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1.
J Chromatogr Sci ; 56(9): 812-818, 2018 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-29897423

RESUMEN

The leaves of the aromatic neotropical shrub Hedyosmum brasiliense are employed popularly as a sedative, aphrodisiac and as a substitute for green tea. Sesquiterpene lactones and phenolic compounds were characterized as the main compounds of its aqueous extract, and some biological investigation demonstrated its anxiolytic, antidepressant and hypnotic effects. The quantification of podoandin, onoseriolide and rosmarinic acid in its infused tea was achieved by means of ultra high performance liquid chromatography coupled to a electronspray ionization interface and a high resolution mass detector. Quantification of the analytes was performed employing the areas of the extracted ion chromatograms of the analytes, negative ion mode for rosmarinic acid (1) and positive mode for podoandin (2) and onoseriolide (3). The method was validated by evaluating specificity, linearity, precision and accuracy and has been found to be sensitive, precise and accurate. When applied to analyze the hot water infusion extract of H. brasiliense, compounds 1, 2 and 3 were obtained to be 188 ± 1.45 mg/g, 1.9 ± 0.15 mg/g and 1.7 ± 0.02 mg/g of extract, respectively. The H. brasiliense tea was found to be a good source of the rosmarinic acid, also widely employed in the cosmetic industry.


Asunto(s)
4-Butirolactona/análogos & derivados , Cromatografía Liquida/métodos , Cinamatos/análisis , Cicloheptanos/análisis , Depsidos/análisis , Sesquiterpenos/análisis , Tracheophyta/química , 4-Butirolactona/análisis , Modelos Lineales , Extractos Vegetales/química , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrometría de Masas en Tándem/métodos , Ácido Rosmarínico
2.
Nat Prod Res ; 32(23): 2803-2816, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28982254

RESUMEN

The biotransformation of the lignan (-)-cubebin by filamentous fungi Aspergillus terreus and Aspergillus niger is an efficient bioprocess for obtaining (-)-hinokinin and (-)-parabenzlactone. The relevance of getting (-)-hinokinin is due to its promising effect against oral pathogens, especially S. sanguinis (both MIC and MBC 12.5 µg/mL), and other previous reported effects against Chagas disease and as anti-inflammatory. The advantage of using fungal transformation is the use of non-toxic and/or non-pollutant reagents and/or solvents in comparison with semi-synthesis. Microbial transformation of (-)-cubebin is also important to evaluate its human metabolism, since Aspergillus species are capable of mimicking P450 reactions, providing possible products of the metabolism, which is important in the assessment of its efficacy and safety. Furthermore, the present study describes a reliable RP-HPLC method to perform quantification of (-)-hinokinin in fungal extracts. It is simple, fast, selective, linear, precise, accurate and robust according to validation guidelines.


Asunto(s)
4-Butirolactona/análogos & derivados , Aspergillus/metabolismo , Bacterias/efectos de los fármacos , Benzodioxoles/metabolismo , Compuestos de Bencilo/metabolismo , Biotransformación , Lactonas/metabolismo , Lignanos/metabolismo , 4-Butirolactona/análisis , 4-Butirolactona/metabolismo , 4-Butirolactona/farmacología , Benzodioxoles/análisis , Benzodioxoles/farmacología , Compuestos de Bencilo/farmacología , Hongos , Humanos , Lactonas/farmacología , Lignanos/análisis , Lignanos/farmacología
3.
PLoS One ; 12(2): e0170281, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28151972

RESUMEN

Pilocarpus microphyllus Stapf ex Wardleworth (jaborandi, Rutaceae) is one of the most important Brazilian medicinal species owing to its content of pilocarpine (PIL), an alkaloid used for treating glaucoma and xerostomia. This species contains another alkaloid, epiisopiloturine (EPI), which has demonstrated effectiveness against schistosomiasis. The aim of this work was to assess seasonal changes of PIL and EPI in three populations of cultivated P. microphyllus from northeastern Brazil over one year, including the dry and rainy seasons. Alkaloid profiles were correlated to phenotypic and genetic patterns in the morphological and molecular characterizations. PIL was the primary alkaloid and its levels differed among populations in all months except September. The S01 population (green line) showed an especially high PIL content compared to populations S02 and S03 (traditional line), which had similar alkaloid contents. PIL content gradually decreased in the three populations in the rainy season.EPI content was significantly different between the green line (S01) and the traditional line (S02 and S03).S01 had a significantly lower EPI content in all months, demonstrating that it was not the best source for EPI extraction. Inter simple sequence repeat (ISSR) markers and morphological analyses clearly separated S01 from S02 and S03, in agreement with the alkaloid results. This study shows the first correlation between the chemical, morphological, and molecular markers of P. microphyllus and highlights the potential benefits of a multidisciplinary research approach aimed at supporting both industry and conservation of natural resources.


Asunto(s)
Alcaloides/análisis , Pilocarpus/química , Plantas Medicinales/química , 4-Butirolactona/análogos & derivados , 4-Butirolactona/análisis , Brasil , ADN de Plantas/genética , Genética de Población , Imidazoles/análisis , Repeticiones de Microsatélite , Pilocarpina/análisis , Pilocarpus/anatomía & histología , Pilocarpus/genética , Hojas de la Planta/anatomía & histología , Hojas de la Planta/química , Hojas de la Planta/genética , Plantas Medicinales/anatomía & histología , Plantas Medicinales/genética , Estaciones del Año
4.
Bull Environ Contam Toxicol ; 91(2): 160-4, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23722654

RESUMEN

A method was developed using matrix solid-phase dispersion, together with liquid chromatography with ultraviolet diode array detector for determination of carbofuran, difenoconazole, ß-cyfluthrin, spirodiclofen and thiophanate-methyl in stem of coconut palm. The best results were obtained using 2.0 g of stem, 1.6 g of Florisil as sorbent and cyclohexane:acetone mixture (4:1). The method was validated using stem samples spiked with pesticides at four concentration levels (0.05-2.0 µg/g). Average recoveries ranged from 70 % to 114.3 %, with relative standard deviations between 1.2 % and 19.2 %. Detection and quantification limits were in the ranges 0.02-0.03 and 0.05-0.1 µg/g, respectively.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Cocos/química , Residuos de Plaguicidas/análisis , Tallos de la Planta/química , Extracción en Fase Sólida/métodos , 4-Butirolactona/análogos & derivados , 4-Butirolactona/análisis , Acetona/química , Carbofurano/análisis , Ciclohexanos/química , Dioxolanos/análisis , Silicatos de Magnesio/química , Nitrilos/análisis , Piretrinas/análisis , Reproducibilidad de los Resultados , Compuestos de Espiro/análisis , Tiofanato/análisis , Triazoles/análisis
5.
J AOAC Int ; 95(1): 84-91, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22468345

RESUMEN

Z-Ligustilide (1) and Z-6,6',7,3'-alpha-diligustilide (2), two of the major active phthalides of the medicinal plant Ligusticum porteri (osha), were chosen for the development and validation of an HPLC-diode array detection method suitable for QC of the crude drug. The method used gradient elution to achieve separation on a Hibar RT LiChrospher 100 C18 column. The LOD values were 29 and 45 microg/mL, and the LOQs were 89 and 125 microg/mL, respectively. The method showed good intraday precision (%RSD: 0.7 for 1 and 3.1 for 2) and interday precision (%RSD: 1.2 for 1 and 1.8 for 2). The method was used for the analysis of 1 and 2 in crude drug samples and several herbal preparations from Mexico and the United States. Quantitative analysis showed that the content of the two phthalides varied significantly among the samples. All the samples contained higher concentrations of 1 (0.15-2.5%) than 2 (0.002-1.0%). The profiles of volatile compounds in the essential oil obtained by hydrodistillation and solid-phase microextraction of L. porteri roots were analyzed by GC-MS. Thirty one chemical constituents (> 99.7% of the total content) were identified in the essential oil, which was characterized by the presence of a high percentage of phthalides (44.61%) and sesquiterpenes (10.69%). The major light volatile components extracted by solid-phase microextraction were monoterpenes.


Asunto(s)
4-Butirolactona/análogos & derivados , Ligusticum/química , 4-Butirolactona/análisis , Benzofuranos , Cromatografía Líquida de Alta Presión , Cromatografía de Gases y Espectrometría de Masas/métodos , Indicadores y Reactivos , Límite de Detección , México , Extractos Vegetales/análisis , Preparaciones de Plantas/análisis , Raíces de Plantas/química , Estándares de Referencia , Análisis de Regresión , Reproducibilidad de los Resultados , Microextracción en Fase Sólida/métodos , Solventes , Estados Unidos
6.
J Dairy Res ; 78(1): 111-7, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21214967

RESUMEN

Nutritional value is a priority in new product development. Using vegetable or marine oils, rich in polyunsaturated fatty acids, in dairy beverage formulations is an option to provide the consumers with healthier products. However, these formulations are prone to oxidation, which is responsible for rapid flavour degradation and the development of potentially toxic reaction products during storage. Flaxseed lignans, secoisolariciresinol diglucoside (SDG), and its mammalian metabolites have antioxidant activity and could be used in beverage formulations to prevent oxidation. Commercially available SDG extract was added to the formulation of dairy beverages enriched with flaxseed oil. As an alternative approach, dairy beverages were produced from milk naturally rich in SDG metabolites obtained through the alteration of cow diet. Resistance to oxidation was determined from the kinetics of hexanal and propanal production during heat and light exposure treatments. Increasing SDG concentration in dairy beverage slightly reduced redox potential but had no effect on oxygen consumption during oxidation treatments. The presence of SDG in dairy beverage significantly improved resistance to heat- and light-induced oxidation. However, purified enterolactone, a mammalian metabolite from SDG, prevented oxidation at much lower concentrations. The use of milk from dairy cow fed flaxseed meal did not improve resistance to oxidation in dairy beverage. Enterolactone concentration in milk was increased by the experimental diet but it remained too low to observe any significant effect on dairy beverage oxidation.


Asunto(s)
Antioxidantes/administración & dosificación , Ácidos Grasos Insaturados/química , Lino/química , Alimentos Fortificados , Lignanos/administración & dosificación , Leche/química , 4-Butirolactona/análogos & derivados , 4-Butirolactona/análisis , 4-Butirolactona/metabolismo , 4-Butirolactona/farmacología , Animales , Butileno Glicoles/administración & dosificación , Butileno Glicoles/metabolismo , Bovinos , Dieta , Femenino , Glucósidos/administración & dosificación , Glucósidos/metabolismo , Calor , Lignanos/análisis , Lignanos/metabolismo , Lignanos/farmacología , Oxidación-Reducción , Estrés Oxidativo , Procesos Fotoquímicos
7.
Phytochem Anal ; 21(5): 428-33, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20310075

RESUMEN

INTRODUCTION: A large number of natural and synthetic compounds having butenolides as a core unit have been described and many of them display a wide range of biological activities. Butenolides from P. malacophyllum have presented potential antifungal activities but no specific, fast, and precise method has been developed for their determination. OBJECTIVE: To develop a methodology based on micellar electrokinetic chromatography to determine butenolides in Piper species. METHODOLOGY: The extracts were analysed in an uncoated fused-silica capillaries and for the micellar system 20 mmol/L SDS, 20% (v/v) acetonitrile (ACN) and 10 mmol/L STB aqueous buffer at pH 9.2 were used. The method was validated for precision, linearity, limit of detection (LOD) and limit of quantitation (LOQ) and the standard deviations were determined from the standard errors estimated by the regression line. RESULTS: A micellar electrokinetic chromatography (MEKC) method for determination of butenolides in extracts gave full resolution for 1 and 2. The analytical curve in the range 10.0-50.0 µg/mL (r(2) = 0.999) provided LOD and LOQ for 1 and 2 of 2.1/6.3 and 1.1/3.5 µg/mL, respectively. The RSD for migration times were 0.12 and 1.0% for peak area ratios with 100.0 ± 1.4% of recovery. CONCLUSIONS: A novel high-performance MEKC method developed for the analysis of butenolides 1 and 2 in leaf extracts of P. malacophyllum allowed their quantitative determined within an analysis time shorter than 5 min and the results indicated CE to be a feasible analytical technique for the quantitative determination of butenolides in Piper extracts.


Asunto(s)
4-Butirolactona/análogos & derivados , Piper/química , 4-Butirolactona/análisis , Cromatografía Líquida de Alta Presión , Cromatografía Capilar Electrocinética Micelar , Indicadores y Reactivos , Hojas de la Planta/química , Estándares de Referencia , Reproducibilidad de los Resultados , Soluciones
8.
J Food Sci ; 75(9): S506-12, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21535624

RESUMEN

Physicochemical attributes, aroma profile, and odor contribution of pineapple flesh were studied for the top, middle, and bottom cross-sections cut along the central axis of Gold cultivar pineapple. Relationships between volatile and nonvolatile compounds were also studied. Aroma profile constituents were determined by headspace solid-phase microextraction at 30 °C, followed by gas chromatography/mass spectrometry analysis. A total of 20 volatile compounds were identified and quantified. Among them, esters were the major components which accounted for 90% of total extracted aroma. Methyl butanoate, methyl 2-methyl butanoate, and methyl hexanoate were the 3 most abundant components representing 74% of total volatiles in pineapple samples. Most odor active contributors were methyl and ethyl 2-methyl butanoate and 2,5-dimethyl 4-methoxy 3(2H)-furanone (mesifuran). Aroma profile components did not vary along the fruit, but volatile compounds content significantly varied (P < 0.05) along the fruit, from 7560 to 10910 µg/kg, from the top to the bottom cross-sections of the fruit, respectively. In addition, most odor-active volatiles concentration increased from the top to the bottom 3rd of the fruit, concurrently with soluble solids content (SSC) and titratable acidity (TA) differences attributed to fruitlets distinct degree of ripening. Large changes in SSC/TA ratio and volatiles content throughout the fruit found through this study are likely to provoke important differences among individual fresh-cut pineapple trays, compromising consumer perception and acceptance of the product. Such finding highlighted the need to include volatiles content and SSC/TA ratio and their variability along the fruit as selection criteria for pineapples to be processed and quality assessment of the fresh-cut fruit.


Asunto(s)
Ananas/química , Frutas/química , Odorantes/análisis , Olfato , Compuestos Orgánicos Volátiles/análisis , 4-Butirolactona/análogos & derivados , 4-Butirolactona/análisis , Comportamiento del Consumidor , Productos Agrícolas/crecimiento & desarrollo , Ésteres/análisis , Manipulación de Alimentos/métodos , Cromatografía de Gases y Espectrometría de Masas , Humanos , Microextracción en Fase Sólida
9.
J Agric Food Chem ; 53(16): 6262-5, 2005 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-16076103

RESUMEN

The phytopathogen Erwinia psidii R. IBSBF 435T causes rot in branches, flowers, and fruits of guava (Psidium guajava L.), being responsible for crop losses, and has no effective control. It was demonstrated that this strain produces two compounds [S-(-)-N-hexanoyl and N-heptanoyl-homoserine lactone], both belonging to the class of quorum-sensing signaling substances. A protocol using gas chromatography-flame ionization detection with chiral stationary phase is described for the absolute configuration determination of a natural acyl-homoserine lactone. Biological assays with specific reporter and synthesis of identified substances are also described. This is the first report on the N-heptanoyl-homoserine lactone occurrence in the Erwinia genus.


Asunto(s)
4-Butirolactona/análogos & derivados , Erwinia/metabolismo , Enfermedades de las Plantas/microbiología , Psidium/efectos de los fármacos , 4-Butirolactona/análisis , 4-Butirolactona/química , Estructura Molecular
10.
Rev Latinoam Microbiol ; 37(1): 27-31, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7784729

RESUMEN

A new serogroup of Vibrio cholerae non-O1, O:139, has been implicated in recent epidemics. It was scanned with a factor A-specific fluoresceine-conjugated monoclonal antibody, searching for antigen determinants by laser flow cytometry. First, a group of gram-negative 4-amine-4, 6 dideoxy-D-mannose antigen-related microorganisms were tested to assess monoclonal antibody cross reactions. Later, a clear recognition of antigen determinants was found with this monoclonal antibody, on V. cholerae non-O1, O:136, Bengal, and MO45 strains, showing no cross reactions with the antigenically related non O1, O:22, and Inaba and Ogawa O1 strains. On the other hand, factor A of V. cholerae O1 strains was recognized by the specific monoclonal antibody and a discrete factor A on V. cholerae non-O1, O:139, Bengal and MO45 strains was detected.


Asunto(s)
4-Butirolactona/análogos & derivados , Citometría de Flujo/métodos , Sustancias de Crecimiento/análisis , Vibrio cholerae/clasificación , 4-Butirolactona/análisis , 4-Butirolactona/biosíntesis , Sustancias de Crecimiento/biosíntesis , Humanos , Rayos Láser , Serotipificación , Vibrio cholerae/metabolismo
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