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1.
Anal Methods ; 13(42): 4994-5002, 2021 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-34633400

RESUMO

In this work, a covalent organic framework (COF) TAPT-TFP-COF containing a triazine ring was prepared by a typical Schiff base condensation reaction of 1,3,5-tris-(4-aminophenyl)triazine (TAPT) and 1,3,5-triformyl phloroglucinol (TFP). The TAPT-TFP-COF and carboxyl-functionalized multi-wall carbon nanotubes (COOH-MWCNTs) were drip-coated on glassy carbon electrode respectively to develop a novel and simple electrochemical sensor in order to simultaneously detect dopamine (DA) and paracetamol (PA). COOH-MWCNTs interconnected the TAPT-TFP-COF and acted as bridges between the COF particles, which had a good synergistic effect and accelerated electron transfer. Under optimal conditions, linear responses were obtained over the concentration range 1-190 µM for DA and PA with limits of detection (LOD) of 0.14 µM and 0.19 µM, respectively. Furthermore, the fabricated sensor possesses outstanding repeatability and high selectivity, and can be applied for the determination of DA and PA in dopamine injection and acetaminophen drugs with satisfactory recoveries.


Assuntos
Estruturas Metalorgânicas , Nanotubos de Carbono , Acetaminofen/análise , Dopamina/análise , Nanotubos de Carbono/química , Floroglucinol/análise , Floroglucinol/química , Tirosina/análogos & derivados
2.
J Chromatogr Sci ; 59(3): 212-216, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33257934

RESUMO

Five non-polar phloroglucinol derivatives, viz. pseudo-aspidin, α-kosin and agripinol A-C were isolated and purified from Agrimonia pilosa Ledeb by semi-preparative counter-current chromatography. The separation was performed by a two-step elution with non-aqueous solvent systems. In the first step, an elution mode of a two-phase solvent system consisting of n-hexane-acetonitrile-dichloromethane-methanol (6:6:0.5:0.5, v/v/v/v) was used. We obtained sample Ι containing three components (47.0 mg) and sample ΙΙ containing two components (24.8 mg) from crude extract (371.0 mg). In the second step, sample Ι was successfully separated by closed-loop recycling mode with a solvent system consisting of n-hexane-acetonitrile-dichloromethane (10:7:3, v/v/v), yielding 17.8 mg of pseudo-aspidin, 18.5 mg of α-kosin and 6.4 mg of agripinol A. The other two compounds-8.7 mg of agripinol B and 13.6 mg of agripinol C-were obtained from sample ΙΙ in the same manner. All the isolated compounds had a high purity exceeding 95%.


Assuntos
Agrimonia/química , Distribuição Contracorrente/métodos , Floroglucinol , Isomerismo , Floroglucinol/análogos & derivados , Floroglucinol/análise , Floroglucinol/isolamento & purificação , Extratos Vegetais/química , Solventes/química
3.
Molecules ; 25(24)2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33333871

RESUMO

Phloroglucinols are characteristic constituents of Hypericumjaponicum that are claimed to exert several bioactivities, such as anti-inflammatory, anti-depressant and anti-viral ones. Phloroglucinols are unstable compounds and their synthesis is challenging; thus, isolation from natural sources is still one of the main strategies for obtaining these constituents in purified form. Assessing the presence of phloroglucinols in plant materials can be of interest for compound isolation, and LC-MS approaches afford sensitivity and specificity in this regard. In this work, we combined data from quadrupole-time of flight (QTOF) and ion trap (IT) mass spectrometers in order to assess the presence of the phloroglucinols characteristic of H. japonicum and to elucidate their MS fragmentation pathways. The identified compounds present similar structures bearing the 1,3,5-trihydroxybenzene core with different substitutions, which, in constituents at higher MW, is linked to 3',3'-dimethyl-6'-oxo-phlorisobutyrophenone by a methylene bridge. Differences in MS2 spectra of the considered phloroglucinols are useful for compound identification and differentiation, and to perform dereplication studies. Overall, the proposed approach could be useful for the analysis of phloroglucinols in H. japonicum and other plant species.


Assuntos
Cromatografia Líquida , Hypericum/química , Limite de Detecção , Floroglucinol/análise , Espectrometria de Massas por Ionização por Electrospray , Floroglucinol/química
4.
Molecules ; 25(18)2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32948004

RESUMO

St. John's wort (Hypericum perforatum L.) is a medicinal plant that alleviates depression and other disorders due to its abundance of active ingredients. Hyperforin, rutin, and melatonin are the main active, and important, ingredients in St. John's wort that alleviate depression. In order to investigate the optimal conditions for accumulating these active ingredients, design of experiments and response surface methodology (RSM) was employed in this study. Two-month-old St John's wort plants were cultivated in growth chambers at varying temperatures, light intensities, and nutrient solution concentrations before analysis by HPLC, for determining differences in hyperforin, rutin, and melatonin content. The results showed that hyperforin and rutin contents were significantly influenced by temperature (18-23 °C) and light intensity (49-147 µmol m-2 s-1 photosynthetic photon flux density (PPFD)), whereas Hoagland's nutrient solution concentration (25-75%) had little effect. The accumulation of melatonin might not be influenced by cultivation conditions. Light intensity and temperature are easily controlled environmental factors in artificial cultivation, both of which are related to secondary metabolite production in the plant. Based on RSM, the optimal conditions for the accumulation of hyperforin and rutin were obtained. The maximum content of hyperforin was 5.6 mg/g, obtained at a temperature of 19 °C, a nutrient solution concentration of 45%, and a light intensity of 49 µmol m-2 s-1 PPFD. The maximum content of rutin was 3.8 mg/g obtained at a temperature of 18 °C, a nutrient solution concentration of 50%, and a light intensity of 147 µmol m-2 s-1 PPFD. This evaluation of suitable conditions for the accumulation of bioactive compounds in St. John's wort can be applied to plant factories on a large scale.


Assuntos
Hypericum/química , Luz , Nutrientes/química , Floroglucinol/análogos & derivados , Rutina/metabolismo , Terpenos/metabolismo , Cromatografia Líquida de Alta Pressão , Humanos , Hypericum/metabolismo , Melatonina/análise , Melatonina/metabolismo , Floroglucinol/análise , Floroglucinol/metabolismo , Extratos Vegetais/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Rutina/análise , Espectrofotometria Ultravioleta , Temperatura , Terpenos/análise
5.
Bol. latinoam. Caribe plantas med. aromát ; 18(5): 444-458, sept. 2019. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1008263

RESUMO

This review work focuses on how the secondary chemistry could help in the survival of plants in high mountain habitats under extreme environmental conditions. The elevated levels of stress in high areas of the tropic and subtropic change dramatically not only by following the annual cycles of winter and summer but they also change in a single day. Some species, however, are able to successfully grow at heights more than 3000 m in the tropical mountains due, in part, to highly specialized physiological processes that affect their physical and chemical responses. In this study, it describes some strategies of how the secondary metabolites could help the plants to stand the high levels of stress in the high mountain ecosystems.


Este trabajo de revisión se centra en cómo la química secundaria podría ayudar en la supervivencia de plantas en hábitats de alta montaña en condiciones ambientales extremas. Los altos niveles de estrés en las zonas altas del trópico y subtrópico cambian dramáticamente no solo al seguir los ciclos anuales de invierno y verano, sino que también cambian en un solo día. Sin embargo, algunas especies pueden crecer con éxito a alturas superiores a 3000 m en las montañas tropicales debido, en parte, a procesos fisiológicos altamente especializados que afectan sus respuestas físicas y químicas. En esta revisión, se describen algunas estrategias de cómo los metabolitos secundarios podrían ayudan a las plantas a soportar los altos niveles de estrés en los ecosistemas de alta montaña.


Assuntos
Plantas/química , Estresse Fisiológico , Óleos Voláteis/química , Altitude , Floroglucinol/análise , Floroglucinol/química , Terpenos/análise , Terpenos/química , Flavonoides/análise , Flavonoides/química
6.
J Chromatogr Sci ; 57(6): 565-574, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31209500

RESUMO

Eucalyptus barks contain complex biomass of constituents with considerable chemical and structural diversity. Reports about Eucalyptus sideroxylon Cunn. ex Woolls bark composition and biological activities are limited. Non-targeted metabolomic analysis via ultra-performance liquid chromatography-quadrupole-time-of-flight-photodiode array-mass spectrometry (UPLC-qTOF-PDA-MS) enabled first-time detection of 41 secondary metabolites of which 31 were identified including; 6 flavonoids, 4 ellagic acid derivatives, 8 triterpenes, 10 fatty acids and 3 miscellaneous. The isolation and structure elucidation of methyl morolate, ß-sitosterol, syringaldeyhde and 7'-deoxyguajavadial A were reported. The bark methylene chloride: methanol (8:2) extract demonstrated significant (P < 0.01) in vitro anti-inflammatory activity through membrane stabilization, protein denaturation inhibition, anti-lipoxygenase, and proteinase inhibition assays. The strongest anti-inflammatory activity was via membrane stabilization (34.4%) as compared to diclofenac sodium (26%) at the same concentration (125 µg/mL). Our study represents the sole complete map for E. sideroxylon bark components and represents it as new anti-inflammatory drug.


Assuntos
Anti-Inflamatórios/análise , Cromatografia Líquida de Alta Pressão/métodos , Eucalyptus/química , Floroglucinol/análise , Extratos Vegetais/química , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Membrana Eritrocítica/efeitos dos fármacos , Flavonoides/análise , Humanos , Floroglucinol/química , Floroglucinol/farmacologia , Casca de Planta/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Triterpenos/análise
7.
Molecules ; 23(12)2018 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-30572614

RESUMO

Myrtaceae are a group of plants that include a number of renowned species used in ethnomedicine in many areas worldwide. Their valuable therapeutic properties have stimulated a fruitful research activity addressed to the identification of the bioactive components of their extracts yielding a great diversity of terpenes; polyphenols; and other exclusive products. Among the latter, starting with the discovery of myrtucommulone A from myrtle (Myrtus communis), a series of structurally-related acylphloroglucinol compounds have been characterized from several species that represent the basic active principles to be considered in view of possible drug development. Aspects concerning chemical and biological properties of these products are reviewed in the present paper.


Assuntos
Myrtaceae/química , Extratos Vegetais/química , Myrtus/química , Floroglucinol/análogos & derivados , Floroglucinol/análise , Floroglucinol/química
8.
Forensic Sci Int ; 290: e1-e4, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30064830

RESUMO

In this report we describe a first suicide case in Serbia related to ingestion of Taxus baccata leaves. A 30-year old woman was found dead, and the green plant material in a plastic bag was found near her bed. Autopsy revealed dark green needle-like leaves in the stomach, similar to that contained in the plastic bag, and both were botanically identified as Taxus baccata, also known as yew. Using gas chromatography-mass spectrometry (GC-MS), 3,5-dimethoxyphenol (3,5-DMP) as toxicological evidence for the ingestion of yew leaves, was detected in biological samples. As the autopsy showed unspecific findings, and also the routine toxicological examination, based upon 3,5-DMP identification, the cause of death was determined to be suicide, caused by yew poisoning.


Assuntos
Folhas de Planta/envenenamento , Suicídio , Taxus/envenenamento , Adulto , Bile/química , Química Encefálica , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Conteúdo Gastrointestinal/química , Humanos , Rim/química , Floroglucinol/análogos & derivados , Floroglucinol/análise
9.
Mar Drugs ; 16(6)2018 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-29895761

RESUMO

The absolute configuration of retroflexanone (1) and a closely related phlorogluinol (2) was established using the advanced Mosher method and by application of HPLC-NMR. HPLC-NMR permitted a small scale Mosher method analysis to be carried out on these unstable phloroglucinols.


Assuntos
/química , Floroglucinol/análogos & derivados , Floroglucinol/química , Cromatografia Líquida de Alta Pressão/métodos , Espectroscopia de Ressonância Magnética/métodos , Estrutura Molecular , Floroglucinol/análise , Estereoisomerismo
10.
J Chem Ecol ; 44(1): 62-71, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29209932

RESUMO

Ecologists have long been interested in how the nutritional composition of leaves changes as they age, and whether this affects herbivore feeding preferences. As a consequence, the literature abounds with reports that younger leaves contain higher concentrations of nitrogen and plant secondary metabolites (PSMs) than do older leaves. Most of these studies, however, base their conclusions on average values that often mean little to herbivores. We examined this issue in the well-studied marsupial-eucalypt system, using Eucalyptus melliodora and captive common brushtail possums (Trichosurus vulpecula) offered branches from individual trees containing both young and mature leaves. Like many plants, the concentrations of N and PSMs differed among individual E. melliodora. Although young leaves were, on average, "better defended" by the PSM sideroxylonal than were mature leaves, some trees produced leaves that were relatively undefended at both ages. In response, possums chose different proportions of young and mature leaves depending on the chemistry of the individual tree. Possums did not always prefer leaves with lower concentrations of sideroxylonal (mature leaves) or those with higher concentrations of available N (young leaves). Instead, the sideroxylonal concentration of young leaves dictated their choice: possums preferred young leaves with low sideroxylonal concentrations, but not with high concentrations. By skewing their feeding toward trees producing young leaves with low concentrations of PSMs, possums may influence plant fitness. Researchers will detect these potentially important interactions only if they are aware that measuring variation among plants discloses more information than do average relationships.


Assuntos
Eucalyptus/química , Trichosurus/fisiologia , Animais , Benzofuranos/análise , Benzofuranos/farmacologia , Cromatografia Líquida de Alta Pressão , Eucalyptus/metabolismo , Comportamento Alimentar/efeitos dos fármacos , Herbivoria , Masculino , Nitrogênio/análise , Floroglucinol/análogos & derivados , Floroglucinol/análise , Floroglucinol/farmacologia , Folhas de Planta/química , Folhas de Planta/metabolismo , Fatores de Tempo
11.
Eur J Pharm Biopharm ; 126: 104-107, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28669795

RESUMO

Hyperforin is a major metabolite of the medicinal plant Hypericum perforatum (St. John's Wort) and has recently been found in hormone induced root cultures. The objective of this study is to identify a downstream process for the production of a hyperforin-rich extract with maximum extraction efficiency and minimal decomposition. The maximum extraction time was found to be 60min. The comparison of two equipment concepts for the extraction and solvent evaporation was performed employing two different solvents. While the rotary mixer showed better results for the extraction efficiency than a stirred vessel, the latter set-up was able to handle larger volumes but did not meet all process requirements. For the evaporation the prompt evaporation of the extraction agent using nitrogen stripping led to minor decomposition. In a 5L stirred vessel, the highest specific extraction of hyperforin was 4.3mg hyperforin/g dry weight bio material. Parameters for the equipment design for extraction and solvent evaporation were determined based on the experimental data.


Assuntos
Química Farmacêutica/métodos , Hypericum , Floroglucinol/análogos & derivados , Extratos Vegetais/síntese química , Raízes de Plantas , Terpenos/síntese química , Cromatografia Líquida de Alta Pressão/métodos , Floroglucinol/análise , Floroglucinol/síntese química , Floroglucinol/isolamento & purificação , Extratos Vegetais/análise , Extratos Vegetais/isolamento & purificação , Terpenos/análise , Terpenos/isolamento & purificação
12.
Microb Cell Fact ; 16(1): 187, 2017 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-29096626

RESUMO

BACKGROUND: Malonyl-coenzyme A (CoA) is an important biosynthetic precursor in vivo. Although Escherichia coli is a useful organism for biosynthetic applications, its malonyl-CoA level is too low. RESULTS: To identify strains with the best potential for enhanced malonyl-CoA production, we developed a whole-cell biosensor for rapidly reporting intracellular malonyl-CoA concentrations. The biosensor was successfully applied as a high-throughput screening tool for identifying targets at a genome-wide scale that could be critical for improving the malonyl-CoA biosynthesis in vivo. The mutant strains selected synthesized significantly higher titers of the type III polyketide triacetic acid lactone (TAL), phloroglucinol, and free fatty acids compared to the wild-type strain, using malonyl-CoA as a precursor. CONCLUSION: These results validated this novel whole-cell biosensor as a rapid and sensitive malonyl-CoA high-throughput screening tool. Further analysis of the mutant strains showed that the iron ion concentration is closely related to the intracellular malonyl-CoA biosynthesis.


Assuntos
Técnicas Biossensoriais/métodos , Malonil Coenzima A/análise , Cromatografia Líquida de Alta Pressão , Escherichia coli/genética , Escherichia coli/metabolismo , Ácidos Graxos/análise , Ácidos Graxos/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Ensaios de Triagem em Larga Escala , Malonil Coenzima A/metabolismo , Floroglucinol/análise , Floroglucinol/metabolismo , Pironas/análise , Pironas/metabolismo
13.
Molecules ; 22(9)2017 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-28891958

RESUMO

A quantitative nuclear magnetic resonance (qNMR) method to measure the content of Orlistat in tablets was studied and found to be efficient, accurate, reliable, and simple. In this paper, phloroglucinolanhydrous and dimethylsulfoxide-d6 (DMSO-d6) served as the internal standard and solvent, respectively. The qNMR methodology, including the linearity, range, the limit of detection (LOD) and quantification (LOQ), stability, precision, and accuracy, was validated seriatim, and the results were very favorable. The content determination results of three batches of Orlistat in tablets were almost identical upon comparing the qNMR method and the high-performance liquid chromatography (HPLC) method. The recommended method authentically compensated the deficiencies of the current HPLC method for determining Orlistat content, and proved to be a method complementary to traditional analysis for the purity measurement of Orlistat in some pharmaceutical preparations.


Assuntos
Fármacos Antiobesidade/análise , Lactonas/análise , Espectroscopia de Ressonância Magnética/normas , Cromatografia Líquida de Alta Pressão , Dimetil Sulfóxido/análise , Limite de Detecção , Espectroscopia de Ressonância Magnética/métodos , Orlistate , Floroglucinol/análise , Padrões de Referência , Reprodutibilidade dos Testes , Comprimidos
14.
Eur Rev Med Pharmacol Sci ; 21(8): 1990-1998, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28485775

RESUMO

OBJECTIVE: The aim of this study was to compare the pharmacokinetic characteristics of phloroglucinol between an orally disintegrating tablet and an orally lyophilized tablet of phloroglucinol in healthy volunteers under fasting condition. PATIENTS AND METHODS: A rapid and simple method based on high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method has been developed and validated for the determination of phloroglucinol in human plasma. The plasma sample was prepared by liquid-liquid extraction, and paracetamol was chosen as the internal standard. Phloroglucinol and IS were separated on a C18 column with a mobile phase consisted of methanol/water (80:20 v/v) with 0.02% formic acid. HPLC-MS/MS analyses were performed on a triple- quadruple tandem mass spectrometer by monitoring protonated parent→daughter ion pairs at m/z 125.0→56.9 for phloroglucinol, and m/z 150.2→107.0 for paracetamol (IS). The method was the high sensitivity with a lower limit of quantification (LLOQ) of 1.976 ng/mL. RESULTS: Drug and IS were detected by HPLC/MS/MS with negative electrospray ionization (ESI). Accuracy and precision for the assay were determined by calculating the intra- and inter-batch variation of quality control (QC) samples at three concentration levels. The relative standard deviation (RSD) was less than 15.0%. The detection and quantitation of drug and IS within 4.5 min make this method suitable for high-throughput analyses. In this study, the Cmax of phloroglucinol were calculated to 515.6 ± 134.4 ng/mL and 536.0 ± 144.8 ng/mL for the test drug and the reference drug, respectively. The AUC0-t values were 459.5 ± 81.03 ng·mL-1·h and 491.8 ± 95.17 ng·mL-1·h for the test drug and the reference drug; 24 subjects completed the study, respectively. The geometric mean ratio (GMR) and the 90% confidence intervals (CIs) of Cmax and AUC0-t of phloroglucinol were 97.1 (90.2-103.9) and 93.8 (88.7-99.2), respectively. CONCLUSIONS: The method was employed for the first time during pharmacokinetic studies of phloroglucinol in human plasma following a single dose of phloroglucinol 160 mg tablets. There was no significant difference in pharmacokinetic profiles between the two treatments.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Floroglucinol/análise , Espectrometria de Massas em Tandem/métodos , Voluntários Saudáveis , Humanos , Floroglucinol/farmacocinética , Equivalência Terapêutica
15.
Mycorrhiza ; 27(4): 345-354, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27999964

RESUMO

St. John's Wort (Hypericum perforatum) is a perennial herb able to produce water-soluble active ingredients (a.i.), mostly in flowers, with a wide range of medicinal and biotechnological uses. However, information about the ability of arbuscular mycorrhizal fungi (AMF) to affect its biomass accumulation, flower production, and concentration of a.i. under contrasting nutrient availability is still scarce. In the present experiment, we evaluated the role of AMF on growth, flower production, and concentration of bioactive secondary metabolites (hypericin, pseudohypericin, and hyperforin) of H. perforatum under contrasting P availability. AMF stimulated the production of aboveground biomass under low P conditions and increased the production of root biomass. AMF almost halved the number of flowers per plant by means of a reduction of the number of flower-bearing stems per plant under high P availability and through a lower number of flowers per stem in the low-P treatment. Flower hyperforin concentration was 17.5% lower in mycorrhizal than in non-mycorrhizal plants. On the contrary, pseudohypericin and hypericin concentrations increased by 166.8 and 279.2%, respectively, with AMF under low P availability, whereas no effect of AMF was found under high P availability. These results have implications for modulating the secondary metabolite production of H. perforatum. However, further studies are needed to evaluate the competition for photosynthates between AMF and flowers at different nutrient availabilities for both plant and AM fungus.


Assuntos
Flores/química , Hypericum/microbiologia , Micorrizas/fisiologia , Perileno/análogos & derivados , Floroglucinol/análogos & derivados , Terpenos/análise , Antracenos , Perileno/análise , Floroglucinol/análise , Fósforo , Extratos Vegetais
16.
J Chem Ecol ; 42(10): 1086-1097, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27577951

RESUMO

Plants are dependent on their root systems for survival, and thus are defended from belowground enemies by a range of strategies, including plant secondary metabolites (PSMs). These compounds vary among species, and an understanding of this variation may provide generality in predicting the susceptibility of forest trees to belowground enemies and the quality of their organic matter input to soil. Here, we investigated phylogenetic patterns in the root chemistry of species within the genus Eucalyptus. Given the known diversity of PSMs in eucalypt foliage, we hypothesized that (i) the range and concentrations of PSMs and carbohydrates in roots vary among Eucalyptus species, and (ii) that phylogenetic relationships explain a significant component of this variation. To test for interspecific variation in root chemistry and the influence of tree phylogeny, we grew 24 Eucalyptus species representing two subgenera (Eucalyptus and Symphyomyrtus) in a common garden for two years. Fine root samples were collected from each species and analyzed for total phenolics, condensed tannins, carbohydrates, terpenes, and formylated phloroglucinol compounds. Compounds displaying significant interspecific variation were mapped onto a molecular phylogeny and tested for phylogenetic signal. Although all targeted groups of compounds were present, we found that phenolics dominated root defenses and that all phenolic traits displayed significant interspecific variation. Further, these compounds displayed a significant phylogenetic signal. Overall, our results suggest that within these representatives of genus Eucalyptus, more closely related species have more similar root chemistry, which may influence their susceptibility to belowground enemies and soil organic matter accrual.


Assuntos
Eucalyptus/química , Eucalyptus/genética , Filogenia , Raízes de Plantas/química , Raízes de Plantas/genética , Carboidratos/análise , Fenóis/análise , Floroglucinol/análise , Taninos/análise , Terpenos/análise
17.
Anal Chim Acta ; 912: 85-96, 2016 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-26920776

RESUMO

A novel multistage MS approach, insource collision-induced dissociation (CID) combined with Time Aligned Parallel (TAP) fragmentation, was established to study the fragmentation behavior of polycyclic polyprenylated acylphloroglucinols (PPAPs), which could provide a more reliable fragmentation relationship between precursor and daughter ions. The diagnostic ions for different subtypes of PPAPs and their fragmentation behaviors have been summarized. Moreover, a new and reliable multidimensional analytical workflow that combines ultrahigh performance liquid chromatography (UHPLC), data-independent mass spectrometry (MS(E)), and tandem MS with ion mobility (IM) has been optimized and established for the analysis of PPAPs in the plant Garcinia oblongifolia by diagnostic filtering. Diagnostic fragment ions were used to selectively screen PPAPs from extracts, whereas IM coupled to MS was used to maximize the peak capacity. Under the optimized UHPLC-IM-MS(E) and UHPLC-IM-MS/MS method, 140 PPAPs were detected from the crude extract of G. oblongifolia, and 10 of them were unambiguously identified by comparing them to the reference compounds. Among those PPAPs, 7 pairs of coeluting isobaric PPAPs that were indistinguishable by conventional UHPLC-HRMS alone, were further resolved using UHPLC-IM-MS. It is anticipated that the proposed method will be extended to the rapid screening and characterization of the other targeted or untargeted compounds, especially these coeluting isomers in complex samples.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Garcinia/química , Floroglucinol/análise , Espectrometria de Massas em Tandem/métodos
18.
J Biotechnol ; 222: 47-55, 2016 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-26876610

RESUMO

Extracts of the medicinal plant Hypericum perforatum are used to treat depression and skin irritation. A major API is hyperforin, characterized by sensitivity to light, oxygen and temperature. Total synthesis of hyperforin is challenging and its content in field-grown plants is variable. We have established in vitro cultures of auxin-induced roots, which are capable of producing hyperforin, as indicated by HPLC-DAD and ESI-MS analyses. The extraction yield and the productivity upon use of petroleum ether after solvent screening were ∼5 mg/g DW and ∼50 mg/L culture after six weeks of cultivation. The root cultures also contained secohyperforin and lupulones, which were not yet detected in intact plants. In contrast, they lacked another class of typical H. perforatum constituents, hypericins, as indicated by the analysis of methanolic extracts. Hyperforins and lupulones were stabilized and enriched as dicyclohexylammonium salts. Upon up-scaling of biomass production and downstream processing, H. perforatum root cultures may provide an alternative platform for the preparation of medicinal extracts and the isolation of APIs.


Assuntos
Reatores Biológicos , Hypericum/metabolismo , Floroglucinol/análogos & derivados , Raízes de Plantas/metabolismo , Terpenos/metabolismo , Hypericum/química , Floroglucinol/análise , Floroglucinol/química , Floroglucinol/metabolismo , Extratos Vegetais , Raízes de Plantas/química , Terpenos/análise , Terpenos/química
19.
PLoS One ; 10(5): e0121584, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25938422

RESUMO

Although ecologists believe that vertebrate herbivores must select a diet that allows them to meet their nutritional requirements, while avoiding intoxication by plant secondary metabolites, this is remarkably difficult to show. A long series of field and laboratory experiments means that we have a good understanding of the factors that affect feeding by leaf-eating marsupials. This knowledge and the natural intraspecific variation in Eucalyptus chemistry allowed us to test the hypothesis that the feeding decisions of greater gliders (Petauroides volans) depend on the concentrations of available nitrogen (incorporating total nitrogen, dry matter digestibility and tannins) and of formylated phloroglucinol compounds (FPCs), potent antifeedants unique to Eucalyptus. We offered captive greater gliders foliage from two species of Eucalyptus, E. viminalis and E. melliodora, which vary naturally in their concentrations of available nitrogen and FPCs. We then measured the amount of foliage eaten by each glider and compared this with our laboratory analyses of foliar total nitrogen, available nitrogen and FPCs for each tree offered. The concentration of FPCs was the main factor that determined how much gliders ate of E. viminalis and E. melliodora, but in gliders fed E. viminalis the concentration of available nitrogen was also a significant influence. In other words, greater gliders ate E. viminalis leaves with a particular combination of FPCs and available nitrogen that maximised the nutritional gain but minimised their ingestion of toxins. In contrast, the concentration of total nitrogen was not correlated with feeding. This study is among the first to empirically show that browsing herbivores select a diet that balances the potential gain (available nutrients) and the potential costs (plant secondary chemicals) of eating leaves. The major implication of the study is that it is essential to identify the limiting nutrients and relevant toxins in a system in order to understand feeding behaviour.


Assuntos
Comportamento Alimentar , Alimentos , Marsupiais/fisiologia , Toxinas Biológicas/análise , Animais , Feminino , Masculino , Nitrogênio/análise , Floroglucinol/análise , Folhas de Planta/química
20.
Phytother Res ; 29(7): 1097-101, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25851311

RESUMO

Hypericum perforatum is a medicinal plant with anti-inflammatory and antioxidant properties, which is commercially available for therapeutic use in Brazil. Herein the effect of H. perforatum extract on paracetamol (acetaminophen)-induced hepatotoxicity, lethality, inflammation, and oxidative stress in male swiss mice were investigated. HPLC analysis demonstrated the presence of rutin, quercetin, hypericin, pseudohypericin, and hyperforin in H. perforatum extract. Paracetamol (0.15-3.0 g/kg, p.o.) induced dose-dependent mortality. The sub-maximal lethal dose of paracetamol (1.5 g/kg, p.o.) was chosen for the experiments in the study. H. perforatum (30-300 mg/kg, i.p.) dose-dependently reduced paracetamol-induced lethality. Paracetamol-induced increase in plasma aspartate aminotransferase (AST) and alanine aminotransferase (ALT) concentrations, and hepatic myeloperoxidase activity, IL-1ß, TNF-α, and IFN-γ concentrations as well as decreased reduced glutathione (GSH) concentrations and capacity to reduce 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonate radical cation; ABTS˙(+) ) were inhibited by H. perforatum (300 mg/kg, i.p.) treatment. Therefore, H. perforatum protects mice against paracetamol-induced lethality and liver damage. This effect seems to be related to the reduction of paracetamol-induced cytokine production, neutrophil recruitment, and oxidative stress.


Assuntos
Acetaminofen/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Hypericum/química , Inflamação/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Alanina Transaminase/sangue , Animais , Antracenos , Anti-Inflamatórios/farmacologia , Antioxidantes/uso terapêutico , Aspartato Aminotransferases/sangue , Glutationa/metabolismo , Masculino , Camundongos , Perileno/análogos & derivados , Perileno/análise , Floroglucinol/análogos & derivados , Floroglucinol/análise , Plantas Medicinais/química , Quercetina/análise , Rutina/análise , Terpenos/análise , Fator de Necrose Tumoral alfa/metabolismo
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