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John A. West - One of the best experts on this subject based on the ideXlab platform.
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calcium oxalate crystals in the marine red alga spyridia filamentosa Ceramiales rhodophyta
Phycologia, 2007Co-Authors: Curt M. Pueschel, John A. WestAbstract:Birefringent polyhedral crystals up to 8 mm on a side were found both within cells and on the thallus surfaces of several genetically distinct isolates of the red alga Spyridia filamentosa (Wulfen) Harvey. Diagnostic chemical solubility tests and silver nitrate–dithiooxamide staining identified the crystals as calcium oxalate. Calcium oxalate crystals were observed in all cell types of the vegetative erect axes: axial cells of indeterminate filaments, corticating cells of the main axes, and axial and corticating cells of the determinate lateral filaments (brachyblasts). Thalli cultured in natural seawater medium had few crystals close to the growing apices, whereas older portions of the thalli developed a surface coating of fine crystals and scattered larger extracellular and intracellular crystals. Thalli cultured in natural seawater medium whose calcium concentration was supplemented with 20 mM calcium chloride had an abundance of intracellular and extracellular calcium oxalate crystals. Thalli grown in artificial seawater medium having low calcium concentrations (1.0 and 2.5 mM calcium chloride) deposited few calcium oxalate crystals, but when these thalli were transferred to calcium-rich medium and stressed, crystals formed rapidly. The nonconstitutive nature of calcium oxalate deposition in Spyridia may explain conflicting previous accounts regarding presence of calcium oxalate crystals in this genus.
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Floridoside in the genus Laurencia (Rhodomelaceae: Ceramiales) – a chemosystematic study
Phycologia, 1995Co-Authors: Kevin D Barrow, Robert King, Ulf Karsten, John A. WestAbstract:Abstract The heteroside floridoside has been recorded in 21 specimens of Laurencia, as well as in some closely related species: Osmundea hybrida (A.P. de Candolie) Nam, a. pinnatifida (Hudson) Stackhouse, a. spectabilis (Postels et Ruprecht) Nam, O. truncata (Kutzing) Nam et Maggs and Chondria capensis (Harvey) Askenasy (Rhodomelaceae, Ceramiales). The occurrence of this carbohydrate in the Ceramiales negates the proposition that the presence of floridoside is a chemotaxonomic marker only for orders of the Rhodophyta other than the Ceramiales. Digeneaside, which is known as a characteristic photo-assimilatory product only in representatives of the Ceramiales, was not detected in any of the species investigated, including five species in which it was previously detected; its previously proposed high diagnostic value is negated and its reported occurrence in these species is questioned.
Alison R. Sherwood - One of the best experts on this subject based on the ideXlab platform.
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molecular and morphological variation of the red alga spyridia filamentosa Ceramiales rhodophyta in the hawaiian archipelago
Phycologia, 2012Co-Authors: Kimberly Y Conklin, Alison R. SherwoodAbstract:Conklin K.Y. and Sherwood A.R. 2012. Molecular and morphological variation of the red alga Spyridia filamentosa (Ceramiales, Rhodophyta) in the Hawaiian Archipelago. Phycologia 51: 347–357. DOI: 10.2216/10-26.1 Genetic information is proving to be important in conservation and management efforts that involve cryptic species and their role in native ecosystem restoration. Previous molecular studies have demonstrated that the red alga Spyridia filamentosa consists of several cryptic species. Spyridia filamentosa is considered to be a native species in Hawai‘i and was recently used in preliminary seagrass meadow restoration efforts in Maunalua Bay, O‘ahu. It became necessary to understand the genetic diversity of this species in the Islands and determine if there are relationships between any molecular clades of S. filamentosa and anatomical characters that might be useful (e.g. sediment capture) in habitat remediation. Both molecular and morphological (determinate branch cell dimensions) analyses revealed t...
Nathalie Bourgougnon - One of the best experts on this subject based on the ideXlab platform.
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Antiviral activities of sulfated polysaccharides isolated from Sphaerococcus coronopifolius (Rhodophytha, Gigartinales) and Boergeseniella thuyoides (Rhodophyta, Ceramiales).
Marine drugs, 2011Co-Authors: Rhimou Bouhlal, Jean-claude Chermann, Camille Haslin, Sylvia Colliec-jouault, Corinne Sinquin, Gaëlle Simon, Stéphane Cérantola, Hassane Riadi, Nathalie BourgougnonAbstract:Water-soluble sulfated polysaccharides isolated from two red algae Sphaerococcus coronopifolius (Gigartinales, Sphaerococcaceae) and Boergeseniella thuyoides (Ceramiales, Rhodomelaceae) collected on the coast of Morocco inhibited in vitro replication of the Human Immunodeficiency Virus (HIV) at 12.5 µg/mL. In addition, polysaccharides were capable of inhibiting the in vitro replication of Herpes simplex virus type 1 (HSV-1) on Vero cells values of EC50 of 4.1 and 17.2 µg/mL, respectively. The adsorption step of HSV-1 to the host cell seems to be the specific target for polysaccharide action. While for HIV-1, these results suggest a direct inhibitory
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Antiviral activities of sulfated polysaccharides isolated from Sphaerococcus coronopifolius (Rhodophytha, Gigartinales) and Boergeseniella thuyoides (Rhodophyta, Ceramiales).
Marine drugs, 2011Co-Authors: Rhimou Bouhlal, Jean-claude Chermann, Camille Haslin, Sylvia Colliec-jouault, Corinne Sinquin, Gaëlle Simon, Stéphane Cérantola, Hassane Riadi, Nathalie BourgougnonAbstract:Water-soluble sulfated polysaccharides isolated from two red algae Sphaerococcus coronopifolius (Gigartinales, Sphaerococcaceae) and Boergeseniella thuyoides (Ceramiales, Rhodomelaceae) collected on the coast of Morocco inhibited in vitro replication of the Human Immunodeficiency Virus (HIV) at 12.5 μg/mL. In addition, polysaccharides were capable of inhibiting the in vitro replication of Herpes simplex virus type 1 (HSV-1) on Vero cells values of EC₅₀ of 4.1 and 17.2 μg/mL, respectively. The adsorption step of HSV-1 to the host cell seems to be the specific target for polysaccharide action. While for HIV-1, these results suggest a direct inhibitory effect on HIV-1 replication by controlling the appearance of the new generations of virus and potential virucidal effect. The polysaccharides from S. coronopifolius (PSC) and B. thuyoides (PBT) were composed of galactose, 3,6-anhydrogalactose, uronics acids, sulfate in ratios of 33.1, 11.0, 7.7 and 24.0% (w/w) and 25.4, 16.0, 3.2, 7.6% (w/w), respectively.
Kimberly Y Conklin - One of the best experts on this subject based on the ideXlab platform.
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molecular and morphological variation of the red alga spyridia filamentosa Ceramiales rhodophyta in the hawaiian archipelago
Phycologia, 2012Co-Authors: Kimberly Y Conklin, Alison R. SherwoodAbstract:Conklin K.Y. and Sherwood A.R. 2012. Molecular and morphological variation of the red alga Spyridia filamentosa (Ceramiales, Rhodophyta) in the Hawaiian Archipelago. Phycologia 51: 347–357. DOI: 10.2216/10-26.1 Genetic information is proving to be important in conservation and management efforts that involve cryptic species and their role in native ecosystem restoration. Previous molecular studies have demonstrated that the red alga Spyridia filamentosa consists of several cryptic species. Spyridia filamentosa is considered to be a native species in Hawai‘i and was recently used in preliminary seagrass meadow restoration efforts in Maunalua Bay, O‘ahu. It became necessary to understand the genetic diversity of this species in the Islands and determine if there are relationships between any molecular clades of S. filamentosa and anatomical characters that might be useful (e.g. sediment capture) in habitat remediation. Both molecular and morphological (determinate branch cell dimensions) analyses revealed t...
Cesira Perrone - One of the best experts on this subject based on the ideXlab platform.
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growth pattern assessment in the genus acanthophora rhodophyta Ceramiales
Phycologia, 2006Co-Authors: Cesira Perrone, Ester Cecere, Giovanni FurnariAbstract:C. PERRONE ,E . C ECERE AND G. FURNARI. 2006. Growth pattern assessment in the genus Acanthophora (Rhodophyta, Ceramiales). Phycologia 45: 37‐43. DOI: 10.2216/04-45.1 The results of a morphological study, mainly based on the growth pattern and shape of both apical zone and branch primordia of all the terete species of Acanthophora, are presented here. This study shows that species are mainly distinguished on the basis of developmental features such as monopodial vs sympodial growth pattern and not by characters such as the presence or absence of spines on the main axes and the morphology of the stichidial ramuli previously generally used to distinguish the species of this genus, and which have proved to be of no diagnostic value. A key to the species of Acanthophora based on both the results of the present research and easily detectable characters is also proposed. K EY WORDS: Acanthophora, Acanthophora aokii, Acanthophora dendroides, Acanthophora muscoides, Acanthophora nayadiformis, Acanthophora ramulosa, Acanthophora spicifera, taxonomy
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Developmental morphology of Acanthophora nayadiformis (Rhodophyta, Ceramiales): Sympodial growth and propagule germination
Plant Biosystems - An International Journal Dealing with all Aspects of Plant Biology, 2005Co-Authors: Cesira Perrone, E. Cecere, C. I. Delle FoglieAbstract:Abstract The A. nayadiformis thallus is peculiar due both to its morphological organization and to the production of specialized vegetative propagules resembling turions of aquatic dicotyledons. Propagules have proved to be useful culture inocula for morphogenetic research. They germinate quickly when cultured under optimal conditions, growing in a polar fashion, producing uprights from their distal buds and axes with rhizoids from the proximal ones. The thallus growth pattern in A. nayadiformis at first involves a monopodial arrangement of determinate branches followed by ramisympodial growth at all thallus levels with an unpredictable model. There is not, in fact, a fixed ‘sympodial unit’ which reiterates itself in the ramisympodia, thus giving rise to great morphological diversity. Both irradiance and temperature have a significant effect on propagule bud growth rate, but not on their developmental morphology. In contrast, changes in the apex morphogenetic trend, such as transformation from the stolon ...
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morphology of acanthophora nayadiformis Ceramiales rhodophyta
Phycologia, 2002Co-Authors: Ester Cecere, Cesira PerroneAbstract:Abstract Acanthophora nayadiformis is a perennial species of red alga that overwinters by means of a rhizomatous prostrate system; both reproductive and vegetative plants are also able to spread by means of specialized vegetative propagules that have never been reported in other Acanthophora species. A detailed study of thallus morphology has highlighted four kinds of primordia in this species, distinct in shape, size and origin, that develop into as many different types of branches. Thallus growth is at first monopodial, shifting to ramisympodial in most plants. Even the morphological variation observed among tetrasporiferous branches is caused by the type and development of their parent primordia, which confirms the extreme inadequacy of this feature for taxonomic or diagnostic use at species level.