Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Más filtros











Intervalo de año de publicación
1.
J Sep Sci ; 45(14): 2478-2487, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35562848

RESUMEN

A new method based on Ultraviolet spectrophotometry was developed and compared with that based on high-performance liquid chromatography for the determination and quantification of anthraquinones in the extracts of Rhamnus purshiana bark. A validated quantitative analysis of cascaroside A, cascaroside B, emodin, and aloe-emodin in these herbal products has been previously performed using high-performance liquid chromatography coupled with a diode array detector. In the high-performance liquid chromatography analysis, all the anthraquinones showed satisfactory regression (r2 > 0.98) within the test ranges, and the recovery was in the range of 94-117%. The limits of detection and quantification were 0.008-0.010 and 0.029-0.035 µg/mL, respectively. Hierarchical cluster analysis and principal component analysis showed differences in the anthraquinones determined from herbal samples. Subsequently, a simple and low-cost ultraviolet spectrophotometric methodology for the quantitative analysis of the same compounds in the extracts was applied, and all the contents were determined. A paired t-test confirmed that there were no significant differences between the two methods. Our results revealed that the developed method is simple and provides the ability to discriminate and control the quality of anthraquinones in herbal products.


Asunto(s)
Emodina , Rhamnus , Antraquinonas/química , Cromatografía Líquida de Alta Presión/métodos , Emodina/análisis , Rhamnus/química , Espectrofotometría Ultravioleta
2.
Oxid Med Cell Longev ; 2018: 2390234, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30057674

RESUMEN

There have been few studies on the pharmacological properties of Rhamnus sphaerosperma var. pubescens, a native Brazilian species popularly known as "fruto-de-pombo." The aim of this study was to investigate the scavenging capacity of emodin, physcion, and the ethanolic crude extract of Rhamnus sphaerosperma var. pubescens against reactive oxygen and nitrogen species, as well as their role and plausible mechanisms in prompting cell death and changes in AKT phosphorylation after cervical (SiHa and C33A) and oral (HSC-3) squamous cell carcinoma treatments. Emodin was shown to be the best scavenger of NO• and O2•-, while all samples were equally effective in HOCl/OCl- capture. Emodin, physcion, and the ethanolic extract all exhibited cytotoxic effects on SiHa, C33A, HSC-3, and HaCaT (immortalized human keratinocytes, nontumorigenic cell line), involving mixed cell death (apoptosis and necrosis) independent of the caspase activation pathway. Emodin, physcion, and the ethanolic extract increased intracellular oxidative stress and DNA damage. Emodin decreased the activation of AKT in all tumor cells, physcion in HSC-3 and HaCaT cells, and the ethanolic extract in C33A and HaCaT cells, respectively. The induction of cancer cell death by emodin, physcion, and the ethanolic crude extract of Rhamnus sphaerosperma var. pubescens was related to an increase in intracellular oxidative stress and DNA damage and a decrease in AKT activation. These molecules are therefore emerging as interesting candidates for further study as novel options to treat cervical and oral carcinomas.


Asunto(s)
Carcinoma de Células Escamosas/metabolismo , Emodina/análogos & derivados , Emodina/farmacología , Extractos Vegetales/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Rhamnus/química , Apoptosis/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Daño del ADN/efectos de los fármacos , Humanos , Estrés Oxidativo/efectos de los fármacos
3.
Nat Prod Res ; 32(3): 366-369, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28745519

RESUMEN

Different from works described in the literature, which use expansive analytical methods to separation of anthraquinones derivatives (AQs), this communication reported a simple and inexpensive methodology to get them. In this way, the expensive commercial AQs: Chrysophanol, physcione and emodine were extracted from plant material (Rhamnus frangula L.) and isolated by classical column chromatography technique under optimised binary mobile phase gradients (CHCl3 : AcOEt(a), a = 1 to 5%) in excellent yields.


Asunto(s)
Antraquinonas/aislamiento & purificación , Rhamnus/química , Antraquinonas/análisis , Cromatografía/métodos , Emodina/análogos & derivados , Emodina/análisis , Emodina/aislamiento & purificación , Métodos
4.
Nat Prod Lett ; 15(4): 243-51, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11833619

RESUMEN

Peroxisomicines A1 (1) and A2 (2) are cytotoxic hydroxyanthracenones isolated from the fruits of Karwinskia parvifolia. Peroxisomicine A1 exhibits selective cytotoxicity against several tumor cell lines. In the present investigation three minor constituents were obtained from the same fruit extracts: peroxisomicine A3 (3) and isoperoxisomicines A1 (4) and A2 (5). Compounds 3 and 5 are novel and their structures were determined by spectroscopic methods and molecular modeling. Compounds 1-5 were significantly cytotoxic against hepatoma cell lines.


Asunto(s)
Antracenos/aislamiento & purificación , Antineoplásicos Fitogénicos/aislamiento & purificación , Plantas Medicinales/química , Rhamnus/química , Antracenos/química , Antracenos/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Carcinoma Hepatocelular , Cromatografía Líquida de Alta Presión , Dicroismo Circular , Frutas/química , Espectrometría de Masas , México , Conformación Molecular , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Espectrofotometría Infrarroja , Espectrofotometría Ultravioleta , Estereoisomerismo , Relación Estructura-Actividad , Células Tumorales Cultivadas/efectos de los fármacos , Difracción de Rayos X
5.
Cad Saude Publica ; 16(1): 255-60, 2000.
Artículo en Español | MEDLINE | ID: mdl-10738172

RESUMEN

Consumption of fruits from the genus Karwinskia may cause a flaccid paralysis that can be confused with the Guillan-Barré syndrome or poliomyelitis. Paralysis resulting from consumption of such fruit has emerged as a public health problem in certain regions of Mexico. The purpose of this study was to investigate geographical factors associated with this intoxication in the 72 cases reported in Mexico from 1990 to 1994. Location of cases coincides with the distribution of the 11 reported species of Karwinskia in the country. The majority of reported cases were related to the consumption of K. humboldtiana, with a smaller number involving K. mollis, K. parvifolia, K. johnstonii, and K. rzedowskii. Most cases were located in regions with dry climates (79.2%), arid vegetation (41. 7%), and altitudes under 1,000 meters above sea level (54.1%). The study establishes three different risk areas: the Balsas river region in the southwestern central part of the country; the arid northern area; and the arid and dry central area. Cases were from rural communities with low levels of schooling and poor socioeconomic conditions.


Asunto(s)
Parálisis/etiología , Intoxicación por Plantas/epidemiología , Plantas Medicinales , Plantas Tóxicas , Rhamnus/envenenamiento , Niño , Preescolar , Escolaridad , Femenino , Humanos , Lactante , Recién Nacido , Masculino , México/epidemiología , Parálisis/epidemiología , Rhamnus/química , Rhamnus/clasificación , Población Rural , Factores Socioeconómicos
6.
Phytochemistry ; 50(6): 1041-6, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10419282

RESUMEN

Tullidinol, a neurotoxin isolated from fruits and roots of several Karwinskia species, was resolved for the first time into two stereoisomers. This was achieved by means of preparative HPLC from roots of Karwinskia parvifolia. Structural assignments were made on the basis of spectroscopic data, including long range correlations as well as geometry optimization by means of semi-empirical methods.


Asunto(s)
Antracenos/química , Antracenos/farmacología , Plantas Medicinales , Plantas Tóxicas , Piranos/química , Piranos/farmacología , Rhamnus/química , Animales , Antracenos/aislamiento & purificación , Artemia/efectos de los fármacos , Citotoxinas/química , Citotoxinas/aislamiento & purificación , Citotoxinas/farmacología , Neurotoxinas/química , Neurotoxinas/aislamiento & purificación , Neurotoxinas/farmacología , Raíces de Plantas/química , Piranos/aislamiento & purificación , Estereoisomerismo , Pruebas de Toxicidad
7.
Lecta-USF ; 15(1/2): 247-87, jan.-dez. 1997. ilus, tab
Artículo en Portugués | LILACS | ID: lil-280219

RESUMEN

Substâncias isoladas de Ziziphus Miller säo revistas. Nas últimas décadas o estudo de alguns destes compostos tem aumentado devido ao interesse farmacológico e quimiotaxonômico.


Asunto(s)
Farmacología , Rhamnus/química
8.
Toxicon ; 31(10): 1329-32, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8303727

RESUMEN

The teratogenic effect of toxins 544 and 514 from K. humboldtiana upon the mouse embryo was evaluated. One half of the LD50 dose for the mouse was administered at day 8 of gestation. At the end of pregnancy, reproduction and fetal data were recorded. Dams treated with toxin 544, but not with toxin 514, showed a higher incidence of reabsorptions, malformations, as well as lower fetal length compared to the control group.


Asunto(s)
Antracenos/toxicidad , Desarrollo Embrionario y Fetal/efectos de los fármacos , Plantas Medicinales , Plantas Tóxicas , Piranos/toxicidad , Rhamnus/química , Teratógenos/toxicidad , Toxinas Biológicas/toxicidad , Animales , Ratones , Ratones Endogámicos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA