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1.
BMC Cardiovasc Disord ; 22(1): 118, 2022 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-35313809

RESUMEN

BACKGROUND: Endothelial progenitor cells (EPCs) are circulating angiogenic cells with endothelial features associated with risk for stroke. We aimed to delve into their functional characteristics. EPCs were isolated and cultured from Ischemic Stroke (IS) patients and predictors of their variance evaluated. METHODS: This is a single-center observational study evaluating 187 consecutively hospitalized patients with IS. EPCs were isolated from blood samples. The number of circulating angiogenic cells (CACs), colony-forming units (CFU-ECs) and the emergence of late outgrowths endothelial cells (LOECs) were counted. We collected clinical variables and measured the stromal cell-derived factor 1 alpha (SDF1α) serum levels. We also examined the relative telomere length and the expression of osteogenic gene markers in CACs. RESULTS: CACs counts and CFU-ECs colony numbers were positively correlated (rho = 0.41, p < 0.001, n = 187). We found significant differences according to whether thrombolytic treatment was performed in the distribution of CFU-ECs (odds ratio (OR) = 2.5; 95% confidence interval (CI) 1.01-6.35; p = 0.042) and CACs (OR = 4.45; 95% IC 1.2-15.5; p = 0.012). The main determinants of CACs variation were the number of risks factors, thrombolysis treatment, arterial hypertension, LOECs occurrence, and the vascular endothelial growth factor expression, whereas CFU-ECs variations depended on hemoglobin content and the relative reduction in the National Institutes of Health Stroke Scale (NIHSS) criteria. The main predictors of LOECs appearance were thrombolysis and length of hospital stay. CONCLUSIONS: Our study supports the relevance of patient risk factors and treatments in the analysis of the functional properties of EPCs.


Asunto(s)
Células Progenitoras Endoteliales , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Células Madre/metabolismo , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/terapia , Factor A de Crecimiento Endotelial Vascular/metabolismo
2.
Molecules ; 26(15)2021 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-34361785

RESUMEN

Even today, weeds continue to be a considerable problem for agriculture. The application of synthetic herbicides produces serious environmental consequences, and crops suffer loss of their activity due to the appearance of new resistant weed biotypes. Our aim is to develop new effective natural herbicides that improve the problem of resistance and do not harm the environment. This work is focused on a bioassay-guided isolation and the characterization of natural products present in Moquiniastrum pulchrum leaves with phytotoxic activity and its preliminary application in weeds. Moquiniastrum pulchrum was selected for two reasons: it is an abundant species in the Cerrado region (the second most important ecosystem in Brazil, after the Amazon)-the explanation behind its being a dominant species is a major focus of interest-and it has traditional employment in folk medicine. Six major compounds were isolated in this plant: one flavone and five diterpenes, two of which are described for the first time in the literature. Four of the six compounds exhibited phytotoxic activity in the bioassays performed. The results confirmed the phytotoxic potential of this plant, which had not been investigated until now.


Asunto(s)
Asteraceae/química , Agentes de Control Biológico/toxicidad , Diterpenos/toxicidad , Flavonas/toxicidad , Herbicidas/toxicidad , Malezas/efectos de los fármacos , Control de Malezas/métodos , Bioensayo , Agentes de Control Biológico/química , Agentes de Control Biológico/aislamiento & purificación , Productos Agrícolas/crecimiento & desarrollo , Diterpenos/química , Diterpenos/aislamiento & purificación , Flavonas/química , Flavonas/aislamiento & purificación , Herbicidas/química , Herbicidas/aislamiento & purificación , Humanos , Estructura Molecular , Extractos Vegetales/química , Hojas de la Planta/química , Malezas/crecimiento & desarrollo
3.
Molecules ; 26(11)2021 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-34199500

RESUMEN

In the search of new alternatives for weed control, spices appear as an option with great potential. They are rich in bioactive natural products and edible, which might minimize toxicity hazard. Marjoram (Origanum majorana L.) is an aromatic herb that has been widely employed as a seasoning herb in Mediterranean countries. Although marjoram boasts a plethora of therapeutic properties (painkiller, antibiotic, treatment for intestinal disorders, etc.), the potential for its extracts for weed control is still to be more thoroughly explored. In order to determine their phytotoxic potential, marjoram leaves were subjected to different bioguided extraction processes, using water, ethyl acetate, acetone or methanol. The most active extract (acetone) was sequentially fractionated to identify its most active compounds. This fractionation led to the isolation and identification of 25 compounds that were classified as monoterpenes, diterpenes or flavonoids. Among them, a new compound named majoradiol and several compounds are described in marjoram for the first time. The phytotoxicity of the major compounds to etiolated wheat coleoptiles was compared against that of the commercial herbicide (Logran®), with similar or higher activity in some cases. These results confirm the extraordinary potential of the extracts from this edible plant to develop safer and more environmentally friendly herbicides.


Asunto(s)
Herbicidas/farmacología , Origanum/química , Fitoquímicos/farmacología , Fraccionamiento Químico , Flavonoides/química , Flavonoides/farmacología , Herbicidas/química , Región Mediterránea , Estructura Molecular , Fitoquímicos/química , Hojas de la Planta/química , Compuestos de Sulfonilurea/farmacología , Terpenos/química , Terpenos/farmacología , Control de Malezas
4.
J Agric Food Chem ; 69(31): 8684-8694, 2021 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-34328733

RESUMEN

Piptocarpha rotundifolia (Less.) Baker stands out as one of the species with the highest frequency, density, and relative dominance in the Cerrado formations. However, no phytochemical studies have been carried out with this species to date. The aim of this study was to evaluate the phytotoxic activity of P. rotundifolia leaves in the search of new environmentally friendly tools for weed control. Thus, a wheat coleoptile and phytotoxic bioassay, using relevant agricultural weeds, was used to identify the most active extracts and fractions. The subsequent purification process allowed the isolation of 11 compounds, the phytotoxicity of which was evaluated in terms of wheat coleoptile elongation and with the most sensitive weeds. Piptocarphin A was found to be the major compound and the most active. To confirm its phytotoxic potential, the effect on Ipomea grandifolia grown in a hydroponic culture and on metaxylem cells was studied. The results obtained in this study demonstrate that the inhibitory activity displayed by P. rotundifolia leaf extract is mainly due to the presence of piptocarphin A. The phytotoxicity shown by P. rotundifolia leaf extract, and the isolated compounds, on weeds could provide new tools for weed control in agricultural fields.


Asunto(s)
Asteraceae , Control de Malezas , Fitoquímicos , Extractos Vegetales/toxicidad , Malezas
5.
Antioxidants (Basel) ; 9(12)2020 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-33287249

RESUMEN

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is causing profound health, economic, and social problems worldwide. Management of personal protective equipment (PPE) and its potential limited availability have created concerns about the increased risks for healthcare professionals at hospitals and nursing homes. Ozone is a powerful oxidant agent. The objectives of this study were to examine the effects of ozone treatment on PPE contaminated with SARS-CoV-2, and to explore whether relative humidity could modify those effects. METHODS: PPE contaminated by heat-inactivated SARS-CoV-2 were treated with different ozone concentrations, exposure times, and relative humidity conditions. SARS-CoV-2 gene amplification was assessed by real-time polymerase chain reaction. RESULTS: There was no amplification of SARS-CoV-2 in PPE after the following ozone exposures: 30 s at 10,000 ppm (20 g/m3), 5 min at 4000 ppm, and 10 min at 2000 ppm. At lower ozone concentrations, 4-12 ppm (0.008-0.024 g/m3), the effects were highly dependent on the relative humidity conditions. CONCLUSIONS: Oxidative stress induced by ozone exposure eliminated heat-inactivated SARS-CoV-2 in different PPE components under appropriate exposure times, ozone concentrations, and relative humidity conditions. These findings could have implications in decreasing the risk of contamination associated with personal protective equipment management and in increasing its availability. Further research in the original SARS-CoV-2 strain is guaranteed.

6.
J Agric Food Chem ; 68(17): 4851-4864, 2020 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-32259440

RESUMEN

Herbicides are a key element in agriculture but they do cause environmental problems and natural alternatives are being sought. In this context, invasive plants could provide an as yet unexplored source for the development of future herbicides. Urochloa humidicola has great invasive potential in Brazilian environments as it hampers the establishment of other plants. The phytotoxicity of U. humidicola root extracts has been evaluated, and the major components have been identified. The phytotoxicity of the extract was assessed in the wheat coleoptile assay on seeds of troublesome weeds and on Anadenanthera colubrina, a tree species used in ecological restoration programs. The ethyl acetate extract showed the highest activity, and the most affected weeds were E. crus-galli, M. maximus, and A. viridis with the latter weed more affected by the extract than by the herbicide Logran. Microscopic ultrastructural analysis of A. colubrina roots indicated possible signals of cell death. Seven compounds were identified in the ethyl acetate extract of which one diterpene and four saponins are new. Six of these compounds were tested in the wheat coleoptile bioassay. The most active were diterpene 1 and saponins 2, 3, and 6. The phytotoxic activity of U. humidicola explains the issues observed in ecological restoration with A. colubrina in the presence of Urochloa species, and its effect on weeds reinforces its potential use in agriculture.


Asunto(s)
Brachiaria/química , Herbicidas/farmacología , Extractos Vegetales/farmacología , Raíces de Plantas/química , Bioensayo , Brasil , Herbicidas/química , Estructura Molecular , Extractos Vegetales/química , Malezas/efectos de los fármacos , Poaceae/efectos de los fármacos
7.
Aquat Toxicol ; 211: 81-91, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30954847

RESUMEN

The excessive proliferation of toxin producing cyanobacteria constitutes a significant health risk to the environment and humans. This is due to the contamination of potable water and accumulation of cyanotoxins in plant and animal tissues. As a means of controlling bloom forming cyanobacteria, secondary metabolites with pro-oxidative activities from plants are used to treat water bodies contaminated with cyanobacterial blooms and their associated toxins. The objective of the present study was to evaluate the mechanism of action of extract, fractions and isolated flavonoids of Tridax procumbens L. on Microcystis aeruginosa (Kützing) Kützing. by monitoring changes in growth, oxidative stress, antioxidant response, and cyanatoxin microcystins (MCs) production. The extract, fraction 3 and the isolated flavonoids significantly reduced the cell density of the cyanobacterium. Furthermore, the extract and fraction 3 increased the production of reactive oxygen species, induced lipid peroxidation, and altered antioxidant enzyme activities of M. aeruginosa. The total MCs content of the cyanobacterium was negatively affected by the presence of the extract, fractions and isolated flavonoids. The present study show that T. procumbens has secondary metabolites that are capable of interfering with the physiology and microcystins production of M. aeruginosa. These characteristics are promising for the control of this noxious cyanobacterium in aquatic ecosystems.


Asunto(s)
Asteraceae/química , Flavonoides/farmacología , Microcistinas/análisis , Microcystis/efectos de los fármacos , Extractos Vegetales/química , Contaminantes Químicos del Agua/análisis , Animales , Antioxidantes/metabolismo , Relación Dosis-Respuesta a Droga , Flavonoides/aislamiento & purificación , Peroxidación de Lípido/efectos de los fármacos , Microcystis/crecimiento & desarrollo , Microcystis/metabolismo , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo
8.
Am Surg ; 84(9): 1489-1492, 2018 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-30268182

RESUMEN

Opening a new pediatric trauma center (PTC) is a sizable undertaking. A pediatric trauma team of specialists must be assembled, appropriate equipment and facilities prepared, and staff educated. Our PTC opened in May 2016, before that we had a pediatric emergency center. This study aimed to evaluate initial performance, and compare practices and outcomes before and after becoming a PTC. A review of prospectively collected data using our hospital's Trauma Registry. We compared patient profiles and outcomes 4.5 years before and one year after our hospital became a PTC. Demographic variables, outcomes, Injury Severity Score, and surgical interventions were compared. Chi Squared analysis and t test were used, with significance defined as P < 0.05. For the 4.5 years before opening the PTC, we averaged 96 pediatric trauma admissions annually. After opening, we had 289 admissions in one year, (146% increase, P < 0.05). Mean Injury Severity Score significantly increased from 3.7 to 5.3 postopening (P < 0.05), as did the number of surgical interventions from 19 to 88 (P < 0.001), but mortality did not change (no deaths). Transfers out of the hospital significantly decreased (3.8%) compared with preopening (10.4%, P = 0.03), whereas transfers into the hospital significantly increased, (38 compared with 62, P = 0.003). When mode of transportation was compared, pre- and postopening of the PTC, patient transport by air increased from 3 per cent to 35 per cent (P < 0.001). Transitioning from a pediatric emergency center to a PTC resulted in increased patient volumes, presentation of more severely injured patients, and increased surgical interventions, without a change in mortality.


Asunto(s)
Administración Hospitalaria , Centros Traumatológicos/organización & administración , Heridas y Lesiones/epidemiología , Niño , Femenino , Humanos , Puntaje de Gravedad del Traumatismo , Masculino , Evaluación de Resultado en la Atención de Salud , Transferencia de Pacientes , Estudios Retrospectivos , Heridas y Lesiones/diagnóstico , Heridas y Lesiones/terapia
9.
Phytochemistry ; 141: 162-170, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28633108

RESUMEN

Isohexenylnaphthazarins are commonly found in the root periderm of several Boraginaceous plants and are known for their broad range of biological activities. The work described herein concerns the biological activity of compounds from the roots of Echium plantagineum L. and Echium gaditanum Boiss (Boraginaceae) collected from field sites in southern Spain and Australia. Bioactivity was assessed using etiolated wheat coleoptile bioassay and in vitro growth inhibitory activity in HeLa and IGROV-1 cells. The quantification of four isohexenylnaphthazarins (shikonin/alkannin, deoxyshikonin/deoxyalkannin, acetylshikonin/acetylalkannin and dimethylacrylshikonin/dimethylacrylalkannin) was performed by LC-MS/MS using juglone as internal standard. Correlation coefficient values for the activities and concentrations of these four analytes were in the linear range and were greater than 0.99. Acetylshikonin/acetylalkannin and dimethylacrylshikonin/dimethylacrylalkannin were present in the highest concentrations in extracts of both species. The results reveal that greatest overall inhibition was observed in both bioassays with E. gaditanum extracts. Strong correlations between time of collection, sampling location and bioactivity were identified.


Asunto(s)
Echium/química , Naftoquinonas/química , Raíces de Plantas/química , Australia , Línea Celular Tumoral , Supervivencia Celular , Echium/clasificación , Humanos , Naftoquinonas/aislamiento & purificación , Extractos Vegetales/química , España , Triticum/efectos de los fármacos
10.
J Agric Food Chem ; 65(25): 5161-5172, 2017 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-28605187

RESUMEN

Farmers of the Franca region in Brazil observed that Bidens sulphurea was able to eliminate the Panicum maximum weed, which infected coffee plantations, without affecting the crop. In an effort to determine if the inhibitory effects observed were due to the presence of phytotoxic compounds from leaves and roots, a biodirected isolation and spectroscopic characterization has been carried out. The leaf dichloromethane and root acetone extracts were the most active, and the former appeared to be more phytotoxic to the target species, including four weeds. A total of 26 compounds were isolated from leaves and roots, and four of them are described here for the first time. The major compounds in the leaf extract are the sesquiterpene lactones costunolide, reynosin, and santamarine, and these showed marked inhibition. Amaranthus viridis and Panicum maximum were the most sensitive species of the weeds tested. These three phytotoxic lactones were also evaluated on A. viridis and P. maximum under hydroponic conditions. A. viridis was the most affected species with the three lactones, and santamarine was the most phytotoxic compound on both. This is the first time that the phytotoxicity of sesquiterpene lactones has been evaluated on hydroponic culture. The work described here is a preliminary approach for the use of B. sulphurea for weed control in agriculture, both as a cover crop and by use of its components as natural herbicide leads.


Asunto(s)
Bidens/química , Herbicidas/toxicidad , Extractos Vegetales/toxicidad , Malezas/efectos de los fármacos , Amaranthus/efectos de los fármacos , Asteraceae/efectos de los fármacos , Brasil , Herbicidas/química , Herbicidas/aislamiento & purificación , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/química , Raíces de Plantas/química , Control de Malezas
11.
Inj Epidemiol ; 4(1): 12, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28393320

RESUMEN

BACKGROUND: The state of Florida continues to report significant gender, ethnic and racial disparities in trauma incidence, access to care and outcomes in the adult population. Our objective was to assess pediatric injury profiles and ethnic/racial disparities of specific injuries in a Regional Trauma Center (TC) in South Florida. METHODS: Retrospective data from November 2011 to December 2015 were obtained from the Level 2 TC registry for children ≤21 years old. Demographic, injury pattern, geographic area, injury scores and treatment data were analyzed. RESULTS: One thousand six hundred ten patients, ages 0-21 years were cared for at the TC from 2011 to 2015.73% were males. Mean age = 15.7 years. Mortality was 2.3%. Using zip code data and using geographic mapping, we identified two main clusters where injuries were occurring. A multinomial regression analysis demonstrated that Hispanics had higher risks of falls (RR 10.4, 95% CI 2.7-29), motorcycle accidents (RR 3.7, 95% CI 1.7-8.2) and motor vehicle accidents (RR 6.4, 95% CI 3.6-11.4). Black/African American children had higher risks of gunshot wounds and resultant mortality (p < 0.01). CONCLUSION: There were racial, ethnic and gender disparities in the patterns of injury and outcomes among the youth attended at our TC. Geographic mapping allowed us the identification of the zones in South Florida where injuries were occurring. Understanding the differences and using geographic mapping to identify regions of higher prevalence will complement planning for prevention programs.

12.
Chem Biodivers ; 13(8): 1058-67, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27482860

RESUMEN

Despite the increase in recent decades in herbicide research on the potential of native plants, current knowledge is considered to be low. Very few studies have been carried out on the chemical profile or the biological activity of the Brazilian savanna (Cerrado) species. In the study reported here, the allelopathic activity of AcOEt and MeOH extracts of leaves, stems, and roots from Ocotea pulchella Nees was evaluated. The extracts were assayed on etiolated wheat coleoptiles. The AcOEt leaf extract was the most active and this was tested on standard target species (STS). Lycopersicon esculentum and Lactuca sativa were the most sensitive species in this test. A total of eleven compounds have been isolated and characterized. Compounds 1, 2, 4, and 6 have not been identified previously from O. pulchella and ocoteol (9) is reported for the first time in the literature. Eight compounds were tested on wheat coleoptile growth, and spathulenol, benzyl salicylate, and benzyl benzoate showed the highest activities. These compounds showed inhibitory activity on L. esculentum. The values obtained correspond to the activity exhibited by the extract and these compounds may therefore be responsible for the allelopathic activity shown by O. pulchella.


Asunto(s)
Ocotea/química , Extractos Vegetales/farmacología , Raíces de Plantas/química , Tallos de la Planta/química , Solanum lycopersicum/efectos de los fármacos , Triticum/efectos de los fármacos , Brasil , Cotiledón/efectos de los fármacos , Solanum lycopersicum/crecimiento & desarrollo , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/química , Triticum/crecimiento & desarrollo
13.
J Agric Food Chem ; 64(33): 6416-24, 2016 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-27487046

RESUMEN

The work described herein is a continuation of a previous study centered on the bioprospect of cardoon (Cynara cardunculus) leaf extracts through the isolation of secondary metabolites with phytotoxic activity. Chromatographic fractionations of the ethyl acetate extract and spectroscopic analysis showed that the majority of the components were sesquiterpene lactones. Of these compounds, aguerin B, grosheimin, and cynaropicrin were very active on etiolated wheat coleoptile, standard target species, and weed growth. The joint action of binary mixtures of these three active sesquiterpene lactones and one nonactive compound (11,13-dihydroxy-8-desoxygrosheimin) was studied. The activities of fixed-ratio mixtures were assessed on wheat coleoptile. The results can be interpreted with respect to a reference model by considering dose-response analyses and isobolograms with linear regression analyses. A total of 17 binary mixtures at different levels of inhibition (ED25, ED50, and ED75) were studied, and predominantly they responded additively (25). Deviations from additivity included seven synergistic responses and two antagonistic responses. The joint action of major sesquiterpene lactones isolated from C. cardunculus can explain the activities observed in extracts and fractions. The results reported here reiterate the utility of the wheat coleoptile bioassay as a quick tool to detect potential synergistic effects in binary mixtures.


Asunto(s)
Cynara/química , Lactonas/química , Extractos Vegetales , Sesquiterpenos/química , Cotiledón/efectos de los fármacos , Estructura Molecular , Extractos Vegetales/química , Hojas de la Planta/química , Triticum/efectos de los fármacos
14.
Molecules ; 20(11): 20079-106, 2015 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-26561798

RESUMEN

The citrus by-products released from citrus processing plants may contain high levels of potentially bioactive compounds such as flavonoids, which are a widely distributed group of polyphenolic compounds with health-related properties based on their antioxidant activity. In the study reported here, the potential bioactivities and antioxidant activities of extracts, fractions and compounds from citrus by-products were evaluated along with the chemical interactions of binary mixtures of compounds and complex mixtures. The bioactivities and interactions were evaluated in wheat coleoptile bioassays and the antioxidant activity was evaluated by the al DPPH (2,2-diphenyl-1-picrylhdrazyl radical) radical scavenging assay. The extracts, fractions and most of the isolated compounds (mainly polymethoxyflavones) showed high activity in the wheat coleoptile bioassay. However, the antioxidant activity was not consistently high, except in the acetone extract fractions. Moreover, a study of the interactions with binary mixtures of polymethoxyflavones showed the occurrence of synergistic effects. The complex mixtures of fractions composed mainly of polymethoxyflavones caused a synergistic effect when it was added to a bioactive compound such as anethole. The results reported here highlight a new application for the wheat coleoptile bioassay as a quick tool to detect potential synergistic effects in compounds or mixtures.


Asunto(s)
Citrus/química , Flavonas/química , Flavonas/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Interacciones Farmacológicas , Sinergismo Farmacológico , Flavonas/aislamiento & purificación , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/aislamiento & purificación , Depuradores de Radicales Libres/farmacología , Estructura Molecular , Extractos Vegetales/aislamiento & purificación
15.
Org Lett ; 17(19): 4730-3, 2015 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-26368065

RESUMEN

Four novel compounds (1-4) with an unprecedented skeleton that combines a sesquiterpene lactone and a kaurane diterpene acid were isolated from Helianthus annuus L. var. Arianna extract, which was obtained under supercritical conditions. The structures of 1-4 were elucidated by NMR and MS analyses. The biosynthetic routes involve sesquiterpene lactones and kauranic acid, both of which were previously isolated from this species.


Asunto(s)
Diterpenos/aislamiento & purificación , Helianthus/química , Lactonas/aislamiento & purificación , Sesquiterpenos/aislamiento & purificación , Líquidos Corporales , Diterpenos/química , Lactonas/química , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Sesquiterpenos/química
16.
J Agric Food Chem ; 63(28): 6410-21, 2015 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-26151222

RESUMEN

The work described herein is a continuation of our initial studies on the supercritical fluid extraction (SFE) with CO2 of bioactive substances from Helianthus annuus L. var. Arianna. The selected SFE extract showed high activity in the wheat coleoptile bioassay, in Petri dish phytotoxicity bioassays, and in the hydroponic culture of tomato seeds. Chromatographic fractionations of the extracts and a spectroscopic analysis of the isolated compounds showed 52 substances belonging to 10 different chemical classes, which were mainly sesquiterpene lactones, diterpenes, and flavonoids. Heliannuol M (31), helivypolides K and L (36, 37), and helieudesmanolide B (38) are described for the first time in the literature. Metabolites have been tested in the etiolated wheat coleoptile bioassay with good results in a noteworthy effect on germination. The most active compounds were also tested on tomato seeds, heliannuol A (30) and leptocarpin (45) being the most active, with values similar to those of the commercial herbicide.


Asunto(s)
Cromatografía con Fluido Supercrítico , Helianthus/química , Herbicidas/aislamiento & purificación , Extractos Vegetales/química , Hojas de la Planta/química , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Diterpenos/análisis , Diterpenos/química , Diterpenos/farmacología , Flavonoides/análisis , Flavonoides/química , Flavonoides/farmacología , Germinación/efectos de los fármacos , Herbicidas/química , Herbicidas/farmacología , Lactonas/análisis , Lactonas/química , Lactonas/farmacología , Solanum lycopersicum/efectos de los fármacos , Estructura Molecular , Semillas/crecimiento & desarrollo , Sesquiterpenos/análisis , Sesquiterpenos/química , Sesquiterpenos/farmacología
17.
J Nat Prod ; 78(5): 1083-92, 2015 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-25879678

RESUMEN

Tithonia diversifolia (Mexican sunflower) is a dominant plant of the Asteraceae family, which suggests it produces allelochemicals that interfere with the development of surrounding plants. The study described herein was conducted to identify the compounds that have phytotoxic activity in T. diversifolia extracts. Ethyl acetate extracts of the leaves, stems, and roots showed significant inhibition of wheat coleoptile growth, and the leaf extract had similar inhibitory effects to a commercial herbicide. Fourteen compounds, 12 of which were sesquiterpene lactones, have been isolated. Two sesquiterpene lactones are reported for the first time and were isolated as an inseparable mixture of 8ß-O-(2-methylbutyroyl)tirotundin (4) and 8ß-O-(isovaleroyl)tirotundin (5). Their structures were determined by spectroscopic analysis, including NMR techniques and mass spectrometry. The sesquiterpene lactones 1ß-methoxydiversifolin (6), tagitinin A (7), and tagitinin C (8) were the major products identified. These compounds were active on etiolated wheat coleoptiles, seed germination, and the growth of STS and weeds. The phytotoxic activity shown by these sesquiterpene lactones indicates that they are the compounds responsible for the activity exhibited by the initial extracts.


Asunto(s)
Asteraceae/química , Lactonas/aislamiento & purificación , Lactonas/farmacología , Extractos Vegetales/farmacología , Sesquiterpenos/aislamiento & purificación , Sesquiterpenos/farmacología , Brasil , Lactonas/química , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Hojas de la Planta/química , Raíces de Plantas/química , Tallos de la Planta/química , Malezas/efectos de los fármacos , Sesquiterpenos/química
18.
Bioorg Med Chem ; 20(22): 6662-8, 2012 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-23063518

RESUMEN

Bioactive natural products are a potential source of new pharmaceuticals since they offer new modes of action and more specific activities. The use of derivatization also enables the optimal structure for their biological activity to be determined. In this study several epoxycurcuphenol derivatives were synthesized. The substitution pattern on the aromatic and oxirane rings was varied along with that at the benzylic position and the length of the side chain was altered. These changes were made in order to gain a deeper understanding of the structural requirements for activity. The biological activities of these compounds were evaluated on the human leukemia cell line Jurkat using an antiproliferative assay. The activity results and structural requirements are discussed.


Asunto(s)
Sesquiterpenos/química , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Proliferación Celular/efectos de los fármacos , Óxido de Etileno/química , Humanos , Células Jurkat , Leucemia/patología , Sesquiterpenos/síntesis química , Sesquiterpenos/toxicidad , Estereoisomerismo , Relación Estructura-Actividad
19.
J Sep Sci ; 32(9): 1445-53, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19330786

RESUMEN

The kinetics of the supercritical fluid extraction of bioactive compounds from sunflower using CO(2) as solvent were studied in order to establish an efficient method for this extraction. The influence of time of extraction at different solvent flow rates was investigated. The extraction pressure and temperature were optimized in previous studies and these values used were 400 bar and 50 degrees C. The extraction yields and the bioactivity levels of the extracts were also analysed. The results indicate that the most appropriate extraction time is between 120 and 180 min depending on the solvent flow and the pretreatment of the sample. The dried sample extracted at 40 g/min, the congealed sample extracted at the same flow and 180 min, and the dried sample extracted at 25 g/min for 120 min showed the best activity profiles. The extractions were carried out in a pilot plant with an extraction vessel with a capacity of 2 L.


Asunto(s)
Helianthus/química , Reguladores del Crecimiento de las Plantas/aislamiento & purificación , Hojas de la Planta/química , Algoritmos , Cromatografía con Fluido Supercrítico , Análisis por Conglomerados , Cotiledón/efectos de los fármacos , Cotiledón/crecimiento & desarrollo , Cinética , Tamaño de la Partícula , Reguladores del Crecimiento de las Plantas/farmacología , Presión , Reología , Solventes/química , Gravedad Específica , Temperatura , Factores de Tiempo , Viscosidad
20.
J Chem Ecol ; 34(1): 65-9, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18071822

RESUMEN

A new ent-kaurane glucoside, named helikauranoside A (4), was isolated from the aerial parts of Helianthus annuus L. together with three known ent-kaurane-type diterpenoids: (-)-kaur-16-en-19-oic acid (1), grandifloric acid (2), and paniculoside IV (3). The structure of 4 was determined by using a combination of 1D (1H-NMR and 13C-NMR) and 2D (COSY, HSQC, and HMBC) NMR techniques. Bioactivity spectra of isolated compounds were tested by using the etiolated wheat coleoptile bioassay in aqueous solutions at concentrations ranging from 10(-3) to 10(-6)M. Helikauranoside A (4) was the most active (-84%, 10(-3)M; -56%, 10(-4)M). These results suggest that this new compound may be involved in defense mechanisms of H. annuus.


Asunto(s)
Diterpenos/análisis , Diterpenos/farmacología , Helianthus/química , Triticum/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Feromonas/análisis , Feromonas/farmacología , Extractos Vegetales/análisis , Extractos Vegetales/farmacología , Hojas de la Planta/química , Triticum/crecimiento & desarrollo
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