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1.
Phytochem Anal ; 33(8): 1190-1197, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35999031

RESUMEN

INTRODUCTION: Capillary zone electrophoresis with direct UV detection (CZE-UV) was used to investigate the hypothesis about the extract of Baccharis trimera enzymatic activities as an analytical approach to monitoring the phenomenon. OBJECTIVE: The aim of this work was to investigate enzymatic bioactivities of the hydroalcoholic and infusion extracts of B. trimera through screening evaluation of the inhibition of the enzymes acetylcholinesterase (AChE) and α-glycosidase (α-GLY). METHOD: An alternative approach using CZE-UV to hydroalcoholic and infusion extracts of B. trimera monitoring was applied to evaluate the inhibition ability of the enzymes AChE and α-GLY. The result of the reaction of acetylthiocholine (AThCh) with AChE was thiocholine (TCh) and acetic acid, and from the amount of TCh generated, the AChE inhibition was calculated. For the inhibition study of the two enzymes, the reactions of the extracts were optimised to be performed in situ, inside the capillary column, and the introduction of the solutions was performed through ordered sequential plug injections. RESULTS: Samples extracted with 70% ethanol presented 7.80% inhibition for AChE and 0.51% for α-GLY, while samples extracted with 96% ethanol resulted in 6.89% inhibition for AChE and no inhibition activity for α-GLY. CONCLUSION: In the present work, the potentialities of CZE-UV for the study of hydroalcoholic and infusion extracts of B. trimera were demonstrated. The experimental results were useful for the calculation of the percentage of the inhibition activities of the AChE and α-GLY enzymes.


Asunto(s)
Baccharis , Acetilcolinesterasa , Extractos Vegetales/farmacología , Etanol , Ácido Acético
2.
J Org Chem ; 84(15): 9684-9692, 2019 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-31283216

RESUMEN

The study of host-guest complexation between reactive 2-carboxyphthalanilic acid (CPA) and two cationic pillararenes has been carried out. Host-guest complexation with significant kinetic effects was observed only with the smaller cavity size pillararene (P5A). Kinetics in the pH range 1.50-6.40, ESI-MS, 1H NMR titration, and ROESY experiments were performed to characterize the complexes. High binding stoichiometry (H:G2) was observed for all CPA protonation states. The system is pH-dependent, and inversion of cooperativity (negative to positive) occurs by increasing the dianionic CPA2- concentration (allosteric behavior). Toward physiological pH, association constant K1:1 does not change (104 M-1), and K1:2 increased from 102 to 104 M-1, as well as the inhibitory effect increased up to 222-fold. NMR results elucidated the structure of the complex and allowed us to create a map of H-H interactions that describes well the diversity and number of interactions in the complex.

3.
Anal Bioanal Chem ; 409(7): 1943-1950, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27988799

RESUMEN

This paper reports the development of a fast separation method employing capillary zone electrophoresis for the simultaneous determination of hippuric acid, mandelic acid, and creatinine in samples of urine using a coated capillary. The background electrolyte was composed of 10 mmol L-1 tris(hydroxymethyl)aminomethane and 30 mmol L-1 2-hydroxy-isobutyric acid at pH 3.6. The internal standard was 3,5-dihydroxybenzoic acid. Separations were performed in a fused silica capillary (32 cm total length, 8.5 cm effective length, and 50 µm internal diameter) coated with crosslinked hydroxypropyltrimethyl ammonium chloride chitosan and κ-carrageenan. Direct UV detection was performed at a wavelength of 200 nm. Samples and standards were injected hydrodynamically (-50 mbar, 3 s) using the short-end injection procedure. The electrophoretic system was operated under constant voltage of 30 kV with positive polarity on the injection side. The separation time for hippuric acid, mandelic acid, and creatinine was less than 70 s. The evaluation of some analytical parameters of the method for the three analytes showed good linearity (R 2 > 0.99), limit of detections of 0.21 to 0.63 mg L-1, inter-day precision better than 3.0% (peak area), and recovery in the range of 98 to 106%. The method developed was applied in the analysis of the three analytes in urine samples. Graphical Abstract New method using capillary zone electrophoresis for analysis of creatinine, hippuric acid and mandelic acid in urine.


Asunto(s)
Creatinina/orina , Electroforesis Capilar/métodos , Hipuratos/orina , Ácidos Mandélicos/orina , Polímeros/química
4.
An Acad Bras Cienc ; 89(3): 1907-1915, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28767890

RESUMEN

Many essential oils (EOs) of different plant species possess interesting antimicrobial effects on buccal bacteria and antioxidant properties. Eugenia klotzschiana Berg (pêra-do-cerrado, in Portuguese) is a species of Myrtaceae with restricted distribution in the Cerrado. The essential oils were extracted through the hydrodistillation technique using a modified Clevenger apparatus (2 hours) and chemically characterized by GC-MS. The major compounds were α-copaene (10.6 %) found in oil from leaves in natura, ß-bisabolene (17.4 %) in the essential oil from dry leaves and α-(E)-bergamotene (29.9 %) in oil from flowers. The antioxidant activity of essential oils showed similarities in both methods under analysis (DPPH and ABTS˙+) and the results suggested moderate to high antioxidant activity. The antibacterial activity was evaluated by determining minimum inhibitory concentrations (MICs), using the microdilution method. MIC values below 400 µg/mL were obtained against Streptococcus salivarius (200 µg/mL), S. mutans (50 µg/mL), S. mitis (200 µg/mL) and Prevotella nigrescens (50 µg/mL). This is the first report of the chemical composition and antibacterial and antioxidant activities of the essential oils of E. klotzschiana. These results suggest that E. klotzschiana, a Brazilian plant, provide initial evidence of a new and alternative source of substances with medicinal interest.


Asunto(s)
Antibacterianos/farmacología , Antioxidantes/farmacología , Eugenia/química , Flores/química , Hojas de la Planta/química , Prevotella/efectos de los fármacos , Streptococcus/efectos de los fármacos , Antibacterianos/aislamiento & purificación , Antioxidantes/aislamiento & purificación , Cromatografía de Gases y Espectrometría de Masas , Pruebas de Sensibilidad Microbiana
5.
Chirality ; 27(11): 788-94, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26377753

RESUMEN

A superficially porous particle (SPP)-based hydroxypropyl-ß-cyclodextrin (HPBCD) chiral stationary phase (CSP) was produced and its chromatographic performance was compared to both 5 µm and 3 µm fully porous particle (FPP)-based CSPs. The relative surface coverage of the HPBCD chiral selector on each particle was approximately equal, which resulted in equivalent enantiomeric selectivity (α) values on each phase when constant mobile phase conditions were used. Under such conditions, the SPP column resulted in greatly reduced analysis times and three times greater efficiencies compared to the FPP columns. When higher flow rates were used, efficiency gains per analysis times were five times greater for the SPP column compared to the FPP-based columns. When the mobile phases were altered to give similar analysis times on each column, resolution values were doubled for the SPP column. Finally, the novel SPP based HPBCD column proved to be stable for 500 injections under high flow rate (4.5 mL/min) and high pressure (400 bar) conditions used for an ultrafast (~45 sec) enantiomeric separation.

6.
Langmuir ; 28(3): 1758-64, 2012 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-22176674

RESUMEN

Addition of salts, especially perchlorates, to zwitterionic micelles of SB3-14, C(14)H(29)NMe(2)(+)(CH(2))(3)SO(3)(-), induces anionic character and uptake of H(3)O(+) by SB3-14 micelles. Thus, the addition of alkali metal perchlorates accelerates the acid hydrolysis of 2-(p-heptoxyphenyl)-1,3-dioxolane, HPD, in the presence of SB3-14 micelles, which depends on the local proton concentration at the micelle surface. The addition of metal chlorides to solutions of such perchlorate-modified SB3-14 micelles decreases both the negative zeta potential of the micelles and the observed rate constant for acid hydrolysis of HPD. The effect of the monovalent cations Li(+), Na(+), and K(+) is smaller than that of the divalent cations Be(2+), Mg(2+), and Ca(2+), and much smaller than that of the trivalent cations Al(3+), La(3+), and Er(3+). The major factor responsible for this cation valence dependence of these effects is shown to be electrostatic in nature, reflecting the strong dependence of the micellar surface potential on the cation valence. The fact that the salt effects are not identical after correction for the electrostatic effects indicates that additional secondary nonelectrostatic effects may contribute as well.

7.
J Org Chem ; 77(23): 10907-13, 2012 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-23167539

RESUMEN

This work presents a detailed kinetic and mechanistic study of biologically interesting dephosphorylation reactions involving the exceptionally reactive nucleophilic group, hydroxamate. We compare results for hydroxamate groups anchored on the simple molecular backbone of benzohydroxamate (BHA) and on the more complex structure of the widely used drug, deferoxamine (DFO). BHA shows extraordinary reactivity toward the triester diethyl 2,4-dinitrophenyl phosphate (DEDNPP) and the diester ethyl 2,4-dinitrophenyl phosphate (EDNPP) but reacts very slowly with the monoester 2,4-dinitrophenyl phosphate (DNPP). Nucleophilic attack on phosphorus is confirmed by the detection of the phosphorylated intermediates formed. These undergo Lossen-type rearrangements, resulting in the decomposition of the nucleophile. DFO, which is used therapeutically for the treatment of acute iron intoxication, carries three hydroxamate groups and shows correspondingly high nucleophilic activity toward both triester DEDNPP and diester EDNPP. This result suggests a potential use for DFO in cases of acute poisoning with phosphorus pesticides.


Asunto(s)
2,4-Dinitrofenol/análogos & derivados , Deferoxamina/química , Ácidos Hidroxámicos/química , Organofosfatos/química , Compuestos Organoplatinos/química , Plaguicidas/química , Fosfatos/química , 2,4-Dinitrofenol/química , Hidrólisis , Cinética , Espectroscopía de Resonancia Magnética , Estructura Molecular , Compuestos Organoplatinos/envenenamiento , Plaguicidas/envenenamiento , Fosforilación
8.
Plant Cell Rep ; 31(12): 2165-76, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22865112

RESUMEN

UNLABELLED: DNA methylation is an epigenetic regulatory mechanism of gene expression which can be associated with developmental phases and in vitro morphogenetic competence in plants. The present work evaluated the effects of 5-azacytidine (AzaC) and 2,4-dichlorophenoxyacetic acid (2,4-D) on Acca sellowiana somatic embryogenesis (SE) and global DNA methylation levels by high-performance liquid chromatography mass spectrometry (HPLC/MS/MS). 2,4-D-free treatments revealed no somatic embryo formation in both accessions tested. Treatments supplemented with 2,4-D pulse plus AzaC in the culture medium resulted in increased embryo formation. In AzaC-free treatment, HPLC/MS/MS analysis showed a gradual increase in methylation levels in cultures of both accessions tested during SE induction. Treatment with AzaC and 2,4-D-free resulted in a marked decrease in methylation for both accessions, ranging from 37.6 to 20.8 %. In treatment with 2,4-D and AzaC combined, the 85 accession showed increasing global methylation levels. Otherwise, the 101X458 accession, in the same treatment, showed a decrease between 10 and 20 days, followed by an increase after 30 days (39.5, 36.2 and 41.6 %). These results indicate that 2,4-D pulse combined with AzaC improves SE induction. However, the conversion phase showed that although positively influencing SE induction, AzaC had a dysregulatory effect on the stage of autotrophic plant formation, resulting in significantly lower conversion rates. The results suggest that DNA methylation dramatically influences SE in Acca sellowiana, and global DNA methylation dynamics are related to morphogenetic response. KEY MESSAGE: 5-Azacytidine combined with 2,4-D increases the number of Acca sellowiana somatic embryos. Global DNA methylation is directly affected by these compounds.


Asunto(s)
Ácido 2,4-Diclorofenoxiacético/farmacología , Azacitidina/farmacología , Metilación de ADN , Feijoa/efectos de los fármacos , Técnicas de Embriogénesis Somática de Plantas/métodos , Semillas/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Medios de Cultivo/metabolismo , ADN de Plantas/genética , ADN de Plantas/metabolismo , Epigénesis Genética , Feijoa/embriología , Feijoa/genética , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Espectrometría de Masas , Semillas/embriología , Semillas/genética
9.
J Cosmet Sci ; 62(5): 469-82, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22152492

RESUMEN

Our goal was to study the effect of Gp4G on skin tissues and unravel its intracellular action mechanisms. The effects of Gp4G formulation, a liposomic solution of Artemia salina extract, on several epidermal, depmal, and hair follicle structures were quantified. A 50% increase in hair length and a 30% increase in the number of papilla cells were explained by the changes in the telogen/anagen hair follicle phases. Increasing skin blood vessels and fibroblast activation modified collagen arrangement in dermal tissues. Imunohistochemical staining revealed expressive increases of versican (VER) deposition in the treated animals (68%). Hela and fibroblast cells were used as in vitro models. Gp4G enters both cell lines, with a hyperbolic saturation profile inducing an increase in the viabilities of Hela and fibroblast cells. Intracellular ATP and other nucleotides were quantified in Hela cells showing a 38% increase in intracellular ATP concentration and increases in the intracellular concentration of tri- , di- , and monophosphate nucleosides, changing the usual quasi-equilibrium state of nucleotide concentrations. We propose that this change in nucleotide equilibrium affects several biochemical pathways and explains the cell and tissue activations observed experimentally.


Asunto(s)
Fosfatos de Dinucleósidos/farmacología , Folículo Piloso/efectos de los fármacos , Preparaciones para el Cabello/farmacología , Animales , Artemia , Células Epiteliales/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Cabello/efectos de los fármacos , Cabello/crecimiento & desarrollo , Folículo Piloso/crecimiento & desarrollo , Células HeLa/efectos de los fármacos , Humanos , Masculino , Ratones , Modelos Animales , Ratas , Ratas Wistar , Piel/citología , Piel/efectos de los fármacos
10.
Talanta ; 235: 122820, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34517675

RESUMEN

This paper presents the Outer Plug Standardization - OPS, a novel technique as an alternative for the classic internal standardization using multiple injection in capillary zone electrophoresis is proposed herein. This technique was applied in a new method for the determination of chloride, nitrate and sulfate in rainwater samples. After the injection accuracy was tested and proved to be a minor error source (average 1.26% RSD), the OPS was applied and it improved the intra-day and inter-day precision of the analytical method by 32.5% and 24.7%, respectively. Using a capillary with effective length of 23.5 cm the electrophoretic separation of the three inorganic anions could be achieved in <1 min, with detection limits of 0.05, 0.09 and 0.11 mg L-1 for chloride, nitrate and sulfate, respectively. Also, the statistical t-test was applied to the results obtained for 82 rainwater samples that were collected and analyzed applying both the method developed in this study and the official APHA 4140 method where no statistical difference was noted within a 95% confidence level.


Asunto(s)
Cloruros , Proyectos de Investigación , Aniones , Calibración , Estándares de Referencia
11.
Langmuir ; 26(2): 1008-12, 2010 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-19711953

RESUMEN

Hexadecyl phosphorylcholine (HPC) micelles incorporate anions rather than cations in the interfacial region, giving an anionoid micelle with a negative zeta potential. Hydronium ion incorporation in the micellar pseudophase parallels the increase in the negative zeta potential, and salts increase the rate of A1 hydrolysis of 2-(p-heptyloxyphenyl)-1,3-dioxolane in micellized HPC and inhibit the reaction of OH(-) with naphthoic anhydride. The kinetic effects are larger with NaClO(4) than with NaCl. The increased micellar negative charge with added salts increases the repulsion between headgroups and decreases the aggregation number. These observations are relevant to understanding the behaviors of biological phosphorylcholine amphiphiles.

12.
Langmuir ; 26(20): 15754-60, 2010 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-20849116

RESUMEN

Synthesis of a new zwitterionic surfactant containing the imidazolium ring 3-(1-tetradecyl-3-imidazolio)propanesulfonate (ImS3-14) is described. The solubility of ImS3-14 is very low but increases on addition of a salt which helps to stabilize the micellized surfactant. Fluorescence quenching and electrophoretic evidence for ImS3-14 shows that the micellar aggregation number is only slightly sensitive to added salts, as is the critical micelle concentration, but NaClO(4) markedly increases zeta potentials of ImS3-14 in a similar way as in N-tetradecyl-N,N-dimethylammonio-1-propanesulfonate (SB3-14) micelles. The rate of specific hydrogen ion catalyzed hydrolysis of 2-(p-heptoxyphenyl)-1,3-dioxolane and equilibrium protonation of 1-hydroxy-2-naphthoate ion in zwitterionic micelles of ImS3-14 and SB3-14 are increased markedly by NaClO(4) which induces anionoid character and uptake of H(3)O(+), but NaCl is much less effective in this respect. Comparison of ImS3-14 with SB3-14 is based on experimental evidence, and computational calculations indicate similarities and differences in structures of both compounds.

13.
Spectrochim Acta A Mol Biomol Spectrosc ; 243: 118773, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-32846407

RESUMEN

The chemical analysis of archaeological ceramic artifacts can help archaeologists to characterize the technology used in the manufacturing process, and to elucidate aspects related to the way of life of past peoples. In this context, six ceramic fragments found at Tapera Beach in Florianópolis were analyzed. FTIR spectroscopy was used to identify carbonates and oxalic acid originating from the biodegradation process. In the pictorial regions of the ceramics, iron oxides, manganese and chromium were present, along with calcium carbonate, which were used as pigments. In addition, the absence of characteristic bands for kaolinite suggests low firing temperatures (up to 900 °C). EDS confirmed the elements of the molecules identified by FTIR and showed the presence of Al and Si in the primary structure and Fe in the secondary structure of the ceramics. In addition, there were traces of rare earth elements in samples A3 and A5, which may be related to the geochemistry at the site from which the raw material was excavated. The GC-MS results showed the presence of lipids and the profile of the fatty acids detected suggested that the source of the oils adsorbed in the ceramic structure is vegetable.

14.
J Neuroimmunol ; 340: 577145, 2020 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-31945593

RESUMEN

Lavandula angustifolia (LaEO) essential oil has been widely used by aromatherapy in the treatment of various clinical conditions, with evidence of its analgesic and anti-inflammatory potential. Our results demonstrate that sixty-five substances were identified in LaEO. Among the compounds found, the major ones were linalool (30.61%) and linalyl acetate (20.36%). We found that LaEO inhalation reduces mechanical hyperalgesia in conditions of chronic inflammatory and neuropathic pain. Furthermore, this effect seems to be mediated by peripheral and central opioid and cannabinoid 2 receptors. The findings of the present study suggests that the LaEO inhalation is effective on the chronic pain treatment.


Asunto(s)
Hiperalgesia , Aceites Volátiles/farmacología , Receptores de Cannabinoides/metabolismo , Receptores Opioides/metabolismo , Animales , Modelos Animales de Enfermedad , Femenino , Hiperalgesia/metabolismo , Inflamación/metabolismo , Lavandula , Ratones , Neuralgia/metabolismo , Extractos Vegetales/farmacología
15.
J Sep Sci ; 32(21): 3822-8, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19877139

RESUMEN

A method for the simultaneous determination of the stilbene resveratrol, four phenolic acids (syringic, coumaric, caffeic, and gallic acids), and five flavonoids (catechin, rutin, kaempferol, myricetin, and quercetin) in wine by CE was developed and validated. The CE electrolyte composition and instrumental conditions were optimized using 2(7-3) factorial design and response surface analysis, showing sodium tetraborate, MeOH, and their interaction as the most influential variables. The optimal electrophoretic conditions, minimizing the chromatographic resolution statistic values, consisted of 17 mmol/L sodium tetraborate with 20% methanol as electrolyte, constant voltage of 25 kV, hydrodynamic injection at 50 mbar for 3 s, and temperature of 25 degrees C. The R(2) values for linearity varied from 0.994 to 0.999; LOD and LOQ were 0.1 to 0.3 mg/L and 0.4 to 0.8 mg/L, respectively. The RSDs for migration time and peak area obtained from ten consecutive injections were less than 2% and recoveries varied from 97 to 102%. The method was applied to 23 samples of inexpensive Brazilian wines, showing wide compositional variation.


Asunto(s)
Electroforesis Capilar/métodos , Flavonoides/análisis , Hidroxibenzoatos/análisis , Fenoles/análisis , Vino/análisis , Brasil , Límite de Detección , Polifenoles , Reproducibilidad de los Resultados , Resveratrol , Estilbenos/análisis
16.
J Phys Chem B ; 112(46): 14373-8, 2008 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-18582111

RESUMEN

The rate of specific hydrogen ion-catalyzed hydrolysis of 2-( p-heptoxyphenyl)-1,3-dioxolane and acid-base equilibrium of 4-carboxy-1-n-dodecylpyridinium in zwitterionic micelles of SB3-14, C14H29NMe2+(CH2)3SO3(-) are controlled by NaClO4, which induces anionic character and uptake of H3O+ in the micelles. Other salts, e.g., NaF, NaCl, NaBr, NaNO3, NaI, NaBF4, have similar, but smaller, effects on the uptake of H3O+. Salt effects upon zeta potentials of SB3-14 micelles, estimated by capillary electrophoresis, are anion specific, and the anion order is similar to that of the rates of acid hydrolysis and of acid-base equilibria. Fluorescence quenching shows that the micellar aggregation number is not very sensitive to added salts, consistent with electrophoretic evidence. These specific anion effects follow the Hofmeister series and are related to anion hydration free energies.


Asunto(s)
Aniones/química , Betaína/análogos & derivados , Cationes/química , Micelas , Betaína/química , Electroforesis Capilar , Electricidad Estática
17.
J Chromatogr A ; 1204(1): 123-7, 2008 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-18691716

RESUMEN

The aim of this study was to develop a fast capillary electrophoresis method for the determination of benzoate and sorbate ions in commercial beverages. In the method development the pH and constituents of the background electrolyte were selected using the effective mobility versus pH curves. As the high resolution obtained experimentally for sorbate and benzoate in the studies presented in the literature is not in agreement with that expected from the ionic mobility values published, a procedure to determine these values was carried out. The salicylate ion was used as the internal standard. The background electrolyte was composed of 25 mmol L(-1) tris(hydroxymethyl)aminomethane and 12.5 mmol L(-1) 2-hydroxyisobutyric acid, at pH 8.1. Separation was conducted in a fused-silica capillary (32 cm total length and 8.5 cm effective length, 50 microm I.D.), with short-end injection configuration and direct UV detection at 200 nm for benzoate and salicylate and 254 nm for sorbate ions. The run time was only 28s. A few figures of merit of the proposed method include: good linearity (R(2)>0.999), limit of detection of 0.9 and 0.3 mg L(-1) for benzoate and sorbate, respectively, inter-day precision better than 2.7% (n=9) and recovery in the range 97.9-105%. Beverage samples were prepared by simple dilution with deionized water (1:11, v/v). Concentrations in the range of 197-401 mg L(-1) for benzoate and 28-144 mg L(-1) for sorbate were found in soft drinks and tea.


Asunto(s)
Benzoatos/análisis , Bebidas/análisis , Electroforesis Capilar/métodos , Ácido Sórbico/análisis , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
18.
J Chromatogr A ; 1570: 148-154, 2018 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-30098731

RESUMEN

A novel method for the sequential determination of sodium, potassium, calcium, and magnesium and free and total glycerol in biodiesel by capillary zone electrophoresis is proposed herein. The inorganic cations were separated along an effective length of 43.5 cm. The samples to quantify the free and total glycerol were injected into the opposite capillary end, close to the detection window, with an effective length of 8.5 cm. It was possible to achieve the separation of six analytes within 3 min. The quantification limits for the cations and glycerol ranged from 0.071 to 0.5 mg kg-1 to and 0.0017% to 0.017% w/w, respectively. Despite the complexity of the injection steps, the values for the instrumental, intraday and interday precision were better than 2.13, 4.49 and 5.68% (RSD), respectively, for the cations and the free and total glycerol. The method has good accuracy and specificity, which was statistically confirmed through an interlaboratory assay, where the method was compared with official methods.


Asunto(s)
Biocombustibles/análisis , Calcio/análisis , Electroforesis Capilar/métodos , Glicerol/análisis , Magnesio/análisis , Potasio/análisis , Sodio/análisis
19.
J Ethnopharmacol ; 217: 178-186, 2018 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-29462700

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Eugenia brasiliensis Lam. (Myrtaceae) is a Brazilian tree distributed throughout Atlantic rain forest, since Bahia until Santa Catarina state, and is popularly known as "grumixaba, grumixameira, cumbixaba, ibaporoiti, and cereja-brasileira". The bark and leaves of Eugenia brasiliensis are used in folk medicine as adstringent, diuretic, energizing, anti-rheumatic and anti-inflammatory. This study aimed at investigating the chemical composition, antinociceptive and anti-inflammatory effect of the hydroalcoholic extract of Eugenia brasiliensis (HEEb). MATERIAL AND METHODS: Chemical composition of the HEEb was determined by High Performance Liquid Chromatography/ESI-Mass Spectrometry (HPLC-ESI-MS/MS). The antinociceptive and anti-inflammatory effects of HEEb (30-300 mg/kg) was verified in mice after oral administration by intra-gastric gavage (i.g.) 60 min prior to experimentation. It was investigated whether HEEb decreases visceral pain and leukocyte migration induced by an intraperitoneal (i.p.) injection of acetic acid (0.6%). We also evaluated whether HEEb decreases nociceptive behavior induced by formalin (including paw edema and temperature), prostaglandin E2 (PGE2), histamine, and compound 48/80. Finally, we evaluated the effect of HEEb in the chronic inflammatory (mechanical and thermal hypersensitivity) pain induced by complete Freund's adjuvant (CFA), as well as quantifying the concentration of the pro-inflammatory cytokines TNF-α and IL-6 in the paw by ELISA method. RESULTS: Seven polyphenols were identified in HEEb by HPLC-ESI-MS/MS analysis. HEEb treatment alleviated nocifensive behavior and leukocyte migration caused by acetic acid. Moreover, HEEb also reduced the inflammatory pain and paw temperature induced by formalin, as well as it decreased nociceptive behavior induced by histamine and compound 48/80. Finally, acute and repeated treatment of animals with HEEb (100 mg/kg, i.g.) markedly reduced the mechanical and thermal (heat) hypersensitivity, besides decrease paw edema and temperature induced by CFA, and this effect was evident until the day 7. Moreover, repeated treatment with HEEb (100 mg/kg, i.g.) significantly reduced the levels of IL-6 and TNF-α in the paw when compared to the CFA group. CONCLUSIONS: This is the first report showing that HEEb presents antinociceptive and anti-inflammatory effects in the visceral and somatic inflammatory pain in mice, possibly involving the inhibition of histamine receptors and pro-inflammatory cytokines activated pathways. Our results are of interest because they support the use of Eugenia brasiliensis as a potential source of phytomedicine for inflammatory diseases and pain.


Asunto(s)
Analgésicos/farmacología , Antiinflamatorios/farmacología , Eugenia , Dolor Nociceptivo/prevención & control , Extractos Vegetales/farmacología , Dolor Visceral/prevención & control , Analgésicos/aislamiento & purificación , Animales , Antiinflamatorios/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Eugenia/química , Femenino , Mediadores de Inflamación/metabolismo , Interleucina-6/metabolismo , Ratones , Dolor Nociceptivo/inducido químicamente , Dolor Nociceptivo/metabolismo , Fitoterapia , Extractos Vegetales/aislamiento & purificación , Plantas Medicinales , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masas en Tándem , Factor de Necrosis Tumoral alfa/metabolismo , Dolor Visceral/inducido químicamente , Dolor Visceral/metabolismo
20.
Food Chem Toxicol ; 118: 557-565, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29886231

RESUMEN

Antiinflammatory and antitumor activity has been reported in Passiflora edulis (yellow passion fruit) nevertheless the intrinsic mechanisms of action are not fully elucidated. The present study aimeds to perform a comparison between the antitumor activity involving the crude extract (HCE) and the supercritical fluid extract with ethanol as co-solvent (SFEtOH) from P. edulis f. flavicarpa Deg. The in vitro cytotoxicity was evaluated in MCF-7 cells, while the in vivo antitumor activity was assessed in male Balb/c mice inoculated with Ehrlich carcinoma cells. SFEtOH exhibited higher antitumor activity compared to HCE. Wherein, SFEtOH showed an EC50 of 264.6 µg/mL against MCF-7 cells as well as an increased inhibition of tumor growth of 48.5% (p < 0.001) in male Balb/c mice, thereby promoting an increased mice lifespan to approximately 42%. Moreover, SFEtOH caused lipid (p < 0.001) and protein (p < 0.001) oxidation by increasing glutathione redox cycle activity while decreased the thioredoxin reductase activity (p < 0.001). SFEtOH also induced oxidative DNA damage in Ehrlich ascites carcinoma (EAC) cells leading to G2/M cycle arrest and has increased apoptotic cells up to 48.2%. These data suggest that the probable mechanisms of antitumor effect are associated to the lipid, protein and DNA damage, leading to cell cycle arrest and triggering apoptosis via mitochondrial pathway, should be probable due to the presence of medium and long chain fatty acids such as lauric acid.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Ácidos Grasos/metabolismo , Estrés Oxidativo , Passiflora/química , Animales , Antineoplásicos Fitogénicos/aislamiento & purificación , Biomarcadores , Ensayos de Selección de Medicamentos Antitumorales , Cromatografía de Gases y Espectrometría de Masas , Humanos , Células MCF-7 , Masculino , Ratones Endogámicos BALB C , Ensayos Antitumor por Modelo de Xenoinjerto
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