RESUMEN
A potent antioxidant, resveratrol (3,4',5-trihydroxystilbene), was extracted using 80% methanol from peanut roots (Arachis hypogaea L.), isolated with a solid-phase extraction column, purified by a semipreparative HPLC, and identified with 1H NMR and MS. The highest and lowest resveratrol contents in the peanut roots of 2000 fall and 2001 spring crops were 1.330 and 0.130 mg/g and 0.063 and 0.015 mg/g, respectively. When the dehydrated peanut root powders of spring and fall crops were combined and cooked with pork-fat patties (1%, w/w) and the separated oils were stored at 60 degrees C for conjugated diene hydroperoxide (CDHP) determination, CDHP contents of the control oils increased after 3 days of storage, whereas the contents in the peanut root-treated oils of spring and fall crops did not increase after 9 and 15 days of storage, respectively. It is of merit to find that peanut roots, usually left in the field as agricultural waste, contain resveratrol and bear potent antioxidative activity.
Asunto(s)
Arachis/química , Raíces de Plantas/química , Estilbenos/análisis , Antioxidantes/análisis , Cromatografía Líquida de Alta Presión , Peróxido de Hidrógeno , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Aceite de Cacahuete , Aceites de Plantas/química , Resveratrol , Estaciones del Año , Estilbenos/aislamiento & purificaciónRESUMEN
Five new constituents including a flavonoid, artemisidin A (1), and four coumarins, artemicapins A (2), B (3), C (4) and D (5), together with 70 known compounds (6-75), have been isolated and characterized from the aerial part of Artemisia capillaris. The structures of these compounds were determined from spectral analyses and/or chemical evidence. Among them, 15 compounds (3, 6, 10, 18. 30-32, 38-41, 44, 45, 51, and 55) showed antiplatelet aggregation activity and three compounds (10, 17, and 51) demonstrated significant activity against HIV replication in H9 lymphocytic cells.
Asunto(s)
Acetileno/análogos & derivados , Fármacos Anti-VIH/aislamiento & purificación , Artemisia/química , Plantas Medicinales , Inhibidores de Agregación Plaquetaria/aislamiento & purificación , Acetileno/farmacología , Animales , Plaquetas/efectos de los fármacos , Ácidos Cafeicos/farmacología , Cumarinas/farmacología , Espectroscopía de Resonancia Magnética , Estructura Molecular , Inhibidores de Agregación Plaquetaria/farmacología , Conejos , EspectrofotometríaRESUMEN
One new biphenyl ether, aristogin C (1), and two new porphyrins, aristophylls A (2) and B (3), as well as 11 known compounds, were isolated from the leaves of Aristolochia elegans. Their structures were elucidated according to the spectroscopic (NMR and MS) analyses or by comparison with literature values.
Asunto(s)
Éteres Fenílicos/química , Plantas Medicinales/química , Porfirinas/química , Cromatografía Líquida de Alta Presión , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Éteres Fenílicos/aislamiento & purificación , Hojas de la Planta/química , Porfirinas/aislamiento & purificación , Espectrofotometría Infrarroja , Espectrofotometría UltravioletaRESUMEN
Reinvestigation of the root of Rhinacanthus nasutus afforded, in addition to rhinacanthin-A to -D reported previously, two new dimethyldihydropyranonaphthoquinone esters (5, 6) and eight new 2-hydroxy-1,4-naphthoquinone esters (7-14) were isolated. The stereochemistry of rhinacanthin-A was determined as the R configuration. Compounds rhinacanthin-G to -N, belong to a class of 2-hydroxy-3-(3-hydroxy-2,2-dimethylpropyl)-1,4-naphthoquinone esters, and so far have been isolated only in this plant. Their biosynthesis is also discussed.
Asunto(s)
Antivirales/aislamiento & purificación , Ésteres/aislamiento & purificación , Naftoquinonas/aislamiento & purificación , Plantas Medicinales/química , Antihipertensivos/química , Antihipertensivos/aislamiento & purificación , Antivirales/química , Ésteres/química , Espectroscopía de Resonancia Magnética , Naftoquinonas/químicaRESUMEN
The continuing investigation of the root of Rhinacanthus nasutus afforded a 1,4-naphthoquinone ester, rhinacanthin-Q, accompanied by twenty-four known compounds. The structure was elucidated on the basis of spectroscopic analyses. The cytotoxicity and antiplatelet effect of this compound was also discussed.
Asunto(s)
Naftoquinonas/aislamiento & purificación , Naftoquinonas/farmacología , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Plantas Medicinales/química , Humanos , Células KB/efectos de los fármacos , Naftoquinonas/química , Resonancia Magnética Nuclear Biomolecular , Extractos Vegetales/química , Raíces de Plantas/química , Agregación Plaquetaria/efectos de los fármacos , Inhibidores de Agregación Plaquetaria/farmacologíaRESUMEN
Five new carbazole alkaloids, clausines B, E, H, I and K, as well as 22 known compounds, were isolated from the stem bark of Clausena excavata. The structures were established from spectral data and chemical transformation. These compounds showed significant inhibition of rabbit platelet aggregation and caused vasocontraction. The crude methanol extract, partitioned layers and chromatographic fractions revealed the presence of promotive and inhibitive constituents, simultaneously. These results might explain the philosophy of use in Chinese medicine, in that the dose and content variation in a prescription produced different, promotive or inhibitive, effects on therapy.