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The composition of the essential oil (EO) obtained by hydro distillation from dry leaves of Heliotropium stenophyllum (Heliotropiaceae) was analyzed using gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). The... more
The composition of the essential oil (EO) obtained by hydro distillation from dry leaves of Heliotropium stenophyllum (Heliotropiaceae) was analyzed using gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). The insecticidal activity of the oil against the house fly Musca domestica was evaluated and the dose necessary to kill 50% of flies (LC 50) in 2 h was determined at 25 ± 1 °C. The essential oil from Heliotropium stenophyllum showed potent insecticidal properties (LC 50 = 1.09 mg/dm 3) in comparison with other essential oils, in which at shorter times, the same bio-assay was used. According to GC and GC/MS analysis, junenol (19.08%); longiborneol (9.34%); (E, Z)-geranyl linalool (6.81%); selina-3,11-dien-6-α-ol (6.70%); α-cedrene epoxide (6.60%); heliofolen-12-al D (6.23%) and β-epi-bisabolol (4.83%) were the principal components of the EO. The Heliotropium stenophyllum essential oil, made up exclusively of sesquiterpenes, showed a composition very different...
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Research Interests: Chemistry, Organic Chemistry, Phytochemistry, Medicine, Antibacterial agents, and 12 moreAntimicrobial, Gram Positive Bacteria, Antibacterial effects of phytochemicals, Molecules, Gram-negative bacteria, Plant extracts, Lipophilicity, Microbial Sensitivity Tests, Structure activity Relationship, Cyclohexane, Benzofuran, and Molecular Structure
... MECHANISMS. ALEJANDRO URZÚA * , ROCÍO SANTANDER, JAVIERECHEVERRÍA, MARCOS C. REZENDE. ... sp. (Himenoptera: Apiadeae) and the butterflyVanessa carye (Lepidoptera: Nymphalinae) also visit the flowers. ...
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Research Interests: Complementary and Alternative Medicine, Traditional Medicine, Plant Biology, Biology, Chile, and 14 moreEthnopharmacology, Flavonoids, Medicine, Antimicrobial activity, Bacteria, Asteraceae, Antimicrobial, Gram Positive Bacteria, Gram-negative bacteria, Plant extracts, Diterpenes, Microbial Sensitivity Tests, Flavonoid, and Pharmacology and pharmaceutical sciences
The diffusion coefficients of five commercial flavonoids in methanol were determined at 25°C utilizing the Taylor–Aris dispersion technique. The results provide insight on solute–solvent interactions, in particular, on subtle differences... more
The diffusion coefficients of five commercial flavonoids in methanol were determined at 25°C utilizing the Taylor–Aris dispersion technique. The results provide insight on solute–solvent interactions, in particular, on subtle differences in hydrogen bonding of the various hydroxyl groups of these compounds with the solvent.
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ABSTRACT Surface compounds were obtained by a methylene chloride extract of fresh flower heads of wild plants of Chrysanthemum coronarium L. in Chile. Three fractions were obtained by column chromatography and analyzed by GC-MS leading to... more
ABSTRACT Surface compounds were obtained by a methylene chloride extract of fresh flower heads of wild plants of Chrysanthemum coronarium L. in Chile. Three fractions were obtained by column chromatography and analyzed by GC-MS leading to the identification of several monoterpenes and sesquiterpene lactones. A hydrocarbon fraction of n-alkanes from C23 to C31 and C33 was also identified. Headspace analysis of the fresh flower heads was carried out. Different proportions of the same mono- and sesquiterpenes were identified in the volatile fraction but not the sesquiterpene lactones. The chemical data was compared with that reported in studies of plants growing in the species' original area of distribution. The proportion of oxygenated terpenoids identified in this report, in relation to those reported in previous communications, is a most relevant characteristic and represents an important difference between the chemistry of individuals of C. coronarium present in Chile and those present in Murcia, Spain and Livorno, Italy. Copyright © 2006 John Wiley & Sons, Ltd.
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Research Interests: Botany, Zoology, Chemical Ecology, Biology, Ecology, and 4 moreBattus, European, Larva, and Aristolochic Acid
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Research Interests: Chemistry, Phytochemistry, Anacardiaceae, Terpenoids, Catechols, and 3 moreUrishiols, Litre, and Allergen
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Two new acylated flavonoids have been isolated from the resinous exudates of Pseudognaphalium robustum and Pseudognaphalium cheirantifolium. Their structures were elucidated by high-resolution spectroscopic methods as... more
Two new acylated flavonoids have been isolated from the resinous exudates of Pseudognaphalium robustum and Pseudognaphalium cheirantifolium. Their structures were elucidated by high-resolution spectroscopic methods as 5,7,8-trihydroxy-3-methoxyflavone 8-O-[(E)-2-methyl-2-butenoate] (1) and 5,7,8-trihydroxy-3, 6-dimethoxyflavone 8-O-[(E)-2-methyl-2-butenoate] (2).
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Research Interests: Complementary and Alternative Medicine, Plant Biology, Biology, Ethnopharmacology, Pharmacognosy, and 9 moreMedicine, Antibacterial activity, Plant extracts, Diterpenes, Haplopappus, Microbial Sensitivity Tests, Structure activity Relationship, Terpenoid, and Pharmacology and pharmaceutical sciences
The antimicrobial properties of the resinous exudate from twigs and leaves of a population of Pseudognaphalium vira vira were re-examined against five Gram positive bacteria. The observed decrease in the antimicrobial activity might... more
The antimicrobial properties of the resinous exudate from twigs and leaves of a population of Pseudognaphalium vira vira were re-examined against five Gram positive bacteria. The observed decrease in the antimicrobial activity might reflect a change in the diterpenoid composition of the exudate. The title compound 2 was isolated in substantial amount, together with ent-16-kauren-19-oic acid (1), and its structure determined by X-ray diffraction analysis.
Research Interests: Complementary and Alternative Medicine, Plant Biology, Biology, Ethnopharmacology, Pharmacognosy, and 15 moreMedicine, Structural Analysis, In Vitro, Gram Positive, Antimicrobial activity, Asteraceae, Gram Positive Bacteria, Hydrogen Bonding, Isolation, Diterpenes, Biological activity, Molecular Structure, Shoot, Plant Leaf, and Pharmacology and pharmaceutical sciences
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The antimicrobial properties of the resinous exudate from twigs and leaves of Eupatorium salvia were tested against five Gram-negative and five Gram-positive bacteria. Comparison of the antimicrobial activities of... more
The antimicrobial properties of the resinous exudate from twigs and leaves of Eupatorium salvia were tested against five Gram-negative and five Gram-positive bacteria. Comparison of the antimicrobial activities of 7-hydroxy-8(17)-labden-15-oic acid (salvic acid) and of its acetate, both ...
Research Interests: Complementary and Alternative Medicine, Plant Biology, Biology, Ethnopharmacology, Medicine, and 12 moreAntimicrobial activity, Tetracycline, Asteraceae, Gram Positive Bacteria, Gram-negative bacteria, Anti-Bacterial Agents, Plant extracts, Diterpenes, Ampicillin, Chloramphenicol, Pharmacology and pharmaceutical sciences, and In Vitro Techniques
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The composition of the essential oil (EO) from Cryptocarya alba obtained by hydro distillation of fresh leaves was analyzed using gas chromatography (GC) and gas chromatography/mass spectrosmetry (GC/MS). The insecticidal effect of the... more
The composition of the essential oil (EO) from Cryptocarya alba obtained by hydro distillation of fresh leaves was analyzed using gas chromatography (GC) and gas chromatography/mass spectrosmetry (GC/MS). The insecticidal effect of the oil on the house fly Musca domestica was evaluated by placing flies in a sealed glass jar containing a piece of EO-treated cotton yarn. The dose necessary to kill 50% of flies (LC50) in 0.5 and 1 h was determined at 26 ± 1 °C. The essential oil from Cryptocarya alba showed significant insecticidal properties [33.56 (7.06-159.50) mg/dm3 (0.5 h) and 15.07 (5.29-42.91) mg/dm3 (1 h)]. According to GC and GC/MS analysis a total of 38 compounds were identified. The composition of the Cryptocarya alba essential oil reported in this study is different to that reported in other publications with 4-terpineol (17.48%) ; 4- (3,3-dimethyl-but-1-ynyl) -4-hydroxy-2,6,6-trimethylcyclohex-2-enone (12.84%); 1,8-cineole (7.90%); p-cymene (7.11%) and sabinene (6.80%), ac...
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... ALEJANDRO URZÚA1,* , RENÉ TORRES1,, LUZ ANDRADE1,, GIULIANO DELLE MONACHE2, ,FRANCO DELLE MONACHE2, JOSÉ LUIS BRIANSÓ3,, FRANCISCO SANCHEZ ... J=14.1 Hz, HA-13), 4.71 (1H, d, J=14.1 Hz, HB-13), 5.25 (2H, s, H-13), 2.90 (1H, dd, J gem... more
... ALEJANDRO URZÚA1,* , RENÉ TORRES1,, LUZ ANDRADE1,, GIULIANO DELLE MONACHE2, ,FRANCO DELLE MONACHE2, JOSÉ LUIS BRIANSÓ3,, FRANCISCO SANCHEZ ... J=14.1 Hz, HA-13), 4.71 (1H, d, J=14.1 Hz, HB-13), 5.25 (2H, s, H-13), 2.90 (1H, dd, J gem =6.9 ...
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ABSTRACT The alkaloid content in the genus Dts-caria of the family Rhamnaceae, has been widely studied. 1-Benzyltetrahydroiso-quinoline and cyclopeptide alkaloids have been identified (1-7). Discaria sewatifolia (Miers) Reiche is endemic... more
ABSTRACT The alkaloid content in the genus Dts-caria of the family Rhamnaceae, has been widely studied. 1-Benzyltetrahydroiso-quinoline and cyclopeptide alkaloids have been identified (1-7). Discaria sewatifolia (Miers) Reiche is endemic of central Chile; it shows a great degree of polymorphism and has been described in no fewer than eight varieties (8). The chemosystematic study of D. ser-ratifolia was initiated with D . serratifolia var. discolor. Only l-benzyltetrahydro-isoquinoline alkaloids were identified in this variety (7). In this paper, the isola-tion and characterization of 1,2-di-methoxy-1 1-hydroxyaporphine, the main alkaloid from D . sewatgolia var. montana twigs, is presented. Preparative tlc of the alkaloid mixture gave a pure compound that crystallized from EtOH, mp 230-231°, [ a ] * ' ~
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From the resinous exudate of Heliotropium huascoense a new compound, rel-(8R,9R)-carrizaloic acid, (1) (3-[rel-(8R,9R-9-hydroxy-9,13,13-trimethyl-12-oxo-10-cyclohexenyl)methyl]-4-methoxybenzoic acid), and three known flavonoids,... more
From the resinous exudate of Heliotropium huascoense a new compound, rel-(8R,9R)-carrizaloic acid, (1) (3-[rel-(8R,9R-9-hydroxy-9,13,13-trimethyl-12-oxo-10-cyclohexenyl)methyl]-4-methoxybenzoic acid), and three known flavonoids, [3-methylgalangin, 3,7-dimethylgalangin, and (-)-alpinone] have been isolated. The structure of 1 was determined by spectral and chemical methods. Several plant defensive properties of 1 (insecticidal and antifungal) have been evaluated.
Research Interests: Chile, Medicinal Plants, Magnetic Resonance Spectroscopy, Flavonoids, Aspergillus, and 15 moreBiological Sciences, Insecticides, Fusarium, Animals, Aphids, Boraginaceae, CHEMICAL SCIENCES, Beetles, Larva, Natural, Hemolymph, Antifungal Agents, Molecular Conformation, Molecular Structure, and Medical and Health Sciences
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The antimicrobiol properties and preliminary chemical information of the resinous exudates from twigs and leaves of nine Haplopappus species from Chile: H. diplopappus; H. anthylloides; H. schumannii; H. cuneifolius; H. velutinus; H.... more
The antimicrobiol properties and preliminary chemical information of the resinous exudates from twigs and leaves of nine Haplopappus species from Chile: H. diplopappus; H. anthylloides; H. schumannii; H. cuneifolius; H. velutinus; H. uncinatus; H. multifolius, H. illinitus and H. foliosus are presented. The results show that those species of genus Haplopappus share similar antimicrobial activities although they differ dramatically in the chemical composition.
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The antibacterial activities of the resinous exudates from Haplopappus uncinatus and H. foliosus are reported. The results provide a justification to the traditional use of the resinous exudates of Haplopappus spp as an antiseptic.
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The antibacterial activity of the methylene chloride and methanol extracts of Chrysantemum coronarium fresh flower heads was investigated. The methylene chloride extract showed discrete antimicrobial activity.
Research Interests: Complementary and Alternative Medicine, Plant Biology, Pharmacognosy, Phytotherapy, In Vitro, and 12 moreHumans, Antimicrobial activity, Flowers, Gram Positive Bacteria, Antibacterial activity, Gram-negative bacteria, Anti-Bacterial Agents, Plant extracts, Fitoterapia, Microbial Sensitivity Tests, Biological activity, and Flor
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... Fate of Ingested Aristolochic Acids in Battus archidamas ALEJANDRO URZUA, RONALD RODRiGUEZ and BRUCE CASSELS* Departamento de Quimica, Facultad de Ciencia, Universidad de Santiago de Chile, Casilla 5659, Santiago-2, Chile;... more
... Fate of Ingested Aristolochic Acids in Battus archidamas ALEJANDRO URZUA, RONALD RODRiGUEZ and BRUCE CASSELS* Departamento de Quimica, Facultad de Ciencia, Universidad de Santiago de Chile, Casilla 5659, Santiago-2, Chile; *Laboratoire de ...