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1.
J Agric Food Chem ; 68(1): 17-32, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31809036

RESUMO

Weeds had caused significant loss for crop production in the process of agriculture. Herbicides have played an important role in securing crop production. However, the high reliance on herbicides has led to environmental issues as well as the evolution of herbicide resistance. Thus, there is an urgent need for new herbicides with safer toxicological profiles and novel modes of action. Actinomycetes produce very diverse bioactive compounds, of which some show potent biopesticidal activity. The herbicidal secondary metabolites from actinomycetes can be classified into several groups, such as amino acids, peptides, nucleosides, macrolides, lactones, amide, amines, etc., some of which have been successfully developed as commercial herbicides. The structure diversity and evolved biological activity of secondary metabolites from actinomycetes can offer opportunities for the development of both directly used bioherbicides and synthetic herbicides with new target sites, and thus, this review focuses on the structure, herbicidal activity, and modes of action of secondary metabolites from actinomycetes.


Assuntos
Actinobacteria/química , Herbicidas/química , Herbicidas/farmacologia , Actinobacteria/metabolismo , Descoberta de Drogas , Herbicidas/metabolismo , Plantas Daninhas/efeitos dos fármacos , Plantas Daninhas/crescimento & desenvolvimento , Metabolismo Secundário , Controle de Plantas Daninhas
2.
J Enzyme Inhib Med Chem ; 34(1): 1607-1614, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31474167

RESUMO

Steroids are classes of natural products widely distributed in nature, which have been demonstrated to exhibit broad biological functions, and have also attracted increasing interest from bioorganic and pharmaceutical researches. In order to develop novel chemical entities as potential cytotoxic agents, a series of steroidal isatin conjugations derived from epiandrosterone and androsterone were efficiently prepared and characterized, and all these obtained compounds were screened for their potential cytotoxic activities. The preliminary bioassay indicated that most of the newly synthesized compounds exhibited good cytotoxic activities against human gastric cancer (SGC-7901), melanoma (A875), and hepatocellular liver carcinoma (HepG2) cell lines compared with 5-fluorouracil (5-FU), which might be considered as promising scaffold for further development of potential anticancer agents.


Assuntos
Androsterona/química , Antineoplásicos Fitogênicos/farmacologia , Produtos Biológicos/farmacologia , Isatina/farmacologia , Esteroides/farmacologia , Androsterona/análogos & derivados , Antineoplásicos Fitogênicos/síntese química , Antineoplásicos Fitogênicos/química , Produtos Biológicos/síntese química , Produtos Biológicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Isatina/síntese química , Isatina/química , Estrutura Molecular , Esteroides/síntese química , Esteroides/química , Relação Estrutura-Atividade
3.
Org Biomol Chem ; 17(14): 3635-3639, 2019 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-30916700

RESUMO

Oxazoles are an important class of biologically active metabolites from nature, and exhibit broad biological activities as the lead for drug discovery. Hinduchelins are a class of unusual natural products with an oxazole unit, isolated from Streptoalloteichus hindustanus, and with a potential iron-chelating ability. These compounds are the first identified naturally occurring unusual oxazole derivatives to possess a catechol unit. However, some of these compounds are not abundant in nature, and thus, the efficient syntheses of these compounds are advantageous in exploring their potential applications. This paper reports the efficient synthesis and bio-evaluation of hinduchelins A-D and their derivatives with convenient procedures and high yields.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Antineoplásicos/farmacologia , Produtos Biológicos/farmacologia , Inseticidas/farmacologia , Oxazóis/farmacologia , Actinomycetales/química , Animais , Antibacterianos/síntese química , Antibacterianos/química , Antifúngicos/síntese química , Antifúngicos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Afídeos/efeitos dos fármacos , Produtos Biológicos/síntese química , Produtos Biológicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Fungos/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Inseticidas/síntese química , Inseticidas/química , Testes de Sensibilidade Microbiana , Mariposas , Oxazóis/síntese química , Oxazóis/química
4.
Future Med Chem ; 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30499701

RESUMO

AIM: Many heterocyclic compounds derived from natural steroids exhibited broad activities, so this work focused on the investigations on a series of steroidal thiazoline conjugates as antiviral agents. MATERIALS & METHODS:  A series of steroid derivatives containing thiazoline heterocycles were designed and synthesized via a convenient condensation procedure. The compounds were screened for their potential antivirus activities against Enterovirus 71 (EV71) and Coxsackie Virus Type B (CVB3). RESULTS AND CONCLUSION: The in vitro bioassay indicated that compounds 5b, 5g and 5i exhibited excellent antiviral effects on EV71, and compounds 5b, 5e, 6c and 6g presented better antiviral activities against CVB3 compared with the controls ribavirin or pirodavir. These results indicate that these steroidal thiazoline conjugates might be feasible therapeutic candidates against EV71 infection, which might also be considered as promising compounds for optimization of potential antivirus agents.

5.
J Cell Biochem ; 119(11): 9090-9098, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29953672

RESUMO

Forkhead box M1 (FOXM1) was initially identified as an oncogenic transcription factor, and multiple lines of evidence have demonstrated that FOXM1 is abundantly expressed and plays an irreplaceable role in several types of human cancers. Also, evidence has shown the association of FOXM1 with gastric carcinoma metastasis and patients prognosis; however, the potential role and molecular mechanism of FOXM1 in gastric cancer cell apoptosis are still obscure. The current study indicates that FOXM1 is highly expressed in a variety of gastric carcinoma cell lines, such as BGC823, MGC803, AGS, and SGC-7901, compared with the normal gastric mucosal epithelial cell lines CES-1. FOXM1 silence markedly inhibits AGS and SGC-7901 cell survival and proliferation, increases their apoptosis, and modulates apoptosis-related protein expression, including reduced Bcl-2 level and increased Bax and caspase-3 levels. Further study showed that FOXM1 depletion induced cell autophagy through increasing the level of beclin-1 and decreasing the P62 expression. We next corroborated that FOXM1 silence abolished the expression of Sirtuin 7 (SIRT7) and increased the level of insulin-like growth factor 2 (IGF2) and mammalian target of rapamycin (mTOR). Finally, our data documented that the SIRT7/mTOR/IGF2 pathway was involved in the function of FOXM1 in AGS cell growth and apoptosis. In conclusion, these results confirmed that FOXM1 is involved in gastric carcinoma progression via the SIRT7/mTOR/IGF2 pathway.


Assuntos
Proteína Forkhead Box M1/metabolismo , Fator de Crescimento Insulin-Like II/metabolismo , Sirtuínas/metabolismo , Neoplasias Gástricas/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Apoptose/genética , Apoptose/fisiologia , Autofagia/genética , Autofagia/fisiologia , Caspase 3/genética , Caspase 3/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Sobrevivência Celular/fisiologia , Proteína Forkhead Box M1/genética , Regulação Neoplásica da Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Fator de Crescimento Insulin-Like II/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sirtuínas/genética , Neoplasias Gástricas/genética , Serina-Treonina Quinases TOR/genética
6.
Nat Prod Res ; 32(4): 412-417, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28441878

RESUMO

Further chemical study of secondary metabolites from the soil actinomycete Streptomyces sp. WS-13394 resulted in the isolation of four new alkylated anthraquinone analogues (5-8). Their structures were elucidated on the basis of extensive spectroscopic analysis, including HR-ESI-MS, 1D and 2D NMR. The new compounds, together with analogues obtained before (1-4), were tested for their in vitro cytotoxicity against Huh-7 and SGC-7901.


Assuntos
Antraquinonas/química , Antraquinonas/farmacologia , Antineoplásicos/farmacologia , Streptomyces/química , Alquilação , Antineoplásicos/química , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Microbiologia do Solo , Espectrometria de Massas por Ionização por Electrospray , Relação Estrutura-Atividade
7.
ACS Appl Mater Interfaces ; 9(24): 20671-20678, 2017 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-28569064

RESUMO

Full-color visible emissions are particularly crucial for applications in displays and lightings. In this work, we developed a facile room-temperature ligand-assisted supersaturated recrystallization synthesis of monodisperse, cubic structure Cs1-mFAmPbX3 (X = Cl, Br, and I or their mixtures Cl/Br and Br/I, 0 ≤ m ≤ 1) hybrid perovskite quantum dots (QDs). Impressively, cation substitution of Cs+ by FA+ was beneficial in finely tuning the band gap and in exciton recombination kinetics, improving the structural stability, and raising the absolute quantum yields up to 85%. With further assistance of anion replacement, full-spectral visible emissions in the wavelength range of 450-750 nm; narrow full width at half-maxima, and a wide color gamut, encompassing 130% of National Television System Committee television color standard, were achieved. Finally, Cs1-mFAmPbX3-polymer films retaining multicolor luminescence are prepared and a prototype white light-emitting diode device was constructed using green Cs0.1FA0.9PbBr3 and red Cs0.1FA0.9Br1.5I1.5 QDs as color converters, certainly suggesting their potential applications in the optoelectronics field.

8.
Anal Chem ; 88(7): 4099-106, 2016 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-26937775

RESUMO

A strategy to achieve high sensitivity of noncontact optical thermometer via the structure design of nanoglass-ceramic and the usage of Ln(3+) (Ln = Eu, Tb, Dy) luminescence as reference signal and Cr(3+) emission as temperature signal was provided. Specifically, the synthesized dual-phase glass-ceramics were evidenced to enable spatially confined doping of Ln(3+) in the hexagonal GdF3 nanocrystals and Cr(3+) in the cubic Ga2O3 nanoparticles, being beneficial to suppressing detrimental energy transfer between Ln(3+) and Cr(3+) and thus significantly enhancing their luminescence. As a consequence, completely different temperature-sensitive luminescence of Ln(3+)4f → 4f transition and Cr(3+) 3d → 3d transition in the present glass-ceramic resulted in obvious variation of Cr(3+)/Ln(3+) fluorescence intensity ratio with temperature and strikingly high detecting temperature sensitivity of 15-22% per K. We believe that this preliminary study will provide an important advance in exploring other innovative optical thermometry.

9.
Dalton Trans ; 45(11): 4762-70, 2016 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-26862714

RESUMO

With an increasing demand for high-power warm white light emitting diodes (w-LEDs), the discovery of efficient red-emitting inorganic color converters is in great demand. Herein, a novel perovskite La0.5Na0.5TiO3:Eu(3+) red-emitting phosphor with excellent thermal stability and high quantum efficiency has been successfully synthesized by a traditional solid-state reaction. Then, the developed La0.5Na0.5TiO3:Eu(3+) red phosphor and commercial YAG:Ce(3+) yellow phosphor were incorporated into an innovatively designed low-melting glass. Impressively, the destruction of La0.5Na0.5TiO3:Eu(3+) and YAG:Ce(3+) phosphor particles during glass melting was quite low. Remarkably, the fabricated w-LEDs using an InGaN-based blue chip combined with Phosphor in Glass (PiG) plates exhibited an improved chromaticity feature and superior optical performance. Through simply adjusting the content of red phosphors in the PiG, the correlated color temperature of the PiG-based w-LEDs evolved from cool white (6771 K) to warm white (4417 K) and the color rendering index increased from 73.4 to 86.4. Moreover, the PiG-based warm w-LEDs presented superior thermal stability.

10.
ACS Appl Mater Interfaces ; 7(34): 19484-93, 2015 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-26287513

RESUMO

Yb(3+)/Er(3+)/Cr(3+) triply doped transparent bulk glass ceramic containing orthorhombic YF3 and cubic Ga2O3 nanocrystals was fabricated by a melt-quenching route to explore its possible application in optical thermometry with high spatial and temperature resolution. It was experimentally observed that Yb(3+)/Er(3+) ions incorporated into the precipitated YF3 nanophase, while Cr(3+) ions partitioned into the crystallized Ga2O3 nanophase after glass crystallization. Importantly, such spatial isolation strategy efficiently suppressed adverse energy transfer among different active ions. As a consequence, intense green anti-Stokes luminescence originated from Er(3+): (2)H11/2,(4)S3/2 → (4)I15/2 transitions, and deep-red Stokes luminescence transitions assigned to Cr(3+): (2)E → (4)A2 radiation were simultaneously realized. Impressively, the intermediate crystal-field environment for Cr(3+) in Ga2O3 made it possible for lifetime-based temperature sensing owing to the competition of radiation transitions from the thermally coupled Cr(3+) (2)E and (4)T2 excited states. In the meantime, the low-phonon-energy environment for Er(3+) in YF3 was beneficial for upconversion fluorescence intensity ratio-based temperature sensing via thermal population between the (2)H11/2 state and (4)S3/2 state. The Boltzmann distribution theory and the two-level kinetic model were adopted to interpret these temperature-dependent luminescence of Er(3+) and Cr(3+), respectively, which gave the highest temperature sensitivities of 0.25% K(-1) at 514 K for Er(3+) and 0.59% K(-1) at 386 K for Cr(3+).

11.
Opt Lett ; 40(15): 3607-10, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26258369

RESUMO

Transparent bulk glass ceramic containing Cr3+:LiGa5O8 nanoparticles was fabricated as an alternative for monocrystal to explore the possible application in fluorescence lifetime-based temperature sensing. Such glass ceramic exhibited deep-red luminescence upon the excitation of the wide wavelength range of visible light. Impressively, the Cr3+ lifetime dramatically decreased from 2.45 to 0.22 ms with the temperature increasing from 293 to 563 K, owing to the competition of radiation transitions from the thermally coupled 2E and 4T2 excited states. A two-level kinetic model was adopted to interpret this temperature-dependent luminescence of Cr3+, which gave a highest temperature sensitivity of 1.15% K(-1).

12.
Dalton Trans ; 44(12): 5288-93, 2015 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-25708129

RESUMO

Yb(3+)/Ho(3+) activated glass ceramics containing ß-YF3 nanocrystals were successfully fabricated. The green ((5)S2/(5)F4→(5)I8) upconversion emission is dominant in the glass ceramics and is about 160 times stronger than that of the precursor glass, resulting from the partition of lanthanide activators into a low-phonon-energy crystalline lattice and the subsequent low probability of multi-phonon nonradiative relaxation from the (5)S2/(5)F4 and (5)I6 states to the lower ones. Upon the introduction of Ce(3+) ions into nano-glass-ceramics, two efficient cross-relaxation processes between Ho(3+) and Ce(3+), i.e., Ho(3+):(5)S2/(5)F4 + Ce(3+):(2)F5/2→Ho(3+):(5)F5 + Ce(3+):(2)F7/2 and Ho(3+):(5)I6 + Ce(3+):(2)F5/2→Ho(3+):(5)I7 + Ce(3+):(2)F7/2, are demonstrated to greatly suppress the population of the green-emitting (5)S2/(5)F4 state and to enhance the population of the red-emitting (5)F5 one, leading to the intense single-band red UC radiation of Ho(3+).

13.
Phys Chem Chem Phys ; 17(11): 7100-3, 2015 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-25697224

RESUMO

K(Y1-xYbx)3F10 (x = 0-1) solid-solution nanocrystals embedded glass ceramics were fabricated via glass self-crystallization. Using Eu(3+) as a structural probe, the partition of lanthanide activators into the K(Y1-xYbx)3F10 lattice was evidenced. As a consequence, color-tunable upconversion luminescence from green to red was easily realized by modifying Yb(3+) content in the Er(3+)-doped nano-glass-ceramics.

14.
J Antibiot (Tokyo) ; 68(3): 185-90, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25204346

RESUMO

Two new 32-membered macrolide compounds, named Novonestmycins A (1) and B (2), were isolated from the soil strain Streptomyces phytohabitans HBERC-20821. Their structures were elucidated by using spectroscopic methods, including 1D, 2D-NMR and MS spectrometry. The two compounds showed strong activities against the phytophathogenic fungi Corynespora cassiicola, Rhizoctonia solani and Septoria nodorum, with MIC values of 0.78, 0.39 and 0.78 µg ml(-1), respectively. In addition, the two compounds exhibited potent inhibitory activities against four different human tumor cell lines as well as one 5-FU-resistant human hepatocellular carcinoma cell line, with IC50 of 0.15-0.48 µg ml(-1) and 0.24-1.34 µg ml(-1), respectively.


Assuntos
Antibacterianos/isolamento & purificação , Macrolídeos/isolamento & purificação , Microbiologia do Solo , Antibacterianos/química , Antibacterianos/farmacologia , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/isolamento & purificação , Antibióticos Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Humanos , Macrolídeos/química , Macrolídeos/farmacologia , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Streptomyces/metabolismo
15.
Virol J ; 11: 195, 2014 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-25410379

RESUMO

BACKGROUND: The pimprinine family of compounds represent very important and promising microbial metabolites for drug discovery. However, their ability in inhibiting viral infections has not yet been tested. METHODS: The antiviral activity of the pimprinine family of compounds was evaluated by determining the cytopathic effect (CPE), cell viability or plaque-forming unit (PFU), and virus yield. The mechanism of action against EV71 was determined from the virucidal activity, and effective stage and time-of-addition assays. The effects on EV71 replication were evaluated further by determining viral RNA synthesis, protein expression and cells apoptosis using the SYBR Green assays, immunofluorescence assays and flow cytometric assays, respectively. RESULTS: Pimprinethine, WS-30581 A and WS-30581 B inhibited EV71-induced CPE, reduced progeny EV71 yields, as well as prevented EV71-induced apoptosis in human rhabdomyosarcoma (RD) cells. These compounds were found to target the early stages of the EV71 replication in cells including viral RNA replication and protein synthesis. They also showed antiviral activity against ADV-7, and were slightly active against CVB3, HSV-1 and H1N1 with a few exceptions. Pimprinine was slightly active or inactive against all the viruses tested. The mechanisms by which these compounds act against the viruses tested may be similar to that demonstrated for EV71. CONCLUSION: The data described herein demonstrate that the pimprinine family of compounds are inhibitors effective against the replication of EV71 and ADV-7, so they might be feasible therapeutic agents for the treatment of viral infections.


Assuntos
Antivirais/farmacologia , Enterovirus Humano A/efeitos dos fármacos , Enterovirus Humano A/fisiologia , Oxazóis/farmacologia , Adenoviridae/efeitos dos fármacos , Adenoviridae/fisiologia , Antivirais/isolamento & purificação , Efeito Citopatogênico Viral/efeitos dos fármacos , Herpesvirus Humano 1 , Viabilidade Microbiana/efeitos dos fármacos , Oxazóis/isolamento & purificação , Streptomyces/química , Ensaio de Placa Viral , Replicação Viral/efeitos dos fármacos
16.
Stand Genomic Sci ; 9(3): 775-82, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25197462

RESUMO

Bacillus amyloliquefaciens HB-26, a Gram-positive bacterium was isolated from soil in China. SDS-PAGE analysis showed this strain secreted six major protein bands of 65, 60, 55, 34, 25 and 20 kDa. A bioassay of this strain reveals that it shows specific activity against P. brassicae and nematode. Here we describe the features of this organism, together with the draft genome sequence and annotation. The 3,989,358 bp long genome (39 contigs) contains 4,001 protein-coding genes and 80 RNA genes.

17.
Genome Announc ; 2(3)2014 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-24855295

RESUMO

Bacillus thuringiensis NBIN-866, a Gram-positive bacterium, was isolated from soil in China. We announce here the draft genome sequence of strain B. thuringiensis NBIN-866, which possesses highly nematocidal factors, such as proteins and small molecular peptides.

18.
Chem Pharm Bull (Tokyo) ; 62(1): 118-21, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24390501

RESUMO

Four new alkylated anthraquinone analogues (1-4) were isolated from a soil actimomycete Streptomyces sp. WS-13394. The structures of compounds 1-4 were elucidated to be 1,4,6-trihydroxy-8-alkylanthraquinones by means of spectroscopic methods, including UV, one dimensional (1D), 2D-NMR and MS spectrometry. All compounds showed activities against BGC-823 and MCF-7 with IC50 from 0.99 to 3.54 µg/mL, while 2 exhibited cytotoxicity against HepG2, A875, BGC-823 and MCF-7 with IC50 2.29, 4.90, 0.99, and 1.66 µg/mL, respectively.


Assuntos
Actinobacteria/química , Antraquinonas/química , Antraquinonas/farmacologia , Solo/química , Streptomyces/química , Alquilação , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Células Hep G2 , Humanos , Concentração Inibidora 50 , Células MCF-7
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