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Alejandro Urzua - One of the best experts on this subject based on the ideXlab platform.
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Antifungal activity against Botrytis cinerea of labdane-type diterpenoids isolated from the resinous exudate of Haplopappus velutinus Remy (Asteraceae)
2018Co-Authors: Javier Echeverria, Marcia González-teuber, Alejandro UrzuaAbstract:Two labdane diterpenoids were isolated, from the resinous exudate of Haplopappus velutinus Remy (Asteraceae); the main compound was identified as 7,13-(E)-labdadien-15,18-dioic-acid-18-methyl ester (1) and the minor compound identified as 7-labden-15,18-dioic-acid-18-methyl ester (2). Their structures were obtained using FTIR, MS, HRMS and NMR data: 1D NMR (1H, 13C and DEPT-135), 2D homonuclear NMR (COSY and NOESY) and heteronuclear NMR (HSQC and HMBC). The trans stereochemistry of the decalin moiety of compounds 1 and 2 was established through NOESY experiments of the reduction product of 1; 7-labden-15,18-diol (1a). Diterpenoids 1 and 1a are described for the first time and showed antifungal activity, inhibiting approximately 40% mycelial growth of Botrytis cinerea.
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lipophilicity and antibacterial activity of flavonols antibacterial activity of resinous exudates of Haplopappus litoralis h chrysantemifolius and h scrobiculatus
Latin American and Caribbean Bulletin of Medicinal and Aromatic Plants, 2012Co-Authors: Alejandro Urzua, Javier Echeverria, Javier Espinoza, Marcela WilkensAbstract:La actividad antibacteriana de los exudados resinosos de Haplopappus litoralis, H. chrysantemifolius y H. scrobiculatus de la Zona Central de Chile fueron evaluadas frente a bacterias Gram-negativas y Gram-positivas, y resultaron activos frente a estas ultimas. Los resultados mostraron que la actividad antibacteriana de los exudados resinosos es independiente de los flavonoles aisladas de cada extracto que no mostraron actividad antibacteriana. La lipofilia estimada de los flavonoles aislados de los exudados resinosos de Haplopappus se comparo con la lipofilia de conocidos flavonoles antibacterianos. Este analisis mostro que la lipofilia es una variable importante para predecir la actividad antibacteriana de los flavonoles
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insecticide properties of the essential oils from Haplopappus foliosus and bahia ambrosoides against the house fly musca domestica l
Journal of The Chilean Chemical Society, 2010Co-Authors: Alejandro Urzua, Sara M Palacios, Rocio Santander, Javier Echeverria, Nancy J Cabezas, Yanina RossiAbstract:The compositions of the essential oils (EO’s) obtained by hydro distillation from fresh leaves of Haplopappus foliosus and bahia ambrosoides was analyzed by gas chromatography/mass spectroscopy (GC/MS). The insecticidal activity of each oil against the house fly Musca domestica was evaluated by placing flies in a glass jar with a screw cap that held a piece of EO-treated cotton yarn. The dose necessary to kill 50% of flies (LC 50 ) in 1 h was determined at 26±1°C. The essential oil from Haplopappus foliosus was the most potent insecticide (LC 50 = 4.43 mg/dm 3), wile the EO from bahia ambrosoides shows only moderated insecticide activity (LC 50 = 19.27 mg/dm3). According to GC and GC/MS analysis, limonene (28,00%); epi-bicyclosesquiphellandrene (9,84%); bornyl acetate (7,74%); 4-terpineol (6,36%); p-cymene (6,00%); agarospirol (5,53%); α-muurolene (4,34%); δ-cadinene (3,98%) and caryophyllene (3,97%) were the principal components of Haplopappus foliosus EO and limonene (28,16%); α-pinene (11,12%); germacrene D (8,81%); sabinene (5,93%); α-thujene (3,48%); γ-curcumene (3,45%) y α-bergamotene (3,36%) were the principal components of bahia ambrosoides EO. The EO from Haplopappus foliosus seem promising as a natural insecticide against houseflies and the difference with the activity of the EO of bahia ambrosoides can be ascribed to the content of oxygenated monoterpenoids and sesquiterpenoids.
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a new antibacterial clerodane diterpenoid from the resinous exudate of Haplopappus uncinatus
Journal of Ethnopharmacology, 2006Co-Authors: Alejandro Urzua, Leonora Mendoza, Francisco Jara, Marcela Wilkens, Emilia Tojo, Marcos Caroli RezendeAbstract:The antibacterial activity of Haplopappus uncinatus is attributed to a new clerodane diterpenoid, 18-acetoxy-cis-cleroda-3-en-15-oic acid (10H, 16 19 ,1 7 ,2 0 form) (1), isolated as a major component from the resinous exudates of its twigs and leaves, together with the inactive 3,5-dihydroxy-6,7,3 � ,4 � -tetramethoxyflavone, n-alkanes and a few sesquiterpenoids. © 2005 Elsevier Ireland Ltd. All rights reserved.
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secondary metabolites in the epicuticle of Haplopappus foliosus dc asteraceae
Journal of The Chilean Chemical Society, 2004Co-Authors: Alejandro UrzuaAbstract:From the CH2Cl2 extract of the surface of Haplopappus foliosus, monoterpenes, sesquiterpenes, flavonoids, coumarins, phenyl propanoids, n-alkanes and different miscellaneous compounds were identified. The complexity of the chemistry in terms of number of families and compounds makes attractive the use of this specie as a model to study variations in the cuticle chemistry, triggered by different ecological pressures. Keywords: Haplopappus foliosus; Monoterpenes; Sesquiterpenes; Flavonoids; Coumarins; phenyl propanoids, n-Alkanes; miscellaneous compounds
Leonora Mendoza - One of the best experts on this subject based on the ideXlab platform.
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a new antibacterial clerodane diterpenoid from the resinous exudate of Haplopappus uncinatus
Journal of Ethnopharmacology, 2006Co-Authors: Alejandro Urzua, Leonora Mendoza, Francisco Jara, Marcela Wilkens, Emilia Tojo, Marcos Caroli RezendeAbstract:The antibacterial activity of Haplopappus uncinatus is attributed to a new clerodane diterpenoid, 18-acetoxy-cis-cleroda-3-en-15-oic acid (10H, 16 19 ,1 7 ,2 0 form) (1), isolated as a major component from the resinous exudates of its twigs and leaves, together with the inactive 3,5-dihydroxy-6,7,3 � ,4 � -tetramethoxyflavone, n-alkanes and a few sesquiterpenoids. © 2005 Elsevier Ireland Ltd. All rights reserved.
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antibacterial new clerodane diterpenes from the surface of Haplopappus foliosus
Planta Medica, 2003Co-Authors: Alejandro Urzua, Rene Torres, Leonora Mendoza, Franco Delle MonacheAbstract:A biologically monitored fractionation of the resinous exudate extract of Haplopappus foliosus DC. is reported. Purification of the two active fractions yielded 2-alpha-hydroxy- cis-cleroda-3,13(Z),8(17)-trien-15-oic acid (1) and 2-alpha-acetoxy- cis-cleroda-3,13(Z),8(17)-trien-15-oic acid (2), two new clerodane diterpenes.
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antibacterial activity of the resinous exudates from Haplopappus uncinatus and Haplopappus foliosus
Fitoterapia, 2001Co-Authors: Alejandro Urzua, Leonora MendozaAbstract: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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clerodane diterpenes from Haplopappus deserticola
Phytochemistry, 1999Co-Authors: Emilia Tojo, Alejandro Urzua, M E Rial, Leonora MendozaAbstract:From the resinous exudate of Haplopappus deserticola a new clerodane diterpene named deserticolic acid (1), the known 18-acetoxy-cis-cleroda-3,13E-dien-15-oic acid (2) and four flavonoids were isolated. The structure of 1 was elucidated as 19-hydroxy-cis-cleroda-3,13E-dien-15-oic acid (ent-5α form) by spectroscopic methods.
Rene Torres - One of the best experts on this subject based on the ideXlab platform.
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chemistry and bioactivity of Haplopappus remyanus bailahuen a chilean medicinal plant
Journal of the Brazilian Chemical Society, 2011Co-Authors: Francesca Faini, Rene Torres, Cecilia Labbe, Jesus M Rodilla, Carla Delporte, Fabian JanaAbstract:Chromatography on the resinous extract of aerial parts of Haplopappus remyanus led to the isolation of 18-acetoxy-labda-7,13E-dien-15-oic acid along with the monoterpene derivatives 9-hydroxy-α-terpineol, 9-benzoyloxy-α-terpineol,7-hydroxy-9-benzoyloxy-α-terpineoland 9-benzoyloxy-(1-formyl)-α-terpineol. Structures for the new compounds are proposed on spectroscopic evidence. The presence of quercetin and five other known flavonoids identified in this study could account for the reported high antioxidant activity and the moderate topic anti-inflammatory effect on induced ear oedema. MTT assay with CCRF-CEM tumor cells showed 50% of the cytotoxic activity displayed by doxorubicin under the same conditions. Quantitative differences in chemical composition were detected in comparison with previous studies of the species that could be attributed to environmental factors.
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new phenolic esters from the resinous exudate of Haplopappus taeda
Fitoterapia, 2007Co-Authors: Francesca Faini, Rene Torres, Cecilia Labbe, Jesus M Rodilla, Lucia Silva, Franco Delle MonacheAbstract:Two new phenolic esters 9-trans-p-coumaroyloxy-alpha-terpineol (1) and 7-trans-p-coumaroyloxy-taedol (2), both endowed with free radical scavenger activity and cleroda-3,13 (E)-dien-15,18-diol (3) for which a cis stereochemistry at the decalin junction was found, were isolated from the resinous exudate from Haplopappus taeda upper parts.
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phytochemical communication new phenolic esters from the resinous exudate of Haplopappus taeda
2007Co-Authors: Francesca Faini, Rene Torres, Cecilia Labbe, Jesus M Rodilla, Lucia Silva, Franco Delle MonacheAbstract:Two new phenolic esters 9-trans-p-coumaroyloxy-α-terpineol (1) and 7-trans-p-coumaroyloxy-taedol (2), both endowed with free radical scavenger activity and cleroda-3,13 (E)-dien-15,18-diol (3) for which a cis stereochemistry at the decalin junction was found, were isolated from the resinous exudate from Haplopappus taeda upper parts. © 2007 Elsevier B.V. All rights reserved.
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antioxidant activity of coumarins and flavonols from the resinous exudate of Haplopappus multifolius
Phytochemistry, 2006Co-Authors: Rene Torres, Francesca Faini, Brenda Modak, Francisco Urbina, Cecilia Labbe, Juan GuerreroAbstract:The antioxidant activity of eight coumarins and two flavonols isolated from Haplopappus multifolius was studied with the DPPH radical method. Results show that a high concentration of phenolic coumarins and the presence of quercetin and rhamnetin in the exudates could account for the protection of the plant against oxidative stress. Structures for the coumarins 6-hydroxy-7-[(E,E)-3',7'-dimethyl-2',4',7'-octatrienyloxy] coumarin and 7-[(E)-3'-methyl-4'-hydroxy-2'-butenyloxy] coumarin are proposed on the basis of spectroscopic evidence.
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two new o geranyl coumarins from the resinous exudate of Haplopappus multifolius
Fitoterapia, 2003Co-Authors: Rene Torres, Francesca Faini, Franco Delle Monache, Giuliano Delle MonacheAbstract:From the resinous exudate of leaves of Haplopappus multifolius two new coumarins were isolated and assigned the structures 6-hydroxy-7-(5'-hydroxy-3',7'-dimethylocta-2',6'-dien)-oxycoumarin (1) and 6-hydroxy-7-(7'-hydroxy-3',7'-dimethylocta-2',5'-dien)-oxy coumarin (2).
Francesca Faini - One of the best experts on this subject based on the ideXlab platform.
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chemistry and bioactivity of Haplopappus remyanus bailahuen a chilean medicinal plant
Journal of the Brazilian Chemical Society, 2011Co-Authors: Francesca Faini, Rene Torres, Cecilia Labbe, Jesus M Rodilla, Carla Delporte, Fabian JanaAbstract:Chromatography on the resinous extract of aerial parts of Haplopappus remyanus led to the isolation of 18-acetoxy-labda-7,13E-dien-15-oic acid along with the monoterpene derivatives 9-hydroxy-α-terpineol, 9-benzoyloxy-α-terpineol,7-hydroxy-9-benzoyloxy-α-terpineoland 9-benzoyloxy-(1-formyl)-α-terpineol. Structures for the new compounds are proposed on spectroscopic evidence. The presence of quercetin and five other known flavonoids identified in this study could account for the reported high antioxidant activity and the moderate topic anti-inflammatory effect on induced ear oedema. MTT assay with CCRF-CEM tumor cells showed 50% of the cytotoxic activity displayed by doxorubicin under the same conditions. Quantitative differences in chemical composition were detected in comparison with previous studies of the species that could be attributed to environmental factors.
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new phenolic esters from the resinous exudate of Haplopappus taeda
Fitoterapia, 2007Co-Authors: Francesca Faini, Rene Torres, Cecilia Labbe, Jesus M Rodilla, Lucia Silva, Franco Delle MonacheAbstract:Two new phenolic esters 9-trans-p-coumaroyloxy-alpha-terpineol (1) and 7-trans-p-coumaroyloxy-taedol (2), both endowed with free radical scavenger activity and cleroda-3,13 (E)-dien-15,18-diol (3) for which a cis stereochemistry at the decalin junction was found, were isolated from the resinous exudate from Haplopappus taeda upper parts.
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phytochemical communication new phenolic esters from the resinous exudate of Haplopappus taeda
2007Co-Authors: Francesca Faini, Rene Torres, Cecilia Labbe, Jesus M Rodilla, Lucia Silva, Franco Delle MonacheAbstract:Two new phenolic esters 9-trans-p-coumaroyloxy-α-terpineol (1) and 7-trans-p-coumaroyloxy-taedol (2), both endowed with free radical scavenger activity and cleroda-3,13 (E)-dien-15,18-diol (3) for which a cis stereochemistry at the decalin junction was found, were isolated from the resinous exudate from Haplopappus taeda upper parts. © 2007 Elsevier B.V. All rights reserved.
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antioxidant activity of coumarins and flavonols from the resinous exudate of Haplopappus multifolius
Phytochemistry, 2006Co-Authors: Rene Torres, Francesca Faini, Brenda Modak, Francisco Urbina, Cecilia Labbe, Juan GuerreroAbstract:The antioxidant activity of eight coumarins and two flavonols isolated from Haplopappus multifolius was studied with the DPPH radical method. Results show that a high concentration of phenolic coumarins and the presence of quercetin and rhamnetin in the exudates could account for the protection of the plant against oxidative stress. Structures for the coumarins 6-hydroxy-7-[(E,E)-3',7'-dimethyl-2',4',7'-octatrienyloxy] coumarin and 7-[(E)-3'-methyl-4'-hydroxy-2'-butenyloxy] coumarin are proposed on the basis of spectroscopic evidence.
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antioxidant properties and tlc characterization of four chilean Haplopappus species known as bailahuen
Journal of Ethnopharmacology, 2005Co-Authors: Hermine Vogel, Francesca Faini, Mauricio Gonzalez, Ivan Razmilic, Jaime A Rodriguez, Jose San Martin, Francisco Zuniga UrbinaAbstract:"Bailahuen" is the common name of a medicinal shrub native to Chile where this resinous herb is widely used for its liver stimulating properties. Although the official species is Haplopappus baylahuen Remy (Asteraceae), other species of the same genus are also used in different regions as "bailahuen". A thin layer chromatography (TLC) method for rapid identification of different species and detection of adulterations is described for four of the species: Haplopappus baylahuen, Haplopappus taeda Reiche, Haplopappus multifolius Phil., and Haplopappus remyanus Wedd. To confirm efficiency in all species antioxidant properties were screened in resins, infusions, and methanolic extracts by tests of lipid peroxidation in erythrocytes and free radical scavenging activity by DPPH. In both studies Haplopappus baylahuen showed the lowest antioxidant capacity. In DPPH analyses, infusion and resins of Haplopappus baylahuen also showed the lowest and Haplopappus remyanus the major inhibiting activity of free radicals, while Haplopappus multifolius proved to have the highest result when the methanolic extracts were used. The chemical characterization of the studied species showed important levels of flavonoids and coumarins, with flavonoids predominating in Haplopappus taeda, coumarins in Haplopappus multifolius and both of them in Haplopappus baylahuen and Haplopappus remyanus.
R Cremonini - One of the best experts on this subject based on the ideXlab platform.
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the intergenic spacer region of the rdna in Haplopappus gracilis nutt gray
Protoplasma, 2013Co-Authors: Ruffini M Castiglione, R Cremonini, M T Gelati, M FredianiAbstract:In this paper, we provide further information on the genome organisation of Haplopappus gracilis, one of the six angiosperms showing the lowest chromosome number, i.e. 2n = 4, by determining the nucleotide sequence of the intergenic spacer region of the ribosomal RNA genes and its cytological localization on metaphase chromosomes. DNA sequence analysis reveals the occurring of a product of 4,382 bp in length, characterised by the presence of four blocks of different repeated sequences. Our analysis also evidenced putative promoter regions with three transcription initiation sites for polymerase I, as previously reported in Artemisia absinthium, belonging to the same Asteraceae family. A fluorescent in situ hybridization with the intergenic spacer probe indicates the presence of rDNA genes only in the satellited chromosomes of H. gracilis; besides, differences in the signal intensity between homologous chromosomes were frequently observed, thus suggesting for these chromosome sites the presence of a variable number of rDNA gene copies, even if a divergent chromatin organisation in corresponding regions cannot be ruled out.
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cytological investigation of Haplopappus gracilis nutt gray 5 methylcytosine rich regions fluorochrome banding and chromatin sensitivity to dnase i digestion
Protoplasma, 2008Co-Authors: Ruffini M Castiglione, M Frediani, G Venora, R CremoniniAbstract:Haplopappus gracilis (Nutt.) Gray, one of the five known higher plants with a chromosome number of 2n = 4, was studied from a cytological point of view. The chromosome complement of this species was characterized by means of automated karyotype analysis. Moreover, the DNA methylation pattern and fluorochrome banding were determined and compared with cytological data present in the literature. DNA methylation distribution along metaphase chromosomes involved all chromosome territories evidenced by C-banding. Other methylated bands correlated positively with aceto-orcein-positive heterochromatic portions and/or with late replicating bands and/or fluorochrome bands. Some methylated bands showed differences between homologous chromosomes. These bands belonged partly to certain heterochromatic domains and partly to intercalary sites not defined by other standard banding techniques. Differences between the homologues were also indicated by our DNA content data obtained after DNase I digestion.
