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1.
Int J Mol Sci ; 21(11)2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-32486319

RESUMO

Pterocarpans are derivatives of isoflavonoids, found in many species of the family Fabaceae. Sophora flavescens Aiton is a promising traditional Asian medicinal plant. Plant cell suspension cultures represent an excellent source for the production of valuable secondary metabolites. Herein, we found that methyl jasmonate (MJ) elicited the activation of pterocarpan biosynthetic genes in cell suspension cultures of S. flavescens and enhanced the accumulation of pterocarpans, producing mainly trifolirhizin, trifolirhizin malonate, and maackiain. MJ application stimulated the expression of structural genes (PAL, C4H, 4CL, CHS, CHR, CHI, IFS, I3'H, and IFR) of the pterocarpan biosynthetic pathway. In addition, the co-treatment of MJ and methyl-ß-cyclodextrin (MeßCD) as a solubilizer exhibited a synergistic effect on the activation of the pterocarpan biosynthetic genes. The maximum level of total pterocarpan production (37.2 mg/g dry weight (DW)) was obtained on day 17 after the application of 50 µM MJ on cells. We also found that the combined treatment of cells for seven days with MJ and MeßCD synergistically induced the pterocarpan production (trifolirhizin, trifolirhizin malonate, and maackiain) in the cells (58 mg/g DW) and culture medium (222.7 mg/L). Noteworthy, the co-treatment only stimulated the elevated extracellular production of maackiain in the culture medium, indicating its extracellular secretion; however, its glycosides (trifolirhizin and trifolirhizin malonate) were not detected in any significant amounts in the culture medium. This work provides new strategies for the pterocarpan production in plant cell suspension cultures, and shows MeßCD to be an effective solubilizer for the extracellular production of maackiain in the cell cultures of S. flavescens.


Assuntos
Acetatos/farmacologia , Ciclodextrinas/farmacologia , Ciclopentanos/farmacologia , Oxilipinas/farmacologia , Raízes de Plantas/metabolismo , Pterocarpanos/metabolismo , Sophora/efeitos dos fármacos , Sophora/metabolismo , Biotecnologia , Meios de Cultura , Sinergismo Farmacológico , Flavonoides/análise , Glucosídeos/análise , Compostos Heterocíclicos de 4 ou mais Anéis/análise , Espectroscopia de Ressonância Magnética , Malonatos/análise , Extratos Vegetais/química , Folhas de Planta/metabolismo , Plantas Medicinais , Pterocarpanos/análise
2.
Electrophoresis ; 40(18-19): 2256-2262, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30793781

RESUMO

1-propanol is a primary alcohol extensively used in the pharmaceutical, chemical, and food industries. It has been also found as a contaminant in the atmosphere and is considered a model compound to mimic the behavior and fate of aliphatic alcohols exposed to environmental conditions. In order to understand that role of relevant variables, this paper presents results obtained with a simple experimental set-up to investigate the reactivity of 1-propanol under mild oxidizing conditions. Coupling this system with CE-C4 D allowed the quantification of the carboxylic acids formed. For the described experiments, aqueous solutions of 1-propanol were placed inside a photoreactor and oxidized upon the addition of TiO2 and/or H2 O2 . According to the described results, the addition of H2 O2 (0.1% w/w) was the most significant variable, roughly tripled the amount of carboxylic acids generated and led to the conversion of up to 70% of the initially available 1-propanol (1 mmol/L). More importantly, the reaction yielded the formation (within 10 min) of propionate (50 µmol/L), acetate (400 µmol/L), formate (50 µmol/L), and malonate (200 µmol/L). The latter is critically important because it represents the first example of the photochemical oxidation of both terminal carbons of the C3 -chain of 1-propanol under mild conditions, and opens new avenues for the production of this important chemical building block.


Assuntos
1-Propanol , Peróxido de Hidrogênio , Fotólise , 1-Propanol/análise , 1-Propanol/química , 1-Propanol/efeitos da radiação , Condutividade Elétrica , Eletroforese Capilar , Malonatos/análise , Malonatos/química , Oxirredução , Fotólise/efeitos dos fármacos , Fotólise/efeitos da radiação , Raios Ultravioleta
3.
Angiol Sosud Khir ; 24(4): 72-74, 2018.
Artigo em Russo | MEDLINE | ID: mdl-30531772

RESUMO

The authors analysed the effect of Venarus on the endothelial function in patients suffering from lower limb varicose veins. Our open-label prospective study included a total of 100 patients diagnosed as having CEAP class C1-C2 varicose veins and divided into two equal groups. Dynamic assessment of the clinical course of the disease in Group One patients was carried out on the background of taking Venarus and compression therapy, with Group Two patients evaluated without taking Venarus. At defined stages we determined the level of biochemical markers of endothelial function. The obtained findings demonstrated that the use of phlebotonic Venarus resulted in decreased activity of lipid peroxidation processes and reduced activity of antioxidant system enzymes. Using Venarus was followed by a statistically significant decrease in the concentration of malonic dialdehyde (from 1.220±0.190 µmol/l at baseline to 0.858±0.231 µmol/l after 2 months of treatment), whereas in Group Two patients the changes were insignificant (1.191±0.204 µmol/l before treatment and 1.138±0.175 µmol/l at 2 months thereafter). Patients taking Venarus were also found to have a higher level of nitric oxide metabolites compared with the patients treated by compression therapy alone (51.646±11.757 and 36.310±6.921 µmol/l in Groups One and Two, respectively). Hence, an evidence-based conclusion was drawn that Venarus proved efficient and may therefore be prescribed as pharmacotherapy for correction of endothelial dysfunction.


Assuntos
Bandagens Compressivas , Diosmina/administração & dosagem , Endotélio Vascular/efeitos dos fármacos , Varizes , Insuficiência Venosa , Adulto , Antioxidantes/administração & dosagem , Monitoramento de Medicamentos , Endotélio Vascular/metabolismo , Feminino , Flavonoides/administração & dosagem , Humanos , Masculino , Malonatos/análise , Pessoa de Meia-Idade , Óxido Nítrico/metabolismo , Resultado do Tratamento , Varizes/diagnóstico por imagem , Varizes/tratamento farmacológico , Varizes/fisiopatologia , Insuficiência Venosa/diagnóstico , Insuficiência Venosa/tratamento farmacológico , Insuficiência Venosa/etiologia
4.
Mol Genet Metab ; 124(1): 57-63, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29526615

RESUMO

Ethylmalonic encephalopathy (EE) is a devastating neurodegenerative disease caused by mutations in the ETHE1 gene critical for hydrogen sulfide (H2S) detoxification. Patients present in infancy with hypotonia, developmental delay, diarrhea, orthostatic acrocyanosis and petechiae. Biochemical findings include elevated C4, C5 acylcarnitines and lactic and ethylmalonic acid (EMA) in body fluids. Current treatment modalities include metronidazole and N-acetylcysteine (NAC) to lower the production and promote detoxification of toxic H2S. Patients are typically identified after the onset of clinical symptoms and there is limited information about long term response to treatment. We report the findings of two unrelated patients with EE, identified through newborn screening, who were managed with conventional treatment (NAC, metronidazole alternated with neomycin) and in patient 2, a novel dietary treatment restricting sulfur containing amino acids. Pathogenic mutations were confirmed in the ETHE1 gene (homozygous splice site mutation in patient 1, c.505 + 1G > A; compound heterozygous mutations in patient 2, c.131_132delAG + c.566delG). Both patients were started on metronidazole and NAC by 10 weeks of age and treated for 23 months. Patient 1 did not accept the metabolic formula due to palatability and parental refusal for gastrostomy tube placement. She demonstrated improved biomarkers (EMA, lactic acid and thiosulfate) and an attenuated clinical course. Patient 2 was started on a low methionine and cysteine diet at 8 months of age utilizing SOD Anamix® Early Years, (Nutricia). Baseline EMA levels were (642 mg/g Cr; n = 2) and decreased with medical treatment by 38% to a mean of 399 (n = 4, SD = 71, p 0.0013). With dietary treatment EMA levels were further reduced by 42% to a mean of 233 (n = 8, SD = 52, p 0.0030). Lactic acid, thiosulfates and clinical outcomes were also improved. Our long-term follow-up confirms previous reports of clinical improvement with NAC and metronidazole treatment. Additionally, our studies suggest that a diet restricted in sulfur-containing amino acids results in further improvement in clinical outcomes and biochemical markers.


Assuntos
Aminoácidos/administração & dosagem , Encefalopatias Metabólicas Congênitas/dietoterapia , Encefalopatias Metabólicas Congênitas/tratamento farmacológico , Triagem Neonatal , Púrpura/dietoterapia , Púrpura/tratamento farmacológico , Acetilcisteína/uso terapêutico , Aminoácidos/química , Biomarcadores , Encefalopatias Metabólicas Congênitas/diagnóstico , Cisteína , Dieta/métodos , Feminino , Humanos , Lactente , Recém-Nascido , Ácido Láctico/análise , Masculino , Malonatos/análise , Metionina , Metronidazol/uso terapêutico , Proteínas Mitocondriais/genética , Mutação , Proteínas de Transporte Nucleocitoplasmático/genética , Púrpura/diagnóstico , Enxofre
5.
J Proteome Res ; 16(5): 2030-2043, 2017 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-28365990

RESUMO

As a recently validated reversible post translational modification, lysine malonylation regulates diverse cellular processes from bacteria to mammals, but its existence and function in photosynthetic organisms remain unknown. Cyanobacteria are the most ancient group of photosynthetic prokaryotes and contribute about 50% of the total primary production on Earth. Previously, we reported the lysine acetylome in the model cyanobacterium Synechocystis sp. PCC 6803 (Synechocystis). Here we performed the first proteomic survey of lysine malonylation in Synechocystis using highly accurate tandem mass spectrometry in combination with affinity purification. We identified 598 lysine malonylation sites on 339 proteins with high confidence in total. A bioinformatic analysis suggested that these malonylated proteins may play various functions and were distributed in diverse subcellular compartments. Among them, many malonylated proteins were involved in cellular metabolism. The functional significance of lysine malonylation in the metabolic enzyme activity of phosphoglycerate kinase (PGK) was determined by site-specific mutagenesis and biochemical studies. Interestingly, 27 proteins involved in photosynthesis were found to be malonylated for the first time, suggesting that lysine malonylation may be involved in photosynthesis. Thus our results provide the first lysine malonylome in a photosynthetic organism and suggest a previously unexplored role of lysine malonylation in the regulation of metabolic processes and photosynthesis in Synechocystis as well as in other photosynthetic organisms.


Assuntos
Lisina/metabolismo , Malonatos/análise , Fotossíntese , Proteínas de Bactérias/análise , Cianobactérias/metabolismo , Fosfoglicerato Quinase/metabolismo , Proteômica/métodos , Synechocystis/metabolismo , Espectrometria de Massas em Tandem
6.
J Phys Chem A ; 118(13): 2488-97, 2014 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-24628358

RESUMO

We utilize a new experimental technique, humidity-controlled thermogravimetric analysis (HTGA), to determine temperature-dependent deliquescence relative humidities (DRH) and to determine the equilibrium concentration of a solution at a given temperature and relative humidity. To that end, we have investigated the malonic acid/water system determining the DRH and concentration/RH relationship in the temperature range 303-278 K. Excellent agreement is found with literature values for the DRH of malonic acid as a function of temperature and for the concentration/RH relationship at several temperatures. Thus, we extend the DRH and concentration/RH relationship to a broader temperature range and are using the HTGA experiments to investigate other organic acids.


Assuntos
Malonatos/análise , Temperatura , Termogravimetria/métodos , Umidade , Termogravimetria/instrumentação , Água/química
7.
J Hazard Mater ; 263 Pt 2: 479-85, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-24225584

RESUMO

Chemical warfare agent simulants are often used as an agent surrogate to perform environmental testing, mitigating exposure hazards. This work specifically addresses the assessment of downwind agent vapor concentration resulting from an evaporating simulant droplet. A previously developed methodology was used to estimate the mass diffusivities of the chemical warfare agent simulants methyl salicylate, 2-chloroethyl ethyl sulfide, di-ethyl malonate, and chloroethyl phenyl sulfide. Along with the diffusivity of the chemical warfare agent bis(2-chloroethyl) sulfide, the simulant diffusivities were used in an advection-diffusion model to predict the vapor concentrations downwind from an evaporating droplet of each chemical at various wind velocities and temperatures. The results demonstrate that the simulant-to-agent concentration ratio and the corresponding vapor pressure ratio are equivalent under certain conditions. Specifically, the relationship is valid within ranges of measurement locations relative to the evaporating droplet and observation times. The valid ranges depend on the relative transport properties of the agent and simulant, and whether vapor transport is diffusion or advection dominant.


Assuntos
Poluentes Atmosféricos/análise , Substâncias para a Guerra Química/análise , Descontaminação/métodos , Difusão , Monitoramento Ambiental/métodos , Recuperação e Remediação Ambiental , Gases , Malonatos/análise , Modelos Teóricos , Peso Molecular , Gás de Mostarda/análogos & derivados , Gás de Mostarda/análise , Tamanho da Partícula , Reprodutibilidade dos Testes , Salicilatos/análise , Sulfetos/análise , Temperatura
8.
J Pharm Biomed Anal ; 64-65: 56-63, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22387101

RESUMO

To clarify the effects of malonyl ginsenosides (MGR) on evaluation and quality control of Panax ginseng, the contents of neutral and malonyl ginsenosides from P. ginseng were examined by high-performance liquid chromatography equipped with UV-VIS detector (HPLC-UV) during extraction, processing and storage. Several solvents, including water, ethanol, methanol, and n-butanol were used in the cold-soaked extraction (CSE). Among the four extraction solvents, methanol was found to be the most efficient. CSE was compared with other extraction methods such as Soxhlet extraction (SE), heat reflux extraction (HRE), ultrasonic-assisted extraction (UAE), and microwave-assisted extraction (MAE). The content of MGR showed significant differences, higher in CSE and UAE; lower in MAE and HRE; no MGR could be detected after SE. However, the total contents of neutral and malonyl ginsenosides were not different. Meanwhile, white ginseng, stored at 25°C in air of low humidity, showed a marked decrease in the concentration of MGR from 1.19% to 0.63% but with an increase in the neutral ginsenosides from 1.12% to 1.53% after 0-9-month storage. The results indicated that MGR changed dynamically in P. ginseng with different extraction solvents, extraction methods and increasing storage time. The total ginsenosides was not only underestimated but also determined imprecisely by ignoring malonyl ginsenosides. On the basis of our results, we suggest that malonyl ginsenosides should be transformed into the corresponding neutral ginsenosides during sample preparation for quality control and evaluation of P. ginseng. Then the content of six neutral ginsenosides in samples was used as the true level of total ginsenosides. The results reported here might provide useful information for accurate evaluation and quality control of P. ginseng.


Assuntos
Ginsenosídeos/química , Extração Líquido-Líquido/métodos , Malonatos/química , Panax/química , Extratos Vegetais/química , Cromatografia Líquida de Alta Pressão/métodos , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Ginsenosídeos/análise , Malonatos/análise , Micro-Ondas , Estrutura Molecular , Extratos Vegetais/isolamento & purificação , Controle de Qualidade , Solventes/química , Fatores de Tempo , Ultrassom/métodos
9.
Biomed Chromatogr ; 26(10): 1143-9, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22222555

RESUMO

Accurate, selective, sensitive and precise HPTLC-densitometric and RP-HPLC methods were developed and validated for determination of bumadizone calcium semi-hydrate in the presence of its alkaline-induced degradation product and in pharmaceutical formulation. Method A uses HPTLC-densitometry, depending on separation and quantitation of bumadizone and its alkaline-induced degradation product on TLC silica gel 60 F(254) plates, using hexane-ethyl acetate-glacial acetic acid (8:2:0.2, v/v/v) as a mobile phase followed by densitometric measurement of the bands at 240 nm. Method B comprises RP-HPLC separation of bumadizone and its alkaline-induced degradation product using a mobile phase consisting of methanol-water-acetonitrile (20:30:50, v/v/v) on a Phenomenex C(18) column at a flow-rate of 2 mL/min and UV detection at 235 nm. The proposed methods were successfully applied to the analysis of bumadizone either in bulk powder or in pharmaceutical formulation without interference from other dosage form additives, and the results were statistically compared with the established method.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa/métodos , Malonatos/análise , Acetonitrilas , Densitometria/métodos , Concentração de Íons de Hidrogênio , Malonatos/química , Metanol , Pós/química , Análise de Regressão , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Comprimidos/química
10.
J AOAC Int ; 95(6): 1644-51, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23451380

RESUMO

Rapid, simple, and selective methods for determining amantadine HCI and acyclovir antiviral drugs in pharmaceutical and plasma samples were developed using 1H-NMR spectroscopy with dimethyl sulfoxide (DMSO-d6) as the solvent. Integrations of the 1H-NMR signals at 2.07 and 7.82 ppm were used, respectively, for quantifying the two drugs, with the malonic acid signal at 3.24 ppm as the internal reference signal. Average recoveries of 98.24-101.00 +/- 4.82% and 97.7-100.38 +/- 3.36% were obtained for amantadine HCI and acyclovir in pharmaceutical samples, respectively. Average recoveries of 97.36-103.68 +/- 2.99 and 93.81-99.80 +/- 2.93 were obtained, respectively, for both drugs in plasma samples. The statistical Student's t-test gave t-values < or = 1.41 for analyzed pharmaceutical samples and t-values < or = 0.29 for analyzed plasma samples. These values indicated insignificant difference between the real and measured contents at the 95% confidence level. Application of the statistical F-test for the analytical results of amantadine HCI gave F-values < or = 6.44 and 2.80 in pharmaceutical and plasma samples, respectively. F-values < or = 6.82 and 3.86 were obtained for acyclovir in pharmaceutical and plasma, respectively. These values indicated insignificant differences in precisions between the developed NMR methods and arbitrarily chosen HPLC methods reported for determining both drugs in pharmaceutical and plasma samples.


Assuntos
Aciclovir/análise , Aciclovir/sangue , Amantadina/análise , Amantadina/sangue , Antivirais/análise , Antivirais/sangue , Calibragem , Cápsulas/análise , Dimetil Sulfóxido , Humanos , Limite de Detecção , Espectroscopia de Ressonância Magnética , Malonatos/análise , Malonatos/sangue , Preparações Farmacêuticas/análise , Pós/análise , Padrões de Referência , Reprodutibilidade dos Testes , Solventes
11.
Rapid Commun Mass Spectrom ; 25(10): 1437-44, 2011 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-21504010

RESUMO

Vapors of four chemical warfare agent (CWA) stimulants, 2-chloroethyl ethyl sulfide (CEES), diethyl malonate (DEM), dimethyl methylphosphonate (DMMP), and methyl salicylate (MeS), were detected, identified, and quantitated using a fully automated, field-deployable, miniature mass spectrometer. Samples were ionized using a glow discharge electron ionization (GDEI) source, and ions were mass analyzed with a cylindrical ion trap (CIT) mass analyzer. A dual-tube thermal desorption system was used to trap compounds on 50:50 Tenax TA/Carboxen 569 sorbent before their thermal release. The sample concentrations ranged from low parts per billion [ppb] to two parts per million [ppm]. Limits of detection (LODs) ranged from 0.26 to 5.0 ppb. Receiver operating characteristic (ROC) curves are presented for each analyte. A sample of CEES at low ppb concentration was combined separately with two interferents, bleach (saturated vapor) and diesel fuel exhaust (1%), as a way to explore the capability of detecting the simulant in an environmental matrix. Also investigated was a mixture of the four CWA simulants (at concentrations in air ranging from 270 to 380 ppb). Tandem mass (MS/MS) spectral data were used to identify and quantify the individual components.


Assuntos
Ar/análise , Substâncias para a Guerra Química/análise , Espectrometria de Massas em Tandem/instrumentação , Espectrometria de Massas em Tandem/métodos , Substâncias para a Guerra Química/isolamento & purificação , Malonatos/análise , Malonatos/isolamento & purificação , Miniaturização , Modelos Químicos , Gás de Mostarda/análogos & derivados , Gás de Mostarda/análise , Gás de Mostarda/isolamento & purificação , Compostos Organofosforados/análise , Compostos Organofosforados/isolamento & purificação , Curva ROC , Salicilatos/análise , Salicilatos/isolamento & purificação , Sensibilidade e Especificidade
12.
J Sep Sci ; 33(4-5): 570-81, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20162633

RESUMO

A structurally identified new compound named malonylastragaloside I was isolated and obtained from Radix Astragali. This novel compound was found to be unstable especially under high temperature and pH value. Using sonication extraction, addition of formic acid, and an efficient medium pressure ODS C(18) column chromatography method, a high yield of 40 mg of this compound was obtained from 150 g of powdered crude herbal medicine. Malonylastragaloside I was structurally characterized by NMR and ESI quadrupole TOF MS. With the strategy of target precursor ions scan, a total of 22 astragalosides including 8 astragaloside malonates were screened and characterized from the methanolic extract of Radix Astragali by HPLC-Q-TOF/MS. The eight astragaloside malonates were found in both Astragalus membranaceus var. mongholicus and A. membranaceus. The results provided a real profile of various triterpene saponins in Radix Astragali. It is a first report regarding isolation and characterization of astragaloside malonates in Astragalus species.


Assuntos
Astragalus propinquus/química , Malonatos/análise , Raízes de Plantas/química , Cromatografia Líquida de Alta Pressão , Formiatos/química , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Saponinas/química , Espectrometria de Massas por Ionização por Electrospray , Temperatura , Triterpenos/química
13.
J Magn Reson ; 200(1): 130-3, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19608443

RESUMO

The analysis of deuterium wideline NMR spectra has been an essential step in characterizing the dynamics of molecules in the solid-state. Although clearly important, the identification of quadrupolar coupling constants (QCCs) from the powder patterns is often complicated by poor sensitivity and/or spectral overlap. Previously, others have demonstrated the utility of "de-Pake-ing", a mathematical transform that yields the QCCs in a straightforward manner for symmetric (eta=0) sites. In this short paper, we describe our analysis of a powder sample of perdeutero-malonic acid, a molecule with two distinct deuteron environments and asymmetries. The methylene sites are immediately amenable to the standard de-Pake-ing transform analysis due to their low asymmetry. However, the de-Pake-ing methodology for the acid deuterons, for which the asymmetry deviates significantly from zero, requires more analysis to extract their QCCs. The impact of this work on the future application of de-Pake-ing to a wider range of samples is also discussed.


Assuntos
Malonatos/análise , Algoritmos , Simulação por Computador , Deutério , Análise de Fourier , Análise dos Mínimos Quadrados , Espectroscopia de Ressonância Magnética , Malonatos/química , Modelos Moleculares , Dinâmica não Linear , Pós
14.
Environ Sci Technol ; 42(24): 9268-75, 2008 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-19174903

RESUMO

This study systematically examined effects of analytical approaches on resultant concentrations of oxalic acid, oxalates, malonic acid, and malonates. Results demonstrated that employing separate water extraction and THF extraction is required to properly quantify dicarboxylic acids vs dicarboxylates using IC or GC-MS. Applications of the recommended methods to analyze PM2.5 collected in Singapore showed that concentrations of oxalate ranged from 361.4 to 481.4 ng m(-3), which were 10-14.7 times higher than that of oxalic acid. Unlike that of oxalates, malonate concentrations (10.5-23.4 ng m(-3)) were no more than half of malonic acid concentration (43.8-53.9 ng m(-3)) in PM2.5. Concentration ratios of oxalate-to-oxalic acid and malonate-to-malonic acid obtained from this work were applied to reported literature data; as a first approximation, in urban environments similar to that in Singapore, quantifiable oxalic acid, oxalates, malonic acid, and malonates in PM2.5 could range from 7.6 to 68.0, 82.2 to 732.8, 6.3 to 150, and 1.3 to 60 ng m(-3), respectively. Because photooxidation properties and hygroscopicity of dicarboxylic acids can substantially differ from that of dicarboxylates, more studies are needed to quantify ambient oxalic acid and malonic acid vs oxalates and malonates.


Assuntos
Atmosfera/química , Malonatos/análise , Oxalatos/análise , Material Particulado/química , Tamanho da Partícula , Padrões de Referência , Soluções
15.
J Agric Food Chem ; 55(4): 1321-6, 2007 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-17253711

RESUMO

A screening method using LC-DAD-ESI/MS was applied to the analysis of flavonoids in celery, Chinese celery, and celery seeds (Apium graveolens L. and varieties). Fifteen flavonoid glycosides were detected in the three celery materials. They were identified as luteolin 7-O-apiosylglucoside, luteolin 7-O-glucoside, apigenin 7-O-apiosylglucoside, chrysoeriol 7-O-apiosylglucoside, chrysoeriol 7-O-glucoside, and more than 10 malonyl derivatives of these glycosides. The identification of the malonyl derivatives was confirmed by their conversion into glycosides upon heating and by comparison of some of the malonates with malonates that had previously been identified in red bell pepper and parsley. The concentrations of the glycosides and the malonyl glycosides in the three materials were estimated by comparison to aglycone standards. This is the first report of the presence of these glycosylated flavonoid malonates in celery.


Assuntos
Apium/química , Flavonoides/análise , Glucosídeos/análise , Malonatos/análise , Sementes/química , Cromatografia Líquida de Alta Pressão , Flavonoides/química , Glicosilação , Malonatos/química , Espectrometria de Massas por Ionização por Electrospray
16.
Phytochemistry ; 68(5): 673-9, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17174991

RESUMO

The triacyl anthocyanins, Leschenaultia blue anthocyanins 1 and 2 (LBAs 1 and 2) were isolated from the blue flowers of Leschenaultia R. Br. cv. Violet Lena (Goodeniaceae), in which LBA 1 was present as a dominant pigment. The structure of LBA 1 was elucidated to be delphinidin 3-O-[6-O-(malonyl)-beta-D-glucopyranoside]-7-O-[6-O-(4-O-(6-O-(4-O-(beta-D-glucopyranosyl)-trans-caffeoyl)-beta-D-glucopyranosyl)-trans-caffeoyl)-beta-D-glucopyranoside] by application of chemical and spectroscopic methods. Since LAB 2 was isolated in small amount, its structure was tentatively assigned as either delphinidin 3-(malonylglucoside)-7-[(glucosyl-p-coumaroyl)-(glucosylcaffeoyl)-glucoside] or delphinidin 3-(malonyl-glucoside)-7-[(glucosyl-caffeoyl)(glucosyl-p-coumaroyl)-glucoside]. This is the first report of the occurrence of 7-polyacylated anthocyanins in the family of Goodeniaceae, although others have been found in the families of the Ranunculaceae, Campanulaceae, and Compositae. Moreover, delphinidin 3-glycoside-7-di-(glucosylcaffeoyl)-glucoside has been reported only in the flowers of Platycodon grandiflorum (Campanulaceae). From a chemotaxonomical viewpoint, the Goodeniaceae may be closely related to the Campanulaceae.


Assuntos
Antocianinas/análise , Asteraceae/química , Flores/química , Glucosídeos/química , Acilação , Antocianinas/química , Antocianinas/isolamento & purificação , Ácidos Cafeicos/análise , Glucosídeos/isolamento & purificação , Malonatos/análise , Modelos Moleculares , Conformação Molecular
17.
J Med Genet ; 43(4): 340-6, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16183799

RESUMO

Mutations in ETHE1, a gene located at chromosome 19q13, have recently been identified in patients affected by ethylmalonic encephalopathy (EE). EE is a devastating infantile metabolic disorder, characterised by widespread lesions in the brain, hyperlactic acidaemia, petechiae, orthostatic acrocyanosis, and high levels of ethylmalonic acid in body fluids. To investigate to what extent ETHE1 is responsible for EE, we analysed this gene in 29 patients with typical EE and in 11 patients presenting with early onset progressive encephalopathy with ethylmalonic aciduria (non-EE EMA). Frameshift, stop, splice site, and missense mutations of ETHE1 were detected in all the typical EE patients analysed. Western blot analysis of the ETHE1 protein indicated that some of the missense mutations are associated with the presence of the protein, suggesting that the corresponding wild type amino acid residues have a catalytic function. No ETHE1 mutations were identified in non-EE EMA patients. Experiments based on two dimensional blue native electrophoresis indicated that ETHE1 protein works as a supramolecular, presumably homodimeric, complex, and a three dimensional model of the protein suggests that it is likely to be a mitochondrial matrix thioesterase acting on a still unknown substrate. Finally, the 625G-->A single nucleotide polymorphism in the gene encoding the short chain acyl-coenzyme A dehydrogenase (SCAD) was previously proposed as a co-factor in the aetiology of EE and other EMA syndromes. SNP analysis in our patients ruled out a pathogenic role of SCAD variants in EE, but did show a highly significant prevalence of the 625A alleles in non-EE EMA patients.


Assuntos
Encefalopatias Metabólicas/genética , Proteínas Mitocondriais/genética , Mutação , Proteínas de Transporte Nucleocitoplasmático/genética , Alelos , Western Blotting , Encefalopatias Metabólicas/diagnóstico , Butiril-CoA Desidrogenase/genética , Butiril-CoA Desidrogenase/fisiologia , Análise Mutacional de DNA , Eletroforese em Gel Bidimensional , Humanos , Malonatos/análise , Proteínas Mitocondriais/química , Proteínas Mitocondriais/metabolismo , Modelos Moleculares , Proteínas de Transporte Nucleocitoplasmático/química , Proteínas de Transporte Nucleocitoplasmático/metabolismo , Filogenia , Polimorfismo de Nucleotídeo Único
18.
J Chem Ecol ; 31(6): 1285-98, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16222771

RESUMO

The effect of disturbed root nodulation on the quantitative and qualitative composition of the main isoflavonoid glucoside malonates, glucosides, and aglycones in the leaves of Trifolium pratense L. grown under waterlogging conditions was investigated. Isoflavonoids are involved in the regulation of root nodule activity and the establishment of the mycorrhizal association. Isoflavonoid determination was performed using reversed-phase liquid chromatography coupled to mass spectrometric and UV absorbance detection. In response to waterlogging, the concentrations of biochanin A and biochanin A-7-O-glucoside malonate, biochanin A-7-O-glucoside, and genistein-7-O-glucoside in the leaves increased two- to threefold after a lag period of 3 wk because of disturbed root nodulation. The other isoflavones detected formononetin, formononetin-7-O-glucoside malonate, and formononetin-7-O-glucoside-did not show any significant changes related to waterlogging. After restoring normal soil water conditions, the concentrations of biochanin A and its glucoside and glucoside-malonate rapidly returned to the initial values, whereas the concentration of genistein-7-O-glucoside remained high.


Assuntos
Isoflavonas/análise , Folhas de Planta/química , Raízes de Plantas/química , Trifolium/química , Água/efeitos adversos , Adaptação Fisiológica , Cromatografia Gasosa-Espectrometria de Massas , Genisteína/análise , Genisteína/metabolismo , Glicosídeos/análise , Glicosídeos/metabolismo , Isoflavonas/metabolismo , Malonatos/análise , Malonatos/metabolismo , Espectrofotometria Ultravioleta
19.
Magn Reson Chem ; 43(7): 563-6, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15864818

RESUMO

Because of its reactivity, malonic acid diamide (1) was initially identified as an alternative precursor for the development of a new class of high-density insensitive energetic materials possessing low sensitivity to thermal decomposition and detonation by impact. Nitration of 1 was studied under different conditions and led to three different tautomeric forms (2-4) of nitromalonic acid diamine. Using stronger oxidation conditions the oxadiazole 5 was generated in one step. We report the full 1H, 13C and 15N NMR structural characterization of these compounds in DMSO together with thermal, infrared, mass spectrometric and x-ray analysis. Experimental data obtained for 4 are compatible with an enol-imine form. Our interpretation is consistent with calculated 1H and 13C NMR spectra (ACD).


Assuntos
Diamida/química , Espectroscopia de Ressonância Magnética/métodos , Malonatos/química , Compostos de Nitrogênio/química , Isótopos de Carbono , Diamida/análise , Isomerismo , Malonatos/análise , Compostos de Nitrogênio/análise , Prótons
20.
J Org Chem ; 68(6): 2479-82, 2003 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-12636421

RESUMO

A variety of alpha,alpha-disubstituted malonamides undergo enantioselective hydrolysis with Rhodococcus sp. CGMCC 0497 to give challenging enantiopure alpha,alpha-disubstituted malonamic acids with up to >99% enantiomeric excesses and 98% chemical yields. The enantioselectivity originated from the effects of a highly enantioselective amidase. The products could be converted to valuable (R)- or (S)-alpha,alpha-dialkylated amino acids after routine conversions.


Assuntos
Amidoidrolases/metabolismo , Aminoácidos/síntese química , Malonatos/síntese química , Rhodococcus/metabolismo , Catálise , Hidrólise , Malonatos/análise , Malonatos/metabolismo , Estrutura Molecular , Rhodococcus/enzimologia , Estereoisomerismo , Relação Estrutura-Atividade
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