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1.
J Pharm Biomed Anal ; 218: 114871, 2022 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-35671680

RESUMEN

Alkaloids play an important role in the chemical composition of tobacco, due to their effects that have led to the global consumption of this commodity. The ß-carboline alkaloids present inhibitory action against the enzyme monoamine oxidase (MAO), which enhances the susceptibility to chemical dependence in smokers. There is a need for scientific studies to ensure the correct identification and quantification of these compounds in tobacco matrices. In this work, we present the development and validation of a microextraction analytical method for determination and quantification of the alkaloids harmaline, harmalol, harmane, harmine, norharmane, and tetrahydroharmine in natural and processed samples of tobacco, employing micro-matrix solid-phase dispersion (µMSPD), ultra-performance liquid chromatography (UPLC), and mass spectrometry (MS). The optimized µMSPD procedure employed of 0.01 g of sample, 0.1 g of Discovery® DPA-6S adsorbent, and elution with 2 mL of aqueous 1 % formic acid solution, resulting in a fast, practical, economical, and environmentally friendly technique. Validation of the methodology showed that it presented good linearity (R2 > 0.9945), satisfactory accuracy and precision (in the range from 72 ± 16 % to 109 ± 9 %), and limits of quantification (LOQ) and detection (LOD) in the ranges 0.02-1.0 µg g-1 and 0.01-0.2 µg g-1, respectively. The developed method was applied to tobacco samples, proving to be efficient for determination of ß-carboline alkaloids. The compounds harmane and norharmane were quantified in samples of fresh tobacco leaves, cured tobacco leaves, twisted tobacco, and cigarettes. Harmine was only not quantified in the cigarettes.


Asunto(s)
Alcaloides , Productos de Tabaco , Alcaloides/análisis , Carbolinas/química , Cromatografía Líquida de Alta Presión/métodos , Cromatografía Liquida , Harmina/análisis , Harmina/química , Espectrometría de Masas , Nicotiana , Productos de Tabaco/análisis
2.
J AOAC Int ; 100(3): 820-824, 2017 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-28105971

RESUMEN

Ayahuasca is a potent hallucinogenic beverage prepared from Banisteriopsis caapi in combination with other psychoactive plants. N,N-dimethyltryptamine, tryptamine, harmine, harmaline, harmalol, and tetrahydroharmine were quantified in ayahuasca samples using a simple and low-cost method based on SPE and LC with UV diode-array detection. The experimental variables that affect the SPE method, such as type of solid phase and nature of solvent, were optimized. The method showed good linearity (r > 0.9902) and repeatability (RSD < 0.8%) for alkaloid compounds, with an LOD of 0.12 mg/L. The proposed method was used to analyze 20 samples from an ayahuasca cooking process from a religious group located in the municipality of Fortaleza, state of Ceará, Brazil. The results showed that concentrations of the target compounds ranged from 0.3 to 36.7 g/L for these samples.


Asunto(s)
Banisteriopsis/química , Bebidas/análisis , Carbolinas/análisis , Alucinógenos/análisis , Triptaminas/análisis , Brasil
3.
Talanta ; 106: 394-8, 2013 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-23598143

RESUMEN

A novel analytical approach combining solid-phase microextraction (SPME)/gas chromatography ion trap mass spectrometry (GC-IT-MS) was developed for the detection and quantification N,N-dimethyltryptamine (DMT), a powerful psychoactive indole alkaloid present in a variety of South American indigenous beverages, such as ayahuasca and vinho da jurema. These particular plant products, often used within a religious context, are increasingly consumed throughout the world following an expansion of religious groups and the availability of plant material over the Internet and high street shops. The method described in the present study included the use of SPME in headspace mode combined GC-IT-MS and included the optimization of the SPME procedure using multivariate techniques. The method was performed with a polydimethylsiloxane/divinylbenzene (PDMS/DVB) fiber in headspace mode (70 min at 60 °C) which resulted in good precision (RSD<8.6%) and accuracy values (71-109%). Detection and quantification limits obtained for DMT were 0.78 and 9.5 mg L(-1), respectively and good linearity (1.56-300 mg L(-1), r(2)=0.9975) was also observed. In addition, the proposed method showed good robustness and allowed for the minimization of sample manipulation. Five jurema beverage samples were prepared in the laboratory in order to study the impact of temperature, pH and ethanol on the ability to extract DMT into solution. The developed method was then applied to the analysis of twelve real ayahuasca and vinho da jurema samples, obtained from Brazilian religious groups, which revealed DMT concentration levels between 0.10 and 1.81 g L(-1).


Asunto(s)
Banisteriopsis/química , Bebidas/análisis , Alucinógenos/análisis , N,N-Dimetiltriptamina/análisis , Extractos Vegetales/química , Psychotria/química , Conducta Ceremonial , Dimetilpolisiloxanos , Cromatografía de Gases y Espectrometría de Masas , Humanos , Concentración de Iones de Hidrógeno , Límite de Detección , Microextracción en Fase Sólida , Temperatura , Compuestos de Vinilo
4.
Drug Test Anal ; 4(7-8): 636-48, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22577086

RESUMEN

The consumption of ayahuasca, a hallucinogenic beverage used by indigenous communities in the Amazon, is increasing worldwide due to the expansion of syncretic religions founded in the north of Brazil in the first half of the twentieth century, such as Santo Daime and União do Vegetal. Another example is the jurema wine, a drink that originated from indigenous cultures of the northeast of Brazil. It is currently used for several religious practices throughout Brazil involving urban neo-shamanic rituals and syncretic Brazilian religions, such as Catimbó and Umbanda. Both plant products contain N,N-dimethyltryptamine which requires co-administration of naturally occurring monoamine oxidase inhibitors, for example ß-carboline derivatives, in order to induce its psychoactive effects in humans. This review explores the cultural use of tryptamines and ß-carbolines and focuses on the analytical techniques that have been recently applied to the determination of these compounds in ayahuasca, its analogues, and the plants used during the preparation of these beverages.


Asunto(s)
Bebidas/análisis , Carbolinas/análisis , Alucinógenos/análisis , Extractos Vegetales/análisis , Plantas/química , Triptaminas/análisis , Banisteriopsis/química , Brasil , Conducta Ceremonial , Técnicas de Química Analítica/métodos , Humanos , Religión
5.
J Chromatogr B Analyt Technol Biomed Life Sci ; 881-882: 107-10, 2012 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-22209595

RESUMEN

N,N-dimethyltryptamine (DMT) is a potent hallucinogen found in beverages consumed in religion rituals and neo-shamanic practices over the world. Two of these religions, Santo Daime and União do Vegetal (UDV), are represented in countries including Australia, the United States and several European nations. In some of this countries there have been legal disputes concerning the legalization of ayahuasca consumption during religious rituals, a beverage rich in DMT. In Brazil, even children and pregnant women are legally authorized to consume ayahuasca in a religious context. A simple and low-cost method based on matrix solid-phase dispersion (MSPD) and gas chromatography with mass spectrometric detection (GC-MS) has been optimized for the determination of N,N-dimethyltryptamine in Mimosa tenuiflora inner bark. The experimental variables that affect the MSPD method, such as the amounts of solid-phase and herbal sample, solvent nature, eluate volume and NaOH concentration were optimized using an experimental design. The method showed good linearity (r = 0.9962) and repeatability (RSD < 7.4%) for DMT compound, with detection limit of 0.12 mg/g. The proposed method was used to analyze 24 samples obtained locally. The results showed that concentrations of the target compound in M. tenuiflora barks, ranged from 1.26 to 9.35 mg/g for these samples.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas/métodos , Mimosa/química , N,N-Dimetiltriptamina/análisis , Extracción en Fase Sólida/métodos , Límite de Detección , Modelos Lineales , N,N-Dimetiltriptamina/aislamiento & purificación , Corteza de la Planta/química , Reproducibilidad de los Resultados
6.
J Chromatogr A ; 1203(1): 99-104, 2008 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-18657817

RESUMEN

A method based on solid-phase microextraction (SPME) and gas chromatography with flame ionization detection (GC-FID) has been optimized for the determination of benzene, toluene, ethylbenzene and xylenes (BTEX) in water released from a waste treatment plant. The extraction step was optimized using fractional factorial and central composite designs including the following experimental factors: saline concentration; extraction time; desorption time; agitation velocity; headspace volume. A multiple function was used to describe the experimental conditions for simultaneous extraction of the compounds. The procedure, based on direct SPME at 50 degrees C, using a polydimethylsiloxane fiber, showed good linearity (r>0.997 over a concentration range 2-200 microg L(-1)) and repeatability (relative standard deviation (RSD)<4.23%) for all compounds, with limits of detection ranging from 0.05 to 0.28 microg L(-1), and limits of quantification ranging from 0.14 to 0.84 microg L(-1). Concentrations of the target compounds in these samples were between 145.8 and 1891 microg L(-1).


Asunto(s)
Derivados del Benceno/análisis , Benceno/análisis , Cromatografía de Gases/métodos , Microextracción en Fase Sólida/métodos , Tolueno/análisis , Contaminantes Químicos del Agua/análisis , Xilenos/análisis , Análisis Multivariante , Reproducibilidad de los Resultados , Incertidumbre , Eliminación de Residuos Líquidos
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