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1.
Artículo en Inglés | MEDLINE | ID: mdl-35921604

RESUMEN

2- and 3-monochloropropanediol esters (MCPDEs) are most commonly formed as process-induced contaminants during the refinement of vegetable oils used for food production. 'In vivo' hydrolysis of 3-MCPDEs releases the potential carcinogen 3-monochloropropanediol (3-MCPD). Levels of MCPDEs in infant formula are of particular concern, as refined oils are commonly used as main fat ingredients. For this study, infant formula samples (powders, liquid concentrates and ready-to-feed infant formula samples) from the Canadian market were purchased and analysed in 2015 (35 samples) and 2019 (33 samples). MCPDE concentrations (expressed as free MCPD equivalents) were examined through an indirect analytical approach, applying acid-catalysed ester cleavage and using cyclohexanone as derivatising agent. Labelled diesters were used as internal standards. 2015 Survey data were analysed by gas chromatography-mass spectrometry (GC-MS) in selected ion monitoring mode (SIM). 2019 Survey data were analysed with an updated method using GC-MS/MS in multiple reaction monitoring modes (MRM). In 2015, levels in reconstituted formula ranging from 3.7 ng/g to 111 ng/g for 3-MCPD and 2.2 ng/g to 56.2 ng/g for 2-MCPD were found. In 2019, levels ranging from 3.9 ng/g to 74.8 ng/g for 3-MCPD and 1.0 ng/g to 33.9 ng/g for 2-MCPD were found. A significantly reduced mean of combined MCPDEs was observed between 2015 and 2019 data (64.5 ng/g, standard deviation (SD) 8.6 ng/g in 2015 to 31.8 ng/g, SD 5.6 ng/g in 2019, p-value = 0.024). For the majority of manufacturers, the data comparison among brand products over time shows decreased levels of MCPDEs. Occurrence data of MCPDEs, including data from previously published surveys (2012/2013), were also compared and a temporal trend was established.


Asunto(s)
alfa-Clorhidrina , Canadá , Carcinógenos/análisis , Ciclohexanonas/análisis , Ésteres/análisis , Contaminación de Alimentos/análisis , Glicerol/análisis , Humanos , Lactante , Fórmulas Infantiles/análisis , Aceites de Plantas/análisis , Glicoles de Propileno , Espectrometría de Masas en Tándem/métodos , alfa-Clorhidrina/análisis
2.
Artículo en Inglés | MEDLINE | ID: mdl-32787691

RESUMEN

In this study, we established a rapid and sensitive HPLC-MS/MS method for quantitative determination of tembotrione and its metabolite AE 1417268 (M5) in corn, corn oil, beef, pork, chicken, and eggs. Both analytes eluted from a C18 column within 6 min. The electrospray ionisation-positive mode was used for tembotrione, whereas the negative mode was used for M5. Acetonitrile was the extractant for all samples, and the addition of 2 g NaCl to each homogenised sample facilitated the extraction of the analytes into acetonitrile. The extracted analytes were further purified by the addition of 50 mg of C18 sorbent (25 mg GCB was also added to corn samples) for subsequent HPLC-MS/MS analysis. Satisfactory calibration-curve linearities (R2 ≥ 0.997) were obtained for the two analytes at concentrations of 1-500 µg/L. Mean recoveries in different matrices ranged from 73.7% to 110.4%, whereas intra-day and inter-day relative standard deviations were <15% for all concentrations of spiked analytes. The limit of quantification was 2 µg/kg for each analyte in all matrices. In food samples obtained from markets, residual tembotrione and M5 were all below the limits of quantification. These results confirm that the method is suitable for the routine monitoring of residual tembotrione and M5 in a variety of food matrices.


Asunto(s)
Aceite de Maíz/análisis , Ciclohexanonas/análisis , Contaminación de Alimentos/análisis , Sulfonas/análisis , Zea mays/química , Animales , Bovinos , Pollos , Cromatografía Líquida de Alta Presión , Ciclohexanonas/metabolismo , Huevos/análisis , Estructura Molecular , Sulfonas/metabolismo , Espectrometría de Masas en Tándem
3.
Food Chem ; 331: 127358, 2020 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-32593795

RESUMEN

Saffron, stigmas of Crocus sativus, is one of the most precious spices used as food colorant and flavoring agent. Due to its scarce source and high cost, it is liable to fraudulent admixture with allied plants "safflower and calendula". In this study, gas chromatography-mass spectrometry (GC-MS) was employed to determine authenticity, adulterants detection, and to assess the roasting impact on its aroma. A total of 93 volatiles were identified belonging to different classes viz. aldehydes, alcohols, ketones, aliphatic hydrocarbons, aromatics, mono-and sesquiterpenes, oxides/ethers and pyrans/furans. Principle component analysis (PCA) identified safranal and 2-caren-10-al as discriminatory volatile markers of saffron from its allied flowers, later found enriched in estragole, ß-caryophyllene and eugenol. PCA model also revealed markers for freshly dried versus long-stored saffron, with ketoisophorone as freshness marker versus safranal as an ageing indicator. Safranal was further identified as a marker to distinguish saffron from safflower, whereas calendula aroma was predominated by monoterpene hydrocarbons.


Asunto(s)
Crocus/química , Contaminación de Alimentos/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Especias/análisis , Compuestos Orgánicos Volátiles/análisis , Biomarcadores/análisis , Calendula/química , Carthamus tinctorius/química , Ciclohexanonas/análisis , Ciclohexenos , Flores/química , Análisis de los Alimentos/métodos , Almacenamiento de Alimentos , Industria de Procesamiento de Alimentos , Irán , Odorantes/análisis , España , Terpenos
4.
J Agric Food Chem ; 64(12): 2498-505, 2016 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-26551795

RESUMEN

Bamboo shoots are a delicacy in Asia. Two novel compounds, adenine-(1'R,2'R,3'R)-cyclic butanetetraol carbonate (16) and (-)-(7R,8S)-(4-hydroxy-3-methoxyphenylglycerol 9-O-ß-D-[6-O-4-hydroxy-3-methoxybenzoyl])-glucopyranoside (20), together with 12 known nucleosides (1-12), 3 amino acids (13-15), ß-carboline (17), and 2 megastigmane glycosides (18, 19) were isolated from bamboo shoots (Phyllostachys pubescens). Their structures and absolute configurations were rigorously determined by detailed spectroscopic analysis, and the composition of carbohydrates in bamboo shoots was qualitatively detected and quantitatively analyzed with ion chromatography. A simple, rapid, sensitive, and accurate HPLC-UV analysis was built for routine edible quality control of bamboo shoots, and 12 major components of bamboo shoots were quantitatively analyzed. The major chemical constituents of bamboo shoots were determined to be carbohydrates, amino acids, and nucleotides. These findings are correctives to the usual view of bamboo shoots chemical composition, and the previous research reports about the chemical composition of bamboo shoots may have taken the aromatic amino acids and nucleotides for flavonoids and phenolic acids.


Asunto(s)
Medicamentos Herbarios Chinos/química , Glicósidos/aislamiento & purificación , Poaceae/química , Aminoácidos/análisis , Carbohidratos/análisis , Carbolinas/análisis , Cromatografía Líquida de Alta Presión , Ciclohexanonas/análisis , Glucósidos/análisis , Glicósidos/química , Estructura Molecular , Norisoprenoides/análisis , Resonancia Magnética Nuclear Biomolecular , Nucleótidos/análisis , Estereoisomerismo
5.
J Med Toxicol ; 8(1): 15-32, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22271566

RESUMEN

Despite their widespread Internet availability and use, many of the new drugs of abuse remain unfamiliar to health care providers. The herbal marijuana alternatives, like K2 or Spice, are a group of herbal blends that contain a mixture of plant matter in addition to chemical grade synthetic cannabinoids. The synthetic cathinones, commonly called "bath salts," have resulted in nationwide emergency department visits for severe agitation, sympathomimetic toxicity, and death. Kratom, a plant product derived from Mitragyna speciosa Korth, has opioid-like effects, and has been used for the treatment of chronic pain and amelioration of opioid-withdrawal symptoms. Salvia divinorum is a hallucinogen with unique pharmacology that has therapeutic potential but has been banned in many states due to concerns regarding its psychiatric effects. Methoxetamine has recently become available via the Internet and is marked as "legal ketamine." Moreover, the piperazine derivatives, a class of amphetamine-like compounds that includes BZP and TMFPP, are making a resurgence as "legal Ecstasy." These psychoactives are available via the Internet, frequently legal, and often perceived as safe by the public. Unfortunately, these drugs often have adverse effects, which range from minimal to life-threatening. Health care providers must be familiar with these important new classes of drugs. This paper discusses the background, pharmacology, clinical effects, detection, and management of synthetic cannabinoid, synthetic cathinone, methoxetamine, and piperazine exposures.


Asunto(s)
Alcaloides/toxicidad , Cannabinoides/toxicidad , Ciclohexanonas/toxicidad , Ciclohexilaminas/toxicidad , Mitragyna/toxicidad , Piperazinas/toxicidad , Psicotrópicos/toxicidad , Salvia/toxicidad , Alcaloides/análisis , Alcaloides/farmacología , Alcaloides/uso terapéutico , Cannabinoides/análisis , Cannabinoides/farmacología , Cannabinoides/uso terapéutico , Ciclohexanonas/análisis , Ciclohexanonas/farmacología , Ciclohexanonas/uso terapéutico , Ciclohexilaminas/análisis , Ciclohexilaminas/farmacología , Ciclohexilaminas/uso terapéutico , Humanos , Piperazinas/análisis , Piperazinas/farmacología , Piperazinas/uso terapéutico , Psicotrópicos/análisis , Psicotrópicos/farmacología , Psicotrópicos/uso terapéutico
6.
Se Pu ; 29(10): 983-7, 2011 Oct.
Artículo en Chino | MEDLINE | ID: mdl-22268354

RESUMEN

A method of high performance liquid chromatography (HPLC) was developed for the separation and determination of six acidic components (cohumulone, humulone, adhumulone, colupulone, lupulone and adlupulone) in hops extracts. The effects of several important factors, such as the addition of acid, the organic solvent of elution solution and the column temperature, were investigated to acquire the optimum conditions. The separation was carried out on a Hypersil ODS2 column (250 mm x 4. 6 mm, 5 microm). A mixture of acetonitrile-0. 1% (v/v) phosphoric acid solution (pH 2. 2) (65: 35, v/v) was used as the mobile phase at a flow rate of 1. 0 mL/min in isocratic elution mode. The column temperature was kept at room temperature, and the detection wavelength was set at 315 nm. The six acidic components reached baseline separation, and were identified by ultraviolet spectroscopy, infrared spectroscopy and mass spectrometry. The results show that this method is suitable for the analysis of acidic components in hops extracts owing to the stable and simple performance.


Asunto(s)
Ácidos/análisis , Cromatografía Líquida de Alta Presión/métodos , Humulus/química , Extractos Vegetales/análisis , Ciclohexanonas/análisis , Ciclohexenos/análisis , Terpenos/análisis
7.
Immunopharmacol Immunotoxicol ; 32(4): 705-7, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20233126

RESUMEN

The leaf parts of Clerodendron trichotomum were extracted and the major essential oils composition and immunotoxicity effects were studied. The analyses were conducted by gas chromatography-mass spectroscopy (GC-MS) revealed that the essential oils of C. trichotomum (CTEO). The CTEO yield was 0.071%, and GC/MS analysis revealed that its major constituents were Hexanal (3.31%), 5-Me-3-heptanone (1.71%), 2,6,6-trime-cyclohexanone (2.23%), 2,6,10,15-tetrame-heptadecane (24.21%) and Linalool (31.2%). The essential oil had a significant toxic effect against early fourth-stage larvae of Aedes aegypti L with an LC(50) value of 32.78 ppm and an LC(90) value of 93.72 ppm. 2,6,10,15-tetrame-heptadecane was the most toxic among the two major components (2,6,10,15-tetrame-heptadecane and Linalool), with an LC(50) value near 43.9 ppm. The results could be useful in search for newer, safer, and more effective natural immunotoxicity agents against A. aegypti.


Asunto(s)
Aedes/efectos de los fármacos , Alcanos/farmacología , Clerodendrum/química , Aceites Volátiles/farmacología , Extractos Vegetales/farmacología , Terpenos/farmacología , Monoterpenos Acíclicos , Aldehídos/análisis , Alcanos/análisis , Animales , Ciclohexanonas/análisis , Cromatografía de Gases y Espectrometría de Masas , Cetonas/análisis , Larva/efectos de los fármacos , Dosificación Letal Mediana , Monoterpenos/análisis , Monoterpenos/farmacología , Aceites Volátiles/análisis , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/química , Tallos de la Planta/química , Terpenos/análisis
8.
Phytochemistry ; 70(7): 924-34, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19467550

RESUMEN

A broad-based characterisation of a pharmacologically active dichloromethane extract from Isatis tinctoria leaves was carried out. For a comprehensive picture we also included the polar constituents of I. tinctoria (MeOH extract) and for comparative purposes, the taxonomically closely related plant I. indigotica. Diode array detector, evaporative light scattering detector, atmospheric pressure chemical ionisation and electrospray ionisation mass spectrometry, and electrospray ionisation time-of-flight mass spectrometry detectors were used in parallel to ensure a wide coverage of secondary metabolites with highly diverging analytical properties. Off-line microprobe nuclear magnetic resonance spectroscopy after peak purification by semi-preparative high-pressure liquid chromatography served for structure elucidation of some minor constituents. More than 65 compounds belonging to various structural classes such as alkaloids, flavonoids, fatty acids, porphyrins, lignans, carotenoids, glucosinolates and cyclohexenones were unambiguously identified, and tentative structures were proposed for additional compounds. Numerous compounds were identified for the first time in the genus Isatis, and an indolic alkaloid was discovered.


Asunto(s)
Isatis/química , Plantas Medicinales/química , Alcaloides/análisis , Carotenoides/análisis , Cromatografía Líquida de Alta Presión , Ciclohexanonas/análisis , Espectroscopía de Resonancia por Spin del Electrón , Ácidos Grasos/análisis , Flavonoides/análisis , Glucósidos/análisis , Alcaloides Indólicos/análisis , Lignanos/análisis , Estructura Molecular , Hojas de la Planta/química , Porfirinas/análisis
9.
Planta ; 229(1): 225-33, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18830707

RESUMEN

The mycosporine-like amino acid (MAA) profile of a rice-field cyanobacterium, Anabaena doliolum, was studied under PAR and PAR + UVR conditions. The high-performance liquid chromatographic analysis of water-soluble compounds reveals the biosynthesis of three MAAs, mycosporine-glycine (lambda (max) = 310 nm), porphyra-334 (lambda (max) = 334 nm) and shinorine (lambda (max) = 334 nm), with retention times of 4.1, 3.5 and 2.3 min, respectively. This is the first report for the occurrence of mycosporine-glycine and porphyra-334 in addition to shinorine in Anabaena strains studied so far. The results indicate that mycosporine-glycine (monosubstituted) acts as a precursor for the biosynthesis of the bisubstituted MAAs shinorine and porphyra-334. Mycosporine-glycine was under constitutive control while porphyra-334 and shinorine were induced by UV-B radiation, indicating the involvement of UV-regulated enzymes in the biotransformation of MAAs. It seems that A. doliolum is able to protect its cell machinery from UVR by synthesizing a complex set of MAAs and thus is able to survive successfully during the summer in its natural brightly lit habitats.


Asunto(s)
Anabaena/efectos de la radiación , Ciclohexanoles/análisis , Ciclohexanonas/análisis , Ciclohexilaminas/análisis , Glicina/análogos & derivados , Oryza/microbiología , Rayos Ultravioleta , Cromatografía Líquida de Alta Presión , Glicina/análisis , Extractos Vegetales/análisis , Análisis Espectral
10.
Planta Med ; 74(7): 764-72, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18496783

RESUMEN

Extracts from saffron, the dried stigmata from Crocus sativus L., are being used more and more in preclinical and clinical trials for the treatment of cancer and depression. Because of the known quality problems of saffron, HPLC methods on RP(18) 2.5 microm and monolithic RP(18) material have been developed and validated for quality control including the quantification of crocins 1 to 5, crocetin, picrocrocin and the degradation products, the CIS-crocins. Additionally, a GC-MS method has allowed detection and quantification of the volatile compounds from the pentane extract of saffron. Both systems together allowed the comprehensive characterisation of saffron herbal material and extracts for clinical/preclinical trials. For effective preparation of the respective reference standards, a fast centrifugal partition chromatography (FCPC) method was developed allowing the quick isolation of crocins 1, 2, 5 and picrocrocin in good yields. Using these chromatographic methods and the reference standards, a representative survey of saffron from the global market indicated a high variability of quality, especially concerning the amounts of volatile compounds in saffron samples. A specification for high-quality saffron of >20% crocins, >6% picrocrocin and not less than 0.3% of volatiles, calculated as sum of safranal, isophorone and ketoisophorone, was developed. Because no detailed pharmacological studies are available to explain the clinical effects of saffron for the treatment of cancer and depression, receptor binding studies were performed. Saffron extracts and crocetin had a clear binding capacity at the PCP binding side of the NMDA receptor and at the sigma(1) receptor, while the crocins and picrocrocin were not effective. These data could give biochemical support for the above-mentioned pharmacological effects of saffron.


Asunto(s)
Carotenoides/análisis , Crocus/química , Extractos Vegetales/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Receptores sigma/metabolismo , Carotenoides/metabolismo , Ciclohexanonas/análisis , Ciclohexenos/análisis , Flores/química , Glucósidos/análisis , Extractos Vegetales/normas , Control de Calidad , Estándares de Referencia , Terpenos/análisis , Vitamina A/análogos & derivados , Receptor Sigma-1
11.
J Agric Food Chem ; 52(25): 7525-31, 2004 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-15675799

RESUMEN

Laurus nobilis L. leaves are widely used in cooking and in folk medicine. Five new megastigmane glucosides (2-4, 7, and 9) named laurosides A-E and a new phenolic glucoside 12 were isolated from the methanolic extract of L. nobilis L. leaves, along with 10 known components: megastigmane (5), megastigmane glucosides (1, 6, 8, 10, and 11), aromatic compounds (13 and 14), and flavonoids (15 and 16). The structures and relative stereochemistry have been elucidated by one- and two-dimensional nuclear magnetic resonance experiments ((1)H and (13)C NMR, DEPT, correlation spectroscopy, heteronuclear multiple quantum correlation, heteronuclear multiple bond correlation, and nuclear Overhauser enhancement spectroscopy) and by chemical derivatization. The effect of isolated compounds on nitric oxide production in lipopolysaccharide-activated murine macrophages were examined.


Asunto(s)
Ciclohexanonas/farmacología , Glucósidos/farmacología , Laurus/química , Óxido Nítrico/antagonistas & inhibidores , Norisoprenoides/farmacología , Fenoles/farmacología , Hojas de la Planta/química , Animales , Línea Celular , Ciclohexanonas/análisis , Ciclohexanonas/química , Glucósidos/análisis , Glucósidos/química , Macrófagos/metabolismo , Espectroscopía de Resonancia Magnética , Metanol , Ratones , Estructura Molecular , Óxido Nítrico/biosíntesis , Óxido Nítrico Sintasa/metabolismo , Óxido Nítrico Sintasa de Tipo II , Norisoprenoides/análisis , Norisoprenoides/química , Fenoles/análisis , Fenoles/química , Extractos Vegetales/química
12.
J Agric Food Chem ; 48(10): 4821-5, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11052739

RESUMEN

A methanolic extract from dill (Anethum graveolens) herb was subjected to XAD-2 adsorption chromatography. The methanolic eluate was fractionated with the all liquid chromatographic technique of multilayer coil countercurrent chromatography (MLCCC). After acetylation of MLCCC subfractions and flash chromatography, final purification of dill herb constituents was achieved by preparative and/or analytical HPLC. Nine compounds were obtained in pure form, including the beta-D-glucopyranosides of 9-hydroxypiperitone, p-menth-2-ene-1,6-diol, and 8-hydroxygeraniol. Structure elucidation is based on electrospray ionization ion trap multiple mass spectrometry (ESI-MS/MS) as well as one- and two-dimensional nuclear magnetic resonance spectroscopy.


Asunto(s)
Apiaceae/química , Ciclohexanonas/análisis , Glucósidos/análisis , Cromatografía Líquida de Alta Presión , Contrainmunoelectroforesis , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Extractos Vegetales/análisis
13.
Zhongguo Zhong Yao Za Zhi ; 21(4): 206-7, 254, 1996 Apr.
Artículo en Chino | MEDLINE | ID: mdl-9208548

RESUMEN

The contents of dryocrassin in Rhizoma Dryopteris Crassirhizomae were determined by TLC-scanning in a period of two years of storage. Phloroglucinol content was calculated by area normalization method. The results show that in contrast with the fresh crude drugs of Rhizoma Dryopteris Crassirhizomae, the contents of dryocrassin in the crude drugs of one year and two years of storage have reduced by 22% and 27% respectively, and phloroglucinol contents have reduced by 2% and 8% respectively.


Asunto(s)
Compuestos de Bencilideno/análisis , Ciclohexanonas/análisis , Medicamentos Herbarios Chinos/química , Floroglucinol/análisis , Cromatografía en Capa Delgada , Densitometría , Almacenaje de Medicamentos , Control de Calidad , Factores de Tiempo
14.
J Nat Prod ; 55(2): 221-4, 1992 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1624942

RESUMEN

Major components of MeOH extracts from the plant roots of Cnidosculus urens purified by cc and tlc and crystallization were lupeol acetate and the previously unreported compounds isoxochitlolone [1] and xochitloldione [2], which were identified through mass, ir, nmr, and uv spectroscopy and X-ray crystallography. In preliminary testing, isoxochitlolone has been found to be active against Escherichia coli and Staphylococcus aureus.


Asunto(s)
Antibacterianos/aislamiento & purificación , Ciclohexanonas/aislamiento & purificación , Fenoles/aislamiento & purificación , Plantas Medicinales/química , Antibacterianos/análisis , Antibacterianos/farmacología , Cromatografía en Capa Delgada , Cristalización , Ciclohexanonas/análisis , Ciclohexanonas/farmacología , Escherichia coli/efectos de los fármacos , México , Pruebas de Sensibilidad Microbiana , Fenoles/análisis , Fenoles/farmacología , Staphylococcus aureus/efectos de los fármacos , Difracción de Rayos X
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