Chondracanthus Acicularis Research Articles

Quantitative Screening of Phytochemicals of five Red Seaweeds from the Northern Kerala Coast, India

The Quantitative analysis of 5 phytochemical parameters: Tannins, Flavonoids, Phenols, Steroids, and Terpenoids has been done for 5 Red seaweeds belonging to the family –Rhodophyceae i.e. Gracilaria corticata, Grateloupia lithophila, Gelidium micropterum, Chondracanthus acicularis, and Centroceras clavulatum, from the Northern Kerala coast: Thikkodi, Elathur, Kappad and Beypore, located in the Kozhikode district. Methanolic extracts of the seaweeds were used for the Phytochemical component screening. The study found that Flavonoid content was the lowest among other parameters ranging from 2.61±0.04 mg QE/g dw to 5.57±0.23 QE/g dw. The steroid was found to be higher in the case of C. acicularis (61.32±0.04 mg BSE/g dw) and C. clavulatum (65.80±0.02 mg BSE/g dw). Followed by it was Tannin which was highest in G. micropterum (49.20±0.56 mg CE/g dw) and C. acicularis (32.01±0.24 mg CE/g dw), whereas G. lithophila showed consistently lower concentrations in Phenols (0.19±0.01 mg GAE/g dw), Tannins (9.43±1.59 mg CE/g dw), and Steroids (3.69±0.01 mg BSE/g dw). To the best of our Knowing the current Quantitative analysis of phytochemicals in Red seaweeds is the pioneering work done in the following study areas: Kappad, Elathur, and Beypore. This phytochemical screening with reference to past studies on the same domain confirms that a lot of work needs to be done yet.

Temporal and spatial variation of seaweed biomass and assemblages in Northwest Portugal

Seaweed are ecologically important organisms playing a central structural and functional role in coastal ecosystems (providing habitat, mating and nursery grounds, food and refuge for several marine organisms). Additionally, their commercial potential has been rising since seaweed are directly or indirectly used by humans in many countries. This work aimed to evaluate the temporal and spatial variation of target species biomass and the composition of seaweed assemblages at an exposed rocky shore, in Northern Portugal. The targeted species were: Codium spp., Chondrus crispus, Mastocarpus stellatus, Osmundea pinnatifida and Chondracanthus acicularis. Two sampling sites were defined and in each one 18 haphazard placed quadrats (50 × 50 cm) were sampled: 9 in the low-shore and 9 in the mid-shore. Sampling was conducted periodically from April 2017 to January 2018, in six sampling occasions. Significant temporal variation was detected in the mean biomass values of Codium spp. and O. pinnatifida, at low-shore, where high abundance of these species in typically cold months could be related to the atypical warmer year 2017 in Portugal. C. acicularis revealed a significant spatial variation at both shore levels, which could be explained by different water channels orientations at the two sampling sites. The multivariate analysis showed that the effect of sampling occasion on the seaweed assemblage structure depended on site and revealed that some species, such as Ulva spp., apparently play an important role in seaweed assemblages of Belinho-Mar intertidal and highlights its ecological importance for these community. This study provides a baseline data for future work in similar areas, allowed the development of effective management plans as basis for seaweed exploitation guidelines.

Biostimulants Derived from Moroccan Seaweeds: Seed Germination Metabolomics and Growth Promotion of Tomato Plant

Polysaccharides extracted from seaweeds can function as plant biostimulants. The aim of this study was to assess the effects of Polysaccharide Enriched Extracts (PEEs) obtained from 17 Moroccan seaweeds, on tomato seed germination and plant growth. Three concentrations (0.02, 0.05 and 0.1 mg mL−1) of PEEs were applied to tomato seeds to evaluate their effect on 3 germination parameters: germination percentage (GP), germination speed (GS) and mean germination time (MGT). Metabolomic analysis by GC–MS was subsequently performed on seedlings. In the second experiment, four PEEs concentrations (0.02, 0.05, 0.1 and 0.2 mg mL−1) were used as foliar spray or as soil application to tomato plants. Their growth parameters (number of leaves, shoot length, fresh and dry weight of stem and roots) and biochemical parameters (chlorophyll a and b) were measured. Results indicated a significant increase of GP and GS associated with a significant reduction of MGT of tomato seeds treated with 0.02 mg mL−1 of PEEs obtained from Gigartina sp., Gigartina pistillata, Chondracanthus acicularis, Gelidium crinale, Schizymenia dubyi, Cystoseira. foeniculacea and Fucus spiralis. Similar results were also obtained by application of higher PEEs concentration (0.1 mg mL−1) extracted from Ulva rigida, Codium tomentosum, Codium decorticatum and Bifurcaria bifurcata. Metabolomic analysis on seedlings detected the presence of some metabolites which could possibly be involved in seed germination enhancement or inhibition. The results of the second experiment showed that the same PEEs cited above at the same concentrations enhanced plant dry weight and chlorophyll a content except Gigartina sp., C. foeniculacea and C. decorticatum. Furthermore, soil application of PEEs was more effective in improving plant growth parameters than foliar application. The study shows the potential of PEEs from Moroccan seaweed to be used as biostimulants for a sustainable agriculture.

Macroalgal responses to coastal urbanization: relative abundance of indicator species

This study aimed to evaluate and compare the intertidal macroalgae community from reef structures subject to different urbanization degrees. Samplings were made in 11 beaches from the Pernambuco coast, northeastern Brazil. The sites were classified according to the level of urbanization into three classes of increasing urbanization pressure: non urbanized (NU), in urbanization process (UP), and consolidated urbanization (UC). Macroalgae were identified in situ non-destructively. A total of 53 taxa were identified, 41 of these were macroalgae. Significant differences were observed in the composition of macroalgae according to the urbanization levels, with Palisada perforata, Gelidiella acerosa, and Caulerpa spp. dominating NU and UP sites, whereas Chondracanthus acicularis, Bryopsis sp., and Ulva spp. dominated UC sites. This work shows that urbanization can have a strong effect on the structure of rocky intertidal macroalgal assemblages and highlights some macroalgae species that can be used as bioindicators for assessing the impact of urbanization on coastal shores.

Polysaccharides extracted from Moroccan seaweed: a promising source of tomato plant growth promoters

The present study investigates the use of seaweed polysaccharides as biostimulants of seed germination and plant growth. Seventeen species of Moroccan seaweeds were collected and screened for their crude polysaccharide content which ranged from 0.3 to 34% (dry weight basis). Chemical analyses of the obtained polysaccharide-enriched extracts (PEEs) were performed. Two bioassays were carried out to study seed germination and growth-promoting activity of PEEs. In the first experiment, the effect of PEEs on tomato seed germination was carried out under in vitro conditions. Half-strength Murashige-Skoog medium was supplemented with different PEEs at the concentration of 0.2 mg mL−1 (w/v). The germination percentage was recorded daily over 4 days. In a second experiment, tomato plants were grown in greenhouse conditions and watered with aqueous solution of seaweed PEEs (0.1 mg mL−1). After 30 days, the evaluated plant growth parameters were plant length, fresh and dry weight of plants shoots and roots, as well as chlorophyll content. Results showed that six seaweed species were a promising source of PEEs with beneficial effect on germination, plant biomass, and chlorophyll content. Two green seaweeds: Ulva rigida and Codium decorticatum, two red seaweeds: Gigartina sp. and Chondracanthus acicularis, and two brown seaweeds: Fucus spiralis and Bifurcaria bifurcata enhanced seed germination and plant growth. Nevertheless, the PEEs obtained from the red seaweed Gigartina pistillata inhibited seed germination. Principal component analysis of the results showed positive correlation between the sulfate content of PEEs and shoot dry weight as well as chlorophyll content.

Contribution to the biochemical (macronutritional and pigmentary) study of the red alga Chondracanthus acicularis at the sites of El Jadida and Sidi Rahal

Event Abstract Back to Event Contribution to the biochemical (macronutritional and pigmentary) study of the red alga Chondracanthus acicularis at the sites of El Jadida and Sidi Rahal Sara EL MOUTTAQUI1, 2*, Nor Eddine REZZOUM2, Yasmine BAHY1, Fouzia HMIMID1, Hakima ZIDANE2 and Mohammed BEKKALI1 1 University of Hassan II Casablanca, Biology, Morocco 2 Institut National de Recherche Halieutique (INRH), Morocco Algae are a very important renewable resource in marine ecosystems. They play a key role in mitigating the adverse effects of climate change through the photosynthesis process. In Morocco, algal biodiversity is very rich. However, few species are exploited on an industrial scale like the agarophytes Gelidium and Gracilaria. Other algae belonging to the genus Gigartina are exported in their raw state. To ensure the sustainability of these renewable resources, management plans are required; Hence the bio-ecology study of Chondracanthus acicularis was conducted in three sites on the Moroccan Atlantic coast (Sidi Rahal, El Jadida and Souiria Lkdima). These sites were chosen according to the exploitation level. Results of this study will be used to implement rational management. In a second part, a biochemical study was done to evaluate proteins, carbohydrates and total lipids concentrations at the two sites (Sidi Rahal and El Jadida) for the four seasons of the year 2017. The biochemical results showed concentration variations in the two sites and even through the four seasons, this is speculated to be related to environmental parameters. Keywords: Chondracanthus acicularis, biochemical analysis, El jadida, Sidi Rahal, macronutrients Conference: IMMR'18 | International Meeting on Marine Research 2018, Peniche, Portugal, 5 Jul - 6 Jul, 2018. Presentation Type: Poster Presentation Topic: Seafood Technology Citation: EL MOUTTAQUI S, REZZOUM N, BAHY Y, HMIMID F, ZIDANE H and BEKKALI M (2019). Contribution to the biochemical (macronutritional and pigmentary) study of the red alga Chondracanthus acicularis at the sites of El Jadida and Sidi Rahal. Front. Mar. Sci. Conference Abstract: IMMR'18 | International Meeting on Marine Research 2018. doi: 10.3389/conf.FMARS.2018.06.00140 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 27 Apr 2018; Published Online: 07 Jan 2019. * Correspondence: PhD. Sara EL MOUTTAQUI, University of Hassan II Casablanca, Biology, Casablanca, Morocco, sara.elmouttaqui@gmail.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Sara EL MOUTTAQUI Nor Eddine REZZOUM Yasmine BAHY Fouzia HMIMID Hakima ZIDANE Mohammed BEKKALI Google Sara EL MOUTTAQUI Nor Eddine REZZOUM Yasmine BAHY Fouzia HMIMID Hakima ZIDANE Mohammed BEKKALI Google Scholar Sara EL MOUTTAQUI Nor Eddine REZZOUM Yasmine BAHY Fouzia HMIMID Hakima ZIDANE Mohammed BEKKALI PubMed Sara EL MOUTTAQUI Nor Eddine REZZOUM Yasmine BAHY Fouzia HMIMID Hakima ZIDANE Mohammed BEKKALI Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Typification of algae described by Simón de Rojas Clemente y Rubio deposited at the Herbarium of the University of Granada (Spain)

A typification is presented for two names of algae described by Clemente. The types of Fucus digitatus var. pellucidus Clemente ex Colmeiro (1867: 213) and Fucus tomentosus var. fastigiatus Clemente ex Bellón (1942: 11) were designated by Cremades (1990) after the review conducted on the algal herbarium of Simón de Rojas Clemente y Rubio (1777–1827). Although both names remained unpublished, they now are preserved in the collection of nomenclatural types at the Herbarium of the University of Granada (GDA), Spain. In addition, the discovery of other old material supports the proposal of Cremades (1993) on applying the name Fucus confervoides var. macrocarpus Clemente (1807: 314) to the species now known as Chondracanthus acicularis (Roth 1806: 114) Fredericq in Hommersand et al. (1993: 117).

Characterization of glycosyl inositol phosphoryl ceramides from plants and fungi by mass spectrometry

Although glycosyl inositol phosphoryl ceramides (GIPCs) represent the most abundant class of sphingolipids in plants, they still remain poorly characterized in terms of structure and biodiversity. More than 50years after their discovery, little is known about their subcellular distribution and their exact roles in membrane structure and biological functions. This review is focused on extraction and characterization methods of GIPCs occurring in plants and fungi. Global methods for characterizing ceramide moieties of GIPCs revealed the structures of long-chain bases (LCBs) and fatty acids (FAs): LCBs are dominated by tri-hydroxylated molecules such as monounsaturated and saturated phytosphingosine (t18:1 and t18:0, respectively) in plants and mainly phytosphingosine (t18:0 and t20:0) in fungi; FA are generally 14-26 carbon atoms long in plants and 16-26 carbon atoms long in fungi, these chains being often hydroxylated in position 2. Mass spectrometry plays a pivotal role in the assessment of GIPC diversity and the characterization of their structures. Indeed, it allowed to determine that the core structure of GIPC polar heads in plants is Hex(R1)-HexA-IPC, with R1 being a hydroxyl, an amine, or a N-acetylamine group, whereas the core structure in fungi is Man-IPC. Notably, information gained from tandem mass spectrometry spectra was most useful to describe the huge variety of structures encountered in plants and fungi and reveal GIPCs with yet uncharacterized polar head structures, such as hexose-inositol phosphoceramide in Chondracanthus acicularis and (hexuronic acid)4-inositol phosphoceramide and hexose-(hexuronic acid)3-inositol phosphoceramide in Ulva lactuca.

Evaluation of the in vitro methods for micropropagation of Chondracanthus acicularis (Roth) Fredericq (Gigartinales, Rhodophyta): tissue culture and production of protoplasts

Tissue was cultured and protoplasts isolated from the carrageenophyte Chondracanthus acicularis with the aim of developing micropropagation as an alternative to harvesting raw material from natural beds. Both adventitious shoots and filamentous calluses were induced by tissue culture on medium solidified with 0.4–1 % (w/v) agar. Adventitious shoots were mainly produced from discoid bases while filamentous calluses were mainly induced from basal zones and sub-apical explants. A gradient of the regeneration ability was observed from the top to the bottom of the thallus. The discoid base was the most reactive explant and produced the highest number of adventitious shoots compared to basal zones and sub-apical explants, irrespective of the concentration of agar. Protoplasts were isolated enzymatically from the whole thallus using a combination of cellulase R-10 Onozuka, macerozyme R-10, and crude extract of the gland gut of algivorous molluscs. The highest mean yield of protoplasts (1.2 × 106 protoplasts g−1 fresh weight) was obtained after 16 h of digestion with an enzyme mixture containing 2 % (w/v) cellulase R-10, 1 % (w/v) macerozyme R-10 Onozuka, 4 % (v/v) crude extract of gut gland of Haliotis, 0.8 M mannitol, 50 mM sodium citrate, 0.3 % (w/v) bovine serum albumin. Depending on the conditions, mean protoplast yields ranged from 3.14 × 105 to 1.2 × 106 protoplasts g−1 fresh weight. Different factors (storage duration, mannitol, sodium citrate, crude extract of the gland gut of algivorous molluscs) were tested to improve the yield of protoplasts but none has a significantly effect.

Population Studies and Carrageenan Properties in Eight Gigartinales (Rhodophyta) from Western Coast of Portugal

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).

Benthic assemblages of rock pools in northern Portugal: seasonal and between-pool variability

We investigated the seasonal (winter vs summer and within season) and spatial (between-pool) variability of benthic assemblages of rock pools at mid-intertidal level along the shore of Viana do Castelo (North Portugal). Physical traits of rock pools, including size, depth and position along the shore, were also compared between pools. While pools did not differ for any of the examined physical traits, results indicated a clear seasonal difference in the structure of assemblages, including a total of 49 macroalgal and 13 animal taxa. This finding was driven by six taxa that are more abundant in winter (the reef-forming polychaete Sabellaria alveolata , the articulated coralline algae Corallina spp., the brown alga Bifurcaria bifurcata , the encrusting coralline alga Lithophyllum incrustans , the red alga Chondracanthus acicularis and the grazing snails Gibbula spp.) and four algal taxa that are more abundant in summer (the invasive brown Sargassum muticum , the green Ulva spp., the kelp Laminaria ochroleuca and the filamentous red Ceramium spp.). These data provide a new contribution to the knowledge of rock pool systems and have potential implications for monitoring programmes aimed at assessing ecological modifications related to natural and anthropogenic disturbances and for identifying processes responsible for the variability of rock pool assemblages.

FTIR-ATR spectroscopy as a tool for polysaccharide identification in edible brown and red seaweeds

Phycocolloids present in three brown ( Himanthalia elongata, Bifurcaria bifurcata, Saccharina latissima) and five red edible seaweeds ( Mastocarpus stellatus, Gigartina pistillata, Chondracanthus acicularis, Nemalion helminthoides and Dumontia contorta) were studied by FTIR-ATR spectroscopy. Infrared spectra of polysaccharide standards (alginate, agar, iota-, kappa- and lambda-carrageenan) were obtained for comparison. The main polysaccharide found in brown seaweeds was alginate, a linear copolymer of mannuronic (M) and guluronic acid (G). Alginate M/G ratio was tentatively estimated from specific absorption bands (808/787 cm −1 and 1030/1080 cm −1) in infrared spectra, suggesting higher values of mannuronic than guluronic acid blocks (M/G > 1) for brown seaweeds. According to their infrared spectra, all the red seaweeds studied were mainly carrageenan producers. Thus, M. stellatus showed absorption bands at 929.0, 844.7 and 803.2 cm −1 of a typical hybrid kappa/iota/mu/nu-carrageenan, meanwhile G. pistillata and C. acicularis, showed the characteristic broad band (830–820 cm −1) of lambda-type carrageenan. Moreover, when the second-derivative was obtained to improve resolution of overlapped bands in the original FTIR spectra, this band was divided into several sharper signals, indicating the presence of lambda-/theta-/xi-carrageenans. Accordingly with their FTIR spectra, N. helminthoides contained sulphated polysaccharides, such as carrageenan or mannans, while D. contorta produced lambda- with lesser amounts of kappa-carrageenan. Therefore, FTIR-ATR spectroscopy is proposed as a useful tool for the food, pharmaceutical and cosmetics industry to check the phycocolloid quality of a raw seaweed material by a quick and non-destructive method.

Portuguese carrageenophytes: Carrageenan composition and geographic distribution of eight species (Gigartinales, Rhodophyta)

Eight carrageenophytes from the Centre and North coast of Portugal, representing seven genera and three families of Gigartinales, were studied in 15 different coastal stations in a geographic study, from Baleal (Peniche), in the central zone, to Moledo, in the northern zone.In order to characterize the different carrageenan types, 1H NMR spectroscopy was used to identify and quantify the different carrageenan fractions in the extracted phycocolloids (both water and alkali extractions). Thereby, detailed information concerning the properties and structure of these polysaccharides at molecular level was revealed.Based on the results of the analysis of the carrageenan types, the following conclusions were made: female gametophytes and non-fertile thalli of Chondrus crispus, Mastocarpus stellatus, Chondracanthus teedei var. lusitanicus, Gigartina pistillata, Chondracanthus acicularis and Gymnogongrus crenulatus, presented a varying degrees of kappa–iota hybrid carrageenan (co-polymers of kappa–iota carrageenan). The kappa/iota ratio ranged from 0 to 2.2. The carrageenans extracted from Ahnfeltiopsis devoniensis were mainly iota-carrageenan, but some geographic variations in the composition of carrageenans were found. Calliblepharis jubata contained carrageenans of iota-type in all reproductive stages. Lambda-family carrageenans were found in tetrasporophytes of C. cripus (lambda), M. stellatus (lambda), C. teedei var. lusitanicus (hybrid xi–theta), C. acicularis (hybrid xi–theta) and G. pistillata (hybrid xi–lambda).

A comparative analysis of phycocolloids produced by underutilized versus industrially utilized carrageenophytes (Gigartinales, Rhodophyta)

Carrageenan (E-407) and semi-refined carrageenan (E-407a) are some of the main additives used by the food industry for their gelling, emulsifying, thickening, and stabilizing properties. These are natural ingredients, which have been used for decades in food applications and are generally regarded as safe. Internationally, sub-tropical carrageenophytes (e.g., Kappaphycus alvarezii) are cultivated extensively as a source of raw materials for industrial extraction, and their use as potential candidates in integrated multitrophic aquaculture is tentative. We analyzed carrageenan yield (as a percentage of dry weight) and chemical composition (by Fourier transform infrared attenuated total reflection and Fourier transform-Raman) of extracts produced by several carrageenophytes (Gigartinales, Rhodophyta), from different origins, e.g., K. alvarezii (Tanzania, Indonesia, the Philippines, Panama, and Mexico), Kappaphycus striatum (Madagascar), Eucheuma denticulatum (Tanzania, the Philippines, and Madagascar), Betaphycus gelatinum (the Philippines), Chondracanthus chamissoi, and Sarcothalia crispata (Chile). For comparison, some underutilized carrageenophytes were also analyzed, e.g., Chondrus crispus, Mastocarpus stellatus, Gigartina pistillata, Chondracanthus teedei var. lusitanicus, Chondracanthus acicularis, Calliblepharis jubata, Gymnogongrus crenulatus, and Ahnfeltiopsis devoniensis (Portuguese carrageenophytes). The main findings were that the highest carrageenan yield was obtained from K. striatum (Madagascar) with 75.6 (percent dry weight (% DW)); B. gelatinum and K. alvarezii (both from the Philippines) had yields of 71.0% and 68.0% (% DW), respectively; and G. pistillata (Portugal) 65.4% (% DW). Spectroscopic analysis of the phycocolloids allowed determination of a wide range of carrageenan types, e.g., pure iota carrageenan, several kappa–iota hybrid carrageenans with different iota/kappa ratios, and kappa–beta, xi–theta, and xi–lambda hybrid carrageenans.

Use of FTIR, FT-Raman and 13C-NMR spectroscopy for identification of some seaweed phycocolloids

Many seaweeds produce phycocolloids, stored in the cell wall. Members of the Rhodophyceae produce polysaccharides the main components of which are galactose (galactans)—agar and carrageenan. In addition, alginic acid is extracted from members of the Phaeophyceae. This is a binary polyuronide made up of mannuronic acid and guluronic acid. The wide uses of these phycocolloids are based on their gelling, viscosifying and emulsifying properties, which generate an increasing commercial and scientific interest. In this work, the FTIR and FT-RAMAN spectra of carrageenan and agar, obtained by alkaline extraction from different seaweeds (e.g. Mastocarpus stellatus, Chondrus crispus, Calliblepharis jubata, Chondracanthus acicularis, Chondracanthus teedei and Gracilaria gracilis), were recorded in order to identify the type of phycocolloid produced. The spectra of commercial carrageenan, alginic acid and agar samples (SIGMA and TAAB laboratories) were used as references. Special emphasis was given to the 500–1500 cm −1 region, which presents several vibrational modes, sensitive to the type of polysaccharide and to the type of glycosidic linkage. The FT-Raman spectra present a higher resolution than FTIR spectra, this allowing the identification of a larger number of characteristic bands. In some cases, phycocolloids can be identified by FT-Raman spectroscopy alone.

Carrageenophytes of occidental Portuguese coast: 1-spectroscopic analysis in eight carrageenophytes from Buarcos bay

Infrared and Raman spectroscopic analysis of the carrageenan (alkaline extraction) in eight species (representing seven genera and four families) of Gigartinales, in different reproductive phases from Buarcos bay (Figueira da Foz, Portugal), were studied. Female gametophytes and non-fertile thalli samples of Chondrus crispus, Mastocarpus stellatus, Chondracanthus teedei var. lusitanicus, Gigartina pistillata and Chondracanthus acicularis present a κ-carrageenan profile or varying degrees of a κ–ι hybrid. The presence of κ–ι hybrid carrageenan in C. teedei var. lusitanicus was confirmed by 13C NMR . The carrageenans extracted from Gymnogongrus crenulatus and Ahnfeltiopsis devoniensis are constituted mainly by ι-carrageenan but seasonal variations in the nature of carrageenans are present. λ-Family carrageenans were found in tetrasporophytes of C. crispus, M. stellatus, C. teedei var. lusitanicus, C. acicularis and G. pistillata. Calliblepharis jubata presents carrageenans of ι-type in all reproductive stages.

The introduced alga Undaria pinnatifida (Laminariales, Alariaceae) in the lagoon of Venice

Since its appearance in 1992 in the lagoon of Venice, the brown algae Undaria pinnatifida (kelp) has gradually expanded along the banks of canals both at Chioggia and Venice, becoming the dominant species in the local algal community chiefly from February to July. In Chioggia Island, where another brown seaweed (Sargassum muticum) is present since 1992, the spreading of Undaria reaches a plateau. In Venice Island, instead, the colonisation process is still in progress. During 1999, the kelp has colonised the main canals (e.g. The Grand Canal) and, subsequently, the small inner ones. In order to evaluate the dynamics of substrate re-colonisation by Undaria, two mechanical eradications were carried out during (March) and after the fertile period (July) of the algae. Such experimental manipulations provided evidence of the fast re-colonisation potential of the algae mainly attributable to its efficient reproductive system. Eradication made during the fertile period, in fact, permitted the kelp development during the following year, while re-colonisation has started 2 years later where eradication was performed after the reproductive period. A significant decrease in the surface covered by other species has been observed both in shallow (Ulva rigida, Enteromorpha spp., Antithamnion pectinatum, Chondracanthus acicularis) and deeper areas (Rhodymenia ardissonei) during the period of maximum development of U. pinnatifida. On the basis of the results of this study, the following conclusions can be drawn: (1) the alga U. pinnatifida is continuously expanding in lagoon environments of Venice; (2) in order to limit its spreading, mechanical eradications would be done on a large spatial scale and before the zoospores release; (3) there is suggestive evidence of competition between Undaria and the remaining indigenous algae.