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1.
Planta Med ; 77(9): 945-50, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21240842

RESUMEN

The gum resin of Commiphora wightii [(Hook. ex Stocks) Engl.] is an ayurvedic medicine for the treatment of arthritis, inflammation, obesity, lipid disorders, and cardiovascular diseases and is known as guggul. Morphologically, it is not easy to distinguish guggul from closely related gum resins of other plants. Reliability of the commercially available guggul is critical due to the high risk of adulteration. To check authenticity, a commercial guggul sample was investigated for its chemical markers and 17 metabolites were identified, including three new, 20(S),21-epoxy-3-oxocholest-4-ene (1), 8 ß-hydroxy-3,20-dioxopregn-4,6-diene (2), and 5-(13' Z-nonadecenyl)resorcinol (17) from the ethyl acetate soluble part. During the current study, compounds 14- 17 were identified as constituents of Mangifera indica gum, as an adulterant in the commercial guggul sample. This discovery highlighted the common malpractices in the trade of medicinal raw material in the developing world. The structures of the compounds were deduced by the spectroscopic technique and chemical methods, as well as by comparison with the reported data. The structure of 20(S),21-epoxy-3-oxocholest-4-ene (1) was also unambiguously deduced by single-crystal X-ray diffraction technique.


Asunto(s)
Commiphora/química , Hipolipemiantes/química , Hipolipemiantes/normas , Extractos Vegetales/química , Extractos Vegetales/normas , Gomas de Plantas/química , Gomas de Plantas/normas , Colestenos/química , Colestenos/aislamiento & purificación , Commiphora/clasificación , Cristalografía por Rayos X , Países en Desarrollo , Hipolipemiantes/aislamiento & purificación , India , Espectroscopía de Resonancia Magnética , Mangifera/química , Medicina Ayurvédica , Pakistán , Extractos Vegetales/aislamiento & purificación , Gomas de Plantas/aislamiento & purificación , Resinas de Plantas/química , Resinas de Plantas/aislamiento & purificación , Resinas de Plantas/normas , Difracción de Rayos X
2.
Zhongguo Zhong Yao Za Zhi ; 32(19): 2025-7, 2007 Oct.
Artículo en Chino | MEDLINE | ID: mdl-18161297

RESUMEN

OBJECTIVE: To study the fingerprint of dragon's blood resina draconis by high performance liquid chromatography. METHOD: The samples are extracted with methanol and separated on a Eclipse XDB-C18 column (4.6 mm x 150 mm, 5 microm) with the mobile phase of acetonitrile-H2O in gradient mode, and the flow rate was 1.0 mL x min(-1), the detection wavelength was 275 nm and the temperature of column was 40 degrees C. Loureirin B was used as the reference compound. RESULT: HPLC fingerprint of dragon's blood was established and the similarity of the fingerprint was compared. CONCLUSION: The method is simple, accurate, and can be used to control the quality of dragon's blood.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Dracaena/química , Extractos Vegetales/análisis , Plantas Medicinales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/normas , Control de Calidad , Reproducibilidad de los Resultados , Resinas de Plantas/análisis , Resinas de Plantas/aislamiento & purificación , Resinas de Plantas/normas
3.
Cytobios ; 104(407): 145-56, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11318510

RESUMEN

Butyl-methylmethacrylate resin mixtures were tested for brittleness-inducing factors in polymerised resin using a rapid quantitative scoring technique. The major source of brittleness was identified as the reducing agent dithiothreitol, which is commonly included in resin mixtures at 10 mM, to protect against tissue oxidation. Lowering the dithiothreitol content to 5 mM substantially reduced brittleness. Changing the 4:1 ratio of butyl- to methylmethacrylate to 9:1 or 3:2, and reducing the concentration of the catalyst, benzoin ethyl ether, to 0.25% also reduced dithiothreitol-induced brittleness. Polymerisation at temperatures close to 0 degrees C increased dithiothreitol-induced brittleness, but this was controlled in the 4:1 and 9:1 resin mixtures by lowering the catalyst concentration from 0.5 to 0.25%. Degassing the resin mixture with nitrogen gas prior to polymerisation did not reduce brittleness. Immunolabelled onion roots which were embedded using the 3:2 resin mixture ratio, 5 mM dithiothreitol and the 0.25% catalyst concentration, showed excellent preservation of cortical microtubule arrays.


Asunto(s)
Metilmetacrilatos/síntesis química , Resinas de Plantas/síntesis química , Resinas de Plantas/normas , Ditiotreitol/farmacología , Técnica del Anticuerpo Fluorescente/métodos , Metilmetacrilatos/química , Metilmetacrilatos/normas , Microscopía Fluorescente/métodos , Cebollas , Raíces de Plantas/ultraestructura , Docilidad/efectos de los fármacos , Resinas de Plantas/química , Adhesión del Tejido
4.
Blood Purif ; 18(3): 231-6, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10859426

RESUMEN

Paired filtration dialysis is a modified form of hemodiafiltration with a double-chamber hollow fiber. Convection is separated from diffusion, eliminating the potential risk of backfiltration (which can contain endotoxin or cytokine-inducing substances). The regeneration of high volumes of plasma ultrafiltrate obtained in the first filter allows a large plasma volume to be treated, and at the same time enables the return of many beneficial substances such as hormones, small peptides and many vitamins. Ultrafiltrate is regenerated with a charcoal-resin device and reinfused to the patient. Hemodiafiltration with on-line endogenous reinfusion is an easy and safe procedure. In addition, the method avoids risks associated with exogenous fluid infusion (endotoxin, pyrogens), allows exchange at no extra costs of large volumes of fluids and reduction in storage of fluid bags. Clinical advantages also include infusion of physiological fluid containing bicarbonate and calcium, good clinical tolerance and cardiovascular stability.


Asunto(s)
Hemodiafiltración/métodos , Adsorción , Diseño de Equipo , Hemodiafiltración/instrumentación , Hemodiafiltración/normas , Humanos , Infusiones Intravenosas/métodos , Infusiones Intravenosas/normas , Resinas de Plantas/normas
7.
Crit Rev Food Sci Nutr ; 17(3): 189-258, 1982.
Artículo en Inglés | MEDLINE | ID: mdl-6756789

RESUMEN

Ginger is used in more ways than any other spice. This monograph, published in two parts, comprehensively reviews production, trade, processing, chemistry, and evaluation of quality. Botany, world varieties, agronomy, crop improvement, and potential are reviewed briefly with emphasis on the yield of functional components. Processing for the market, international trade patterns and factors influencing them are discussed. Derived products such as ginger powder, syruped ginger, volatile oil, and oleoresin are discussed in greater detail. The increasing world demand for quality products of added value such as the oleoresin and volatile oil show the prospects for their production in the growing countries. The chemistry of the components which contribute aroma and pungency that characterize ginger is critically reviewed. The second part deals with evaluation of quality. The physicochemical parameters prescribed as a measure of quality for ginger and its products in the existing standards, can assure only hygienic quality and purity, and possibly the source, when new parameters such as GC-finger prints are included. The importance of sensorily evaluating flavor quality is emphasized to understand the variation in flavor quality required by the industrial and retail markets. Related areas, such as problems in sensory evaluation of intense flavored substances, objective flavor profile analysis, correlation of instrumental and sensory data are discussed, and our recent work in this area is summarized. Areas where more research is needed are indicated. Other areas briefly discussed are functional, physiological, and toxicological properties in use of ginger; biosynthetic aspects of components stimulating flavor; structure and pungency and chemistry of spices from allied species and genera. A comprehensive bibliography is provided to aid in further study and research.


Asunto(s)
Condimentos , Fenómenos Químicos , Química , Condimentos/análisis , Condimentos/normas , Condimentos/toxicidad , Tecnología de Alimentos , India , Modelos Biológicos , Odorantes/análisis , Aceites/análisis , Aceites Volátiles/análisis , Plantas/metabolismo , Resinas de Plantas/normas , Gusto
8.
Am Ind Hyg Assoc J ; 41(12): 901-7, 1980 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7468460

RESUMEN

Several thousand raw materials ranging from naturally occurring minerals to highly toxic biocidal agents are employed in the manufacture of coatings and resins. The batch-type operations of this industry require employees to handle many different materials each day, so an easily recognizable and effective hazardous materials warning system is requisite. Such a system has been developed in the Coatings and Resins Division of PPG Industries and is called the "Safety and Health Index System". With this system, it is now possible for PPG employees to know the potential health, flammability and reactivity hazards associated with each bag or drum they may handle and take the necessary precautions to protect themselves.


Asunto(s)
Etiquetado de Productos/métodos , Resinas de Plantas/normas , Humanos , Enfermedades Profesionales/prevención & control , Equipos de Seguridad , Riesgo
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