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ANTIOXIDANT PROPERTIES OF LIGNANS AND FERULIC ACID FROM THE RESINOUS EXUDATE OF LARREA NITIDA
TORRES,RENé; URBINA,FRANCISCO; MORALES,CLAUDIA; MODAK,BRENDA; MONACHE,FRANCO DELLE;
Journal of the Chilean Chemical Society , 2003, DOI: 10.4067/S0717-97072003000300012
Abstract: from the resinous exudate of twigs end leaves of larrea nitida, two lignans nor isoguaiacine 1 and meso-nor-dihydroguaiaretic acid 2 and ferulic acid 3 were isolated. the antioxidant activities of resin and pure compounds were assesed by bleaching of the abts derived radical-cation
ANTIOXIDANT PROPERTIES OF LIGNANS AND FERULIC ACID FROM THE RESINOUS EXUDATE OF LARREA NITIDA  [cached]
RENé TORRES,FRANCISCO URBINA,CLAUDIA MORALES,BRENDA MODAK
Journal of the Chilean Chemical Society , 2003,
Abstract: From the resinous exudate of twigs end leaves of Larrea nitida, two lignans nor isoguaiacine 1 and meso-nor-dihydroguaiaretic acid 2 and ferulic acid 3 were isolated. The antioxidant activities of resin and pure compounds were assesed by bleaching of the ABTS derived radical-cation
Study of the Chemical Composition of the Resinous Exudate Isolated from Heliotropium Sclerocarpum and Evaluation of the Antioxidant Properties of the Phenolic Compounds and the Resin  [PDF]
Brenda Modak,Melissa Salina,Jesús Rodilla,René Torres
Molecules , 2009, DOI: 10.3390/molecules14114625
Abstract: Heliotropium sclerocarpum Phil. (Heliotropiaceae) is a resinous bush that grows in the Atacama of northern Chile. The chemical composition of its resinous exudate was analyzed for the first time. One aromatic geranyl derivative: filifolinol (1), one flavanone: naringenin (2) and a new type of 3-oxo-2-arylbenzofuran derivative 3 were isolated and their structures were determined. The antioxidant activity of the phenolic compounds and resin was evaluated using the bleaching of DPPH radical method and expressed as fast reacting equivalents (FRE) and total reacting equivalents (TRE).
IDENTIFICATION OF A NEW AROMATIC GERANYL DERIVATIVE IN THE RESINOUS EXUDATE OF HELIOTROPIUM FILIFOLIUM (BORAGINACEAE)
URZúA,ALEJANDRO; MODAK,BRENDA; TORRES,RENE;
Boletín de la Sociedad Chilena de Química , 2001, DOI: 10.4067/S0366-16442001000200011
Abstract: a new aromatic geranyl derivative was isolated from the resinous exudate of heliotropium filifolium. the structure was elucidated by high-resolution spectroscopic methods as filifolinyl senecionate. the compound has shown antibacterial activity against escherichia coli k-12. after irradiation of a solution of filifolinyl senecionate with uv at 366 nm, the antibacterial activity was enhanced by 100%
IDENTIFICATION OF A NEW AROMATIC GERANYL DERIVATIVE IN THE RESINOUS EXUDATE OF HELIOTROPIUM FILIFOLIUM (BORAGINACEAE)  [cached]
ALEJANDRO URZúA,BRENDA MODAK,RENE TORRES
Boletín de la Sociedad Chilena de Química , 2001,
Abstract: A new aromatic geranyl derivative was isolated from the resinous exudate of Heliotropium filifolium. The structure was elucidated by high-resolution spectroscopic methods as filifolinyl senecionate. The compound has shown antibacterial activity against Escherichia coli K-12. After irradiation of a solution of filifolinyl senecionate with UV at 366 nm, the antibacterial activity was enhanced by 100% Del exudado resinoso de Heliotropium filifolium, se aisló un nuevo derivado aromático geranilado. Este compuesto se identificó por métodos espectrópicos de alta resolución como filifolinil senecionato. El compuesto mostró actividad antibacteriana contra Escherichia coli K-12. Esta actividad se vio incrementada en un 100% después de irradiar una solución de filifolinil senecionato con UV a 366 nm
Chemical Analysis of the Resinous Exudate Isolated from Heliotropium taltalense and Evaluation of the Antioxidant Activity of the Phenolics Components and the Resin in Homogeneous and Heterogeneous Systems  [PDF]
Brenda Modak,Macarena Rojas,René Torres
Molecules , 2009, DOI: 10.3390/molecules14061980
Abstract: H. taltalense (Phil.) Johnst. (Heliotropiaceae) is an endemic species of the northern coast of Chile that produces a resinous exudate that covers its foliar surface and stems. Its chemical composition was analyzed for the first time, and two aromatic geranyl derivatives: filifolinol and filifolinyl senecionate and three flavonoids – naringenin, 3-O-methylgalangin and 7-O-methyleriodictiol – were isolated. The antioxidant activity of the flavonoids and the resinous exudates was carried out by measuring the 1,1-diphenyl-2-picrylhydrazyl (DPPH) bleaching effect in ethanolic solution and in sodium dodecyl sulfate (SDS) micelles. The influence of the reaction medium was analyzed. The initial velocity reactions for the pure compounds and for the extract were higher in SDS media than in ethanolic solution. The velocity of reaction observed was interpreted in terms of the reaction medium environment in the micelle.
ANTIBACTERIAL ACTIVITY OF COMPOUNDS ISOLATED OF THE RESINOUS EXUDATE FROM HELIOTROPIUM SINUATUM ON PHYTOPATHOGENIC BACTERIA
MODAK,BRENDA; TORRES,RENé; WILKENS,MARCELA; URZúA,ALEJANDRO;
Journal of the Chilean Chemical Society , 2004, DOI: 10.4067/S0717-97072004000100001
Abstract: from the resinous exudates of heliotropium sinuatum have been isolated and characterized two compounds, pentaeicosanol 1 and 1-hydroxy-3-doeicosanone 2. those structures and previously isolated pure compounds have been tested in their antibacterial activity on phytopathogenic bacteria. ketone 2 and the flavonoid hesperetine 10 showed antibacterial activity on erwinia carotovora subsp. carotovora, while the flavonoid 3-o-methylgalangine 4 showed activity on clavibacter michiganensis subsp. michiganensis
ANTIBACTERIAL ACTIVITY OF COMPOUNDS ISOLATED OF THE RESINOUS EXUDATE FROM HELIOTROPIUM SINUATUM ON PHYTOPATHOGENIC BACTERIA  [cached]
BRENDA MODAK,RENé TORRES,MARCELA WILKENS,ALEJANDRO URZúA
Journal of the Chilean Chemical Society , 2004,
Abstract: From the resinous exudates of Heliotropium sinuatum have been isolated and characterized two compounds, pentaeicosanol 1 and 1-hydroxy-3-doeicosanone 2. Those structures and previously isolated pure compounds have been tested in their antibacterial activity on phytopathogenic bacteria. Ketone 2 and the flavonoid hesperetine 10 showed antibacterial activity on Erwinia carotovora subsp. carotovora, while the flavonoid 3-O-methylgalangine 4 showed activity on Clavibacter michiganensis subsp. michiganensis
ACTIVIDAD ANTIBACTERIANA DE Diplostephium tolimense Cuatrec. (ASTERACEAE) FRENTE A Staphylococcus aureus ANTIBACTERIAL ACTIVITY OF Diplostephium tolimense Cuatrec. (ASTERACEAE) AGAINST Staphylococcus aures  [cached]
Liliana áVILA,Eduard BAQUERO,Amparo VI?A,Elizabeth MURILLO
Vitae , 2006,
Abstract: Se presenta el estudio de la actividad antibacteriana de la especie vegetal Diplostephium tolimense Cuatrec. (Asteraceae), colectada en el páramo del nevado del Tolima, la cual cuenta con pocos estudios químicos y farmacológicos, al igual que muchas otras especies de este ecosistema. A partir de un extracto etanólico crudo y mediante partición biodirigida se obtiene la fracción más simple de mayor actividad frente a Staphylococcus aureus (ATCC 25923). Paralelamente se realizan análisis fitoquímicos a las porciones de mayor bioactividad obtenidas durante todo el proceso. Se observa que la acción antibacteriana se incrementa al aumentar la simplicidad química del extracto y que terpenos y flavonoides parecen estar relacionados con la acción revelada. Se trata del primer reporte, hasta la fecha conocido, de actividad antibacteriana in vitro para D. tolimense. A study of antibacterial activity of the Diplostephium tolimense Cuatrec (Asteraceae) vegetal species, which was collected in the paramo of Tolima, is presented. This species, as many others of this ecosystem, has had few chemical and pharmacological studies. The simplest fraction with the largest activity against Staphylococcus aureus (ATCC 25923), is obtained starting from a raw ethanol extract and by means of bioassay guided partition. Parallelly, phytochemical analyses to the portions of greater bioactivity, obtained during the whole process, are carried out. It is observed that antibacterial action increases as the chemical simplicity increases and that the presence of terpenes and flavonoids seems to be related with this action. This is the first report, so far well-known, of in vitro antibacterial activity for D. tolimense.
Therapeutic Potential of Polar and Non-Polar Extracts of Cyanthillium cinereum In Vitro  [PDF]
Gunjan Guha,V. Rajkumar,R. Ashok Kumar,Lazar Mathew
Evidence-Based Complementary and Alternative Medicine , 2011, DOI: 10.1093/ecam/nep155
Abstract: Cyanthillium cinereum (Less.) H. Rob. (Asteraceae) has been traditionally known for its medicinal properties, all aspects of which are yet to be exploited. This study was aimed at investigating the therapeutic potential of polar (methanolic and aqueous) and nonpolar (hexane and chloroform) crude extracts of the whole plant. Several parameters including free-radical (DPPH?, ABTS?+, H2O2 and ?OH) scavenging, reducing power, protection of DNA against oxidative damage, cytotoxicity, inhibition of oxidative hemolysis in erythrocytes, total phenolic content and inhibition of lipid peroxidation were examined. All the free-radical generating assay models demonstrated positive scavenging efficiency with differential but considerable magnitudes for the four extracts. However, only the hexane extract showed significant H2O2 scavenging effect. Lipid peroxidation was estimated by thiobarbituric acid-malondialdehyde (MDA) reaction, and a high degree of inhibition was shown by all the extracts. Reducing power of the polar extracts was higher than the non-polar ones. All extracts showed a concentration-dependent increase in phenolic contents. Oxidative damage to erythrocytes was hindered by all extracts in diverse degrees. XTT assay showed that all extracts have mild cytotoxic property. The aqueous extract evidently demonstrated protective effect on pBR322 plasmid DNA against oxidative breakdown. These results suggested the potential of C. cinereum as medicine against free-radical-associated oxidative damage and related degenerative diseases involving metabolic stress, genotoxicity and cytotoxicity. 1. Introduction Atoms or molecules containing one or more unpaired electrons are termed as free radicals which are accountable for tissue degeneration by means of DNA and protein damage and lipid peroxidation. Oxidative stress associated with free radicals is involved in the pathophysiology of aging and various age-related ailments such as cataracts, atherosclerosis, diabetes, Alzheimer's disease, and so forth. The extent of damage caused by free radicals might be mitigated through supplementation with one or more antioxidants [1]. Various compounds with differential antioxidant properties are found in floral resources which are considered to have high potential in the context of therapeutic approaches to encounter and prevent free radical damage. Diverse medicinal plants have been screened and assessed for properties in antagonism to free-radical-induced oxidative stress [2]. Cyanthillium cinereum (Less.) H. Rob. (synonym: Vernonia cinerea (Linn.) Less.), commonly known as
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