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1.
Molecules ; 26(6)2021 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-33805790

RESUMO

A highly specific and sensitive proton nuclear magnetic resonance (1H-NMR) method has been developed for the quantification of ephedrine alkaloid derivatives in Ephedra herbal commercial prescriptions. At the region of δ 4.0 to 5.0 ppm in the 1H NMR spectrum, the characteristic signals are separated well from each other, and six analogues in total, methylephedrine (ME), ephedrine (EP), norephedrine (NE), norpseudoephedrine (NP), pseudoephedrine (PE), and methylpseudoephedrine (MP) could be identified. The quantities of these compounds are calculated by the relative ratio of the integral values of the target peak for each compound to the known concentrations of the internal standard anthracene. The present method allows for a rapid and simple quantification of ephedrine alkaloid derivatives in Ephedra-related commercial prescriptions without any preliminary purification steps and standard compounds, and accordingly it can be a powerful tool to verify different Ephedra species. In comparison to conventional chromatographic methods, the advantages of this method include the fact that no standard compounds are required, the quantification can be directly performed on the crude extracts, a better selectivity for various ephedrine alkaloid derivatives, and the fact that a very significant time-gain may be achieved.


Assuntos
Alcaloides/análise , Ephedra/química , Efedrina/análogos & derivados , Efedrina/análise , Ephedra/classificação , Estudos de Viabilidade , Humanos , Limite de Detecção , Espectroscopia de Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/estatística & dados numéricos , Medicina Tradicional Chinesa , Fenilpropanolamina/análise , Preparações de Plantas/química , Pseudoefedrina/análise , Especificidade da Espécie
2.
Forensic Sci Int ; 319: 110658, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33370655

RESUMO

The consumption of Khat leaves represents an ancient kind of drug abuse mainly observed in Eastern Africa and the Arab Peninsula among adult men. For this purpose, the leaves are directly collected from the shrub "Catha edulis" prior to extensive chewing process. Seizures in Europe are rare, since the leaves have to undergo quick transportation: After a short period of time, the harvested leaves decompose and suffer in decrease of concentration of the active ingredient cathinone, which makes long term transportation difficult. As an alternative, plant material can be dried to increase life period. In the past years, an increasing number of seizures were made by Austrian police, however, the content of cathinone and cathine in dry material is widely unknown. In this work, a seizure of fresh Khat leaves was compared with two seizures of dried material in terms of concentration of cathinone and cathine using LC-MS/MS analysis. For fresh leaves, a purity grade was found to be 0.115-0.158% for cathinone and 0.172-0.192% for cathine, respectively. In contrast, subsequent storage of dried Khat leaves over months led to a dramatic loss of cathinone: Analysis of two seizures revealed that concentration of cathinone dropped to 0.021-0.023%. These findings are intended to serve as a guideline for Justice authorities to estimate the content of the controlled ingredients of Khat leaves in future.


Assuntos
Alcaloides/análise , Catha/química , Dessecação , Fenilpropanolamina/análise , Folhas de Planta/química , Cromatografia Líquida , Humanos , Transtornos Relacionados ao Uso de Substâncias , Espectrometria de Massas em Tandem
3.
J Chromatogr A ; 1623: 461176, 2020 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-32505280

RESUMO

A detailed computer simulation study of the isotachophoretic migration and separation of norpseudoephedrine stereoisomers for cases with the neutral selector added to the leader, immobilized to the capillary wall or support, or partially present in the separation column is presented. The electrophoretic transport of the analytes from the sampling compartment into the separation medium with the selector, the formation of a transient mixed zone, the separation dynamics of the stereoisomers with a free or immobilized selector, the dependence of the leader pH, the ionic mobility of norpseudoephedrine, the complexation constant and selector immobilization on steady-state plateau zone properties, and zone changes occurring during the transition from the chiral environment into a selector free leader are thereby visualized in a hitherto unexplored way. For the case with the selector dissolved in the leading electrolyte, simulation data are compared to those observed in experimental setups with coated fused-silica capillaries that feature minimized electroosmosis and zone detection with conductivity and absorbance detectors.


Assuntos
Isotacoforese , Fenilpropanolamina/química , Simulação por Computador , Eletro-Osmose , Fenilpropanolamina/análise , Fenilpropanolamina/isolamento & purificação , Dióxido de Silício/química , Estereoisomerismo
4.
Plant Physiol ; 179(3): 1111-1131, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30659066

RESUMO

The transport and targeting of glutelin and prolamine mRNAs to distinct subdomains of the cortical endoplasmic reticulum is a model for mRNA localization in plants. This process requires a number of RNA-binding proteins (RBPs) that recognize and bind to mRNA cis-localization (zipcode) elements to form messenger ribonucleoprotein complexes, which then transport the RNAs to their destination sites at the cortical endoplasmic reticulum. Here, we present evidence that the rice (Oryza sativa) RNA-binding protein, RBP-L, like its interacting RBP-P partner, specifically binds to glutelin and prolamine zipcode RNA sequences and is required for proper mRNA localization in rice endosperm cells. A transfer DNA insertion in the 3' untranslated region resulted in reduced expression of the RBP-L gene to 10% to 25% of that in the wild-type. Reduced amounts of RBP-L caused partial mislocalization of glutelin and prolamine RNAs and conferred other general growth defects, including dwarfism, late flowering, and smaller seeds. Transcriptome analysis showed that RBP-L knockdown greatly affected the expression of prolamine family genes and several classes of transcription factors. Collectively, these results indicate that RBP-L, like RBP-P, is a key RBP involved in mRNA localization in rice endosperm cells. Moreover, distinct from RBP-P, RBP-L exhibits additional regulatory roles in development, either directly through its binding to corresponding RNAs or indirectly through its effect on transcription factors.


Assuntos
Retículo Endoplasmático/metabolismo , Oryza/metabolismo , Proteínas de Plantas/fisiologia , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/fisiologia , Transporte Biológico , Glutens/análise , Glutens/metabolismo , Oryza/genética , Fenilpropanolamina/análise , Fenilpropanolamina/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , RNA Mensageiro/análise , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Alinhamento de Sequência , Análise de Sequência de Proteína
5.
Drug Test Anal ; 10(2): 350-356, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28444836

RESUMO

Consumption of Ephedra alkaloids is prohibited in-competition by the World Anti-Doping Agency (WADA). In Taiwan, colds are often treated with Chinese herbal formulae containing Herba Ephedrae. We screened products sold in Taiwan and preliminarily assessed their relationships with WADA threshold violations. Fifty-six concentrated powder products, including 19 Chinese herbal formulae that contained Herba Ephedrae, were collected. The content of Ephedra alkaloids, namely ephedrine (E), methylephedrine (ME), norpseudoephedrine (NPE; cathine), pseudoephedrine (PE), and norephedrine (NE; phenylpropanolamine), was determined using a validated high-performance liquid chromatography method. The results revealed that the phenotypic indicators of the collected products, E/PE and E/total ratios, were 1.52-4.70 and 0.49-0.72, respectively, indicating that the Herba Ephedrae species in these products was probably E. sinica or E. equisetina, but not E. intermedia. The contents of E, ME, NPE, PE, and NE and the total alkaloid contents in the daily doses of the products were 0.45-34.97, 0.05-4.87, 0.04-3.61, 0.15-12.09, and 0.01-2.00 mg and 0.68-53.64 mg, respectively. The alkaloid contents followed a relatively consistent order (E > PE > ME ≈ NPE > NE), even for products from different manufacturers. We calculated that single doses of 50.0% and 3.6% of the products would result in the WADA thresholds of E and NPE being exceeded, respectively. Our data provide critical information for athletes and medical personnel, who should be wary of using complex Chinese herbal formulae in addition to over-the-counter products.


Assuntos
Alcaloides/análise , Medicamentos de Ervas Chinesas/análise , Ephedra/química , Efedrina/análogos & derivados , Fenilpropanolamina/análise , Pseudoefedrina/análise , Alcaloides/química , Cromatografia Líquida de Alta Pressão , Dopagem Esportivo , Ephedra/metabolismo , Ephedra/toxicidade , Efedrina/análise , Efedrina/química , Fenilpropanolamina/química , Pseudoefedrina/química , Taiwan
6.
Phytochem Anal ; 28(4): 257-266, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28124803

RESUMO

INTRODUCTION: Catha edulis (qat, khat, mirra) is a woody plant species that is grown and consumed in East Africa and Yemen for its stimulant alkaloids cathinone, cathine and norephedrine. Two Celastraceae species, in addition to qat, have been noted for their stimulant properties in ethnobotanical literature. Recent phylogenetic reconstructions place four genera in a clade sister to Catha edulis, and these genera are primary candidates to search for cathine and related alkaloids. OBJECTIVE: Determine if cathine or related alkaloids are present in species of Celastraceae other than Catha edulis. METHODS: Leaf samples from 43 Celastraceae species were extracted in water followed by basification of the aqueous extract and partitioning with methyl-t-butyl ether to provide an alkaloid-enriched fraction. The extract was derivatised in a two-stage process and analysed using GC-MS for the presence of cathine. Related alkaloids and other metabolites in this alkaloid-enriched fraction were tentatively identified. RESULTS: Cathinone, cathine and norephedrine were not detected in any of the 43 Celastraceae species assayed other than Catha edulis. However, the phenylalanine- or tyrosine-derived alkaloid phenylethylamine was identified in five species. Nine species were found to be enriched for numerous sterol- and terpene-like compounds. CONCLUSION: These results indicate that cathine is unique to Catha edulis, and not the compound responsible for the stimulant properties reported in related Celastraceae species. Copyright © 2017 John Wiley & Sons, Ltd.


Assuntos
Alcaloides/análise , Celastraceae/química , Cromatografia Gasosa-Espectrometria de Massas , Fenilpropanolamina/análise , Extratos Vegetais/análise , Celastraceae/classificação , Filogenia
7.
J Chromatogr Sci ; 54(8): 1271-6, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27165573

RESUMO

The stimulating herbal drug khat (cathine, cathinone) and its analog methcathinone are common substances of abuse in most countries. A GC-MS method was developed and validated for the detection and quantification of cathine, cathinone, methcathinone and ephedrine in oral fluid specimens. The analytes and internal standard (amphetamine-d5) were extracted from 0.5 mL oral fluids by ethyl acetate, and then the dried extracts were derivatized with heptafluorobutyric anhydride at 70°C for 30 min. The MS was used in selected ion monitoring mode. Ions monitored were m/z 117, 240 and 330 for cathine, m/z 77, 105 and 240 for cathinone, m/z 105, 210 and 254 for methcathinone, m/z 210, 254 and 344 for ephedrine and m/z 244 and 336 for amphetamine-d5 The calibration curves were linear (r(2)> 0.98) in the concentration range 20-2,000 ng/mL for all analytes. The intra- and inter-assay imprecisions were within (1.6-12.5%) and (1.5-9.5%), respectively, for all analytes. Intra-assay accuracies were between -5.9 and 6.7% for all analytes. The method was successfully applied to detect and quantify the target analytes from oral fluid specimens collected from Khat and methcathinone users.


Assuntos
Estimulantes do Sistema Nervoso Central/análise , Química Clínica/métodos , Cromatografia Gasosa-Espectrometria de Massas , Drogas Ilícitas/análise , Saliva/química , Alcaloides/análise , Efedrina/análise , Humanos , Fenilpropanolamina/análise , Propiofenonas/análise , Reprodutibilidade dos Testes
8.
J Chromatogr A ; 1440: 172-178, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26928873

RESUMO

A literature criticism is given on methods using currently gas chromatography mass spectrometry (GC/MS) to determine cathine (CAT), cathinone (CTN) and norephedrine (NE), jointly khatamines. In this study, khatamines' oximation, trimethylsilylation and mass fragmentation properties-applying N-Methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA), its trimethyliodosilane (TMIS) catalyst containing version (MSTFA(TMIS)), N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) and hexamethyldisilazane (HMDS)-was highlighted, at first. Derivatization, mass fragmentation and quantitation related, optimized model investigations have been carried out as a function of the reaction times and conditions. Special emphasis was put (i) on the stability of the primarily formed (CAT-2TMS, NE-2TMS, CTN-TMS(TMS-oximes)1,2), then transformed, fully derived (CAT-3TMS, NE-3MTS, CTN-2TMS(TMS-oximes)1,2) species, and, (ii) on the proportionally formed stable products, suitable to selective quantitation of all three natural amines, simultaneously. Results, as novelty to the field confirmed that (i) TMIS catalyzed trimethylsilyation triggers to form fully derivatized species unfortunately, in part only; while, (ii) khatamines' simultaneous quantitation needs to be carried out in a two steps derivatization process consisting of oximation (1st step, hydroxylamine in pyridine) and trimethylsilylation (2nd step, MSTFA), to the CAT-2TMS, NE-2TMS, CTN-TMS(TMS-oximes)1,2. These species were characterized with their retention, mass fragmentation and analytical performance properties, in model solutions and in the presence of plant tissues, as well: R(2), limit of quantitation (LOQ) data, expressed in pg/1µL injection basis, proved to be 62.5pg (CAT), 20pg (NE) and 62.5pg (CTN), respectively. The practical utility of proposal was enormously enhanced by the novel, direct sample preparation method. In this process, the freshly harvested, freeze-dried, then pulverized leaves of Catha edulis FORKS were directly derivatized, in the presence of the matrix. Reproducibility (in average 2.07 RSD% varying between 0.15 and 5.5 RSD%), linearity (0.9990-0.9994) and recovery (95.7-99.1%) values of the new sample preparation protocol was confirmed by the standard addition method for CAT, NE and CTN equally. From plant leaf, 0.061w/w% CAT and 0.014w/w% NE contents were obtained. In this tissue CTN was not found. Very likely attributable to the unfavorable climate for the plant: grown in Hungary of temperate zone and naturalized in the tropical Africa.


Assuntos
Alcaloides/análise , Técnicas de Química Analítica/métodos , Cromatografia Gasosa-Espectrometria de Massas , Fenilpropanolamina/análise , Acetamidas/química , África , Alcaloides/química , Catha/química , Fluoracetatos/química , Compostos de Organossilício/química , Fenilpropanolamina/química , Reprodutibilidade dos Testes , Compostos de Trimetilsilil/química
9.
Int J Sport Nutr Exerc Metab ; 26(5): 413-420, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26841433

RESUMO

Many studies have found that some dietary supplement product labels do not accurately reflect the actual ingredients. However, studies have not been performed to determine if ingredients in the same dietary supplement product vary over time. The objective of this study was to assess the consistency of stimulant ingredients in popular sports supplements sold in the United States over a 9-month period. Three samples of nine popular sports supplements were purchased over the 9-month period. The 27 samples were analyzed for caffeine and several other stimulants (including adulterants). The identity and quantity of stimulants were compared with stimulants listed on the label and stimulants found at earlier time points to determine the variability in individual products over the 9-month period. The primary outcome measure was the variability of stimulant amounts in the products examined. Many supplements did not contain the same number and quantity of stimulants at all time points over the 9-month period. Caffeine content varied widely in five of the six caffeinated supplements compared with the initial measurement (-7% to +266%). In addition, the stimulants-synephrine, octopamine, cathine, ephedrine, pseudoephedrine, strychnine, and methylephedrine-occurred in variable amounts in eight of the nine products. The significance of these findings is uncertain: the sample size was insufficient to support statistical analysis. In our sample of nine popular sports supplements, the presence and quantity of stimulants varied over a 9-month period. However, future studies are warranted to determine if the variability found is significant and generalizable to other supplements.


Assuntos
Estimulantes do Sistema Nervoso Central/análise , Suplementos Nutricionais , Rotulagem de Alimentos , Esportes , Cafeína/análise , Relação Dose-Resposta a Droga , Efedrina/análogos & derivados , Efedrina/análise , Humanos , Octopamina/análise , Fenilpropanolamina/análise , Projetos Piloto , Pseudoefedrina/análise , Estricnina/análise , Sinefrina/análise , Fatores de Tempo , Estados Unidos
10.
Electrophoresis ; 36(2): 305-11, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25262990

RESUMO

Introducing a new class of chiral selectors is an interesting work and this issue is still one of the hot topics in separation science and chirality. In this study, for the first time, sulfated maltodextrin (MD) was synthesized as a new anionic chiral selector and then it was successfully applied for the enantioseparation of five basic drugs (amlodipine, hydroxyzine, fluoxetine, tolterodine, and tramadol) as model chiral compounds using CE. This chiral selector has two recognition sites: a helical structure and a sulfated group which contribute to three corresponding driving forces; inclusion complexation, electrostatic interaction, and hydrogen binding. Under the optimized condition (buffer solution: 50 mM phosphate (pH 3.0) and 2% w/v sulfated MD; applied voltage: 18 kV; temperature: 20°C), baseline enantioseparation was observed for all mentioned chiral drugs. When instead of sulfated MD neutral MD was used under the same condition, no enantioseparation was observed which means the resolution power of sulfated MD is higher than neutral MD due to the electrostatic interaction between sulfated groups and protonated chiral drugs. Also, the countercurrent mobility of negatively charged MD (sulfated MD) allows more interactions between the chiral selector and chiral drugs and this in turn results in a successful resolution for the enantiomers. Furthermore, a higher concentration of neutral MD (approximately five times) is necessary to achieve the equivalent resolution compared with the negatively charged MD.


Assuntos
Eletroforese Capilar/métodos , Preparações Farmacêuticas/análise , Preparações Farmacêuticas/química , Polissacarídeos/química , Anlodipino/análise , Ânions , Compostos Benzidrílicos/análise , Soluções Tampão , Cresóis/análise , Eletroforese Capilar/instrumentação , Fluoxetina/análise , Concentração de Íons de Hidrogênio , Hidroxizina/análise , Fenilpropanolamina/análise , Fosfatos , Espectroscopia de Infravermelho com Transformada de Fourier , Estereoisomerismo , Sulfatos/química , Temperatura , Tartarato de Tolterodina , Tramadol/análise
11.
J Pharm Biomed Anal ; 90: 215-21, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24384498

RESUMO

During the stability study of Tolterodine tartrate drug product, two unknown impurities (Impurities I and II) were detected by ultra performance liquid chromatography (UPLC). Both impurities were isolated by preparative liquid chromatography and were subjected to mass and NMR spectral studies. Based on the spectral data, the Impurities I and II were characterized as N-(3-(2-hydroxy-5-methylphenyl)-3-phenylpropyl)-N,N-diisopropyl hydroxyl ammonium trifluoro acetate and 3-(2-hydroxy-5-methylphenyl)-N-isopropyl-3-phenylpropane-1-amine oxide respectively.


Assuntos
Compostos Benzidrílicos/química , Cromatografia Líquida de Alta Pressão/métodos , Cresóis/química , Contaminação de Medicamentos , Antagonistas Muscarínicos/química , Fenilpropanolamina/química , Compostos Benzidrílicos/análise , Cresóis/análise , Estabilidade de Medicamentos , Espectroscopia de Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/normas , Espectrometria de Massas/métodos , Antagonistas Muscarínicos/análise , Antagonistas Muscarínicos/normas , Fenilpropanolamina/análise , Tartarato de Tolterodina
12.
J Forensic Leg Med ; 20(6): 667-72, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23910858

RESUMO

In recent years, synthetic cannabinoids have been frequently observed in seized materials all over the world. This new generation of designer drugs, mixed with herbal substances, is also known as "Herbal Highs" or "Legal Highs". There are many articles about the history, type and pharmaco-chemical properties of synthetic cannabinoids in the literature; however the number of articles about the frequency of their detection is limited. In this study, we evaluated the type and detection frequency of synthetic cannabinoids in Istanbul and its surrounding area. The reports of the Council of Forensic Medicine-Istanbul Narcotic Department were retrospectively reviewed for the presence of synthetic cannabinoids in herbal compounds sent by the judicial authorities between August 01, 2010 and March 31, 2012. Among 1200 herbal compounds, 1179 of them (98.3%) contained synthetic cannabinoids. Twenty-one samples (1.7%) had other psychoactive substances. The analysis of 1179 samples showed that JWH-018 was present in 1172 (99.4%) of the samples. JWH-081 was found in 777 samples (65.9%) together with JWH-018. Samples had different package names. "Bonzai Aromatic Potpourri" (n = 755; 64.0%) and "Bonzai Plant Growth Regulator" (n = 316; 26.8%) were the most common product names amongst the herbal products in this study. It is clear from the present study and previous studies that brand name of synthetic cannabinoids that dominate the market exhibit regional differences as to the type and detection frequency of synthetic cannabinoids and the content of herbal highs packages. The number and diversity of synthetic cannabinoid compounds have increased dramatically in the drug market in recent years. New, different, potent derivatives appear on the market almost every day and this presents important problems that need to be solved by scientists and judicial authorities working to prevent their harm. These problems include the limited knowledge about their frequency, the lack of analytical data and reference standards for analysis of these new derivates, the lack of information on their toxic effects, and information about the metabolism and metabolites for toxicological analysis in human subjects.


Assuntos
Canabinoides/análise , Drogas Desenhadas/química , Preparações de Plantas/química , Alcaloides/análise , Toxicologia Forense , Humanos , Indóis , Metanfetamina/análogos & derivados , Metanfetamina/análise , Naftalenos , Fenilpropanolamina/análise , Psicotrópicos/análise , Estudos Retrospectivos , Turquia
13.
Artigo em Inglês | MEDLINE | ID: mdl-23685239

RESUMO

The GC method previously reported by our research group for the analysis of the active principles of Catha edulis, i.e. cathine, cathinone and phenylpropanolamine, was considerably improved. N-methyl-N-trimethylsilyl-trifluoroacetamide (MSTFA) as derivatizing agent was employed, thus allowing an accurate determination of the analytes and a suitable internal standard for quantitative analyses (nicotinamide) was introduced. Moreover the chromatographic conditions were carefully studied to improve the separation of the alkaloids and sensitivity. To this end different chromatographic capillary columns and temperature gradients were investigated. The optimized GC method was validated and resulted adequate for the application in forensic analysis. Finally on behalf of the Tribunal, C. edulis vegetable material seized by the police in northern Italy was analyzed, the quantity of cathine ranging from 0.095 to 0.29%, the quantity of PPA from 0.010 to 0.21% and the quantity of cathinone from 0.025 to 0.374% of the weight of the vegetable material.


Assuntos
Catha/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Alcaloides/análise , Itália , Fenilpropanolamina/análise
14.
Forensic Sci Int ; 228(1-3): 154-9, 2013 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-23597752

RESUMO

A capillary electrophoretic method, which allowed the detection and separation of the active principles of Catha edulis, i.e. cathinone, cathine and phenylpropanolamine, was developed. A suitable internal standard (nicotinamide), which permitted the quantification of the analytes reducing the variability of the migration times due to EOF changes, was identified. The analytical method was validated, assessing linearity, sensitivity and repeatability, showing optimal features for the analysis of the vegetable material. Moreover extraction conditions were investigated to achieve the exhaustion of the plant material in the fastest and most efficient way to meet the requirements of the Court.


Assuntos
Catha/química , Eletroforese Capilar , Extratos Vegetais/química , Alcaloides/análise , Alcaloides/química , Estrutura Molecular , Fenilpropanolamina/análise , Fenilpropanolamina/química , Reprodutibilidade dos Testes
15.
Plant Foods Hum Nutr ; 68(1): 47-51, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23329422

RESUMO

Seeds of Mucuna pruriens (L.) DC. (Fabaceae) were analyzed for protein composition of protein bodies isolated from cotyledons. Protein bodies were successfully separated by Lympholyte and those of dry seeds, observed by scanning electron microscope, were elliptical or spherical in shape with a diameter of 5-12 µm. Protein content in dry seed protein bodies was 10.6 mg/g dry weight. Globulin was the largest protein fraction isolated (62.5 %), followed by albumin (18.3 %), glutelin (15.8 %) and prolamin (3.4 %). The prolamin fraction and high glutelin content are uncommon in legumes. SDS-PAGE of albumins, globulins, prolamins and glutelins provided different band numbers and molecular weights under reducing and non reducing conditions and suggested that the albumin fraction is rich in disulphide bonds.


Assuntos
Albuminas/análise , Cotilédone/química , Globulinas/análise , Glutens/análise , Mucuna/química , Fenilpropanolamina/análise , Proteínas de Armazenamento de Sementes/análise , Albuminas/metabolismo , Cotilédone/metabolismo , Proteínas Alimentares/análise , Globulinas/metabolismo , Glutens/metabolismo , Microscopia Eletrônica de Varredura , Peso Molecular , Mucuna/metabolismo , Fenilpropanolamina/metabolismo , Proteínas de Armazenamento de Sementes/metabolismo
16.
Talanta ; 96: 153-60, 2012 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-22817943

RESUMO

Two new ion-selective electrodes of the plastic membrane type for the determination of Tolterodine (Tol) were prepared. These electrodes depend on the incorporation of the ion-exchangers of the above mentioned drug with phosphotungestic acid (PTA) or Silicotungestic acid (STA) in a PVC matrix. A comparative study is made between the performance characteristics of electrodes containing ion-exchanger in batch and FIA conditions. The usable concentration range of the electrodes was found to be (1.0×10(-5)-1.0×10(-2) and 5.0×10(-5)-1.0×10(-2)M) in batch and FIA conditions, respectively. The electrodes have nearly the same usable concentration, pH range and exhibited high selectivity toward Tol in the presence of many inorganic cations and can be used in biological fluids such as urine and plasma. The dissolution profile of the investigated drug as well as its assay in pure and pharmaceutical preparations was performed, and the results were relatively accurate and precise as indicated by the recovery values and coefficients of variation.


Assuntos
Compostos Benzidrílicos/análise , Cresóis/análise , Análise de Injeção de Fluxo/métodos , Fenilpropanolamina/análise , Potenciometria/métodos , Eletrodos , Concentração de Íons de Hidrogênio , Tartarato de Tolterodina
17.
Am J Clin Nutr ; 95(3): 670-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22258271

RESUMO

BACKGROUND: Certain immunotoxic peptides from gluten are resistant to gastrointestinal digestion and can interact with celiac-patient factors to trigger an immunologic response. A gluten-free diet (GFD) is the only effective treatment for celiac disease (CD), and its compliance should be monitored to avoid cumulative damage. However, practical methods to monitor diet compliance and to detect the origin of an outbreak of celiac clinical symptoms are not available. OBJECTIVE: We assessed the capacity to determine the gluten ingestion and monitor GFD compliance in celiac patients by the detection of gluten and gliadin 33-mer equivalent peptidic epitopes (33EPs) in human feces. DESIGN: Fecal samples were obtained from healthy subjects, celiac patients, and subjects with other intestinal pathologies with different diet conditions. Gluten and 33EPs were analyzed by using immunochromatography and competitive ELISA with a highly sensitive antigliadin 33-mer monoclonal antibody. RESULTS: The resistance of a significant part of 33EPs to gastrointestinal digestion was shown in vitro and in vivo. We were able to detect gluten peptides in feces of healthy individuals after consumption of a normal gluten-containing diet, after consumption of a GFD combined with controlled ingestion of a fixed amount of gluten, and after ingestion of <100 mg gluten/d. These methods also allowed us to detect GFD infringement in CD patients. CONCLUSIONS: Gluten-derived peptides could be sensitively detected in human feces in positive correlation with the amount of gluten intake. These techniques may serve to show GFD compliance or infringement and be used in clinical research in strategies to eliminate gluten immunotoxic peptides during digestion. This trial was registered at clinicaltrials.gov as NCT01478867.


Assuntos
Doença Celíaca/dietoterapia , Dieta Livre de Glúten , Epitopos/análise , Fezes/química , Gliadina/análise , Cooperação do Paciente , Adolescente , Adulto , Criança , Pré-Escolar , Cromatografia de Afinidade/métodos , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Entrevistas como Assunto , Masculino , Fenilpropanolamina/análise , Adulto Jovem
18.
J Ethnopharmacol ; 140(1): 193-6, 2012 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-22244798

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Khat chewing amongst the UK communities originating from Yemen and the East African coast is suggested to create dependency through its main stimulant components (cathinone, norephedrine and norpseudoephedrine) on the central nervous system. AIMS OF THE STUDY: To validate self-reported khat chewing behaviours by measuring levels of cathinone, norephedrine and norpseudoephedrine in saliva and to explore their associations with self-reported khat chewing dependency. MATERIALS AND METHODS: Face-to-face interviews were conducted amongst 30 male UK-resident khat chewers. Saliva samples were collected from each participant and high-performance liquid chromatography (HPLC) employed to extract and quantify the levels of the biomarkers. RESULTS: The mean (SD) for cathinone and the composite norephedrine and norpseudoephedrine levels were 33.93 (±39.20) and 29.28 (±26.32)µg/mL respectively. These biomarkers were significantly associated (p≤0.05) with khat chewing dependency. CONCLUSIONS: Validation of self-reported khat chewing is possible. Khat chewing dependency correlates significantly with biomarker levels in saliva. Replication is required.


Assuntos
Catha/química , Estimulantes do Sistema Nervoso Central/análise , Comportamento Perigoso , Entrevistas como Assunto/normas , Mastigação , Saliva/química , Autorrelato/normas , Adulto , África/etnologia , Alcaloides/efeitos adversos , Alcaloides/análise , Biomarcadores/análise , Catha/efeitos adversos , Estimulantes do Sistema Nervoso Central/efeitos adversos , Cromatografia Líquida de Alta Pressão , Revelação , Humanos , Masculino , Pessoa de Meia-Idade , Fenilpropanolamina/efeitos adversos , Fenilpropanolamina/análise , Preparações de Plantas/efeitos adversos , Preparações de Plantas/química , Reprodutibilidade dos Testes , Transtornos Relacionados ao Uso de Substâncias , Reino Unido , Iêmen/etnologia
19.
Forensic Sci Int ; 217(1-3): 87-92, 2012 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-22024653

RESUMO

In the last years, all the vegetable material supposed to belong to the Catha Edulis species, seized at the Malpensa and Orio al Serio airports, were analyzed in our laboratory on behalf of the Tribunals of Busto Arsizio and Bergamo, respectively. After a preliminary botanic examination, the quali-quantitative determination of the active principles cathinone, cathine and phenylpropanolamine (PPA) was carried out by means of GC/MS and GC/FID techniques, which meet the requirements of the forensic analyses. We developed a fast, effective and reliable derivatization procedure which allowed to simultaneously detect cathine and PPA, whose discrimination is mandatory since PPA is not a psychoactive agent. Cathine was distributed in the various parts of the plant (leaves and stems) and its quantity ranged from 0.03% to 0.17% of the weight of the vegetable material; PPA was not detected in the twigs and its quantity in the leaves ranged from 0.07% to 0.16%. The quantitative determination of cathinone was carried out directly on the methanol solution after maceration of the vegetable material, its quantity ranging from 0.02% to 0.10%. No significant difference in the content of the two active principles was found between the fresh and the dried material.


Assuntos
Alcaloides/análise , Catha/química , Fenilpropanolamina/análise , Estimulantes do Sistema Nervoso Central/análise , Dessecação , Ionização de Chama , Toxicologia Forense , Cromatografia Gasosa-Espectrometria de Massas , Folhas de Planta/química , Caules de Planta/química
20.
J Chromatogr A ; 1218(42): 7655-62, 2011 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-21899853

RESUMO

A method for simultaneous determination of eight adulterants including two appetite suppressants, two energy expenditure-enhancing drugs, one diuretic and three cathartics in slimming functional foods by high performance liquid chromatography with electrospray ionization-tandem mass spectrometry (HPLC-ESI-MS/MS) was established. After samples were ultrasonically extracted with 70% (v/v) methanol aqueous solution and centrifuged, the components of ephedrine, norpseudoephedrine, fenfluramine, sibutramine, clopamide, emodin, rhein, and chrysophanol in sample solution were separated by a Hypersil Gold column (2.1 mm × 150 mm, 5 µm) using a programmed gradient elution. A mobile phase consisting of 0.02% (v/v) formic acid-ammonium formate buffer solution (pH=3.50) and methanol was used for elution with a flow rate set at 250 µL/min and column temperature of 25 °C. Qualitative determination was based on characteristic ion pairs and retention time of the targeted compounds using SRM (selective reaction monitoring) mode. Clenbuterol and ibuprofen were internal standards in positive and negative ionization mode, respectively. The internal standard curves were used for quantification measurement. The average recoveries of three different concentrations were from 80.2% to 94.5%. The limits of detection (LODs) were from 0.03 to 0.66 mg/kg (except chrysophanol 1.6 mg/kg). The linear dynamic range covered from 1 to 500 µg/L (except chrysophanol 50-5000 µg/L) for the twelve samples analyzed. Adulterants in four different kinds of slimming functional foods were determined by this developed method, and satisfactory results were obtained. These experimental results showed that, adulteration of sibutramine or/and fenfluramine were the major adulterating components with contents varying from 6.1 to 1.3×10(3) mg/kg and 1.9 to 9.7×10(3) mg/kg, respectively. In addition, three cathartic compounds were detected in six of those tested samples, and ephedrine, norpseudoephedrine and clopamide were not detected in all samples.


Assuntos
Cromatografia Líquida/métodos , Dieta Redutora , Contaminação de Alimentos/análise , Alimento Funcional/análise , Espectrometria de Massas em Tandem/métodos , Antraquinonas/análise , Clopamida/análise , Ciclobutanos/análise , Emodina/análise , Efedrina/análise , Fenfluramina/análise , Alimento Funcional/normas , Modelos Lineares , Metanol , Fenilpropanolamina/análise , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Temperatura
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