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NOTAS SOBRE DICTYOTA PFAFFII Y D. HUMIFUSA (DICTYOTALES, PHAEOPHYTA)
Bula-Meyer,Germán;
Boletín de Investigaciones Marinas y Costeras - INVEMAR , 1994,
Abstract: dictyota pfaffii schnetter and d. humifusa h?rnig, schnetter et coppejans are two small species whose taxonomic boundary is not clear. they are so similar, that there are not reasons to consider these two species from the colombian caribbean, living in the same enviroments, different.
Diterpenes from the Brown Alga Dictyota crenulata  [PDF]
Joel Campos De-Paula,Ludmila Bomeny Bueno,Diana Negr?o Cavalcanti,Yocie Yoneshigue-Valentin,Valéria Laneuville Teixeira
Molecules , 2008, DOI: 10.3390/molecules13061253
Abstract: The crude extract of the Brazilian brown alga Dictyota crenulata was analyzed by NMR spectroscopy and HRGC-MS techniques. Seven diterpenes were identified: pachydictyol A, dictyodial, 4β-hydroxydictyodial A, 4β-acetoxydictyodial A, isopachydictyol A, dictyol C and dictyotadiol. Xeniane diterpenes have previously been found in D. crenulata from the Pacific Ocean. The results characterize D. crenulata as a species that provides prenylated guaiane (group I) and xeniane diterpenes (group III), thus making it a new source of potential antiviral products.
Diterpenes from marine brown alga Dictyota guineensis (Dictyotaceae, Phaeophyceae)
De-Paula, Joel Campos;Cavalcanti, Diana Negr?o;Yoneshigue-Valentin, Yocie;Teixeira, Valéria Laneuville;
Revista Brasileira de Farmacognosia , 2012, DOI: 10.1590/S0102-695X2012005000071
Abstract: the crude extract of the marine brown alga dictyota guineensis was analyzed by high-resolution gas chromatography-mass spectrometry (hrgc-ms). five diterpenes were identified: dictyol e (the most abundant diterpene), dictyotadiol, dictyoxide, isopachydictyol a and pachydictyol a, all diterpenes from the chemical group i, i.e., mainly prenylated derivatives of known sesquiterpene skeletons that result from a first cyclization of geranyl-geraniol between positions 1 and 10. these diterpenes are known for their activity against bacteria, fungi and other activities. the results characterize d. guineensis as a species that yields exclusively diterpenes from group i, with low oxidation and low structural complexity. on brazilian coasts, only d. mertensii provides exclusively prenylated guaiane diterpenes. although d. guineensis presents alternate branches and fixing by rhizoidal branches, it is easily distinguishable from d. mertensii by the much narrower stem, short stature and flabelliform habit of the former species. on the other hand, both species have been characterized as producers of diterpenes of group i, in particular, prenylated guaiane. however, d. guineensis has a majority dictyol e in the lipophilic extract, while d. mertensii produces more complex prenylated guaianes, like dictyol h.
Diterpenes from marine brown alga Dictyota guineensis (Dictyotaceae, Phaeophyceae)  [cached]
Joel Campos De-Paula,Diana Negr?o Cavalcanti,Yocie Yoneshigue-Valentin,Valéria Laneuville Teixeira
Revista Brasileira de Farmacognosia , 2012,
Abstract: The crude extract of the marine brown alga Dictyota guineensis was analyzed by high-resolution gas chromatography-mass spectrometry (HRGC-MS). Five diterpenes were identified: dictyol E (the most abundant diterpene), dictyotadiol, dictyoxide, isopachydictyol A and pachydictyol A, all diterpenes from the chemical group I, i.e., mainly prenylated derivatives of known sesquiterpene skeletons that result from a first cyclization of geranyl-geraniol between positions 1 and 10. These diterpenes are known for their activity against bacteria, fungi and other activities. The results characterize D. guineensis as a species that yields exclusively diterpenes from group I, with low oxidation and low structural complexity. On Brazilian coasts, only D. mertensii provides exclusively prenylated guaiane diterpenes. Although D. guineensis presents alternate branches and fixing by rhizoidal branches, it is easily distinguishable from D. mertensii by the much narrower stem, short stature and flabelliform habit of the former species. On the other hand, both species have been characterized as producers of diterpenes of group I, in particular, prenylated guaiane. However, D. guineensis has a majority dictyol E in the lipophilic extract, while D. mertensii produces more complex prenylated guaianes, like dictyol H.
Vasorelaxation, Induced by Dictyota pulchella (Dictyotaceae), a Brown Alga, Is Mediated via Inhibition of Calcium Influx in Rats  [PDF]
Thyago M. Queiroz,Natália T. Machado,Fabíola F. Furtado,Abrah?o A. Oliveira-Filho,Maria C. Alustau,Camila S. Figueiredo,George E. C. Miranda,José M. Barbosa-Filho,Valdir A. Braga,Isac A. Medeiros
Marine Drugs , 2011, DOI: 10.3390/md9102075
Abstract: This study aimed to investigate the cardiovascular effects elicited by Dictyota pulchella, a brown alga, using in vivo and in vitro approaches. In normotensive conscious rats, CH 2Cl 2/MeOH Extract (CME, 5, 10, 20 and 40 mg/kg) from Dictyota pulchella produced dose-dependent hypotension (?4 ± 1; ?8 ± 2; ?53 ± 8 and ?63 ± 3 mmHg) and bradycardia (?8 ± 6; ?17 ± 11; ?257 ± 36 and ?285 ± 27 b.p.m.). In addition, CME and Hexane/EtOAc Phase (HEP) (0.01–300 μg/mL) from Dictyota pulchella induced a concentration-dependent relaxation in phenylephrine (Phe, 1 μM)-pre-contracted mesenteric artery rings. The vasorelaxant effect was not modified by the removal of the vascular endothelium or pre-incubation with KCl (20 mM), tetraethylammonium (TEA, 3 mM) or tromboxane A 2 agonist U-46619 (100 nM). Furthermore, CME and HEP reversed CaCl 2-induced vascular contractions. These results suggest that both CME and HEP act on the voltage-operated calcium channel in order to produce vasorelaxation. In addition, CME induced vasodilatation after the vessels have been pre-contracted with L-type Ca 2+ channel agonist (Bay K 8644, 200 nM). Taken together, our data show that CME induces hypotension and bradycardia in vivo and that both CME and HEP induce endothelium-independent vasodilatation in vitro that seems to involve the inhibition of the Ca 2+ influx through blockade of voltage-operated calcium channels.
Dolabelladienetriol, a Compound from Dictyota pfaffii Algae, Inhibits the Infection by Leishmania amazonensis  [PDF]
Deivid Costa Soares,Teresa C. Calegari-Silva,Ulisses G. Lopes,Valéria L. Teixeira,Izabel C. N. de Palmer Paix?o,Claudio Cirne-Santos,Dumith Chequer Bou-Habib,Elvira M. Saraiva
PLOS Neglected Tropical Diseases , 2012, DOI: 10.1371/journal.pntd.0001787
Abstract: Background Chemotherapy for leishmaniasis, a disease caused by Leishmania parasites, is expensive and causes side effects. Furthermore, parasite resistance constitutes an increasing problem, and new drugs against this disease are needed. In this study, we examine the effect of the compound 8,10,18-trihydroxy-2,6-dolabelladiene (Dolabelladienetriol), on Leishmania growth in macrophages. The ability of this compound to modulate macrophage function is also described. Methodology/Principal Findings Leishmania-infected macrophages were treated with Dolabelladienetriol, and parasite growth was measured using an infectivity index. Nitric oxide (NO), TNF-α and TGF-β production were assayed in macrophages using specific assays. NF-kB nuclear translocation was analyzed by western blot. Dolabelladienetriol inhibited Leishmania in a dose-dependent manner; the IC50 was 44 μM. Dolabelladienetriol diminished NO, TNF-α and TGF-β production in uninfected and Leishmania-infected macrophages and reduced NF-kB nuclear translocation. Dolabelladienetriol inhibited Leishmania infection even when the parasite growth was exacerbated by either IL-10 or TGF-β. In addition, Dolabelladienetriol inhibited Leishmania growth in HIV-1-co-infected human macrophages. Conclusion Our results indicate that Dolabelladienetriol significantly inhibits Leishmania in macrophages even in the presence of factors that exacerbate parasite growth, such as IL-10, TGF-β and HIV-1 co-infection. Our results suggest that Dolabelladienetriol is a promising candidate for future studies regarding treatment of leishmaniasis, associated or not with HIV-1 infection.
Two New Species of the Genus Dictyota (Phaeophyceae: Dictyotales) from the Mexican Caribbean  [PDF]
Jorge G. Lozano-Orozco, Abel Sentíes, Olivier De Clerck, Kurt M. Dreckmann, Jhoana Díaz-Larrea
American Journal of Plant Sciences (AJPS) , 2015, DOI: 10.4236/ajps.2015.615251
Abstract: During a molecular characterization of the genus Dictyota J. V. Lamouroux (Phaeophyceae, Dictyotales) along the Mexican coasts of the Gulf of Mexico and the Mexican Caribbean, using psbA and cox1 genes, it was found that two particular collections did not match with the sequences published for a total of 39 species of Dictyota. For each gene, both collections diverged in high-uncorrected “p” distance values with respect to other related species. This high genetic divergence was corroborated by morphological analysis. Hence, we proposed Dictyota mayae J. Lozano-Orozco & Sentíes and Dictyota pedrochei J. Lozano-Orozco & Sentíes as new species.
Pachydictyols B and C: New Diterpenes from Dictyota dichotoma Hudson  [PDF]
Ghada S. E. Abou-El-Wafa,Mohamed Shaaban,Khaled A. Shaaban,Mohamed E. E. El-Naggar,Armin Maier,Heinz H. Fiebig,Hartmut Laatsch
Marine Drugs , 2013, DOI: 10.3390/md11093109
Abstract: Two new diterpenoids, pachydictyol B ( 1a/ 1b) and C ( 2), were isolated from the dichloromethane extract of the marine brown alga, Dictyota dichotoma, collected from the Red Sea coast of Egypt, along with the known metabolites, pachydictyol A ( 3a), dictyol E ( 4), cis-africanan-1α-ol ( 5a), fucosterol ( 6), tetrahydrothiophen-1,1-dioxide and poly-β-hydroxybutyric acid. GC-MS analysis of the nonpolar fractions also indicated the presence of β-bourbonene and nonanal, along with three hydrocarbons and five fatty acids or their simple derivatives, respectively. GC-MS analysis of the unsaponifiable algal petroleum ether extract revealed the presence of a further eight compounds, among them 2,2,6,7-tetramethyl-10-oxatricyclo[4.3.0.1(1,7)]decan-5-one ( 7), N-(4-bromo- n-butyl)-pipe ridin-2-one ( 8) and tert-hexadecanethiol. Structures 1– 6 were assigned by 1D and 2D NMR, mass spectra (EI, CI, HREI and HRESI) and by comparison with data from related structures. The crude algal extract was potently active against the breast carcinoma tumor cell line, MCF7 (IC 50 = 0.6 μg mL ?1); pachydictyol B ( 1a) and dictyol E ( 4) showed weak antimicrobial properties, and the other compounds were inactive. Pachydictyols B ( 1a) and C ( 2) demonstrated a weak and unselective cytotoxicity against twelve human tumor cell lines with a mean IC 50 of >30.0 μM.
EFECTO DE LA SEDIMENTACIóN EN EL RECLUTAMIENTO DE LAS MACROALGAS DICTYOTA SPP. Y LOBOPHORA VARIEGATA: UN ESTUDIO EXPERIMENTAL EN EL PARQUE NACIONAL NATURAL TAYRONA, CARIBE COLOMBIANO
Flórez-Leiva,Lennin; Rangel-Campo,Alejandro; Díaz-Ruiz,Martha; Venera-Pontón,Dagoberto E.; Díaz-Pulido,Guillermo;
Boletín de Investigaciones Marinas y Costeras - INVEMAR , 2010,
Abstract: sedimentation is frequently associated with coral reef degradation. however, there are few experimental studies evaluating the impacts of this process on the dynamics of algal recruitment on coral reefs. in a field experiment, we manipulated the levels of sedimentation and examined the impacts on the recruitment and growth of the brown macroalgae dictyota spp. and lobophora variegata, in two localities (chengue and granate) on the tayrona national natural park, colombian caribbean. we found considerable variability in the responses of algae to sedimentation. this variability depended on the levels of sediments used, the type of algae employed and the population parameter considered (recruitment or growth). sediment addition generally had a negative effect on the recruitment and early growth of the alga dictyota spp. in contrast, sediment addition did not affect the recruitment of l. variegata, while sediment removal had a negative effect on recruitment. the locality with higher sedimentation rates (granate) generally had lower recruitment and growth of both algae than that of the other locality with lower sedimentation levels (chengue). our study indicates that there is substantial variability and complexity in the responses of reef algae to the effects of sedimentation. the results also suggest that the process of reef degradation can modify early population dynamics of benthic algae, with important implications for understanding the ecology of reef degradation.
El género Dictyota (Phaeophyceae, Dictyotales) en el Caribe Venezolano The genus Dictyota (Phaeophiceae, Dictyotales) in the Venezuelan Caribbean
María A. SOLé,Ernesto FOLDATS
Acta Botánica Venezuelica , 2003,
Abstract: RESUMEN El género Dictyota, de distribución cosmopolita, comprende unas 70 especies con una presencia importante en la región del Caribe. En Venezuela, el género está distribuido en toda la costa, siendo uno de los más frecuentes y representativos. En este trabajo se realiza el estudio taxonómico del género para el país con material de herbario y colecciones recientes; se aportan descripciones completas y figuras, se discute la identidad taxonómica de cada especie, se consideran aspectos de su fenología, distribución local y regional. A través de este estudio se estableció la presencia de 14 especies en Venezuela que representan el 70% de lo reportado para la región del Atlántico occidental. La presencia escasa de gametófitos en el material estudiado coincide con la paucicidad de éstos observada en poblaciones naturales. ABSTRACT The genus Dictyota, which has a cosmopolitan distribution, comprises about 70 species with an important presence in the Caribbean. In Venezuela, the genus is distributed all around the coast, and it is one of the most frequent and representative. In this work, taxonomic revision of the genus was carried out with herbarium specimens and recent collections. Complete descriptions and figures are given together with a discussion on the taxonomic identity of each species. Phenology aspects and local and regional distribution are considered. Through this study, the presence of 14 species in Venezuela was established which represents a report of 70% for the western Atlantic region. The rare presence of gametophytes in the studied material coincide with the uncommon occurrence in natural populations.
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