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Yolanda Freile-pelegrín - One of the best experts on this subject based on the ideXlab platform.
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Enhanced Antitumoral Activity of Extracts Derived from Cultured Udotea flabellum (Chlorophyta)
Evidence-based complementary and alternative medicine : eCAM, 2011Co-Authors: Rosa Moo-puc, Daniel Robledo, Yolanda Freile-pelegrínAbstract:Very few studies have been performed to evaluate the effect of culture conditions on the production or activity of active metabolites in algae. Previous studies suggest that the synthesis of bioactive compounds is strongly influenced by irradiance level. To investigate whether the antiproliferative activity of Udotea flabellum extracts is modified after cultivation, this green alga was cultured under four photon flux densities (PFD) for 30 days. After 10, 20, and 30 days, algae were extracted with dichloromethane: methanol and screened for antiproliferative activity against four human cancer cell lines (laryngeal—Hep-2, cervix—HeLa, cervix squamous—SiHa and nasopharynx—KB) by SRB assay. Lipid and phenol content were evaluated by standardized methods on algae organic extracts. After 10 days of cultivation, organic U. flabellum extracts showed a significant increase in antiproliferative activity on Hela and SiHa cells when compared to noncultured algae extracts. Extracts obtained after 10 and 20 days of culture were active on KB and Hep-2 cells. Total phenol and polyunsaturated fatty acid content in organic extracts changed with cultivation time but not by irradiance treatment. Extracts from U. flabellum obtained after 10 and 20 days of culture have been selected for fractionation and isolation of active compounds.
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Abstract B78: In vitro cytotoxic and antiproliferative activitiess of marine macroalgae from Yucatan, Mexico
Cancer Prevention Research, 2010Co-Authors: Daniel Robledo, Yolanda Freile-pelegrínAbstract:Extracts from 27 marine algal species (14 Rhodophyta, 5 Phaeophyta and 8 Chlorophyta) from the Yucatan peninsula (Mexico) were evaluated for cytotoxic and anti‐roliferative activity by 3[4,5‐dimethylthiazole‐2‐yl]‐2,5‐diphenyltetrazolium bromide (MTT) and sulforhodamine B (SRB) assays, respectively. In order to determine the specificity of the cytotoxic activity on tumor cells selective index (SI) was also calculated. The following cancer cell lines were employed: normal canine kidney cells (MDCK), human laryngeal carcinoma (Hep‐2), human cervix adenocarcinoma (HeLa) and human nasopharynx carcinoma (KB). The results indicated that 44 and 51% of algal species tested showed cytotoxic and anti‐roliferative activity, respectively. Most of the cytotoxic extracts were species belong to Chlorophyta, Udotea flabellum and Udotea conglutinate showed the highest cytotoxic activity on all cancer cell lines. For Rhodophyta, the extract of Bryothamnion triquetrum showed an outstanding selective cytotoxicity against Hep‐2 cells (CC50 8.29 µg mL−1 with SI=12.04). Two out of five species of Phaeophyta tested (Lobophora variegata and Dictyota caribaea) showed high cytotoxicity activity on KB cell line. The data show that these extracts are potential source of compounds for prevention of certain cancer diseases. Citation Information: Cancer Prev Res 2010;3(1 Suppl):B78.
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In vitro cytotoxic and antiproliferative activities of marine macroalgae from Yucatán, Mexico
Ciencias Marinas, 2009Co-Authors: Rosa Moo-puc, Daniel Robledo, Yolanda Freile-pelegrínAbstract:Extracts from 27 marine algal species (14 Rhodophyta, 5 Phaeophyta, and 8 Chlorophyta) from the Yucatan Peninsula (Mexico) were evaluated for cytotoxic and antiproliferative activity by 3(4,5-dimethylthiazole-2-yl)-2,5 diphenyltetrazolium bromide (MTT) and sulforhodamine B (SRB) assays, respectively. To determine the specificity of cytotoxic activity against tumor cells, the selective index (SI) was also calculated. The following cancer cell lines were employed: normal canine kidney (MDCK) cells, human laryngeal carcinoma (Hep-2) cells, human cervical adenocarcinoma (HeLa) cells, and human nasopharyngeal carcinoma (KB) cells. The results indicated that 44% and 51% of the algal species tested showed cytotoxic and antiproliferative activity, respectively. Most of the cytotoxic extracts were from species of Chlorophyta, with Udotea flabellum and U. conglutinate showing the highest cytotoxic activity against all the cancer cell lines. For Rhodophyta, the Bryothamnion triquetrum extract showed outstanding selective cytotoxicity against Hep-2 cells (CC50 8.29 μg mL–1, SI = 12.04). Two of the five species of Phaeophyta tested (Lobophora variegata and Dictyota caribaea) showed high cytotoxicity activity against the KB cell line. The data show that these species are a potential source of compounds for the treatment of certain cancer diseases. Los extractos de 27 especies de algas marinas (14 Rhodophyta, 5 Phaeophyta y 8 Chlorophyta) recolectadas en la peninsula de Yucatan (Mexico) fueron evaluados para probar su actividad citotoxica y antiproliferativa usando los ensayos de 3[4,5-dimetiltiazol-2-il]-2,5-bromuro de difeniltetrazolio (MTT) y sulforodamina B (SRB), respectivamente. Para determinar la especificidad de la actividad citotoxica en las celulas tumorales, el indice de selectividad (IS) fue tambien calculado. Para lo anterior fueron empleadas las siguientes lineas celulares: celulas normales de rinon caninino (MDCK), celulas de carcinoma humano laringeo (Hep-2), celulas de adenocarcinoma humano de la cervix (HeLa) y celulas de carcinoma humano nasoafaringeo (KB). Los resultados indicaron que 44% y 51% de las especies exhibieron actividad citotoxica y antiproliferativa, respectivamente. La mayoria de los extractos citotoxicos fueron de las especies pertenecientes a la division Chlorophyta, siendo Udotea flabellum y U. conglutinata las especies que mostraron la mayor actividad citotoxica selectiva sobre todas las lineas celulares tumorales. Para la division Rhodophyta, el extracto de Bryothamnion triquetrum tuvo una destacable citotoxicidad selectiva contra las celulas Hep-2 (CC50 8.29 μg mL–1 con SI = 12.04). Dos de las cinco especies de Phaeophyta probadas (Lobophora variegata y Dictyota caribaea) mostraron alta actividad citotoxica sobre la linea celular KB. Los resultados muestran que estos extractos son una fuente prometedora de compuestos para el tratamiento de algunos tipos de cancer.
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Evaluation of selected tropical seaweeds for in vitro anti-trichomonal activity.
Journal of ethnopharmacology, 2008Co-Authors: R. Moo-puc, Daniel Robledo, Yolanda Freile-pelegrínAbstract:Abstract Ethnopharmacological relevance Human parasitic infections are a serious problem in tropical and sub-tropical developing countries. Trichomoniasis, responsible for the annual infection of 180 million people, is a common sexually transmitted disease caused by the protozoan Trichomonas vaginalis . Traditionally seaweeds have been used in folk medicine by coastal people in Asia and the Caribbean to treat parasitic infections and are a valuable source of novel anti-trichomonals. Aim of the study In our search for therapeutical alternatives to anti-protozoal chemotherapy, we collected a selection of 25 tropical seaweeds (12 Rhodophyta, 5 Phaeophyta and 8 Chlorophyta) from the coast of Yucatan (Mexico) in order to undertake ethnopharmacological and chemotaxonomic investigations. Materials and methods Organic algal extracts were tested for their anti-trichomonal properties on the growth inhibition of Trichomonas vaginalis . The cytotoxicity of seaweed extracts on mammal cell lines was also assessed. Results The results indicated that 44% of the seaweeds studied had high to moderate anti-trichomonal activity. Lobophora variegata and Udotea conglutinata showed the maximal anti-trichomonal activity with IC 50 values of 1.39 and 1.66 μg/ml, respectively, with good selectivity. Conclusions Lobophora variegata and Udotea conglutinata demonstrated promising anti-trichomonal potential and have been selected for further bio-guided fractionation and isolation of active anti-trichomonal compounds.
Hugo Alexandre Oliveira Rocha - One of the best experts on this subject based on the ideXlab platform.
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Anti-Thrombin, Anti-Adhesive, Anti-Migratory, and Anti-Proliferative Activities of Sulfated Galactans From the Tropical Green Seaweed, Udotea flabellum
Marine drugs, 2018Co-Authors: Maxsuell Lucas Mendes Marques, Fernando Bastos Presa, Rony Lucas Silva Viana, Leandro Silva Costa, Mariana Santana Santos Pereira Costa, Monica Oliveira Rocha Amorim, D. L. Bellan, M. Alves, Edvaldo S. Trindade, Hugo Alexandre Oliveira RochaAbstract:In this study, sulfated polysaccharide-rich extracts were isolated from 22 tropical seaweeds (4 red, 11 brown, and 7 green) found in northeastern Brazil, and evaluated for the role of anticoagulant agents. Fifteen of the extracts showed anticoagulant activity, including all the extracts from green seaweeds. Udotea flabellum (a green seaweed) extract was the most potent, requiring an amount of only 3 µg to double the plasma coagulation time in the activated partial thromboplastin time test. A similar result was obtained with 1 µg of heparin. Two sulfated homogalactans with anticoagulant activity, F-I (130 kDa) and F-II (75 kDa), were isolated from this extract using several bio-guided purification steps. Their anticoagulant activity, as well as properties related to antitumor activity (anti-proliferative, anti-adhesive, and anti-migratory), were accessed. Their anticoagulant activities were close to that of heparin. We found that F-I and F-II (0.5–10 μg/mL) were not able to directly inhibit thrombin. In the presence of anti-thrombin, F-I (0.5 μg/mL) was more effective than heparin (0.5 μg/mL) in inhibiting thrombin, while F-II showed similar effects as heparin. F-I and F-II also inhibited B16-F10 (murine melanoma cells) adhesion, migration, and proliferation on a fibronectin-coated surface, but not on laminin- or collagen I-coated surfaces. Except for the antiproliferative activity, the other effects of F-I and F-II were eliminated upon their desulfation (~50%), indicating that the degree of sulfation is not as important for F-I and F-II anti-proliferative activity as the sulfation position. Taken together, the results provide strong evidence for the potential utility of sulfated galactans from U. flabellum, making these compounds an interesting option for future investigations that aim to design new anticoagulant/antitumor agents.
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The Protective Role of Sulfated Polysaccharides from Green Seaweed Udotea flabellum in Cells Exposed to Oxidative Damage.
Marine drugs, 2018Co-Authors: Fernando Bastos Presa, Maxsuell Lucas Mendes Marques, Rony Lucas Silva Viana, Leonardo Thiago Duarte Barreto Nobre, Leandro Silva Costa, Hugo Alexandre Oliveira RochaAbstract:Seaweed is a rich source of bioactive sulfated polysaccharides. We obtained six sulfated polysaccharide-rich fractions (UF-0.3, UF-0.5, UF-0.6, UF-0.7, UF-1.0, and UF-2.0) from the green seaweed Udotea flabellum (UF) by proteolytic digestion followed by sequential acetone precipitation. Biochemical analysis of these fractions showed that they were enriched with sulfated galactans. The viability and proliferative capacity of 3T3 fibroblasts exposed to FeSO4 (2 µM), CuSO4 (1 µM) or ascorbate (2 mM) was not affected. However, these cells were exposed to oxidative stress in the presence of FeSO4 or CuSO4 and ascorbate, which caused the activation of caspase-3 and caspase-9, resulting in apoptosis of the cells. We also observed increased lipid peroxidation, evaluated by the detection of malondialdehyde and decreased glutathione and superoxide dismutase levels. Treating the cells with the ultrafiltrate fractions (UF) fractions protected the cells from the oxidative damage caused by the two salts and ascorbate. The most effective protection against the oxidative damage caused by iron was provided by UF-0.7 (1.0 mg/mL); on treatment with UF-0.7, cell viability was 55%. In the case of copper, cell viability on treatment with UF-0.7 was ~80%, but the most effective fraction in this model was UF-2.0, with cell viability of more than 90%. The fractions, mainly UF-0.7 and UF-2.0, showed low iron chelating activity, but high copper chelating activity and total antioxidant capacity (TAC). These results suggested that some of their protective mechanisms stem from these properties.
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Antimalarial Activities of Seaweeds Spatoglossum schroederi, Gracilaria birdiae and Udotea flabellum from Rio Grande do Norte Coast, Brazil
2015Co-Authors: Gracielle Rodrigues Dantas, Hugo Alexandre Oliveira Rocha, Rodrigo C. N. Amorim, Luis Francisco Rocha Silva, Adrian Martin Pohlit, Valter Ferreira De Andrade-netoAbstract:Aim : The present study aimed to evaluate the antimalarial activity in vitro and in vivo of algae extracts, Spatoglossumschroederi , Gracilariabirdiae and Udotea flabellum . Methods : Due to the emergence of resistant strains, the research to development for new antimalarial drugs is needed. It is known that one of the most promising sources for the development of new anti-malarial drugs is natural products. Therefore, tests were performed in vitro with Plasmodium falciparum 3D7 strain, and cell cytotoxicity assay (MTT assay) with BGM cells and macrophages, acute toxicity test in vivo and in vivo tests on murine model of Plasmodium berghei . Results : The algae extracts showed cytotoxicity only at the highest concentrations tested. It was not observed in vivo toxicity for the amount used. Spatoglossumshroederi and Udotea flabellum algae were active in vivo for the amount 500mg/kg, with reduction of 52.95% and 44.60% on the fifth day and 37.39% and 54.67% on the seventh day respectively. Conclusion : Data showed that the present bioactive components in these algae can be promising for the development of new antimalarial drugs; attemptsto purifythese compoundsare in progressfor furtherbiological assays.
Daniel Robledo - One of the best experts on this subject based on the ideXlab platform.
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Enhanced Antitumoral Activity of Extracts Derived from Cultured Udotea flabellum (Chlorophyta)
Evidence-based complementary and alternative medicine : eCAM, 2011Co-Authors: Rosa Moo-puc, Daniel Robledo, Yolanda Freile-pelegrínAbstract:Very few studies have been performed to evaluate the effect of culture conditions on the production or activity of active metabolites in algae. Previous studies suggest that the synthesis of bioactive compounds is strongly influenced by irradiance level. To investigate whether the antiproliferative activity of Udotea flabellum extracts is modified after cultivation, this green alga was cultured under four photon flux densities (PFD) for 30 days. After 10, 20, and 30 days, algae were extracted with dichloromethane: methanol and screened for antiproliferative activity against four human cancer cell lines (laryngeal—Hep-2, cervix—HeLa, cervix squamous—SiHa and nasopharynx—KB) by SRB assay. Lipid and phenol content were evaluated by standardized methods on algae organic extracts. After 10 days of cultivation, organic U. flabellum extracts showed a significant increase in antiproliferative activity on Hela and SiHa cells when compared to noncultured algae extracts. Extracts obtained after 10 and 20 days of culture were active on KB and Hep-2 cells. Total phenol and polyunsaturated fatty acid content in organic extracts changed with cultivation time but not by irradiance treatment. Extracts from U. flabellum obtained after 10 and 20 days of culture have been selected for fractionation and isolation of active compounds.
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Research Article Enhanced Antitumoral Activity of Extracts Derived from Cultured Udotea flabellum (Chlorophyta)
2011Co-Authors: Rosa Moo-puc, Daniel Robledo, A Freile-pelegrin, Unidad Investigación, Médica Yucatán, Unidad Médica, Alta Especialidad, Centro Médico, Ignacio García TéllezAbstract:Copyright © 2011 Rosa Moo-Puc et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Very few studies have been performed to evaluate the effect of culture conditions on the production or activity of active metabolites in algae. Previous studies suggest that the synthesis of bioactive compounds is strongly influenced by irradiance level. To investigate whether the antiproliferative activity of Udotea flabellum extracts is modified after cultivation, this green alga was cultured under four photon flux densities (PFD) for 30 days. After 10, 20, and 30 days, algae were extracted with dichloromethane: methanol and screened for antiproliferative activity against four human cancer cell lines (laryngeal—Hep-2, cervix—HeLa, cervix squamous— SiHa and nasopharynx—KB) by SRB assay. Lipid and phenol content were evaluated by standardized methods on algae organic extracts. After 10 days of cultivation, organic U. flabellum extracts showed a significant increase in antiproliferative activity on Hela and SiHa cells when compared to noncultured algae extracts. Extracts obtained after 10 and 20 days of culture were active on KB and Hep-2 cells. Total phenol and polyunsaturated fatty acid content in organic extracts changed with cultivation time but not by irradiance treatment. Extracts from U. flabellum obtained after 10 and 20 days of culture have been selected for fractionation and isolation of active compounds. 1
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Abstract B78: In vitro cytotoxic and antiproliferative activitiess of marine macroalgae from Yucatan, Mexico
Cancer Prevention Research, 2010Co-Authors: Daniel Robledo, Yolanda Freile-pelegrínAbstract:Extracts from 27 marine algal species (14 Rhodophyta, 5 Phaeophyta and 8 Chlorophyta) from the Yucatan peninsula (Mexico) were evaluated for cytotoxic and anti‐roliferative activity by 3[4,5‐dimethylthiazole‐2‐yl]‐2,5‐diphenyltetrazolium bromide (MTT) and sulforhodamine B (SRB) assays, respectively. In order to determine the specificity of the cytotoxic activity on tumor cells selective index (SI) was also calculated. The following cancer cell lines were employed: normal canine kidney cells (MDCK), human laryngeal carcinoma (Hep‐2), human cervix adenocarcinoma (HeLa) and human nasopharynx carcinoma (KB). The results indicated that 44 and 51% of algal species tested showed cytotoxic and anti‐roliferative activity, respectively. Most of the cytotoxic extracts were species belong to Chlorophyta, Udotea flabellum and Udotea conglutinate showed the highest cytotoxic activity on all cancer cell lines. For Rhodophyta, the extract of Bryothamnion triquetrum showed an outstanding selective cytotoxicity against Hep‐2 cells (CC50 8.29 µg mL−1 with SI=12.04). Two out of five species of Phaeophyta tested (Lobophora variegata and Dictyota caribaea) showed high cytotoxicity activity on KB cell line. The data show that these extracts are potential source of compounds for prevention of certain cancer diseases. Citation Information: Cancer Prev Res 2010;3(1 Suppl):B78.
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In vitro cytotoxic and antiproliferative activities of marine macroalgae from Yucatán, Mexico
Ciencias Marinas, 2009Co-Authors: Rosa Moo-puc, Daniel Robledo, Yolanda Freile-pelegrínAbstract:Extracts from 27 marine algal species (14 Rhodophyta, 5 Phaeophyta, and 8 Chlorophyta) from the Yucatan Peninsula (Mexico) were evaluated for cytotoxic and antiproliferative activity by 3(4,5-dimethylthiazole-2-yl)-2,5 diphenyltetrazolium bromide (MTT) and sulforhodamine B (SRB) assays, respectively. To determine the specificity of cytotoxic activity against tumor cells, the selective index (SI) was also calculated. The following cancer cell lines were employed: normal canine kidney (MDCK) cells, human laryngeal carcinoma (Hep-2) cells, human cervical adenocarcinoma (HeLa) cells, and human nasopharyngeal carcinoma (KB) cells. The results indicated that 44% and 51% of the algal species tested showed cytotoxic and antiproliferative activity, respectively. Most of the cytotoxic extracts were from species of Chlorophyta, with Udotea flabellum and U. conglutinate showing the highest cytotoxic activity against all the cancer cell lines. For Rhodophyta, the Bryothamnion triquetrum extract showed outstanding selective cytotoxicity against Hep-2 cells (CC50 8.29 μg mL–1, SI = 12.04). Two of the five species of Phaeophyta tested (Lobophora variegata and Dictyota caribaea) showed high cytotoxicity activity against the KB cell line. The data show that these species are a potential source of compounds for the treatment of certain cancer diseases. Los extractos de 27 especies de algas marinas (14 Rhodophyta, 5 Phaeophyta y 8 Chlorophyta) recolectadas en la peninsula de Yucatan (Mexico) fueron evaluados para probar su actividad citotoxica y antiproliferativa usando los ensayos de 3[4,5-dimetiltiazol-2-il]-2,5-bromuro de difeniltetrazolio (MTT) y sulforodamina B (SRB), respectivamente. Para determinar la especificidad de la actividad citotoxica en las celulas tumorales, el indice de selectividad (IS) fue tambien calculado. Para lo anterior fueron empleadas las siguientes lineas celulares: celulas normales de rinon caninino (MDCK), celulas de carcinoma humano laringeo (Hep-2), celulas de adenocarcinoma humano de la cervix (HeLa) y celulas de carcinoma humano nasoafaringeo (KB). Los resultados indicaron que 44% y 51% de las especies exhibieron actividad citotoxica y antiproliferativa, respectivamente. La mayoria de los extractos citotoxicos fueron de las especies pertenecientes a la division Chlorophyta, siendo Udotea flabellum y U. conglutinata las especies que mostraron la mayor actividad citotoxica selectiva sobre todas las lineas celulares tumorales. Para la division Rhodophyta, el extracto de Bryothamnion triquetrum tuvo una destacable citotoxicidad selectiva contra las celulas Hep-2 (CC50 8.29 μg mL–1 con SI = 12.04). Dos de las cinco especies de Phaeophyta probadas (Lobophora variegata y Dictyota caribaea) mostraron alta actividad citotoxica sobre la linea celular KB. Los resultados muestran que estos extractos son una fuente prometedora de compuestos para el tratamiento de algunos tipos de cancer.
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Evaluation of selected tropical seaweeds for in vitro anti-trichomonal activity.
Journal of ethnopharmacology, 2008Co-Authors: R. Moo-puc, Daniel Robledo, Yolanda Freile-pelegrínAbstract:Abstract Ethnopharmacological relevance Human parasitic infections are a serious problem in tropical and sub-tropical developing countries. Trichomoniasis, responsible for the annual infection of 180 million people, is a common sexually transmitted disease caused by the protozoan Trichomonas vaginalis . Traditionally seaweeds have been used in folk medicine by coastal people in Asia and the Caribbean to treat parasitic infections and are a valuable source of novel anti-trichomonals. Aim of the study In our search for therapeutical alternatives to anti-protozoal chemotherapy, we collected a selection of 25 tropical seaweeds (12 Rhodophyta, 5 Phaeophyta and 8 Chlorophyta) from the coast of Yucatan (Mexico) in order to undertake ethnopharmacological and chemotaxonomic investigations. Materials and methods Organic algal extracts were tested for their anti-trichomonal properties on the growth inhibition of Trichomonas vaginalis . The cytotoxicity of seaweed extracts on mammal cell lines was also assessed. Results The results indicated that 44% of the seaweeds studied had high to moderate anti-trichomonal activity. Lobophora variegata and Udotea conglutinata showed the maximal anti-trichomonal activity with IC 50 values of 1.39 and 1.66 μg/ml, respectively, with good selectivity. Conclusions Lobophora variegata and Udotea conglutinata demonstrated promising anti-trichomonal potential and have been selected for further bio-guided fractionation and isolation of active anti-trichomonal compounds.
Ballesteros Enric - One of the best experts on this subject based on the ideXlab platform.
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Estructura de una comunidad de Halimeda tuna (Chlorophyceae, Caulerpales) en aguas profundas del Mediterráneo noroccidental
'Editorial CSIC', 1991Co-Authors: Ballesteros EnricAbstract:A deep-water community dominated by Halimeda tuna and Mesophyllum lichenoides is described from the rocky bottoms of the North-Western Mediterranean. Other sciaphilic algae such as Udotea petiolata, some Peyssonnelia species and Lithophyllum expansum are also abundant. Algal biomass ranges between 1200 and 2100 g dw m-2 while percentage coverage ranges from 180 to 400%. The variations observed in algal coverage adequately describe the seasonal pattern of the community, which is characterized by a high development of erect algae in summer months and a low development in winter. The species richness, as well as both species and pattern diversity reach a maximum in summer. Summer's maximum irradiances and the low irradiances received between November and February seem to account for the seasonal pattern described above. Community structure and environmental factors affecting the deep-water Halimeda populations from the North Western Mediterranean are compared with those found in other deep-water seaweed communities from the Mediterranean and other seas. Finally, the phytosociological affinities between these Halimeda populations and the deep-water Mediterranean associations previously described is assessed.Se describe una comunidad dominada por Halimeda tuna y Mesophyllum lichenoides en los fondos rocosos profundos del Mediterráneo Noroccidental. Dichas especies coexisten con Udotea petiolata, diversas especies de Peyssonnelia y Lithophyllum expansum, como especies más aparentes. La biomasa algal oscila entre 1200 y 2100 g ps m-2 mientras que el porcentaje de recubrimiento varía entre el 180 y el 400 %. Las variaciones encontradas en el recubrimiento algal describen adecuadamente el comportamiento estacional de la comunidad, el cual se caracteriza por un elevado desarrollo del estrato erecto durante el verano. La riqueza específica y la diversidad son también elevadas en verano. La mayor disponibilidad de luz veraniega parece explicar este comportamiento. La estructura de la comunidad y los factores ambientales a los que está sometida se comparan con los descritos en otras comunidades profundas del Mediterráneo y otros mares. Finalmente, se discute la afinidad de estas poblaciones de Halimeda con las distintas asociaciones descritas en la zona circalitoral del Mediterráneo Occidental
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Estructura de una comunidad de Halimeda tuna (Chlorophyceae, Caulerpales) en aguas profundas del Mediterráneo noroccidental
'Editorial CSIC', 1991Co-Authors: Ballesteros EnricAbstract:17 páginas, 7 figuras, 6 tablas.[EN] A deep-water community dominated by Halimeda tuna and Mesophyllum lichenoides is described from the rocky bottoms of the North-Western Mediterranean. Other sciaphilic algae such as Udotea petiolata, some Peyssonnelia species and Lithophyllum expansum are also abundant. Algal biomass ranges between 1200 and 2100 g dw m-2 while percentage coverage ranges from 180 to 400%. The variations observed in algal coverage adequately describe the seasonal pattern of the community, which is characterized by a high development of erect algae in summer months and a low development in winter. The species richness, as well as both species and pattern diversity reach a maximum in summer. Summer's maximum irradiances and the low irradiances received between November and February seem to account for the seasonal pattern described above. Community structure and environmental factors affecting the deep-water Halimeda populations from the North Western Mediterranean are compared with those found in other deep-water seaweed communities from the Mediterranean and other seas. Finally, the phytosociological affinities between these Halimeda populations and the deep-water Mediterranean associations previously described is assessed.[ES] Se describe una comunidad dominada por Halimeda tuna y Mesophyllum lichenoides en los fondos rocosos profundos del Mediterráneo Noroccidental. Dichas especies coexisten con Udotea petiolata, diversas especies de Peyssonnelia y Lithophyllum expansum, como especies más aparentes. La biomasa algal oscila entre 1200 y 2100 g ps m-2 mientras que el porcentaje de recubrimiento varía entre el 180 y el 400 %. Las variaciones encontradas en el recubrimiento algal describen adecuadamente el comportamiento estacional de la comunidad, el cual se caracteriza por un elevado desarrollo del estrato erecto durante el verano. La riqueza específica y la diversidad son también elevadas en verano. La mayor disponibilidad de luz veraniega parece explicar este comportamiento. La estructura de la comunidad y los factores ambientales a los que está sometida se comparan con los descritos en otras comunidades profundas del Mediterráneo y otros mares. Finalmente, se discute la afinidad de estas poblaciones de Halimeda con las distintas asociaciones descritas en la zona circalitoral del Mediterráneo Occidental.Peer reviewe
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Structure of a deep-water community of <i>Halimeda tuna</i> (<i>Chlorophyceae, Caulerpales)</i> from the North-Western Mediterranean
Consejo Superior de Investigaciones Científicas, 1991Co-Authors: Ballesteros EnricAbstract:A deep-water community dominated by <i>Halimeda tuna</i> and <i>Mesophyllum lichenoides</i> is described from the rocky bottoms of the North-Western Mediterranean. Other sciaphilic algae such as <i>Udotea petiolata</i>, some <i>Peyssonnelia</i> species and <i>Lithophyllum expansum</i> are also abundant. Algal biomass ranges between 1200 and 2100 g dw m<sup>-2</sup> while percentage coverage ranges from 180 to 400%. The variations observed in algal coverage adequately describe the seasonal pattern of the community, which is characterized by a high development of erect algae in summer months and a low development in winter. The species richness, as well as both species and pattern diversity reach a maximum in summer. Summer's maximum irradiances and the low irradiances received between November and February seem to account for the seasonal pattern described above. Community structure and environmental factors affecting the deep-water <i>Halimeda</i> populations from the North Western Mediterranean are compared with those found in other deep-water seaweed communities from the Mediterranean and other seas. Finally, the phytosociological affinities between these <i>Halimeda</i> populations and the deep-water Mediterranean associations previously described is assessed.<br><br>Se describe una comunidad dominada por <i><i>Halimeda</i> tuna</i> y <i>Mesophyllum lichenoides</i> en los fondos rocosos profundos del Mediterráneo Noroccidental. Dichas especies coexisten con <i>Udotea petiolata</i>, diversas especies de <i>Peyssonnelia</i> y <i>Lithophyllum expansum</i>, como especies más aparentes. La biomasa algal oscila entre 1200 y 2100 g ps m<sup>-2</sup> mientras que el porcentaje de recubrimiento varía entre el 180 y el 400 %. Las variaciones encontradas en el recubrimiento algal describen adecuadamente el comportamiento estacional de la comunidad, el cual se caracteriza por un elevado desarrollo del estrato erecto durante el verano. La riqueza específica y la diversidad son también elevadas en verano. La mayor disponibilidad de luz veraniega parece explicar este comportamiento. La estructura de la comunidad y los factores ambientales a los que está sometida se comparan con los descritos en otras comunidades profundas del Mediterráneo y otros mares. Finalmente, se discute la afinidad de estas poblaciones de <i>Halimeda</i> con las distintas asociaciones descritas en la zona circalitoral del Mediterráneo Occidental
Maxsuell Lucas Mendes Marques - One of the best experts on this subject based on the ideXlab platform.
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Anti-Thrombin, Anti-Adhesive, Anti-Migratory, and Anti-Proliferative Activities of Sulfated Galactans From the Tropical Green Seaweed, Udotea flabellum
Marine drugs, 2018Co-Authors: Maxsuell Lucas Mendes Marques, Fernando Bastos Presa, Rony Lucas Silva Viana, Leandro Silva Costa, Mariana Santana Santos Pereira Costa, Monica Oliveira Rocha Amorim, D. L. Bellan, M. Alves, Edvaldo S. Trindade, Hugo Alexandre Oliveira RochaAbstract:In this study, sulfated polysaccharide-rich extracts were isolated from 22 tropical seaweeds (4 red, 11 brown, and 7 green) found in northeastern Brazil, and evaluated for the role of anticoagulant agents. Fifteen of the extracts showed anticoagulant activity, including all the extracts from green seaweeds. Udotea flabellum (a green seaweed) extract was the most potent, requiring an amount of only 3 µg to double the plasma coagulation time in the activated partial thromboplastin time test. A similar result was obtained with 1 µg of heparin. Two sulfated homogalactans with anticoagulant activity, F-I (130 kDa) and F-II (75 kDa), were isolated from this extract using several bio-guided purification steps. Their anticoagulant activity, as well as properties related to antitumor activity (anti-proliferative, anti-adhesive, and anti-migratory), were accessed. Their anticoagulant activities were close to that of heparin. We found that F-I and F-II (0.5–10 μg/mL) were not able to directly inhibit thrombin. In the presence of anti-thrombin, F-I (0.5 μg/mL) was more effective than heparin (0.5 μg/mL) in inhibiting thrombin, while F-II showed similar effects as heparin. F-I and F-II also inhibited B16-F10 (murine melanoma cells) adhesion, migration, and proliferation on a fibronectin-coated surface, but not on laminin- or collagen I-coated surfaces. Except for the antiproliferative activity, the other effects of F-I and F-II were eliminated upon their desulfation (~50%), indicating that the degree of sulfation is not as important for F-I and F-II anti-proliferative activity as the sulfation position. Taken together, the results provide strong evidence for the potential utility of sulfated galactans from U. flabellum, making these compounds an interesting option for future investigations that aim to design new anticoagulant/antitumor agents.
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The Protective Role of Sulfated Polysaccharides from Green Seaweed Udotea flabellum in Cells Exposed to Oxidative Damage.
Marine drugs, 2018Co-Authors: Fernando Bastos Presa, Maxsuell Lucas Mendes Marques, Rony Lucas Silva Viana, Leonardo Thiago Duarte Barreto Nobre, Leandro Silva Costa, Hugo Alexandre Oliveira RochaAbstract:Seaweed is a rich source of bioactive sulfated polysaccharides. We obtained six sulfated polysaccharide-rich fractions (UF-0.3, UF-0.5, UF-0.6, UF-0.7, UF-1.0, and UF-2.0) from the green seaweed Udotea flabellum (UF) by proteolytic digestion followed by sequential acetone precipitation. Biochemical analysis of these fractions showed that they were enriched with sulfated galactans. The viability and proliferative capacity of 3T3 fibroblasts exposed to FeSO4 (2 µM), CuSO4 (1 µM) or ascorbate (2 mM) was not affected. However, these cells were exposed to oxidative stress in the presence of FeSO4 or CuSO4 and ascorbate, which caused the activation of caspase-3 and caspase-9, resulting in apoptosis of the cells. We also observed increased lipid peroxidation, evaluated by the detection of malondialdehyde and decreased glutathione and superoxide dismutase levels. Treating the cells with the ultrafiltrate fractions (UF) fractions protected the cells from the oxidative damage caused by the two salts and ascorbate. The most effective protection against the oxidative damage caused by iron was provided by UF-0.7 (1.0 mg/mL); on treatment with UF-0.7, cell viability was 55%. In the case of copper, cell viability on treatment with UF-0.7 was ~80%, but the most effective fraction in this model was UF-2.0, with cell viability of more than 90%. The fractions, mainly UF-0.7 and UF-2.0, showed low iron chelating activity, but high copper chelating activity and total antioxidant capacity (TAC). These results suggested that some of their protective mechanisms stem from these properties.
