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Ruth Falshaw - One of the best experts on this subject based on the ideXlab platform.
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Growth and carrageenan composition of two populations of the New Zealand carrageenophyte Sarcothalia lanceata (Gigartinaceae, Rhodophyta)
Journal of Applied Phycology, 2018Co-Authors: Kate Neill, Wendy Nelson, Catriona Hurd, Ruth FalshawAbstract:Sarcothalia lanceata is a broad-bladed, New Zealand red alga. The tetrasporic life stage contains a Lambda-Carrageenan that has a strong potential for commercial utilisation. The male and female gametophytic life stages contain kappa-II carrageenan that also has commercial potential. However, fundamental information on the growth and variation in carrageenan content of this species in the wild is necessary to underpin possible aquaculture of this species. Therefore, growth in blade length and width was assessed for male and female gametophytes, and tetrasporophytes in two S. lanceata populations in New Zealand’s South Island, and monthly seawater nutrient and tissue nutrients, and carrageenan constituent sugar levels were analysed. Blade length did not vary significantly over time or between life history phases; however, blade width varied significantly for both factors with most temporal variation occurring in male blades. Analysis of seawater and tissue nutrient levels suggested that these populations are nutrient limited year-round. Constituent sugars varied temporally and between life history phases in most cases. Relative 3,6-anhydrogalactitol peracetate (for the males and females) and galactitol peracetate levels (all life stages) were higher in winter than in summer, while glucitol peracetate and xylitol peracetate levels were generally lower in winter than summer. The distinctive morphologies of the male and female plants of this species mean there is potential to cultivate and then separately harvest male and female plants in addition to tetrasporophytic plants. Male blades contain more 3,6-anhydrogalactitol peracetate and galactitol peracetate than female blades, and their morphology may make them less prone to breakage in an aquaculture situation. Experimentation on spore release and growth and the potential effects of nutrient manipulation on early stages are suggested as the direction of future research.
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clump structure population structure and non destructive biomass estimation of the new zealand carrageenophyte sarcothalia lanceata gigartinaceae rhodophyta
Botanica Marina, 2016Co-Authors: Kate F Neill, Ruth Falshaw, Wendy A Nelson, Catriona L HurdAbstract:Sarcothalia lanceata is a New Zealand carrageenophyte with tetrasporophytic thalli that produce carrageenan very close to the idealised structure of Lambda-Carrageenan. As such there is interest in its potential for commercial utilisation. There is no information on the biology and ecology of natural populations of this species, but this knowledge is critical for determining whether a species is a suitable candidate for sustainable wild harvest or for aquaculture. Population studies were conducted at two sites in New Zealand’s South Island in order to provide fundamental information on this species. The structure (abundance and composition of male, female, tetrasporophytic and non-reproductive clumps) of the two populations was assessed monthly over a year, and population biomass estimated using regression methods. Seasonal variation was not evident in most of the parameters measured, but differences between sites were found in total population density, the density of different life-history phases, and clump size and structure. The turnover in biomass occurs more frequently at the blade level than at the clump level and the presence of a basal crust in this species promotes population stability.
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chemotaxonomy of new zealand red algae in the family gigartinaceae rhodophyta based on galactan structures from the tetrasporophyte life stage
Carbohydrate Research, 2009Co-Authors: Ruth Falshaw, Richard H FurneauxAbstract:The identification of the polysaccharides from tetrasporophytic plants of nine endemic New Zealand species belonging to the Gigartinaceae, 'Gigartina' ancistroclada, 'G.' grandifida, Gigartina dilatata, G. divaricata, G. macrocarpa, G. marginifera, G. pachymenioides, G. sp. 'Lindauer 164' and Sarcothalia livida using infra-red spectroscopy in conjunction with constituent sugar and glycosyl linkage/substitution analysis is reported. All nine species contain galactans with structures consistent with lambda-type carrageenans. Differences in the structures of the galactans in these and a further six previously studied species indicate chemotaxonomically distinct groupings that correspond to Sarcothalia, 'Sarcothalia' and Gigartina genera plus some outliers. These distinct, chemotaxonomic groupings are aligned to those determined by rbcL sequence analysis reported in the literature.
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carrageenan from the tetrasporic stage of gigartina decipiens gigartinaceae rhodophyta
Carbohydrate Research, 1994Co-Authors: Ruth Falshaw, Richard H FurneauxAbstract:The structure of the polysaccharide isolated from tetrasporophytic plants of the New Zealand red alga Gigartina decipiens has been determined by chemical and spectroscopic techniques. It is a linear polymer composed primarily of alternating 3-linked beta-D-galactopyranosyl 2-sulphate and 4-linked alpha-D-galactopyranosyl 2,6-disulphate residues. About 15% of the 3-linked residues have an additional sulphate ester group at the 6-position. Aside from this small extra sulphate substitution, the structure is that of the idealised Lambda-Carrageenan. Good quality solution-state 13C NMR spectra were recorded and interpreted for this carrageenan and for the carrageenans produced from it by solvolytic desulphation and alkali modification.
Gurvan Michel - One of the best experts on this subject based on the ideXlab platform.
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Evolutionary evidence of algal polysaccharide degradation acquisition by pseudoalteromonas carrageenovora 9(t) to adapt to macroalgal niches
Frontiers in Microbiology, 2018Co-Authors: Angélique Gobet, Tristan Barbeyron, Maria Matard-mann, Ghislaine Magdelenat, David Vallenet, Eric Duchaud, Gurvan MichelAbstract:About half of seaweed biomass is composed of polysaccharides. Most of these complex polymers have a marked polyanionic character. For instance, the red algal cell wall is mainly composed of sulfated galactans, agars and carrageenans, while brown algae contain alginate and fucose-containing sulfated polysaccharides (FCSP) as cell wall polysaccharides. Some marine heterotrophic bacteria have developed abilities to grow on such macroalgal polysaccharides. This is the case of Pseudoalteromonas carrageenovora 9(T) (ATCC 43555(T)), a marine gammaproteobacterium isolated in 1955 and which was an early model organism for studying carrageenan catabolism. We present here the genomic analysis of P. carrageenovora. Its genome is composed of two chromosomes and of a large plasmid encompassing 109 protein-coding genes. P. carrageenovora possesses a diverse repertoire of carbohydrate-active enzymes (CAZymes), notably specific for the degradation of macroalgal polysaccharides (laminarin, alginate, FCSP, carrageenans). We confirm these predicted capacities by screening the growth of P. carrageenovora with a large collection of carbohydrates. Most of these CAZyme genes constitute clusters located either in the large chromosome or in the small one. Unexpectedly, all the carrageenan catabolism-related genes are found in the plasmid, suggesting that P. carrageenovora acquired its hallmark capacity for carrageenan degradation by horizontal gene transfer (HGT). Whereas P. carrageenovora is able to use Lambda-Carrageenan as a sole carbon source, genomic and physiological analyses demonstrate that its catabolic pathway for kappa- and iota-carrageenan is incomplete. This is due to the absence of the recently discovered 3,6-anhydro-D-galactosidase genes (GH127 and GH129 families). A genomic comparison with 52 Pseudoalteromonas strains confirms that carrageenan catabolism has been recently acquired only in a few species. Even though the loci for cellulose biosynthesis and alginate utilization are located on the chromosomes, they were also horizontally acquired. However, these HGTs occurred earlier in the evolution of the Pseudoalteromonas genus, the cellulose- and alginate-related loci being essentially present in one large, late-diverging clade (LDC). Altogether, the capacities to degrade cell wall polysaccharides from macroalgae are not ancestral in the Pseudoalteromonas genus. Such catabolism in P. carrageenovora resulted from a succession of HGTs, likely allowing an adaptation to the life on the macroalgal surface.
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Table_4_Evolutionary Evidence of Algal Polysaccharide Degradation Acquisition by Pseudoalteromonas carrageenovora 9T to Adapt to Macroalgal Niches.XLSX
2018Co-Authors: Angélique Gobet, Tristan Barbeyron, Maria Matard-mann, Ghislaine Magdelenat, David Vallenet, Eric Duchaud, Gurvan MichelAbstract:About half of seaweed biomass is composed of polysaccharides. Most of these complex polymers have a marked polyanionic character. For instance, the red algal cell wall is mainly composed of sulfated galactans, agars and carrageenans, while brown algae contain alginate and fucose-containing sulfated polysaccharides (FCSP) as cell wall polysaccharides. Some marine heterotrophic bacteria have developed abilities to grow on such macroalgal polysaccharides. This is the case of Pseudoalteromonas carrageenovora 9T (ATCC 43555T), a marine gammaproteobacterium isolated in 1955 and which was an early model organism for studying carrageenan catabolism. We present here the genomic analysis of P. carrageenovora. Its genome is composed of two chromosomes and of a large plasmid encompassing 109 protein-coding genes. P. carrageenovora possesses a diverse repertoire of carbohydrate-active enzymes (CAZymes), notably specific for the degradation of macroalgal polysaccharides (laminarin, alginate, FCSP, carrageenans). We confirm these predicted capacities by screening the growth of P. carrageenovora with a large collection of carbohydrates. Most of these CAZyme genes constitute clusters located either in the large chromosome or in the small one. Unexpectedly, all the carrageenan catabolism-related genes are found in the plasmid, suggesting that P. carrageenovora acquired its hallmark capacity for carrageenan degradation by horizontal gene transfer (HGT). Whereas P. carrageenovora is able to use Lambda-Carrageenan as a sole carbon source, genomic and physiological analyses demonstrate that its catabolic pathway for kappa- and iota-carrageenan is incomplete. This is due to the absence of the recently discovered 3,6-anhydro-D-galactosidase genes (GH127 and GH129 families). A genomic comparison with 52 Pseudoalteromonas strains confirms that carrageenan catabolism has been recently acquired only in a few species. Even though the loci for cellulose biosynthesis and alginate utilization are located on the chromosomes, they were also horizontally acquired. However, these HGTs occurred earlier in the evolution of the Pseudoalteromonas genus, the cellulose- and alginate-related loci being essentially present in one large, late-diverging clade (LDC). Altogether, the capacities to degrade cell wall polysaccharides from macroalgae are not ancestral in the Pseudoalteromonas genus. Such catabolism in P. carrageenovora resulted from a succession of HGTs, likely allowing an adaptation to the life on the macroalgal surface.
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Data_Sheet_1_Evolutionary Evidence of Algal Polysaccharide Degradation Acquisition by Pseudoalteromonas carrageenovora 9T to Adapt to Macroalgal Niches.PDF
2018Co-Authors: Angélique Gobet, Tristan Barbeyron, Maria Matard-mann, Ghislaine Magdelenat, David Vallenet, Eric Duchaud, Gurvan MichelAbstract:About half of seaweed biomass is composed of polysaccharides. Most of these complex polymers have a marked polyanionic character. For instance, the red algal cell wall is mainly composed of sulfated galactans, agars and carrageenans, while brown algae contain alginate and fucose-containing sulfated polysaccharides (FCSP) as cell wall polysaccharides. Some marine heterotrophic bacteria have developed abilities to grow on such macroalgal polysaccharides. This is the case of Pseudoalteromonas carrageenovora 9T (ATCC 43555T), a marine gammaproteobacterium isolated in 1955 and which was an early model organism for studying carrageenan catabolism. We present here the genomic analysis of P. carrageenovora. Its genome is composed of two chromosomes and of a large plasmid encompassing 109 protein-coding genes. P. carrageenovora possesses a diverse repertoire of carbohydrate-active enzymes (CAZymes), notably specific for the degradation of macroalgal polysaccharides (laminarin, alginate, FCSP, carrageenans). We confirm these predicted capacities by screening the growth of P. carrageenovora with a large collection of carbohydrates. Most of these CAZyme genes constitute clusters located either in the large chromosome or in the small one. Unexpectedly, all the carrageenan catabolism-related genes are found in the plasmid, suggesting that P. carrageenovora acquired its hallmark capacity for carrageenan degradation by horizontal gene transfer (HGT). Whereas P. carrageenovora is able to use Lambda-Carrageenan as a sole carbon source, genomic and physiological analyses demonstrate that its catabolic pathway for kappa- and iota-carrageenan is incomplete. This is due to the absence of the recently discovered 3,6-anhydro-D-galactosidase genes (GH127 and GH129 families). A genomic comparison with 52 Pseudoalteromonas strains confirms that carrageenan catabolism has been recently acquired only in a few species. Even though the loci for cellulose biosynthesis and alginate utilization are located on the chromosomes, they were also horizontally acquired. However, these HGTs occurred earlier in the evolution of the Pseudoalteromonas genus, the cellulose- and alginate-related loci being essentially present in one large, late-diverging clade (LDC). Altogether, the capacities to degrade cell wall polysaccharides from macroalgae are not ancestral in the Pseudoalteromonas genus. Such catabolism in P. carrageenovora resulted from a succession of HGTs, likely allowing an adaptation to the life on the macroalgal surface.
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Image_1_Evolutionary Evidence of Algal Polysaccharide Degradation Acquisition by Pseudoalteromonas carrageenovora 9T to Adapt to Macroalgal Niches.PDF
2018Co-Authors: Angélique Gobet, Tristan Barbeyron, Maria Matard-mann, Ghislaine Magdelenat, David Vallenet, Eric Duchaud, Gurvan MichelAbstract:About half of seaweed biomass is composed of polysaccharides. Most of these complex polymers have a marked polyanionic character. For instance, the red algal cell wall is mainly composed of sulfated galactans, agars and carrageenans, while brown algae contain alginate and fucose-containing sulfated polysaccharides (FCSP) as cell wall polysaccharides. Some marine heterotrophic bacteria have developed abilities to grow on such macroalgal polysaccharides. This is the case of Pseudoalteromonas carrageenovora 9T (ATCC 43555T), a marine gammaproteobacterium isolated in 1955 and which was an early model organism for studying carrageenan catabolism. We present here the genomic analysis of P. carrageenovora. Its genome is composed of two chromosomes and of a large plasmid encompassing 109 protein-coding genes. P. carrageenovora possesses a diverse repertoire of carbohydrate-active enzymes (CAZymes), notably specific for the degradation of macroalgal polysaccharides (laminarin, alginate, FCSP, carrageenans). We confirm these predicted capacities by screening the growth of P. carrageenovora with a large collection of carbohydrates. Most of these CAZyme genes constitute clusters located either in the large chromosome or in the small one. Unexpectedly, all the carrageenan catabolism-related genes are found in the plasmid, suggesting that P. carrageenovora acquired its hallmark capacity for carrageenan degradation by horizontal gene transfer (HGT). Whereas P. carrageenovora is able to use Lambda-Carrageenan as a sole carbon source, genomic and physiological analyses demonstrate that its catabolic pathway for kappa- and iota-carrageenan is incomplete. This is due to the absence of the recently discovered 3,6-anhydro-D-galactosidase genes (GH127 and GH129 families). A genomic comparison with 52 Pseudoalteromonas strains confirms that carrageenan catabolism has been recently acquired only in a few species. Even though the loci for cellulose biosynthesis and alginate utilization are located on the chromosomes, they were also horizontally acquired. However, these HGTs occurred earlier in the evolution of the Pseudoalteromonas genus, the cellulose- and alginate-related loci being essentially present in one large, late-diverging clade (LDC). Altogether, the capacities to degrade cell wall polysaccharides from macroalgae are not ancestral in the Pseudoalteromonas genus. Such catabolism in P. carrageenovora resulted from a succession of HGTs, likely allowing an adaptation to the life on the macroalgal surface.
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degradation of lambda carrageenan by pseudoalteromonas carrageenovora lambda carrageenase a new family of glycoside hydrolases unrelated to kappa and iota carrageenases
Biochemical Journal, 2007Co-Authors: Marion Guibet, Sébastien Colin, Gurvan Michel, Bernard Kloareg, Tristan Barbeyron, Sabine Genicot, William HelbertAbstract:Carrageenans are sulfated galactans found in the cell walls of red seaweeds. They are classified according to the number and the position of sulfate ester groups. Lambda-Carrageenan is the most sulfated carrageenan and carries at least three sulfates per disaccharide unit. The sole known depolymerizing enzyme of Lambda-Carrageenan, the lambda-carrageenase from Pseudoalteromonas carrageenovora, has been purified, cloned and sequenced. Sequence analyses have revealed that the lambda-carrageenase, referred to as CglA, is the first member of a new family of GHs (glycoside hydrolases), which is unrelated to families GH16, that contains kappa-carrageenases, and GH82, that contains iota-carrageenases. This large enzyme (105 kDa) features a low-complexity region, suggesting the presence of a linker connecting at least two independent modules. The N-terminal region is predicted to fold as a beta-propeller. The main degradation products have been purified and characterized as neo-lambda-carratetraose [DP (degree of polymerization) 4] and neo-lambda-carrahexaose (DP6), indicating that CglA hydrolyses the beta-(1-->4) linkage of Lambda-Carrageenan. LC-MALLS (liquid chromatography-multi-angle laser light scattering) and (1)H-NMR monitoring of the enzymatic degradation of Lambda-Carrageenan indicate that CglA proceeds according to an endolytic mode of action and a mechanism of inversion of the anomeric configuration. Using 2-aminoacridone-labelled neo-lambda-carrabiose oligosaccharides, in the present study we demonstrate that the active site of CglA comprises at least 8 subsites (-4 to +4) and that a DP6 oligosaccharide binds in the subsites -4 to +2 and can be hydrolysed into DP4 and DP2.
Richard H Furneaux - One of the best experts on this subject based on the ideXlab platform.
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chemotaxonomy of new zealand red algae in the family gigartinaceae rhodophyta based on galactan structures from the tetrasporophyte life stage
Carbohydrate Research, 2009Co-Authors: Ruth Falshaw, Richard H FurneauxAbstract:The identification of the polysaccharides from tetrasporophytic plants of nine endemic New Zealand species belonging to the Gigartinaceae, 'Gigartina' ancistroclada, 'G.' grandifida, Gigartina dilatata, G. divaricata, G. macrocarpa, G. marginifera, G. pachymenioides, G. sp. 'Lindauer 164' and Sarcothalia livida using infra-red spectroscopy in conjunction with constituent sugar and glycosyl linkage/substitution analysis is reported. All nine species contain galactans with structures consistent with lambda-type carrageenans. Differences in the structures of the galactans in these and a further six previously studied species indicate chemotaxonomically distinct groupings that correspond to Sarcothalia, 'Sarcothalia' and Gigartina genera plus some outliers. These distinct, chemotaxonomic groupings are aligned to those determined by rbcL sequence analysis reported in the literature.
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carrageenan from the tetrasporic stage of gigartina decipiens gigartinaceae rhodophyta
Carbohydrate Research, 1994Co-Authors: Ruth Falshaw, Richard H FurneauxAbstract:The structure of the polysaccharide isolated from tetrasporophytic plants of the New Zealand red alga Gigartina decipiens has been determined by chemical and spectroscopic techniques. It is a linear polymer composed primarily of alternating 3-linked beta-D-galactopyranosyl 2-sulphate and 4-linked alpha-D-galactopyranosyl 2,6-disulphate residues. About 15% of the 3-linked residues have an additional sulphate ester group at the 6-position. Aside from this small extra sulphate substitution, the structure is that of the idealised Lambda-Carrageenan. Good quality solution-state 13C NMR spectra were recorded and interpreted for this carrageenan and for the carrageenans produced from it by solvolytic desulphation and alkali modification.
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chemical methods for the analysis of sulphated galactans from red algae
Carbohydrate Research, 1991Co-Authors: Thomas T Stevenson, Richard H FurneauxAbstract:Methods are reported that facilitate the structural characterization of complex sulphated galactans of the red algae. Two procedures have been developed for the production of alditol acetates from carrageenans and agaroids. Both procedures generate 3,6-anhydrogalactitol acetate from the easily destroyed 3,6-anhydrogalactosyl residues in near quantitative yield. The "double hydrolysis-reduction" method involves preliminary hydrolysis under conditions sufficient to cleave all of the 3,6-anhydrogalactosidic bonds, but mild enough to avoid significant further degradation. The "reductive hydrolysis" method uses the acid-stable 4-methylmorpholine-borane to reduce the 3,6-anhydrogalactose end groups as they are released during acid hydrolysis. An alditol acetate sample can be prepared from a polysaccharide in a single tube, ready for g.l.c. analysis, in less than 2.5 h, i.e. more quickly than by any previous procedure. Problems associated with incomplete methylation of sulphated carrageenans and agaroids by the Hakomori procedure have been overcome by first converting the sulphated polysaccharide into its triethylammonium salt form. The reductive hydrolysis method is effective for the production of partially methylated alditol acetates from the methylated polysaccharides, enabling the rapid determination of the substitution pattern of these polysaccharides. These improved analytical methods have been applied successfully to kappa-, iota-, and Lambda-Carrageenans, as well as some agars.
José F. Mesquita - One of the best experts on this subject based on the ideXlab platform.
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Population studies and carrageenan properties of Chondracanthus teedei var. lusitanicus (Gigartinaceae, Rhodophyta)
Journal of Applied Phycology, 2004Co-Authors: Leonel Pereira, José F. MesquitaAbstract:Features of an intertidal population of Chondracanthus teedei var. lusitanicus , which occurs in sandy basins on rocky shores of part of the Portuguese coast (Buarcos, Figueira da Foz), were studied over one year. Biomass and plant size showed a small increase in early spring (April), a marked increase in early summer (June/July) and were at a minimum in late summer. There was generally more tetrasporophytes (4–32.5%) than female gametophytes (3–29%), which contrasts with other geographical regions where C. teedei populations have been studied, such as Brazil and France. However, non-fructified thalli predominated throughout the year. Phycocolloid extracts were compared for the various stages using spectroscopic methods (FTIR, FT-Raman, ^1H- and ^13C-NMR). These showed a hybrid carrageenan belonging to the lambda family in the tetrasporophyte and a hybrid kappa-iota-mu-nu carrageenan in the female gametophyte and non-fructified thalli. The average phycocolloid content was 34.9% dry weight, with a maximum of 43.6% in July. The combination of high available biomass and phycocolloid content makes this species a potentially important source of kappa/iota hybrid carrageenan in Portugal additional to the traditionally harvested carrageenophytes.
Leonel Pereira - One of the best experts on this subject based on the ideXlab platform.
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Research Article Population Studies and Carrageenan Properties in Eight Gigartinales (Rhodophyta) from Western Coast of Portugal
2016Co-Authors: Leonel PereiraAbstract:Copyright © 2013 Leonel Pereira.This is an open access article distributed under theCreative CommonsAttribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Eight carrageenophytes, representing seven genera and three families of Gigartinales (Florideophyceae), were studied for 15months. The reproductive status, dry weight, and carrageenan content have been followed by a monthly random sampling. The highest carrageenan yields were found in Chondracanthus acicularis (61.1%), Gigartina pistillata (59.7%), and Chondracanthus teedei var. lusitanicus (58.0%). Species of Cystocloniaceae family produces predominantly iota-carrageenans; Gigartinaceae family produces hybrid kappa-iota carrageenans (gametophytic plants) and lambda-family carrageenans (sporophytic plants); Phyllophoraceae family produces kappa-iota-hybrid carrageenans. Quadrate destructive sampling method was used to determine the biomass and line transect. Quadrate nondestructive sampling method, applied along a perpendicular transect to the shoreline, was used to calculate the carrageenophytes cover in two periods: autumn/winter and spring/summer. The highest cover and biomass were found in Chondrus crispus (3.75%–570 g/m2), Chondracanthus acicularis (3.45%–99 g/m2), Chondracanthus teedei var. lusitanicus (2.45%–207.5 g/m2), andMastocarpus stellatus (2.02%–520 g/m2). 1
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Population Studies and Carrageenan Properties in Eight Gigartinales (Rhodophyta) from Western Coast of Portugal
Hindawi Limited, 2013Co-Authors: Leonel PereiraAbstract:Eight carrageenophytes, representing seven genera and three families of Gigartinales (Florideophyceae), were studied for 15 months. The reproductive status, dry weight, and carrageenan content have been followed by a monthly random sampling. The highest carrageenan yields were found in Chondracanthus acicularis (61.1%), Gigartina pistillata (59.7%), and Chondracanthus teedei var. lusitanicus (58.0%). Species of Cystocloniaceae family produces predominantly iota-carrageenans; Gigartinaceae family produces hybrid kappa-iota carrageenans (gametophytic plants) and lambda-family carrageenans (sporophytic plants); Phyllophoraceae family produces kappa-iota-hybrid carrageenans. Quadrate destructive sampling method was used to determine the biomass and line transect. Quadrate nondestructive sampling method, applied along a perpendicular transect to the shoreline, was used to calculate the carrageenophytes cover in two periods: autumn/winter and spring/summer. The highest cover and biomass were found in Chondrus crispus (3.75%–570 g/m2), Chondracanthus acicularis (3.45%–99 g/m2), Chondracanthus teedei var. lusitanicus (2.45%–207.5 g/m2), and Mastocarpus stellatus (2.02%–520 g/m2)
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Population studies and carrageenan properties of Chondracanthus teedei var. lusitanicus (Gigartinaceae, Rhodophyta)
Journal of Applied Phycology, 2004Co-Authors: Leonel Pereira, José F. MesquitaAbstract:Features of an intertidal population of Chondracanthus teedei var. lusitanicus , which occurs in sandy basins on rocky shores of part of the Portuguese coast (Buarcos, Figueira da Foz), were studied over one year. Biomass and plant size showed a small increase in early spring (April), a marked increase in early summer (June/July) and were at a minimum in late summer. There was generally more tetrasporophytes (4–32.5%) than female gametophytes (3–29%), which contrasts with other geographical regions where C. teedei populations have been studied, such as Brazil and France. However, non-fructified thalli predominated throughout the year. Phycocolloid extracts were compared for the various stages using spectroscopic methods (FTIR, FT-Raman, ^1H- and ^13C-NMR). These showed a hybrid carrageenan belonging to the lambda family in the tetrasporophyte and a hybrid kappa-iota-mu-nu carrageenan in the female gametophyte and non-fructified thalli. The average phycocolloid content was 34.9% dry weight, with a maximum of 43.6% in July. The combination of high available biomass and phycocolloid content makes this species a potentially important source of kappa/iota hybrid carrageenan in Portugal additional to the traditionally harvested carrageenophytes.
