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Brown algae ..as a protection mechanism against the heavy metal toxicity

Brown algae overproduce cell wall polysaccharides as a protection mechanism against the heavy metal toxicity

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  1. Brown algae overproduce cell wall polysaccharides as a protection mechanism against the heavy metal toxicity

    International Nuclear Information System (INIS)

     

     

    Brown algae are often used as heavy metal biomonitors and biosorbents because they can accumulate high concentrations of metals. Cation-exchange performed by cell wall polysaccharides is pointed out as the main chemical mechanism for the metal sequestration. Here, we biochemically investigated if the brown alga Padina gymnospora living in a heavy metal contaminated area would modify their polysaccharidic content. We exposed non-living biomass to Cd and Pb and studied the metals adsorption and localization. We found that raw dried polysaccharides, sulfate groups, uronic acids, fucose, mannose, and galactose were significantly higher in contaminated algae compared with the control ones. Metal concentrations adsorbed by non-living biomass were rising comparatively to the tested concentrations. Electron microscopy showed numerous granules in the cell walls and X-ray microanalysis revealed Cd as the main element. We concluded that P. gymnospora overproduces cell wall polysaccharides when exposed to high metal concentrations as a defense mechanism.

 

  1. Diterpenes from marine brown alga Dictyota guineensis (Dictyotaceae, Phaeophyceae)

    Scientific Electronic Library Online (English)

    Joel Campos, De-Paula; Diana Negrão, Cavalcanti; Yocie, Yoneshigue-Valentin; Valéria Laneuville, Teixeira.

    2012-08-01

    Full Text Available 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.

  2. Dolabelladienols A–C, New Diterpenes Isolated from Brazilian Brown Alga Dictyota pfaffii

    Directory of Open Access Journals (Sweden)

    Alonso Pardo-Vargas

    2014-07-01

    Full Text Available The marine brown alga Dictyota pfaffii from Atol das Rocas, in Northeast Brazil is a rich source of dolabellane diterpene, which has the potential to be used in future antiviral drugs by inhibiting reverse transcriptase (RT of HIV-1. Reexamination of the minor diterpene constituents yielded three new dolabellane diterpenes, (1R*,2E,4R*,7S,10S*,11S*,12R*10,18-diacetoxy-7-hydroxy-2,8(17-dolabelladiene (1, (1R*,2E,4R*,7R*,10S*,11S*,12R*10,18-diacetoxy-7-hydroxy-2,8(17-dolabelladiene (2, (1R*,2E,4R*,8E,10S*,11S,12R*10,18-diacetoxy-7-hydroxy-2,8-dolabelladiene (3, termed dolabelladienols A–C (1–3 respectively, in addition to the known dolabellane diterpenes (4–6. The elucidation of the compounds 1–3 was assigned by 1D and 2D NMR, MS, optical rotation and molecular modeling, along with the relative configuration of compound 4 and the absolute configuration of 5 by X-ray diffraction. The potent anti-HIV-1 activities displayed by compounds 1 and 2 (IC50 = 2.9 and 4.1 ?M, which were more active than even the known dolabelladienetriol 4, and the low cytotoxic activity against MT-2 lymphocyte tumor cells indicated that these compounds are promising anti-HIV-1 agents.

  3. Componentes diterpénicos del alga parda Dictyota sp.

    OpenAIRE

    Gonza?lez, Antonio G.; Marti?n, Julio D.; Pe?rez, Cirilo; Rovirosa, Juana

    1982-01-01

    Las algas pardas (Phaeophyta) de familia Dictyotaceae son habitantes comunes de las aguas superficiales, particularmente en zonas subtropicales y tropicales. Dichas algasparecen ser una fuente rica e interesante de metabolitos secundarios, generalmente compuestos diterpénicos. Hasta ahora todos los diterpenos bicíclicos no halogenados obtenidos de las algas han sido aislados de la familia Dictyotaceae, principalmente de la especie Dictyota.

  4. Evaluation of the acute toxicity of dolabelladienotriol, a potential antiviral from the brown alga Dictyota pfaffii, in BALB/c mice

    Scientific Electronic Library Online (English)

    Valéria, Garrido; Gerlinde A. P. B., Teixeira; Valéria L., Teixeira; Patrícia, Ocampo; Wilton J., Ferreira; Diana N., Cavalcanti; Sylvia M. N., Campos; Monique de M. B., Pedruzzi; Patricia, Olaya; Claudio C. C.dos, Santos; Viveca, Giongo; Izabel C. P., Paixão.

    2011-04-01

    Full Text Available Dolabelladienotriol is a product extracted from the brown marine alga Dictyota pfaffii from Brazil that has been shown to have antiviral activity and low cytotoxicity. Our studies have evaluated the acute toxicity of dolabelladienotriol in BALB/c mice for ten days after administration of a single do [...] se. Among the parameters considered were behavior, weight, biochemical and histological analyses of blood samples taken at three different times (Bs.0, Bs.1 and Bs.2) and optical microscopic examination of organs like liver, kidney, stomach and small intestine. Mice deaths were not observed at any dose during the ten day period. There were some changes in the biochemical analysis results for urea nitrogen (BUN) and alanine aminotransferase (ALT), but the changes were not significantly different from the reference levels of the animals before administration of the substance. Histological analyses of tissues were very similar for all animals. The alterations in liver and kidney tissues did not affect the animals´ behavior at any concentration, not even at 50 mg/kg, where the most significant changes in tissues were seen. This study indicates that dolabelladienotriol has low toxicity in administered dose range.

  5. Methanolic Extracts from Brown Seaweeds Dictyota cilliolata and Dictyota menstrualis Induce Apoptosis in Human Cervical Adenocarcinoma HeLa Cells

    Directory of Open Access Journals (Sweden)

    Dayanne Lopes Gomes

    2015-04-01

    Full Text Available Carcinoma of the uterine cervix is the second most common female tumor worldwide, surpassed only by breast cancer. Natural products from seaweeds evidencing apoptotic activity have attracted a great deal of attention as new leads for alternative and complementary preventive or therapeutic anticancer agents. Here, methanol extracts from 13 species of tropical seaweeds (Rhodophytas, Phaeophyta and Chlorophyta collected from the Northeast of Brazil were assessed as apoptosis-inducing agents on human cervical adenocarcinoma (HeLa. All extracts showed different levels of cytotoxicity against HeLa cells; the most potent were obtained from the brown alga Dictyotacilliolata (MEDC and Dictyota menstrualis (MEDM. In addition, MEDC and MEDM also inhibits SiHa (cervix carcinoma cell proliferation. Studies with these two extracts using flow cytometry and fluorescence microscopy showed that HeLa cells exposed to MEDM and MEDC exhibit morphological and biochemical changes that characterize apoptosis as shown by loss of cell viability, chromatin condensation, phosphatidylserine externalization, and sub-G1 cell cycle phase accumulation, also MEDC induces cell cycle arrest in cell cycle phase S. Moreover, the activation of caspases 3 and 9 by these extracts suggests a mitochondria-dependent apoptosis route. However, other routes cannot be ruled out. Together, these results point out the methanol extracts of the brown algae D. mentrualis and D. cilliolata as potential sources of molecules with antitumor activity.

  6. Methanolic extracts from brown seaweeds Dictyota cilliolata and Dictyota menstrualis induce apoptosis in human cervical adenocarcinoma HeLa cells.

    Science.gov (United States)

    Gomes, Dayanne Lopes; Telles, Cinthia Beatrice Silva; Costa, Mariana Santana Santos Pereira; Almeida-Lima, Jailma; Costa, Leandro Silva; Keesen, Tatjana Souza Lima; Rocha, Hugo Alexandre Oliveira

    2015-01-01

    Carcinoma of the uterine cervix is the second most common female tumor worldwide, surpassed only by breast cancer. Natural products from seaweeds evidencing apoptotic activity have attracted a great deal of attention as new leads for alternative and complementary preventive or therapeutic anticancer agents. Here, methanol extracts from 13 species of tropical seaweeds (Rhodophytas, Phaeophyta and Chlorophyta) collected from the Northeast of Brazil were assessed as apoptosis-inducing agents on human cervical adenocarcinoma (HeLa). All extracts showed different levels of cytotoxicity against HeLa cells; the most potent were obtained from the brown alga Dictyota cilliolata (MEDC) andDictyota menstrualis (MEDM). In addition, MEDC and MEDM also inhibits SiHa (cervix carcinoma) cell proliferation. Studies with these two extracts using flow cytometry and fluorescence microscopy showed that HeLa cells exposed to MEDM and MEDC exhibit morphological and biochemical changes that characterize apoptosis as shown by loss of cell viability, chromatin condensation, phosphatidylserine externalization, and sub-G1 cell cycle phase accumulation, also MEDC induces cell cycle arrest in cell cycle phase S. Moreover, the activation of caspases 3 and 9 by these extracts suggests a mitochondria-dependent apoptosis route. However, other routes cannot be ruled out. Together, these results point out the methanol extracts of the brown algae D. mentrualis and D. cilliolata as potential sources of molecules with antitumor activity. PMID:25871374

  7. 21 CFR 184.1120 - Brown algae.

    Science.gov (United States)

     

    2010-04-01

    ...DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) DIRECT FOOD SUBSTANCES AFFIRMED...1120 Brown algae. (a) Brown algae are seaweeds of the species Analipus...

  8. Isolation of glycoproteins from brown algae.

    DEFF Research Database (Denmark)

    Surendraraj, Alagarsamy Institute of Food and Dairy Technology, India

     

    The present invention relates to a novel process for the isolation of unique anti-oxidative glycoproteins from the pH precipitated fractions of enzymatic extracts of brown algae. Two brown seaweeds viz, Fucus serratus and Fucus vesiculosus were hydrolysed by using 3 enzymes viz, Alcalase, Viscozyme and Termamyl and the glycoproteins were isolated from these enzyme extracts.

  9. A cytotoxic hydroperoxy sterol from the brown alga, Nizamuddinia zanardinii

    OpenAIRE

    Abdolhossein Rustaiyan; Shahla Jamili; Homa Hajimehdipoor; Soodabeh Saeidnia; Jamileh Firouzi; Maryam Hamzeloo Moghadam; Gohari, Ahmad R.

    2013-01-01

    Background:The marine environment is a unique source of bioactive natural products, of which Nizamuddinia zanardinii is an important brown algae distributed in Oman Sea. Literature revealed that there is no report on phytochemistry and pharmacology of this valuable algae.Methods:Bioguided fractionation of the methanolic extract of Nizamuddinia zanardinii, collected from Oman Sea, led to the isolation of a hydroperoxy sterol. Its structure was determined by analysis of the spectroscopic data a...

  10. Monoclonal Antibodies Directed to Fucoidan Preparations from Brown Algae

    Science.gov (United States)

    Torode, Thomas A.; Marcus, Susan E.; Jam, Murielle; Tonon, Thierry; Blackburn, Richard S.; Hervé, Cécile; Knox, J. Paul

    2015-01-01

    Cell walls of the brown algae contain a diverse range of polysaccharides with useful bioactivities. The precise structures of the sulfated fucan/fucoidan group of polysaccharides and their roles in generating cell wall architectures and cell properties are not known in detail. Four rat monoclonal antibodies, BAM1 to BAM4, directed to sulfated fucan preparations, have been generated and used to dissect the heterogeneity of brown algal cell wall polysaccharides. BAM1 and BAM4, respectively, bind to a non-sulfated epitope and a sulfated epitope present in the sulfated fucan preparations. BAM2 and BAM3 identified additional distinct epitopes present in the fucoidan preparations. All four epitopes, not yet fully characterised, occur widely within the major brown algal taxonomic groups and show divergent distribution patterns in tissues. The analysis of cell wall extractions and fluorescence imaging reveal differences in the occurrence of the BAM1 to BAM4 epitopes in various tissues of Fucus vesiculosus. In Ectocarpus subulatus, a species closely related to the brown algal model Ectocarpus siliculosus, the BAM4 sulfated epitope was modulated in relation to salinity levels. This new set of monoclonal antibodies will be useful for the dissection of the highly complex and yet poorly resolved sulfated polysaccharides in the brown algae in relation to their ecological and economic significance. PMID:25692870

  11. Biosynthetic Pathway and Health Benefits of Fucoxanthin, an Algae-Specific Xanthophyll in Brown Seaweeds

    OpenAIRE

    Masashi Hosokawa; Koji Mikami

    2013-01-01

    Fucoxanthin is the main carotenoid produced in brown algae as a component of the light-harvesting complex for photosynthesis and photoprotection. In contrast to the complete elucidation of the carotenoid biosynthetic pathways in red and green algae, the biosynthetic pathway of fucoxanthin in brown algae is not fully understood. Recently, two models for the fucoxanthin biosynthetic pathway have been proposed in unicellular diatoms; however, there is no such information for the pathway in brown...

  12. Pachydictyols B and C: New Diterpenes from Dictyota dichotoma Hudson

    Directory of Open Access Journals (Sweden)

    Hartmut Laatsch

    2013-08-01

    Full Text Available Two new diterpenoids, pachydictyol B (1a/1b and C (2, were isolated from the dichloromethane extract of the marine brown algaDictyota dichotoma, collected from the Red Sea coast of Egypt, along with the known metabolites, pachydictyol A (3a, dictyol E (4, cis-africanan-1?-ol (5a, fucosterol (6, tetrahydrothiophen-1,1-dioxide and poly-?-hydroxybutyric acid. GC-MS analysis of the nonpolar fractions also indicated the presence of ?-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 (IC50 = 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 IC50 of >30.0 µM.

  13. A Cytotoxic Hydroperoxy Sterol from the Brown Alga, Nizamuddinia Zanardinii

    Directory of Open Access Journals (Sweden)

    Abdolhossein Rustaiyan

    2013-03-01

    Full Text Available Background:The marine environment is a unique source of bioactive natural products, of which Nizamuddinia zanardinii is an important brown algaedistributed in Oman Sea. Literature revealed that there is no report on phytochemistry and pharmacology of this valuable algae.Methods:Bioguided fractionation of the methanolic extract of Nizamuddinia zanardinii, collected from Oman Sea, led to the isolation of a hydroperoxy sterol. Its structure was determined by analysis of the spectroscopic data as 24-hydroperoxy-24-vinyl cholesterol (HVC. In vitro cytotoxic activity of this compound was evaluated against HT29, MCF7, A549, HepG2 and MDBK cell lines.Results:Although 24(R-hydroproxy-24-vinylcholesterol has been previously reported from Sargassum and Padina species, it is the first report on the presence of this compound from N. zanardinii. This compound exhibited cytotoxicity in all cell lines (IC50, 3.62, 9.09, 17.96, 32.31 and 37.31??g/mL respectively. HVC was also evaluated for apoptotic activity and demonstrated positive results in terminal deoxynucleotidyl transferase dUTP Nick End labeling (TUNEL assay suggesting it a candidate for further apoptotic studies.Conclusions:Nizamuddinia zanardinii, a remarkable brown algae of Oman Sea, is a good source of hydroproxy sterols with promising cytotoxic on various cell lines particularly human colon adenocarcinoma.

  14. Fucoidan from Marine Brown Algae Inhibits Lipid Accumulation

    OpenAIRE

    Changhyun Roh; Min-Kyoung Park; Uhee Jung

    2011-01-01

    In this study, we elucidated the inhibitory effect of fucoidan from marine brown algae on the lipid accumulation in differentiated 3T3-L1 adipocytes and its mechanism. The treatment of fucoidan in a dose-dependent manner was examined on lipid inhibition in 3T3-L1 cells by using Oil Red O staining. Fucoidan showed high lipid inhibition activity at 200 µg/mL concentration (P < 0.001). Lipolytic activity in adipocytes is highly dependent on hormone sensitive lipase (HSL), which is one of the...

  15. Fucoxanthin and Its Metabolites in Edible Brown Algae Cultiva

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