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1.
Nat Prod Res ; 35(19): 3346-3349, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34590506

RESUMO

One new diarylpentanone, 4(S)-hydroxy-1, 5-diphenyl -2(E)-en-1-pentanone (1), two diarylpentanones isolated from Wikstroemia indica for the first time (3 and 5) and two other known diarylpentanones were isolated from petroleum ether fraction of root of Wikstroemia indica. The structure of the new compound including absolute configuration was elucidated by extensive spectroscopic techniques, including 1D, 2D NMR, HR-ESI-MS and ECD spectroscopy. All isolated compounds were tested for their cytotoxic activity against cancer-derived cell lines A549. Compound 5 exhibited remarkable cytotoxic activity comparable to that of positive control cisplatin.


Assuntos
Antineoplásicos Fitogênicos , Pentanonas/farmacologia , Wikstroemia , Células A549 , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Pentanonas/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Raízes de Plantas/química , Wikstroemia/química
2.
Molecules ; 26(15)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34361724

RESUMO

Orchids are rich treasure troves of various important phytomolecules. Among the various medicinal orchids, Ansellia africana stands out prominently in the preparing of various herbal medicines due to its high therapeutic importance. The nodal explants of A. africana were sampled from asymbiotically germinated seedlings on basal Murashige and Skoog (MS) medium and were micropropagated in MS medium supplemented with 3% sucrose and 10 µM meta topolin (mT) + 5 µM naphthalene acetic acid (NAA) +15 µM indole butyric acid (IBA) + 30 µM phloroglucinol (PG). In the present study, the essential oil was extracted by hydrodistillation and the oleoresins by the solvent extraction method from the micropropagated A. africana. The essential oil and the oleoresins were analysed by Gas Chromatography (GC) and GC/MS (Mass spectrometry). A total of 84 compounds were identified. The most predominant components among them were linoleic acid (18.42%), l-ascorbyl 2,6-dipalmitate (11.50%), linolenic acid (10.98%) and p-cresol (9.99%) in the essential oil; and eicosane (26.34%), n-butyl acetate (21.13%), heptadecane (16.48%) and 2-pentanone, 4-hydroxy-4-methyl (11.13%) were detected in the acetone extract; heptadecane (9.40%), heneicosane (9.45%), eicosane (6.40%), n-butyl acetate (14.34%) and styrene (22.20%) were identified and quantified in the ethyl acetate extract. The cytotoxic activity of essential oil and oleoresins of micropropagated A. africana was evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium Bromide) assay on Vero cells compared to the standard drug doxorubicin chloride. The present research contains primary information about the therapeutic utility of the essential oil and oleoresins of A. africana with a promising future research potential of qualitative and quantitative improvement through synchronised use of biotechnological techniques.


Assuntos
Citotoxinas/isolamento & purificação , Óleos Voláteis/isolamento & purificação , Orchidaceae/química , Extratos Vegetais/isolamento & purificação , Plântula/química , Acrilatos/isolamento & purificação , Alcanos/isolamento & purificação , Animais , Ácido Ascórbico/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Cresóis/isolamento & purificação , Meios de Cultura/química , Meios de Cultura/farmacologia , Citotoxinas/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Hidroponia/métodos , Ácido Linoleico/isolamento & purificação , Extração Líquido-Líquido/métodos , Óleos Voláteis/farmacologia , Orchidaceae/metabolismo , Palmitatos/isolamento & purificação , Pentanóis/isolamento & purificação , Pentanonas/isolamento & purificação , Extratos Vegetais/farmacologia , Plantas Medicinais , Plântula/metabolismo , África do Sul , Estireno/isolamento & purificação , Células Vero , Ácido alfa-Linolênico/isolamento & purificação
3.
Nat Prod Res ; 35(19): 3204-3209, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31711315

RESUMO

A new phenylpentenol, wortmannine H (1) was isolated from Talaromyces wortmannii LGT-4, an endophytic fungus of Tripterygium wilfordii. The structure of 1 was elucidated by IR, MS, 1D and 2D NMR spectra and comparison of the experimental and calculated optical rotatory dispersion (ORD). Monoamine oxidase (MAO), acetylcholinesterase (AChE) and phosphoinositide 3-kinase (PI3Kα) inhibitory activities of 1 was also tested. The compound did not show good biological activity.


Assuntos
Pentanonas/química , Talaromyces , Acetilcolinesterase , Endófitos , Estrutura Molecular , Monoaminoxidase , Pentanonas/isolamento & purificação , Fosfatidilinositol 3-Quinases , Talaromyces/química
4.
Food Chem ; 317: 126466, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32114273

RESUMO

Despite the literature comprises numerous studies dealing with the analysis of wort and beer flavour-related compounds by HS-SPME followed by GC-MS quantification, no generalized consensus exists regarding the optimal conditions for the extraction procedure. The complex chemistry nature of these matrices, the number of analytes, as well as the number and interactions among parameters affecting the extraction performance, requires the adoption of optimal experimental design protocols. This aspect is often overlooked and often not properly addressed in practice. Therefore, in the present work, the optimal conditions under which a range of wort and beer analytes can be extracted and quantified were analysed. The optimal extraction conditions were presented at two levels of aggregation: global (untargeted) and key-flavour analysis. Experimental data was generated by Definitive-Screening-Design, followed by model development and optimization. Both approaches were compared and critically analysed. For vicinal-diketones group, a complete validation study for the optimal conditions is presented.


Assuntos
Cerveja/análise , Análise de Alimentos/métodos , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/análise , Diacetil/análise , Diacetil/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cetonas/análise , Pentanonas/análise , Pentanonas/isolamento & purificação , Reprodutibilidade dos Testes , Paladar , Compostos Orgânicos Voláteis/isolamento & purificação
5.
J Hazard Mater ; 380: 120868, 2019 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-31319332

RESUMO

In this study, a novel thermo stable biosurfactants, 1-Pentanonacontene (C95H190) a fatty alkene and 3-Hydroxy-16-methylheptadecanoic acid (C18H36O3) were isolated from a marine isolate SGD-AC-13. Biosurfactants were produced using 1% yeast extract in tap water as production medium at 24 h in flask and 12 h in bioreactor. Using 16S rRNA gene sequence (1515 bp) and BCL card (bioMérieux VITEK®), strain was identified as Bacillus sp. Crude biosurfactant reduced the surface tension of distilled water to 31.32 ±â€¯0.93 mN/m with CMC value of 0.3 mg/ml. Cell free supernatant showed excellent emulsification and oil displacement activity with stability up to 160 °C, pH 6-12 and 50 g/L NaCl conc. Biosurfactants were characterized using FTIR, TLC, HPLC LC-MS and NMR spectroscopy. Cell free supernatant reduced the contact angle of distilled water droplet from 117° to 52.28° and of 2% pesticide from 78.77° to 73.42° while 750 µg/ml of crude biosurfactant reduced from 66.06° to 56.33° for 2% pesticide and recovered 35% ULO and 12% HWCO from the contaminated sand. To our best of knowledge, this is the first report of thermo stable fatty alkene as a biosurfactant and is structurally different from previously reported, with having potential application in agriculture, oil recovery and bioremediation.


Assuntos
Alcenos/química , Alcenos/farmacologia , Bacillus/química , Pentanonas/química , Pentanonas/farmacologia , Tensoativos/química , Tensoativos/farmacologia , Alcenos/isolamento & purificação , Clorpirifos/química , Temperatura Alta , Concentração de Íons de Hidrogênio , Inseticidas/química , Óleos/química , Pentanonas/isolamento & purificação , Tensão Superficial , Tensoativos/isolamento & purificação , Molhabilidade
6.
J Chromatogr A ; 1489: 18-28, 2017 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-28190595

RESUMO

Recent technological advances in dynamic headspace sampling (D-HS) and the possibility to automate this sampling method have lead to a marked improvement in its the performance, a strong renewal of interest in it, and have extended its fields of application. The introduction of in-parallel and in-series automatic multi-sampling and of new trapping materials, plus the possibility to design an effective sampling process by correctly applying the breakthrough volume theory, have make profiling more representative, and have enhanced selectivity, and flexibility, also offering the possibility of fractionated enrichment in particular for high-volatility compounds. This study deals with fractionated D-HS ability to produce a sample representative of the volatile fraction of solid or liquid matrices. Experiments were carried out on a model equimolar (0.5mM) EtOH/water solution, comprising 16 compounds with different polarities and volatilities, structures ranging from C5 to C15 and vapor pressures from 4.15kPa (2,3-pentandione) to 0.004kPa (t-ß-caryophyllene), and on an Arabica roasted coffee powder. Three trapping materials were considered: Tenax TA™ (TX), Polydimethylsiloxane foam (PDMS), and a three-carbon cartridge Carbopack B/Carbopack C/Carbosieve S-III™ (CBS). The influence of several parameters on the design of successful fractionated D-HS sampling. Including the physical and chemical characteristics of analytes and matrix, trapping material, analyte breakthrough, purge gas volumes, and sampling temperature, were investigated. The results show that, by appropriately choosing sampling conditions, fractionated D-HS sampling, based on component volatility, can produce a fast and representative profile of the matrix volatile fraction, with total recoveries comparable to those obtained by full evaporation D-HS for liquid samples, and very high concentration factors for solid samples.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Verduras/química , Café/química , Pentanonas/análise , Pentanonas/isolamento & purificação , Sesquiterpenos Policíclicos , Sesquiterpenos/análise , Sesquiterpenos/isolamento & purificação , Temperatura , Pressão de Vapor , Volatilização
7.
J Biosci Bioeng ; 123(2): 209-215, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27773607

RESUMO

The grassy characteristic aroma perceived in brewed sake made from low-glutelin rice (Oryza sativa L. Mizuhonoka) was examined by gas chromatography-olfactometry and gas chromatography-mass spectrometry. By comparing the odor properties and Kovats retention indices to those of standard compounds, 4-mercapto-4-methylpentan-2-one (4MMP) was found to contribute to the characteristic aroma. Sake brewing using Mizuhonoka, low-glutelin rice, and Gin-ohmi (a control) revealed that 4MMP concentrations in Mizuhonoka sake samples were higher than those in Gin-ohmi samples over the fermentation period. The concentration in final Mizuhonoka sake was twice that of Gin-ohmi. To investigate the mechanism of 4MMP formation, the putative precursors, 4-S-cycteinyl-4-methylpentan-2-one (cys-4MMP) and 4-S-glutathionyl-4-methylpentan-2-one (glut-4MMP), in sake and its materials (rice and koji) were analyzed by ultra-performance liquid chromatography tandem mass-spectrometry. Cys-4MMP was not detected in all samples, while glut-4MMP was present in sake and its materials. The glut-4MMP concentration in sake was lower than that in Gin-ohmi over nearly the entire fermentation period, suggesting that conversion of the precursors to 4MMP was more effective in the mash of low-glutelin rice Mizuhonoka than in Gin-ohmi. The release of 4MMP during alcoholic fermentation from a model medium containing its precursors was examined. While no 4MMP release was observed in the control (no addition), with the addition of its precursors, the release of 4MMP increased as fermentation progressed. It was suggested that 4MMP was generated from both cys- and glut-4MMP by sake yeast. The perception threshold of 4MMP in sake was determined as 1.2 ng/L.


Assuntos
Bebidas Alcoólicas/análise , Aromatizantes , Odorantes , Oryza/química , Pentanonas/isolamento & purificação , Pentanonas/metabolismo , Compostos de Sulfidrila/isolamento & purificação , Compostos de Sulfidrila/metabolismo , Etanol/análise , Etanol/metabolismo , Fermentação , Aromatizantes/análise , Aromatizantes/metabolismo , Cromatografia Gasosa-Espectrometria de Massas/métodos , Glutationa/análogos & derivados , Glutationa/metabolismo , Glutens/metabolismo , Odorantes/análise , Oryza/metabolismo , Pentanonas/análise , Saccharomyces cerevisiae/metabolismo , Compostos de Sulfidrila/análise
8.
Biosens Bioelectron ; 53: 129-34, 2014 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-24135544

RESUMO

The aim of this study was to assess the classification accuracy of an e-Nose in detecting acute liver failure (ALF) in rats. Exhaled breath from 14 rats was repeatedly sampled by e-Nose (8 sensors) and an additional external CO2 sensor at three stages: healthy period; portacaval shunt; and during the development of ALF due to surgically induced complete liver ischemia. We performed principal component analysis (PCA) on the (grouped) sensor data in each stage and the classification accuracy of the first two principal components was assessed by the leave-one-out approach. In addition we performed gas chromatography-mass spectrometry (GC-MS) analysis of the exhaled breath from three rats. The first and second principal components from the PCA analysis of e-Nose data accounted for more than 95% variance in the data. Measurements in the ALF stage were contrasted with the measurements in the control stage. Leave-one-out validation showed classification accuracy of 96%. This accuracy was reached after 3h of ALF development, and was reached already after 2h when data of an external CO2 sensor were also included. GC-MS identified 2-butanol, 2-butanone, 2-pentanone and 1-propanol to be possibly elevated in the ALF stage. This is the first study to demonstrate that ALF in rats can be detected by e-Nose data analysis of the exhaled breath. Confirmation of these results in humans will be an important step forward in the non-invasive diagnosis of ALF.


Assuntos
Técnicas Biossensoriais/métodos , Dióxido de Carbono/isolamento & purificação , Nariz Eletrônico , Falência Hepática Aguda/diagnóstico , Animais , Testes Respiratórios/métodos , Butanóis/isolamento & purificação , Butanonas/isolamento & purificação , Expiração/fisiologia , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Falência Hepática Aguda/fisiopatologia , Pentanonas/isolamento & purificação , Ratos
9.
Talanta ; 116: 866-9, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24148486

RESUMO

We analyzed 21 neat acetone samples from 15 different suppliers to demonstrate the utility of a coupled stable isotope and trace contaminant strategy for distinguishing forensically-relevant samples. By combining these two pieces of orthogonal data we could discriminate all of the acetones that were produced by the 15 different suppliers. Using stable isotope ratios alone, we were able to distinguish 8 acetone samples, while the remaining 13 fell into four clusters with highly similar signatures. Adding trace chemical contaminant information enhanced discrimination to 13 individual acetones with three residual clusters. The acetones within each cluster shared a common manufacturer and might, therefore, not be expected to be resolved. The data presented here demonstrates the power of combining orthogonal data sets to enhance sample fingerprinting and highlights the role disparate data could play in future forensic investigations.


Assuntos
Acetona/isolamento & purificação , Ciências Forenses/métodos , Espectrometria de Massas/estatística & dados numéricos , Acetona/classificação , Isótopos de Carbono , Terrorismo Químico/prevenção & controle , Deutério , Análise Discriminante , Ciências Forenses/instrumentação , Hexanonas/isolamento & purificação , Humanos , Cetonas/isolamento & purificação , Pentanóis/isolamento & purificação , Pentanonas/isolamento & purificação
10.
Phytochemistry ; 95: 291-7, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23870821

RESUMO

An endophytic Cryptosporiopsis sp. was isolated from Clidemia hirta and analyzed for its secondary metabolites that lead to the isolation of three bioactive molecules. The compounds were purified from the culture broth of the fungus and their structures were determined by spectroscopic methods as (R)-5-hydroxy-2-methylchroman-4-one (1), 1-(2,6-dihydroxyphenyl)pentan-1-one (2) and (Z)-1-(2-(2-butyryl-3-hydroxyphenoxy)-6-hydroxyphenyl)-3-hydroxybut-2-en-1-one (3). Compound 1 exhibited significant cytotoxic activity against the human leukemia cell line, HL-60 with an IC50 of 4 µg/ml. This compound induced G2 arrest of the HL-60 cell cycle significantly. In addition, out of these compounds, 2 and 3 were active against several bacterial pathogens. Compound 2 was active against Bacillus cereus, Escherichia coli and Staphylococcus aureus with IC50 values varying from 18 to 30 µg/ml, and compound 3 displayed activity against Pseudomonas fluorescens with an IC50 value of 6 µg/ml. Compounds 2 and 3 are novel whereas compound 1 was reported earlier but the stereochemistry of its C-2 methyl is established for the first time.


Assuntos
Ascomicetos/química , Bactérias/efeitos dos fármacos , Butirofenonas/farmacologia , Cromonas/uso terapêutico , Leucemia/tratamento farmacológico , Melastomataceae/microbiologia , Pentanonas/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Bacillus/efeitos dos fármacos , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Butirofenonas/química , Butirofenonas/isolamento & purificação , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Cromonas/química , Cromonas/isolamento & purificação , Cromonas/farmacologia , Endófitos/química , Escherichia coli/efeitos dos fármacos , Células HL-60 , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Pentanonas/química , Pentanonas/isolamento & purificação , Pseudomonas fluorescens/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
11.
Phys Chem Chem Phys ; 14(10): 3450-9, 2012 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-22307583

RESUMO

The photochemistry of the chelated enol form of acetylacetone (AcAc) was investigated by UV excitation of the S(2) state at 266 nm in parahydrogen matrices, complemented by experiments in neon and normal hydrogen matrices. Infrared (IR) spectroscopy, combined with theoretical calculations, was used to identify the photoproducts. Isomerization towards various non-chelated forms (no intramolecular H-bond) of AcAc is the dominant channel whereas fragmentation is very minor. The isomerization kinetics is monitored by IR spectroscopy. Among the seven non-chelated conformers of AcAc, only three are formed in parahydrogen matrices, whereas four are observed in normal hydrogen matrices. This difference suggests that an active tunnelling process between conformers occurs in parahydrogen but is quenched in normal hydrogen where guest-host interactions are stronger. Fragmentation and isomerization of excited AcAc are discussed in the light of these new data. The role of the intermediate triplet state in the S(2)→ S(0) relaxation is confirmed, as the importance of phonons in the condensed phase.


Assuntos
Hidrogênio/química , Pentanonas/isolamento & purificação , Cinética , Pentanonas/química , Fotoquímica , Teoria Quântica , Espectroscopia de Infravermelho com Transformada de Fourier , Raios Ultravioleta
12.
Nat Prod Res ; 25(17): 1635-40, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22011223

RESUMO

The composition and in vitro antioxidant activities of the essential oil and methanol extract of the aerial parts of Viola tianshanica were evaluated in this research. GC-MS analysis of the essential oil resulted in the identification of 15 constituents, representing 89.67% of the oil. The major compounds detected in the essential oil were dibutyl phthalate (15.19%), hexadecanoate methyl (8.65%), n-hexadecanoic acid (3.07%) and 2,3-pentanedione (2.62%). Essential oil and methanol extract were tested for their antioxidant activities using 1,1-diphenyl-2-picryl-hydrazyl free radical scavenging and ß-carotene linoleic acid assay. In addition, the total phenol of essential oil, polar subfraction and non-polar subfraction were determined.


Assuntos
Antioxidantes/isolamento & purificação , Sequestradores de Radicais Livres/isolamento & purificação , Óleos Voláteis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Viola/química , Antioxidantes/análise , Antioxidantes/farmacologia , Compostos de Bifenilo , China , Dibutilftalato/isolamento & purificação , Sequestradores de Radicais Livres/análise , Sequestradores de Radicais Livres/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Técnicas In Vitro , Metanol , Óleos Voláteis/análise , Óleos Voláteis/farmacologia , Palmitatos/isolamento & purificação , Pentanonas/isolamento & purificação , Fenóis/análise , Picratos , Extratos Vegetais/análise , Extratos Vegetais/farmacologia , beta Caroteno
13.
Yakugaku Zasshi ; 128(12): 1797-802, 2008 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-19043299

RESUMO

A new perfumed dihydro-gamma-pyrone, 2-phenyl-5,6-dihydro-4H-pyrane-4-one (12) and seven components of C6-C5 phenylpentanone derivatives have been isolated from the neutral essential oil parts in cultured mycelium of Mycoleptodonoides aitchisonii. These compounds were elucidated on the basis of spectral data and syntheses. The derivatives are odorant components. The perfumed components in cultured mycelium were maximized amount at 7 days.


Assuntos
Agaricales/química , Micélio/química , Óleos Voláteis/química , Pentanonas/síntese química , Pentanonas/química , Pentanonas/isolamento & purificação
14.
Pest Manag Sci ; 63(9): 928-34, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17575567

RESUMO

Starting from the chemical structure of the botanical aphicides 1,5-diphenyl-1-pentanone and 1,5-diphenyl-2-penten-1-one, extracted from Stellera chamaejasme L., the authors designed and synthesized a series of novel compounds following the concept of bioisosterism. Their structures were established on the basis of (1)H NMR and GC-MS spectra, and the insecticidal activities of the compounds were evaluated against Aphis gossypii Glover. The results demonstrated that the substitution of a heterocycle for the phenyl ring was favourable. Thus, further modification of compound 2n, containing a furan ring, which showed excellent activity (LC(50) = 0.85 g L(-1)), is of some promise.


Assuntos
Afídeos , Inseticidas/síntese química , Chumbo/química , Pentanonas/química , Thymelaeaceae/química , Animais , Cromatografia Gasosa-Espectrometria de Massas , Ressonância Magnética Nuclear Biomolecular , Pentanonas/isolamento & purificação , Relação Estrutura-Atividade
15.
J Chromatogr A ; 1135(2): 151-7, 2006 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-17070822

RESUMO

Supercritical fluid extraction (SFE) of daphnoretin, 7-methoxy-daphnoretin and 1,5-diphenyl-1- pentanone from Stellera chamaejasme L. was performed. An orthogonal L9 (3)4 test design was applied to select the optimum extraction parameters including pressure, temperature, modifier and sample particle size on yield using an analytical-scale SFE system. The process was then scaled up by 100 times using a preparative SFE system under the optimized conditions of 25 MPa of pressure, 45 degrees C of temperature, 40-60 mesh of sample particle size and modified CO2 with 20% methanol. The yield of the crude extract from preparative SFE was 2.65%, which contained daphnoretin 25.2%, 7-methoxy-daphnoretin 22.8% and 1,5-diphenyl-1-pentanone 21.1%, respectively. Then the crude extract was successfully isolated and separated by preparative high-speed counter-current chromatography (HSCCC) with a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (10:13:13:10, v/v) by increasing the flow-rate of the mobile phase stepwise from 1.0 to 2.0 ml/min after 90 min. The target compounds isolated and purified by HSCCC were analyzed by high-performance liquid chromatography (HPLC). The separation produced total of 69.2mg of daphnoretin at 99.2% purity, 63.4 mg of 7-methoxy-daphnoretin at 98.7% purity and 58.3 mg of 1,5-diphenyl-1-pentanone at 98.1% purity from 300 mg of the crude extract in one-step separation. The recoveries of daphnoretin, 7-methoxy-daphnoretin and 1,5-diphenyl-1-pentanone were 90.8, 91.5 and 90.4%, respectively, in HSCCC isolation step and the chemical structure identification was carried out by MS, 1H NMR and 13C NMR.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Cumarínicos/isolamento & purificação , Distribuição Contracorrente/métodos , Pentanonas/isolamento & purificação , Thymelaeaceae/química , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Tamanho da Partícula , Espectrometria de Massas por Ionização por Electrospray
16.
Nat Prod Res ; 17(1): 71-4, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12674146

RESUMO

Phytochemical investigation of the leaves of Bidens pilosa lead to the isolation and characterization of a new disubstituted acetylacetone (1) named as 3-Propyl-3-(2,4,5-trimethoxy)benzyloxy-pentan-2,4-dione.


Assuntos
Bidens/química , Pentanonas/isolamento & purificação , Cromatografia em Camada Fina , Índia , Ressonância Magnética Nuclear Biomolecular , Pentanonas/química , Folhas de Planta/química
17.
Pest Manag Sci ; 57(3): 307-10, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11455662

RESUMO

1,5-Diphenyl-1-pentanone (A) and 1,5-diphenyl-2-penten-1-one (B) are natural products extracted for the first time from Stellera chamaejasme. Laboratory bioassay showed that the two products have strong contact activity and very good anti-feedant activity against Aphis gossypii and Schizaphis graminum. Both products showed dose-dependent relationships for both forms of activity against the two aphids, the contact activity of B being about twice that of A. Both products were inferior to methomyl in contact activity but superior in anti-feedant activity against the two aphids. This is the first report of aphicidal activity in these two compounds, which may represent a new class of aphicide.


Assuntos
Afídeos/efeitos dos fármacos , Inseticidas/toxicidade , Pentanonas/toxicidade , Extratos Vegetais/toxicidade , Animais , Bioensaio , Comportamento Alimentar/efeitos dos fármacos , Controle de Insetos/métodos , Inseticidas/química , Inseticidas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Magnoliopsida/química , Estrutura Molecular , Pentanonas/química , Pentanonas/isolamento & purificação , Extratos Vegetais/isolamento & purificação
18.
J Antibiot (Tokyo) ; 48(5): 380-6, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7797439

RESUMO

Determination of the mechanism of action of FK506 and cyclosporin A has yielded new molecular targets involved in signal transduction during T cell activation. A common target of FK506 and cyclosporin A is inhibition of activation of the NFAT transcription factor, for which a specific binding region is present in the promoter of the IL-2 gene. A reporter gene assay has been used to screen for agents that interfere with this early step in T cell activation. Simple aromatic compounds that block NFAT-dependent transcription and show in vitro immunosuppressive activity were isolated from the broth and mycelia of two Streptomyces sp. fermentations. The compounds were active at concentrations that were not directly cytotoxic.


Assuntos
Hidroquinonas/isolamento & purificação , Pentanóis/isolamento & purificação , Pentanonas/isolamento & purificação , Fatores de Transcrição/isolamento & purificação , Transcrição Gênica/efeitos dos fármacos , Animais , Bovinos , Fermentação , Regulação Enzimológica da Expressão Gênica , Hidroquinonas/química , Hidroquinonas/farmacologia , Terapia de Imunossupressão , Óperon Lac/efeitos dos fármacos , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Pentanóis/química , Pentanóis/farmacologia , Pentanonas/química , Pentanonas/farmacologia , Streptomyces , Linfócitos T/efeitos dos fármacos , Fatores de Transcrição/química , Fatores de Transcrição/farmacologia , beta-Galactosidase/genética
19.
Dev Biol ; 145(1): 195-200, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-1850369

RESUMO

The differentiation inducing factor (DIF) is essential for stalk cell formation in monolayers of Dictyostelium discoideum and is necessary for the expression of several prestalk cell-specific genes. DIF activity has been fractionated into a major species, designated DIF-1, and several minor species, including DIF-2. Although DIF-1 is an excellent inducer of stalk cell formation from vegetative cells, it is a poor inducer of stalk cell formation from prestalk cells. In contrast, DIF-2 is more active for the conversion of prestalk cells into stalk cells, than for the conversion of vegetative cells to stalk cells. The same results were obtained regardless of whether chemically synthesized or naturally occurring components were utilized. In addition, stalk cell formation was three- to fourfold higher when vegetative cells were incubated with DIF-1 for a suboptimal period and then subsequently incubated with DIF-2, than when cells were incubated with DIF-2 first and then subsequently with DIF-1. These results indicate a distinct role for DIF-2 during stalk cell formation and suggest the possibility that DIF-1 and DIF-2 act sequentially.


Assuntos
Dictyostelium/crescimento & desenvolvimento , Pentanonas/farmacologia , Diferenciação Celular , Cromatografia Líquida de Alta Pressão , AMP Cíclico/farmacologia , Dictyostelium/efeitos dos fármacos , Hexanonas/farmacologia , Pentanonas/isolamento & purificação
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