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1.
Planta Med ; 76(15): 1758-61, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20379957

RESUMEN

One new cucurbitane-type triterpenoid glycoside, momordicoside U (1), together with five known cucurbitane-type triterpenoids and related glycosides, 3ß,7 ß,25-trihydroxycucurbita-5,23 (E)-dien-19-al (2), momordicine I (3), momordicine II (4), 3-hydroxycucurbita-5,24-dien-19-al-7,23-di-O-ß-glucopyranoside (5), and kuguaglycoside G (6), were isolated from the whole plant of Momordica charantia. Their structures were determined by chemical and spectroscopic methods. Momordicoside U (1) was evaluated for insulin secretion activity in an in vitro insulin secretion assay and displayed moderate activity.


Asunto(s)
Células Secretoras de Insulina/efectos de los fármacos , Insulina/metabolismo , Momordica charantia/química , Saponinas/farmacología , Triterpenos/farmacología , Animales , Línea Celular , Glicósidos/química , Glicósidos/aislamiento & purificación , Secreción de Insulina , Ratones , Resonancia Magnética Nuclear Biomolecular , Saponinas/química , Saponinas/aislamiento & purificación , Triterpenos/química , Triterpenos/aislamiento & purificación
2.
Food Chem Toxicol ; 46(1): 168-74, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17822821

RESUMEN

Kava (Piper methysticum) is a member of the pepper family and has been cultivated by South Pacific islanders for centuries and used as a social and ceremonial drink. Traditionally, kava extracts are prepared by grinding or chewing the rhizome and mixing with water and coconut milk. The active constituents of kava are a group of approximately 18 compounds collectively referred to as kavalactones or kava pyrones. Kawain, dihydrokawain, methysticin, dihydromethysticin, yangonin, and desmethoxyyangonin are the six major kavalactones. Kava beverages and other preparations are known to be anxiolytic and are used for anxiety disorders. Dietary supplements containing the root of the kava shrub have been implicated in several cases of liver toxicity in humans, including several who required liver transplants after using kava supplements. In order to study the toxicity and mutagenicity, two commercial samples of kava, Kaviar and KavaPure, and the six pure kavalactones including both D-kawain and DL-kawain, were evaluated in L5178Y mouse lymphoma cells. Neither the kava samples nor the kavalactones induced a mutagenic response in the L5178Y mouse lymphoma mutation assay with the addition of human liver S9 activation.


Asunto(s)
Citotoxinas/toxicidad , Kava/toxicidad , Lactonas/toxicidad , Mutágenos , Animales , Línea Celular Tumoral , Cromatografía Líquida de Alta Presión , Citotoxinas/química , Humanos , Kava/química , Lactonas/química , Hígado/metabolismo , Hígado/ultraestructura , Linfoma/genética , Espectrometría de Masas , Ratones , Pruebas de Mutagenicidad , Mutación/efectos de los fármacos , Mutación/genética , Extractos Vegetales/toxicidad , Fracciones Subcelulares/metabolismo , Fracciones Subcelulares/ultraestructura
3.
J AOAC Int ; 90(2): 465-9, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17474518

RESUMEN

Rapid capillary gas chromatography (GC) with flame-ionization detection was used to determine the cellular fatty acid profiles of Francisella tularensis. Two subspecies of F. tularensis, the live vaccine strain (LVS) derived from holarctica and a novicida strain Utah 112 (U112), were used to compare the extracted fatty acid methyl esters (FAMEs). A data set for the 2 subspecies was prepared using fatty acid profiles of bacteria grown on 2 types of media, Mueller-Hinton and cysteine heart agar supplemented with 5% rabbit blood (CHAB), and harvested at various time intervals (Day 1 through Day 4) with replicates prepared on different days. A total of 204 samples were analyzed. The results showed that these fatty acid quantitative profiles were unique for each of the subspecies and could be used as a fingerprint for the organism. It was determined by this rapid method that approximately 88% of the fatty acids in both the LVS and U112 strains included 6 saturated fatty acids: 10:0, 12:0, 14:0, 16:0, 18:0, and 20:0; and 4 hydroxy fatty acids 10:0 2OH, 16:0 3OH, 17:0 3OH, and 18:0 3OH. Data analysis and determination of clustering were performed by principal component analysis (PCA) and soft independent modeling of class analogy (SIMCA). Both PCA and SIMCA showed clear separation of the LVS and U112 strain and would be useful for prediction of unknowns. It was determined that the incubation time can be reduced from 48 to 24 h, and results are highly predictive for the identification of F. tularensis. In summary, analysis of FAMEs from F. tularensis subspecies LVS and U112 grown on CHAB or Mueller-Hinton media, and using a rapid GC method can provide a sensitive procedure for identification of these organisms.


Asunto(s)
Técnicas de Tipificación Bacteriana , Ácidos Grasos/química , Francisella tularensis/metabolismo , Agar/química , Animales , Proteínas Bacterianas/análisis , Proteínas Bacterianas/metabolismo , Técnicas de Química Analítica , Análisis por Conglomerados , Cisteína/química , Ésteres/química , Microscopía Electrónica , Análisis de Componente Principal , Conejos , Factores de Tiempo
4.
Food Chem Toxicol ; 43(11): 1619-25, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16040181

RESUMEN

Chromium picolinate is one of the most commonly used chromium dietary supplements available in the United States, and it has been marketed to consumers for use in weight loss, increasing muscle mass, and lowering serum cholesterol. Chromium picolinate is a synthetic compound that provides a bioavailable form of Cr(III) that is absorbed better than dietary chromium. However, there are several reports that it can have adverse effects. In order to study the mechanism of observed cellular toxicity and mutagenicity, chromium picolinate and its component compounds, chromium (III) chloride and picolinic acid, were evaluated in Salmonella typhimurium and L5178Y mouse lymphoma cells. Neither chromium picolinate nor chromium chloride induced a mutagenic response in S. typhimurium. However, in the L5178Y mouse lymphoma mutation assay, chromium picolinate induced mutagenic responses without and with the addition of S9.


Asunto(s)
Linfoma/genética , Mutágenos , Ácidos Picolínicos/toxicidad , Salmonella typhimurium/genética , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cromo/toxicidad , Cricetinae , Técnicas In Vitro , Hígado/efectos de los fármacos , Hígado/metabolismo , Linfoma/patología , Mesocricetus , Ratones , Pruebas de Mutagenicidad , Ratas , Ratas Sprague-Dawley , Salmonella typhimurium/efectos de los fármacos , Ensayo de Tumor de Célula Madre
5.
J Agric Food Chem ; 53(3): 566-73, 2005 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-15686403

RESUMEN

Cold-pressed marionberry, boysenberry, red raspberry, and blueberry seed oils were evaluated for their fatty acid composition, carotenoid content, tocopherol profile, total phenolic content (TPC), oxidative stability index (OSI), peroxide value, and antioxidant properties. All tested seed oils contained significant levels of alpha-linolenic acid ranging from 19.6 to 32.4 g per 100 g of oil, along with a low ratio of n-6/n-3 fatty acids (1.64-3.99). The total carotenoid content ranged from 12.5 to 30.0 micromoles per kg oil. Zeaxanthin was the major carotenoid compound in all tested berry seed oils, along with beta-carotene, lutein, and cryptoxanthin. Total tocopherol was 260.6-2276.9 mumoles per kg oil, including alpha-, gamma-, and delta-tocopherols. OSI values were 20.07, 20.30, and 44.76 h for the marionberry, red raspberry, and boysenberry seed oils, respectively. The highest TPC of 2.0 mg gallic acid equivalents per gram of oil was observed in the red raspberry seed oil, while the strongest oxygen radical absorbance capacity was in boysenberry seed oil extract (77.9 micromol trolox equivalents per g oil). All tested berry seed oils directly reacted with and quenched DPPH radicals in a dose- and time-dependent manner. These data suggest that the cold-pressed berry seed oils may serve as potential dietary sources of tocopherols, carotenoids, and natural antioxidants.


Asunto(s)
Antioxidantes/análisis , Arándanos Azules (Planta)/química , Ácidos Grasos/análisis , Aceites de Plantas/química , Rosaceae/química , Semillas/química , Carotenoides/análisis , Frutas/química , Oxidación-Reducción , Fenoles/análisis , Tocoferoles/análisis , Ácido alfa-Linolénico/análisis
6.
Nutr Rev ; 60(12): 391-406, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12521144

RESUMEN

Fortification of cereal flours may be a useful public health strategy to combat iron deficiency. Cereal flours that are used shortly after production (e.g., baking flour) can be fortified with soluble iron compounds, such as ferrous sulfate, whereas the majority of flours stored for longer periods is usually fortified with elemental iron powders to avoid unacceptable sensory changes. Elemental iron powders are less well absorbed than soluble iron compounds and they vary widely in their absorption depending on manufacturing method and physicochemical characteristics. Costs vary with powder type, but elemental iron powders are generally less expensive than ferrous sulfate. This review evaluates the usefulness of the different elemental iron powders based on results from in vitro studies, rat assays, human bioavailability studies, and efficacy studies monitoring iron status in human subjects. It concludes that, at the present time, only electrolytic iron powder can be recommended as an iron fortificant. Because it is only approximately half as well absorbed as ferrous sulfate, it should be added to provide double the amount of iron.


Asunto(s)
Anemia Ferropénica/prevención & control , Grano Comestible , Alimentos Fortificados , Compuestos de Hierro/administración & dosificación , Hierro de la Dieta/administración & dosificación , Animales , Disponibilidad Biológica , Harina , Humanos , Absorción Intestinal , Compuestos de Hierro/farmacocinética , Compuestos de Hierro/uso terapéutico , Hierro de la Dieta/farmacocinética , Hierro de la Dieta/uso terapéutico
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