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Search Results: 1 - 10 of 346 matches for " Magalis Bittner Berner "
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Efectos antibacterianos de extractos de especies del género Ugni que crecen en Chile Antibacterial effects of extracts of species of the genus Ugni that grow in Chile
Marcia Avello Lorca,Magalis Bittner Berner,José Becerra Allende
Revista Cubana de Plantas Medicinales , 2013,
Abstract: Introducción: Ugni molinae Turcz., Ugni candollei (Barnéoud) O. Berg y Ugni selkirkii (Hook. & Arn.) Berg son arbustos que se distribuyen en el centro-sur de Chile, incluido el archipiélago de Juan Fernández. Dada su similitud morfológica parece que estas especies están estrechamente relacionadas, por lo tanto, podrían compartir compuestos químicos similares, como sustancias de tipo fenólico y del tipo terpénico, con reconocida actividad antimicrobiana, los que han sido identificados en Ugni molinae, la especie con mayor distribución en Chile. Objetivo: evaluar la composición química y la actividad antibacteriana de los extractos de las especies chilenas del género Ugni, y determinar si existen variaciones entre poblaciones que están creciendo separadas geográficamente y en diferentes hábitats, como en Chile continental y el archipiélago de Juan Fernández. Métodos: se determinó el contenido y la composición de compuestos químicos por métodos espectrofotométricos en extractos obtenidos con solventes de polaridad creciente. La actividad antibacteriana se evaluó a través de inclusión en agar tripticasa frente a Pseudomonas aeruginosa, Staphyloccoccus aureus y Enterobacter aerogenes. Resultados: Ugni candollei y Ugni selkirkii presentan la mayor concentración de fenoles, flavonoides y taninos totales. Con respecto a las poblaciones de Ugni molinae, la población del archipiélago de Juan Fernández presentó la mayor concentración de compuestos fenólicos y saponinas totales. Si bien existe una tendencia en la actividad antibacteriana en los extractos metanólicos, que se correlaciona con la composición química, no se consideran grandes diferencias entre estas. Conclusiones: dado que Ugni molinae comparte características morfológicas con otras especies del género que crecen en Chile, Ugni candollei y Ugni selkirkii, también comparte características químicas. Con respecto a las poblaciones de Ugni molinae, se observan diferencias en el contenido de compuestos fenólicos y saponinas totales, quizá por las características de hábitat donde estas especies y poblaciones están creciendo. La mezcla activa de los extractos metanólicos de especies del género Ugni y las poblaciones de Ugni molinae, llamada fitocomplejo, concentra las acciones antimicrobianas para las familias de componentes descritas, sin observarse grandes diferencias entre estas. Introduction: Ugni molinae Turcz., Ugni candollei (Barneoud) O. Berg and Ugni selkirkii (Hook. & Arn.) Berg are shrubs growing in southern central Chile, including Juan Fernandez Islands. Given their morphological likeness, these s
Efectos antimicrobianos de extractos de plantas chilenas de las familias Lauraceae y Atherospermataceae
Avello Lorca,Marcia; López Canales,Carolina; Gatica Valenzuela,Carlos; Bustos Concha,Evelyn; Brieva Chait,Alejandra; Pastene Navarrete,Edgar; Bittner Berner,Magalis;
Revista Cubana de Plantas Medicinales , 2012,
Abstract: introduction: the antimicrobial activity has been reported for the essential oils of some species in the families lauraceae and atherospermataceae. the present study was conducted with three chilean species: cryptocarya alba looser (peumo) and persea lingue (ruiz & pav.) nees (lingue) from the family lauraceae, and laurelia sempervirens (ruiz & pav.) tul. (chilean laurel) from the family atherospermataceae. the morphological aspects and the popular uses of these species are the only known aspects. thorough studies of their chemical composition and biological activity are lacking. objective: to evaluate the activity of the essential oils against microorganisms and to provide information on the chemical composition of these species. methods: samples were collected in the bío-bío region and essential oils were obtained by steam distillation. chemical characterization was done using gc-ms. antimicrobial activity was evaluated against penicillium sp. and fusarium oxysporum through antifungal agar dilution and vapor diffusion assays. antibacterial tests against escherichia coli, bacillus subtilis, pseudomonas aeruginosa, and staphylococcus aureus, were carried out using agar disk and well diffusion assays. results: the results for the essential oils from the three species indicated selective activity against fungi and bacteria, suggesting that the different chemical features of these oils may play a role in their mechanisms of action. conclusions: further studies focusing efforts on developing products to control microorganisms that cause economic losses and affect human health.
Especialización en el uso de hospederos de Dictyneis asperatus (Blanchard 1851) en un fragmento de vegetación esclerófila-higrófila en la Península de Hualpén, Chile
CENTELLA,CRISTIAN; JEREZ,VIVIANE; GONZáLEZ,URCESINO; BITTNER,MAGALIS;
Revista chilena de historia natural , 2003, DOI: 10.4067/S0716-078X2003000300005
Abstract: we evaluated trophic relationships between the coleopteran d. asperatus and five potencial hosts plants (peumus boldus, lithrea caustica, cryptocarya alba, aextoxicon punctatum and luma apiculata) in a coastal forest of the hualpén peninsula (36 s). leaf shape and degree of sclerophylly were examined as possible determinants of host preferences and insect survival. although d. asperatus was significantly more abundant on p. boldus, there were no significant differences in consumption of leaves of p. boldus, l. caustica and l. apiculata. adults insects tended to stay under the concave leafs of boldo. highest and lowest survival was registered in insects fed on p. boldus (72%) and a. punctatum (26%) respectively. the concave leaf of p. boldus represents a possible refuge, and the higher abundance and survival of insects, in spite of the highly sclerophyllous nature of this species, suggests that d. asperatus is an ecological specialist in p. boldus. however, as d. asperatus is common on other plant species at other sites, it can only be considered a local specialist on p. boldus at hualpén.
Especialización en el uso de hospederos de Dictyneis asperatus (Blanchard 1851) en un fragmento de vegetación esclerófila-higrófila en la Península de Hualpén, Chile Specialization on the host use of Dictyneis asperatus (Blanchard 1851) in a fragment of sclerophyllous-higrophyllous shrublands in Península of Hualpén, Chile
CRISTIAN CENTELLA,VIVIANE JEREZ,URCESINO GONZáLEZ,MAGALIS BITTNER
Revista chilena de historia natural , 2003,
Abstract: En un fragmento de vegetación esclerófila-higrófila de la Península de Hualpén (36 S) se evaluó si existen asociaciones de tipo trófica entre D. asperatus y cinco potenciales plantas hospederas: Peumus boldus, Lithrea caustica, Cryptocarya alba, Aextoxicon punctatum y Luma apiculata. Se determinó si existe preferencia de hospedero y si esta está relacionada con la forma cóncava de las hojas, carácter esclerófilo de ellas y con la mayor sobrevivencia de los insectos. Los insectos son significativamente más abundantes en boldo, pero no existen diferencias en el consumo foliar entre boldo, litre y arrayán. Boldo y litre tienen hojas más duras respecto de olivillo y arrayán. Los insectos adultos tienden a permanecer bajo hojas cóncavas de P. boldus. La mayor y menor sobrevivencia se registró en individuos alimentados con P. boldus (72%) y A. punctatum (26%), respectivamente. La disponibilidad de refugio que pueden representar las hojas cóncavas de P. boldus, la mayor sobrevivencia y abundancia de los insectos que las consumen, a pesar de su alto nivel de esclerofilia, permitirían considerar a D. asperatus como un insecto especialista ecológico de P. boldus. El registro de D. asperatus sobre otras especies vegetales en otras áreas geográficas, permitirían considerar a esta especie como un especialista local de Hualpén. We evaluated trophic relationships between the coleopteran D. asperatus and five potencial hosts plants (Peumus boldus, Lithrea caustica, Cryptocarya alba, Aextoxicon punctatum and Luma apiculata) in a coastal forest of the Hualpén peninsula (36 S). Leaf shape and degree of sclerophylly were examined as possible determinants of host preferences and insect survival. Although D. asperatus was significantly more abundant on P. boldus, there were no significant differences in consumption of leaves of P. boldus, L. caustica and L. apiculata. Adults insects tended to stay under the concave leafs of boldo. Highest and lowest survival was registered in insects fed on P. boldus (72%) and A. punctatum (26%) respectively. The concave leaf of P. boldus represents a possible refuge, and the higher abundance and survival of insects, in spite of the highly sclerophyllous nature of this species, suggests that D. asperatus is an ecological specialist in P. boldus. However, as D. asperatus is common on other plant species at other sites, it can only be considered a local specialist on P. boldus at Hualpén.
CHEMICAL DEFENSE RESPONSES IN Eucalyptus globulus (Labill) PLANTS
CHRISTIAN TRONCOSO,JOSé BECERRA,MAGALIS BITTNER,CLAUDIA PEREZ
Journal of the Chilean Chemical Society , 2011,
Abstract: This study evaluated the expression of defense compounds by the secondary metabolism of Eucalyptus globulus plants subjected to attacks by the insect Ctenarytaina eucalypti (blue gum psyllid) and abiotic mechanical damage using gas chromatography with flame ionization detection (GC-FID) and mass detection (MS). The results show that both biological and mechanical attacks activated defense responses in the plants. We identified 34 compounds in the leaves of the treated plants. In the case of the plants damaged by C. eucalypti, four of the compounds differed from those of the control: three oxygenated monoterpenes (borneol, exo-2-hydroxy cineole and thymol) and one quinone (6-acethyl-flaviolin). In the case of the mechanical damage, five compounds differed from the control: three sesquiterpenes (alloaromadendrene, eremophilene, and caryophyllene-oxide), borneol, and 6-acethyl-flaviolin. According to the results, different compounds are biosynthesized when faced with biotic and abiotic inductions, indicating a certain level of specificity in the response of the plants to different types of damage.
Actividad de aceites esenciales de Canelo, Queule, Bailahuén y Culén frente a hongos fitopatógenos
Julio BECERRA,Magalis BITTNER,Victor HERNáNDEZ,Carolina BRINTRUP
Boletín Latinoamericano y del Caribe de Plantas Medicinales y Aromáticas , 2010,
Abstract: Los agentes da inos más comunes en las plantas son los hongos fitopatógenos. En este contexto se realizaron ensayos para determinar el porcentaje de inhibición de crecimiento de los hongos fitopatógenos al ser expuesto a aceites esenciales de cuatro plantas nativas chilenas: Drimys winteri (Canelo), Psoralea glandulosa (Culén), Gomortega keule (Queule) y Haplopappus baylahuen (bailahuén). Se realizaron ensayos cuantitativos por difusión en agar de P. glandulosa sobre Aspergillus nigra, G. keule sobre Rhizopus arrhizus, H. baylahuen sobre Fusarium oxysporum y D. winteri sobre Botritys cinérea. El crecimiento de A. nigra en placa con aceites esenciales al 1% demostró que el modo de acción sobre el hongo varía con cada aceite, resultando el aceite esencial de G. keule más activo inhibiendo un 54%, seguido de P. glandulosa (39%), H. baylahuen (38%) y D. winteri (36%).
Fatty acid composition of three species of Codium (Bryopsidales, Chlorophyta) in Chile
Goecke,Franz; Hernández,Víctor; Bittner,Magalis; González,Mariela; Becerra,José; Silva,Mario;
Revista de biología marina y oceanografía , 2010, DOI: 10.4067/S0718-19572010000200014
Abstract: the fatty acid compositions of algae show characteristic patterns accoding to species. this paper is the first to identify and compare the main fatty acids of the two endemic codium species: c. dimorphum and c. fernandezianum found in chile. in addition the fatty acids of the introduced species c. fragile were investigated. palmitic acid was shown to be the main fatty acid, comprising between 28 to 54%, followed by oleic and linolenic acids. we also confirm, for the first time, the presence of hexadecatrienoic acid (c16:3) in all three species, which is suggested to be a characteristic fatty acid for codium genus, so this can be used in chemotaxonomy for these species around the world
Variation in phenolic compounds of Ugni molinae populations and their potential use as antioxidant supplement
Marcia A. Avello,Edgar R. Pastene,Evelyn D. Bustos,Magalis L. Bittner
Revista Brasileira de Farmacognosia , 2012, DOI: 10.1590/s0102-695x2012005000122
Abstract: In the present work we carried out a comparative study of total phenolic contents and antioxidant capacity of aqueous leaf extracts of Ugni molinae Turcz., Myrtaceae (infusion and Soxhlet extracted) prepared from continent and Juan Fernández Island samples. The results revealed that total phenol content (TPC), tannins (TTC) and flavonoids (TFC) for U. molinae extracts (infusion and Soxhlet extracts) from island leaves were 38.5, 56.7 and 37.5% higher than those obtained with leaves from the continent, respectively. Also, HPLC profiles showed important differences between U. molinae populations. In vitro antioxidant capacity (scavenging of DPPH radical) for 1% infusion and aqueous extract (Soxhlet method) of U. molinae from island samples, was 15% greater than from continent samples. Further, in vivo impact of U. molinae intake (1% infusion) was studied in plasma samples obtained from healthy volunteers. Participants that consumed tea prepared with leaves from island population showed higher TBARS reduction and plasma antioxidant capacity (TEAC-CUPRAC) than those who consumed tea prepared with leaves from continental population. The conditions of the territory in which U. molinae populations growth could explain the differences in their composition and activity. According to results, island U. molinae populations could be an important source of study for the development of an antioxidant supplement, and thereby contribute to the use of this species that has becoming an ecological problem in the island.
Variation in phenolic compounds of Ugni molinae populations and their potential use as antioxidant supplement
Marcia A. Avello,Edgar R. Pastene,Evelyn D. Bustos,Magalis L. Bittner
Revista Brasileira de Farmacognosia , 2013,
Abstract: In the present work we carried out a comparative study of total phenolic contents and antioxidant capacity of aqueous leaf extracts of Ugni molinae Turcz., Myrtaceae (infusion and Soxhlet extracted) prepared from continent and Juan Fernández Island samples. The results revealed that total phenol content (TPC), tannins (TTC) and flavonoids (TFC) for U. molinae extracts (infusion and Soxhlet extracts) from island leaves were 38.5, 56.7 and 37.5% higher than those obtained with leaves from the continent, respectively. Also, HPLC profiles showed important differences between U. molinae populations. In vitro antioxidant capacity (scavenging of DPPH radical) for 1% infusion and aqueous extract (Soxhlet method) of U. molinae from island samples, was 15% greater than from continent samples. Further, in vivo impact of U. molinae intake (1% infusion) was studied in plasma samples obtained from healthy volunteers. Participants that consumed tea prepared with leaves from island population showed higher TBARS reduction and plasma antioxidant capacity (TEAC-CUPRAC) than those who consumed tea prepared with leaves from continental population. The conditions of the territory in which U. molinae populations growth could explain the differences in their composition and activity. According to results, island U. molinae populations could be an important source of study for the development of an antioxidant supplement, and thereby contribute to the use of this species that has becoming an ecological problem in the island.
EFFECTS OF ESSENTIAL OILS FROM FIVE PLANT SPECIES AGAINST THE GRANARY WEEVILS SITOPHILUS ZEAMAIS AND ACANTHOSCELIDES OBTECTUS (COLEóPTERA)
MAGALIS L. BITTNER,MARíA E. CASANUEVA,CECILIA C ARBERT,MILENKO A AGUILERA
Journal of the Chilean Chemical Society , 2008,
Abstract: Essential oils obtained from Gomortega keule, Laurelia sempervirens, Origanum vulgare, Eucalyptus globulus, and Thymus vulgaris were analyzed by gas chromatography and gas chromatography-mass spectrometry and evaluated for their toxicity against adults of Sitophilus zeamais (Motschulky) and Acanthoscelides obtectus (Say) (Coleóptera). Contact toxicity was assayed by impregnating filter paper discs with the oils. The amount of essential oils applied in each desiccator (4 1 capacity) was 4, 8, 16, or 32 ul, corresponding to 1, 2, 4, or 8 fj.1/1 air. The results showed significant differences between the tested dosages and exposure periods of the essential oils. Although desirable insecticidal activities against A obtectus were achieved with the essential oils of all five plants, the oils from G. keule and L. sempervirens were the most effective at 96 h. On the other hand, the essential oils of E. globulus and T. vulgaris were most effective against S. zeamais. In all plant species, higher doses or longer exposure periods were more effective against both insects. No mortality was observed in the control group (acetone only) of each species. Therefore, these results suggest that essential oils from the studied plants may be used against insect pests in grain storage
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