revealed two monophyletic lineages (i.e., southern and northern lineages) geographically distributed according to the two different surface water temperature zones in the NWP. The timing of the lineage split is estimated at the Pliocene- mid-Pleistocene (5.49-1.61 Mya), which is consistent with the timing of the historical isolation of the East Sea/Sea of Japan from the South and East China Seas due to sea level decline during glacial cycles. Historical sea level fluctuation during the Pliocene-Pleistocene and subsequent adaptation of mussels to different surface water temperature zones may have contributed to shaping the contemporary genetic diversity and deep divergence of the two mitochondrial lineages. In contrast to mtDNA sequences, a clear lineage split between the two mitochondrial lineages was not found in ITS1 sequences, which showed a star-like structure composed of a mixture of southern and northern mitochondrial lineages. Possible reasons for this type of mito-nuclear discordance include stochastic divergence in the coalescent processes of the two molecular markers, or balancing selection under different marine environments. Cryptic speciation cannot be ruled out from these results, and future work using genomic analyses is required to address whether the thermal physiology of these mussels corresponds to the deep divergence of their mitochondrial genes and to test for the existence of morphologically indistinguishable but genetically separate cryptic species.


Assuntos
Núcleo Celular/genética , Mitocôndrias/genética , Mytilidae/genética , Filogeografia , Animais , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Genes Mitocondriais , Variação Genética , Genética Populacional , Haplótipos/genética , Oceano Pacífico , Filogenia , Análise de Componente Principal , Fatores de Tempo
6.
Biochem Biophys Res Commun ; 529(1): 28-34, 2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32560815

RESUMO

The tripartite motif (TRIM) protein family are implicated in a wide array of cellular processes, including cell growth, differentiation, apoptosis and inflammation. This study aimed to investigate the specific function of TRIM59 in chondrocytes and its association with the pathophysiology of osteoarthritis (OA). We observed the downregulated TRIM59 expression in OA cartilage compared to normal tissues. Overexpression of TRIM59 suppressed interleukin 1 beta (IL-1ß)-induced extracellular matrix (ECM) metabolic imbalance, proinflammatory cytokine production, apoptosis and decrease in cell viability. Mechanistic analyses further revealed that IL-1ß-induced activation of the NF-κB and JAK2/STAT3 pathway is suppressed upon TRIM59 overexpression. TRIM59 expression was consistently decreased in a rat OA model in vivo, and its overexpression led to inhibition of matrix metallopeptidase-13 (MMP-13) production, proinflammatory cytokine levels and increased collagen type II (collagen II) and aggrecan synthesis. Our data collectively suggest that TRIM59 plays a critical in OA development through regulation of NF-κB and JAK2/STAT3 signaling pathway. Pharmacological upregulation of TRIM59 may therefore present an effective novel therapeutic approach for OA.


Assuntos
Interleucina-1beta/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Osteoartrite/metabolismo , Proteínas com Motivo Tripartido/metabolismo , Animais , Apoptose , Cartilagem/metabolismo , Cartilagem/patologia , Células Cultivadas , Condrócitos/metabolismo , Condrócitos/patologia , Modelos Animais de Doenças , Matriz Extracelular/metabolismo , Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Janus Quinase 2/metabolismo , Masculino , NF-kappa B/metabolismo , Osteoartrite/genética , Osteoartrite/patologia , Ratos , Ratos Sprague-Dawley , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Proteínas com Motivo Tripartido/genética
7.
J Nat Prod ; 82(7): 1759-1767, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31246464

RESUMO

Ten new iridal-type triterpenoid derivatives, polycycloiridals K-T (1-10), with a cyclopentane moiety originating from the cyclization of the homofarnesyl side chain were isolated from the rhizomes of Belamcanda chinensis. Their structures were established by spectroscopic data, a single-crystal X-ray diffraction analysis, TDDFT quantum mechanical calculations, and chemical derivatization. Compounds 2 and 10 exhibited 33.4% and 32.9% inhibitory activities, respectively, against PTP1b (protein tyrosine phosphatase) at a concentration of 10 µM. A putative biosynthetic pathway is proposed.


Assuntos
Ciclopentanos/química , Iridaceae/química , Rizoma/química , Triterpenos/isolamento & purificação , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Cristalografia por Raios X , Estrutura Molecular , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray , Triterpenos/química
8.
Bioorg Chem ; 83: 20-28, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30339861

RESUMO

Eight new iridal-type triterpenoid derivatives, including two noriridals with ether bridge (1-2); two iridals lactone (3-4), four monocyclic iridals (5-8), together with five known iridals (9-14) were identified from the rhizome of Belamcanda chinensis. Their structures were elucidated on the basis of comprehensive spectroscopic methods and electronic circular dichroism (ECD) calculations. Bioassay results showed that belamcanoxide B (1) exhibited moderated cytotoxic activities against HCT-116 and MCF-7 cell lines with IC50 values of 5.58 and 3.35 µM.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Iridaceae/química , Triterpenos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Triterpenos/química , Triterpenos/isolamento & purificação
9.
J Asian Nat Prod Res ; 21(9): 881-886, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30663896

RESUMO

Two new iridal-type triterpenoids, named forrestins A and B (1 and 2), were isolated from Iris forrestii Dykes by comprehensive chromatographic methods. The structures of 1 and 2 were elucidated by interpretation of extensive spectroscopic data including 1D and 2D NMR and HRESIMS.


Assuntos
Gênero Iris/química , Triterpenos/química , Estrutura Molecular
10.
J Org Chem ; 83(1): 167-173, 2018 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-29188714

RESUMO

Secoheliosphanes A (1) and B (2) and secoheliospholane A (3), possessing an unusual 7,8-seco-jatrophane skeleton and an unprecedented 9,10-seco-7,10-epoxyjatropholane skeleton, respectively, were isolated from the whole plants of Euphorbia helioscopia, along with two biogenetically precursors, a new jatrophane diterpene, 2-epi-euphornin I (4) and a known jatrophane diterpene, euphoscopin A (5). Structures of 1-4 including absolute configurations were elucidated on the basis of spectroscopic data, X-ray crystallography, and chemical conversion. Compounds 1 and 2 were prepared from 4 and 5, respectively, confirming their structural assignments. Notably, 1 and 2 presented the first examples of seco-jatrophane-type diterpenoids and 3 featured a novel 5/6/7/7-fused tetracyclic ring skeleton. Among them, compound 2 showed modest activity against HSV-1 with IC50 value of 6.41 µM.


Assuntos
Antivirais/farmacologia , Diterpenos/farmacologia , Euphorbia/química , Herpesvirus Humano 1/efeitos dos fármacos , Antivirais/química , Antivirais/isolamento & purificação , Cristalografia por Raios X , Diterpenos/química , Diterpenos/isolamento & purificação , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Modelos Moleculares , Conformação Molecular , Relação Estrutura-Atividade
11.
Org Biomol Chem ; 16(20): 3754-3759, 2018 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-29722783

RESUMO

Belamchinenin A (1), an unprecedented 6/5/6-fused tricyclic triterpenoid with a novel carbon skeleton, has been isolated from the rhizomes of Belamcanda chinensis. Compound 1 features a half-caged tricyclic nucleus with a flexible geranyl side chain. Its structure was determined by the interpretation of spectroscopic data. The absolute configuration of tricyclic nucleus system of 1 was unequivocally assigned by ECD calculation. Geometries optimization indicated that the tricyclic nucleus system is rigid. Compound 1 showed cytotoxic activities against five cells with IC50 values from 2.29 to 4.47 µM.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Gênero Iris/química , Triterpenos/química , Triterpenos/farmacologia , Linhagem Celular Tumoral , Humanos , Concentração Inibidora 50 , Modelos Moleculares , Conformação Molecular , Rizoma/química
12.
Phys Chem Chem Phys ; 20(48): 30351-30364, 2018 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-30488929

RESUMO

Two-dimensional (2D) transition metal dichalcogenides (TMDs) MX2 (M = Mo, W; X = S, Se, Te) possess unique properties and novel applications in optoelectronics, valleytronics and quantum computation. In this work, we performed first-principles calculations to investigate the electronic, optical and transport properties of the van der Waals (vdW) stacked MX2 heterostructures formed by two individual MX2 monolayers. We found that the so-called Anderson's rule can effectively classify the band structures of heterostructures into three types: straddling, staggered and broken gap. The broken gap is gapless, while the other two types possess direct (straddling, staggered) or indirect (staggered) band gaps. The indirect band gaps are formed by the relatively higher energy level of Te-d orbitals or the interlayer couplings of M or X atoms. For a large part of the formed MX2 heterostructures, the conduction band maximum (CBM) and valence band minimum (VBM) reside in two separate monolayers, thus the electron-hole pairs are spatially separated, which may lead to bound excitons with extended lifetimes. The carrier mobilities, which depend on three competitive factors, i.e. elastic modulus, effective mass and deformation potential constant, show larger values for electrons of MX2 heterostructures compared to their constituent monolayers. Finally, the calculated optical properties reveal strong absorption in the ultraviolet region.

13.
Mikrochim Acta ; 186(1): 24, 2018 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-30560307

RESUMO

Carbon dots codoped with magnesium and nitrogen (Mg,N-CDs) were synthesized via a one-step microwave-assisted method. They display blue fluorescence (with excitation/emission peaks at 380/460 nm and a 33% quantum yield) and possess high dispersity in aqueous solution. The fluorescence of the Mg,N-CDs is highly sensitive to paraoxon in the presence of pralidoxime (PAM) acting as the linking agent. Electron transfer from Mg,N-CDs to paraoxon in the presence of PAM leads to the fluorescence quenching of Mg,N-CDs. The concentration of paraoxon is determined by measuring the quenching efficiency of the Mg,N-CD-PAM assay system. Fluorescence drops with increasing concentrations of paraoxon in the 0.005-3.0 µM range, and the limit of detection is 0.87 nM. The method is highly selective for paraoxon even in the presence of possible interferences. Real sample study of tap and river water showed the assay to have good repeatability and accuracy. Graphical abstract Schematic diagram of magnesium and nitrogen co-doped carbon dots (Mg,N-CDs) as a fluorescent probe for paraoxon detection by using pralidoxime as a linker.

14.
Mol Ecol ; 26(18): 4591-4602, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28727261

RESUMO

The Yangtze (Changjiang) River enters the East China Sea with huge annual freshwater and sediment deposits. This outflow, known as the Changjiang diluted water (CDW), causes striking ecological gradients that potentially shape coastal species' distribution and differentiation. The CDW has long been rendered as a marine biogeographic boundary separating cold-temperature and warm-water faunas, but it remains unclear whether and to what extent it acts as an intraspecific barrier. Here, we synthesize published phylogeographic studies related to the CDW to address these issues. We find that the influence of the CDW on population differentiation is taxonomically variable, and even congeneric species may respond differently. In studies that claim the CDW is a phylogeographic barrier, the underlying assumptions explaining observed genetic breaks are sometimes incorrect, and some may have misinterpreted results due to conceptual confusion or insufficient geographic sampling. After excluding these studies, the remaining ones generally show shallow genetic divergence but significant population structure for coastal species across the CDW, suggesting that the CDW has not been a historically persistent barrier, but rather has acted as a filter within some species recently, probably after the last glacial maximum.


Assuntos
Ecossistema , Genética Populacional , Filogeografia , Rios , China , Ecologia
15.
Planta Med ; 82(7): 632-8, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26848706

RESUMO

Five new compounds, including a rare phenyldihydronaphthalene lignanamide (1), an unusual hybrid-norlignan derivative (2), a rare cycloheptenone oxide derivative (3), one new acorane-type sesquiterpenoid (4), and one new guaiane-type sesquiterpenoid (5), together with seven known compounds (6-12), have been isolated from the rhizomes of Acorus tatarinowii. The structures of compounds 1-5 were determined by means of extensive spectroscopic methods. To the best of our knowledge, this is first report of a phenyldihydronaphthalene lignanamide and hybrid-norlignan and cycloheptenone oxide derivatives from the genus Acorus. In addition, compound 5 represents the first guaiane-type sesquiterpenoid with an epoxy group located between C-6 and C-9 from natural sources. Compounds 1-12 were evaluated for their in vitro cytotoxicity against five tumor cell lines. Among them, 2, 3, 5, and 10 exhibited moderate cytotoxicity with IC50 values of 2.11-9.23 µM.


Assuntos
Acorus/química , Antineoplásicos Fitogênicos/isolamento & purificação , Lignanas/isolamento & purificação , Sesquiterpenos/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Lignanas/química , Lignanas/farmacologia , Estrutura Molecular , Rizoma/química , Sesquiterpenos/química , Sesquiterpenos/farmacologia
16.
J Asian Nat Prod Res ; 18(10): 921-7, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27310650

RESUMO

Phytochemical investigation on the whole plants of Iris japonica led to the isolation of four new aromatic glycosides. Their structures including the absolute configurations were determined by spectroscopic and chemical methods as (-)-4-hydroxy-3-methoxy acetophenone 4-O-ß-d-{6-O-[4-O-(7R,8S)-(4-hydroxy-3-methoxyphenylglycerol-8-yl)-3-methoxybenzoyl]}-glucopyranoside (1), (-)-4-hydroxy-3-methoxy acetophenone 4-O-ß-d-{6-O-[4-O-(7S,8R)-(4-hydroxy-3-methoxyphenylglycerol-8-yl)-3-methoxybenzoyl]}-glucopyranoside (2), (-)-4-hydroxy-3-methoxy acetophenone 4-O-ß-d-{6-O-[4-O-(7R,8R)-(4-hydroxy-3-methoxyphenylglycerol-8-yl)-3-methoxybenzoyl]}-glucopyranoside (3), (-)-4-hydroxy-3-methoxy acetophenone 4-O-ß-d-{6-O-[4-O-(7S,8S)-(4-hydroxy-3-methoxyphenylglycerol-8-yl)-3-methoxybenzoyl]}-glucopyranoside (4), respectively.


Assuntos
Medicamentos de Ervas Chinesas/isolamento & purificação , Glicosídeos/isolamento & purificação , Gênero Iris/química , Acetofenonas/química , Medicamentos de Ervas Chinesas/química , Glicosídeos/química , Estrutura Molecular , Estereoisomerismo
17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(9): 2846-51, 2016 Sep.
Artigo em Zh | MEDLINE | ID: mdl-30084613

RESUMO

Compared with traditional quantum dots, carbon quantum dots (CQDs) have aroused tremendous research interest among scientists as new fluorescent carbon nanomaterials due to their unique properties (easy surface functionalization, good biocompatibility, and low toxicity). The nitrogen-doped carbon quantum dots (NCDs) was synthesized with one-step hydrothermal treatment with citric acid as carbon source, and ammonia as nitrogen source. The obtained NCDs exhibited excellent water-solubility and high stability. High-resolution Transmission electron microscopy (HRTEM) image showed that the diameter of particles was about 3nm. Fourier transform infrared (FIIR) and X-ray photoelectron spectroscopy (XPS) spectra analysis demonstrated that the NCDs are functionalized with hydroxyl, amino, carbonyl, and carboxylic acid groups, which indicated NCDs has better water-solubility. It was further demonstrated that such NCDs can serve as effective fluorescent sensing platform for Hg2+ ions detection with sensitivity and selectivity. In a PBS butter solution (0.1 mol·L-1 pH 7.0), the fluorescence quenching ratio (F/F0) indicated linear responses with Hg2+ concentration ranging from 0.001 to 0.1 µmol·L-1, with the detection limit of 2.1 nmol·L-1. The fluorescence technique was superior in terms of sensitivity, selectivity and simplicity. It was successfully applied to determination of Hg2+ in samples.

18.
J Nat Prod ; 78(4): 754-61, 2015 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-25781655

RESUMO

Seven new limonoids, dysomollides A-G (1-7), and two new cycloapotirucallane-type triterpenoids, dysomollins A and B (8 and 9), together with three known compounds, dysoxylumin A (10) and toonapubesins A (11) and B (12), were isolated from the twigs of Dysoxylum mollissimum var. glaberrimum. The structures of 1-9 were elucidated on the basis of spectroscopic methods. Compound 10 showed inhibitory activity against A549 cells with an IC50 value of 2.1 µM, and compound 11 exhibited activity against P388 cells with an IC50 value of 6.7 µM.


Assuntos
Medicamentos de Ervas Chinesas/isolamento & purificação , Limoninas/isolamento & purificação , Meliaceae/química , Triterpenos/isolamento & purificação , Animais , Antineoplásicos Fitogênicos/química , Doxorrubicina/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Células HL-60 , Humanos , Concentração Inibidora 50 , Leucemia P388 , Limoninas/química , Limoninas/farmacologia , Estrutura Molecular , Triterpenos/química , Triterpenos/farmacologia
19.
Planta Med ; 81(3): 247-56, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25679147

RESUMO

Six new taccalonolides, taccalonolides AT-AY (1-6), and two new withanolides, chantriolides D and E (7 and 8), together with ten known compounds (9-18), have been isolated from whole plants of Tacca chantrieri. The structures, including the absolute configurations of some of the compounds, were determined by spectroscopic and chemical methods. All compounds were evaluated for their in vitro cytotoxicity against five tumor cell lines. Compounds 9, 10, 13-15, and 17 exhibited cytotoxic activity, with IC50 values of 1.13-5.71 µM, while compound 7 showed selective cytotoxicity. The results indicated that taccalonolides with a six-membered lactone moiety located at C-15 and C-24 were devoid of cytotoxicity against five tumor cell lines (> 10 µM).


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Dioscoreaceae/química , Esteroides/isolamento & purificação , Vitanolídeos/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Células HCT116 , Células Hep G2 , Humanos , Estrutura Molecular , Neoplasias/tratamento farmacológico , Fitoterapia , Esteroides/química , Esteroides/farmacologia , Esteroides/uso terapêutico , Vitanolídeos/química , Vitanolídeos/farmacologia , Vitanolídeos/uso terapêutico
20.
J Asian Nat Prod Res ; 17(5): 423-9, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25966607

RESUMO

An unusual 5-C-methylated-dihydrobenzofuroisocoumarin, named multifidarin A (1), and two new ent-kaurane diterpenoids, named multikauranes A (2) and B (3), together with three known ent-kaurane diterpenoids, were isolated from the whole plants of Pteris multifida. The structures of 1-3 were elucidated by spectroscopic methods. The cytotoxic activities of all new compounds were evaluated against five human tumor cell lines. A possible biosynthetic process for the formation of 1 is proposed.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Cumarínicos/isolamento & purificação , Diterpenos do Tipo Caurano/isolamento & purificação , Medicamentos de Ervas Chinesas/isolamento & purificação , Pteris/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Cumarínicos/química , Cumarínicos/farmacologia , Diterpenos do Tipo Caurano/química , Diterpenos do Tipo Caurano/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Humanos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular
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