Rhodophyta

The influence of temperature, light, salinity and nutrient availability on the release of volatile halogenated hydrocarbons was investigated in the Antarctic red macroalgal species Gymnogongrus antarcticus Skottsberg. Compared to standard culture condition, an increase in the release rates of iodocompounds was generally found for the exposure of the alga to altered environmental conditions. Macroalgae exhibited higher release rates after adaptation for two months to the changed factors, than after short-term exposure. Monitoring the release rates during a 24 h incubation period (8.25 h light, 15.75 h darkness) showed that changes between light and dark periods had no influence on the release of volatile halocarbons. Compounds like bromoform and 1-iodobutane exhibited constant release rates during the 24 h period. The formation mechanisms and biological role of volatile organohalogens are discussed. Although marine macroalgae are not considered to be the major source of biogenically-...

Larvae of the Australian sea urchin Holopneustes purpurascens are induced to settle and metamorphose (termed settlement herein) by a water-soluble compound produced by the red alga Delisea pulchra, the main host plant of new recruits. The settlement cue for H. purpurascens had previously been identified as a floridoside-isethionic acid complex, and this paper presents new evidence correcting that finding. The actual settlement cue produced by D. pulchra was isolated from the polar extract by cationexchange chromatography and identified as histamine, using one-and two-dimensional nuclear magnetic resonance spectrometry. The chemical identity of the cue was confirmed by gas chromatography-mass spectrometry (GC-MS) and matrix-assisted laser desorption/ionization-timeof-flight mass spectrometry. Synthetic histamine and histamine at 4.5 M isolated from D. pulchra both induced rapid settlement in 80%-100% of the larvae of H. purpurascens. Lower concentrations of histamine (0.9 -2.3 M) induced larval settlement, but this response varied from 0%-90%. The histamine content of two host plants of H. purpurascens-D. pulchra and Ecklonia radiata-and of four other common species was quantified using GC-MS. D. pulchra had the highest histamine content, which is consistent with H. purpurascens recruiting to this species. Histamine was also detected in the seawater surrounding these host algae. This is the first time that a settlement cue has been quantified in the habitat of a marine organism.

Continuous metal ions biosorption from Pb/Cu and Pb/Cd solutions onto seaweed Gelidium sesquipedale and a composite material prepared from an industrial algal waste was performed in a packed bed column. A binary Langmuir equation describes well the equilibrium data and indicates a good adsorption capacity. In the sorption process, Cd and Cu break through the column faster than Pb due to its lower affinity for the biosorbent. An overshoot in the outlet Cd concentration was observed and explained by competitive adsorption between Pb and Cd, whereby the higher Pb affinity for the biosorbent displaces bound Cd ions. A small overshoot happens for Cu adsorption in the presence of Pb ions. Desorption using 0.1 M HNO 3 as eluant, was 100% effective. A mass transfer model for the adsorption and desorption processes, considering an external and intraparticle film resistance, adequately simulates the column performance. A binary Langmuir equation was used to describe equilibrium for the saturation process and a mass action law for the desorption process. Elution process is defined as an ion exchange mechanism, between protons and metal ions.

Macroalgae, in particular red and green species, are gaining interest as protein-rich foods for human consumption and sources of proteinaceous biofunctional peptide ingredients. During protein extraction the starting raw material, the cell disruption method utilized and the reagents employed have a major effect on the yield of protein recovered. A method is described herein for extraction and semi-purification of food-grade aqueous and alkaline soluble proteins from red and green macroalgae. Dried milled macroalgae are disrupted by osmotic shock with subsequent removal of aqueous soluble proteins by centrifugation. Alkaline soluble proteins are removed following consecutive treatment of the resultant pellet with an alkaline solution. Aqueous and alkaline soluble proteins are then enriched from the crude extracts by isoelectric precipitation.

Here we report the characterization of a new Gracilaria species from the Venice Lagoon , identified through molecular analyses, using the plastid large subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase (rbcL) and the intergenic Rubisco spacer (rbcL-rbcS), combined with morphological observations and pigment composition. This new entity, recorded in the artificial substrata of the Venice Gulf and never found in other localities of the Adriatic Sea, was not described by local or international literature up to now, and adds to the other 12 Gracilaria taxa recorded in the Mediterranean Sea. Thalli exhibit a green-yellowish pigmentation with pink shades and dense bushy and spiny branching in the distal portions. Tetrasporangial plants show abundant short spine-like uni-tribranched branchlets throughout the thallus. This species is an attached form growing on artificial rocky substrata of the low mid-littoral and upper sub-littoral zone in spring and early summer. Molecular analyses based on the plastidial rbcL gene showed a 99.68 % nucleotide identity with another Gracilaria sp. (named Gracilaria-LI02, GenBank AY651040) from southern Sicily reported by Gargiulo and collaborators in 2006 and not identifiable with any other species described for the Mediterranean Sea until now. Probably the recent finding of this new species is not due to an extra-Mediterranean introduction but is the consequence of its misidentification with other specimens whose morphologies are very similar: Gracilaria gracilis and Gracilaria conferta. Moreover the comparison of our rbcL-rbcS spacer sequences with those of these two cryptic species and the phylogenetic analyses confirmed that the Venice specimen is to consider a new distinct species.

The effects of five metals, copper (Cu), chromium (Cr), Zinc (Zn), cadmium (Cd) and lead (Pb), on photosynthetic activity, measured as pulse amplitude modulation (PAM) chlorophyll fluorescence yield, was monitored in seven species of green, red and brown macroalgae over a 14 d period. The 10 mmol l À1 of Cr and Zn reduced chlorophyll fluorescence of all species by day 4, and 10 mmol l À1 of Cu and Cd reduced the fluorescence of some species; however, fluorescence yields of all species were unaffected by 10 mmol l À1 of Pb. Metals were generally accumulated in the order of Cu4Pb4Zn4Cr4Cd. Ulva intestinalis accumulated the highest amounts of all metals, and Cladophora rupestris the lowest. A relationship between internal metal concentration and fluorescence was not always evident as in some cases fluorescence was reduced at low metal contents. In the case of Zn, fluorescence was lowest in plants which contained lowest concentrations after 14 d-exposure, possibly because plants had died and Zn leached out of the algal cells. The relationship between internal metal concentration and fluorescence was algal species and metal-specific.

Halymenia durvillei is a red seaweed with a great potential as sulphated galactan producer collected in the coastal waters of small island of Madagascar (Nosy-be in Indian Ocean). To elucidate the structure of its polysaccharide, NMR ( 1 H and 13 C), FTIR, HPAEC and different colorimetric methods were carried out. It has been shown that this polysaccharide, consisted mainly of galactose, was branched by xylose and galactose in minor amounts. Arabinose and fucose were also detected. This galactan was found highly sulphated (42%, w/w) and pyruvylated (1.8%, w/w). Analysis of glycosidic linkages by CPG-MS and 13 C NMR indicated that the polysaccharide has the defining linear backbone of alternating 3-␤-d-galactopyranosyl units and 4-linked ␣-l/d-galactopyranosyl residues. 3,6-Anhydrogalactose units have been also detected in minor quantity. This -carrageenan like polysaccharide has shown original sulphatation patterns with 2-O (26%) or 2/6-O (58%) sulphated 3-linked ␤-d-galactopyranosyl units and 6-O (19%) or 2/6-O (47%) 4-linked ␣-l/d-galactopyranosyl residues.

Diketopiperazines (DKPs), which are cyclic dipeptides, have been detected in a variety of natural resources. Recently, the interest in these compounds increased significantly because of their remarkable bioactivity. This review deals with the chemical structures, biosynthetic pathways, and biological activities of DKPs from marine microorganisms, sponges, sea stars, tunicates (ascidians), and red algae. The literature has been covered up to December 2008, and a total 124 DKPs from 104 publications have been discussed and reviewed. Some of these compounds have been found to possess various bioactivities including cytotoxicity, and antibacterial, antifungal, antifouling, plant-growth regulatory, and other activities.

Concentrations of Cu, Zn, Cd, Pb, Ni, Co, Fe, Mn, and Hg were measured successively in water, sediments, and six macroalgal species belonging to three algal classes during 3 years (2008-2010) from Abu Qir Bay, Alexandria, Egypt: Chlorophyceae (Enteromorpha compressa, Ulva fasciata), Phaeophyceae (Padina boryana), and Rhodophyceae (Jania rubens, Hypnea musciformis, Pterocladia capillacea). The study aimed to assess the bioaccumulation potential of the seaweeds, as well as to evaluate the extent of heavy metal contamination in the selected study site. Metals were analyzed using atomic absorption spectrophotometry coupled with MH-10 hydride system. The obtained data showed that the highest mean concentrations of Cu, Zn, Fe, and Mn were recorded in E. compressa; Cd, Ni, and Hg exhibited their highest mean concentrations in P. boryana, while Pb and Co were found in J. rubens. Abundance of the heavy metals in the algal species was as follow: Fe > Mn > Zn > Pb > Ni > Co >...

There has been significant recent interest in the commercial utilisation of algae based on their valuable chemical constituents many of which exhibit multiple bioactivities with applications in the food, cosmetic, agri-and horticultural sectors and in human health. Compounds of particular commercial interest include pigments, lipids and fatty acids, proteins, polysaccharides and phenolics which all display considerable diversity between and within taxa. The chemical composition of natural algal populations is further influenced by spatial and temporal changes in environmental parameters including light, temperature, nutrients and salinity, as well as biotic interactions. As reported bioactivities are closely linked to specific compounds it is important to understand, and be able to quantify, existing chemical diversity and variability. This review outlines the taxonomic, ecological and chemical diversity between, and within, different algal groups and the implications for commercial utilisation of algae from natural populations. The biochemical diversity and complexity of commercially important types of compounds and their environmental and developmental control are addressed. Such knowledge is likely to help achieve higher and more consistent levels of bioactivity in natural samples and may allow selective harvesting according to algal species and local environmental conditions for different groups of compounds.

Menurut beberapa refrensi, alga merah ( Rhodophyta ) adalah salah satu filum dari alga berdasarkan zat warna atau pigmentasinya dan organism yang berkloroplas yang dapat menghasilkan oksigen melalui proses fotosintesis. Dunia tumbuhan ganggang termasuk kedalam dunia thallophyta(tumbuhan talus) karena belum dapat dibedakann akar, batang dan daun secara jelas.
Menurut Philip Sze (1998), Ganggang bersifat autotrof (dapat menyusun makananya sendiri) dan hampir semua ganggang bersifat eukariot.kebanyakan ganggang adalah organisme akuatik yang tumbuh dengan baik ditempat gelap. Ganggang ini hidup dilaut bentuk tubuh seperti rumput sehingga di sebut rumput laut.tubuh bersel banyak dan berbentuk lembaran, talusnya mikroskopik dan multiselular serta berwarna merah karena mengandung fikoeritrin, tetapi alga merah juga memiliki pigmen lain yaitu fikobiliprotein. Walaupun sebagian besar ganggang merah hidup di laut namun banyak juga terdapat dilaut tropika. Ganggang merah yang sering ditemukan di air laut yakni Eucheuma  spinosum dapat ditemukan di laut dangkal.
Sebagai hasi asimilase terdapat sejenis karbohidrat yang disebut tepung floride, yang merupakan hasil polimerisasi glukosa berbentuk bulat tidak larut dalam air, seringkali berlapis-lapis, jika dibubuhi yodium berwarna kemerah-merahan. Tepung ini sifatnya lebih dekat pada glikogen, dan tidak terdapat dalam kromotofora, melainkan pada permukaannya. Selain terdapat florida terdapat juga floridosida (senyawa gliserin dan galoktosa) dan tetes minyak.

The anti-HMPV (human metapneumovirus) activity was determined for sulfated dl-hybrid galactans obtained from the red seaweed Cryptonemia seminervis and their depolymerized products obtained by reductive partial hydrolysis. Structural studies carried out in three homogeneous depolymerized fractions DS-1, DS-2e and DS-3 (Mw of 51.6-63.8 kDa) showed that these galactans present different chemical characteristics, as monosaccharide composition, content of sulfate groups (14.1-29.9%) and agaran:carrageenan molar ratio diads, 2.7:1 for DS-1 and DS-2e and 1:1 for DS-3. The sulfate groups are located principally on C-2 of ␤-d-galactopyranose and 4,6-O-(1 -carboxyethylidene)-␤d-galactopyranose residues and on C-6 of ␣-galactose residues. Sulfated dl-galactans and their depolymerized products exhibited antiviral activity at a very early stage of the viral infection cycle. All fractions, except DS-2e inhibited HMPV replication by binding to the viral particle. Besides depolymerized galactans DS-2e and DS-3 inhibited the recognition of cell receptor by HMPV and penetration to the host cell, respectively.

Carrageenophyte red seaweed from Oman, Hypnea bryoides, extracted using three different processes: an aqueous, a mild alkaline, and a more vigorous alkaline extraction was investigated. The resulting extract precipitated by alcohol was subject to chemical and rheological measurements. The total carbohydrate [ranged from 36.78 to 41.65 g/100 g], and ash [39.04 to 43.11 g/100 g] were the most abundant components in H. bryoides and contrary to the two, lipid content was found at a minimum [ranging from 2.95 to 3.38 g/100 g]. Alkali treatment with NaOH allowed complete conversion of kappa (κ) carrageenan form as detected by FTIR analysis. Total yield by alkali treatments gave higher yields (33%) compared with aqueous treatments (12%). However, subsequent aqueous treatment produced mixed carrageenan (μ and κ) with higher molecular weight compared with the alkali treatments which produced single carrageenan form (κ) with molecular weight of 4.1 × 10(5) Da. The effects of thermal history on gel-sol and sol-gel transition were investigated by differential scanning calorimeter (DSC) and rheology on a pure sample and 1.5% κ-carrageenan mixture added with 30 mM KCl. Transition temperatures from DSC and rheology showed comparable results and were in good agreement with those previously reported.

Analysis of nuclear small subunit ribosomal RNA gene (18S rDNA) sequence data from 123 samples of the red algal genus Bangia from mainland New Zealand has revealed diversity exceeding that reported for the genus from any other region in the world. Our study resolves two New Zealand Bangia taxa basal to the order Bangiales, and five clades of Bangia, four of which include New Zealand members. The basal taxa are separated from each other by 139 bp and differ from all other Bangia taxa in the New Zealand region by 103-163 bp over approximately 1750 bp 18S rDNA sequence data. Our results reveal a Bangia flora of previously unsuspected richness, and show that the simple morphology of these organisms obscures significant levels of genetic diversity. The presence of high diversity and retention of basal taxa in New Zealand Bangia raises the prospect that the southern hemisphere, and particularly eastern Gondwana, is not only a centre of diversity, but a centre of origin for the modern Bangiales.

Protein concentrate (PC) of Kappaphycus alvarezii (cultivated on the West coast of India), was extracted and its functional properties were evaluated. The K. alvarezii PC contained 62.3 ± 1.62% proteins. At pH 12, the nitrogen solubility of this PC was 58.72 ± 1.68% in the presence of 0.5 M NaCl. The emulsifying and foaming properties of this PC varied with time and pH. However, it formed remarkably stable emulsions with Jatropha oil after 720 min (i.e. E 720 = 53.67 ± 1.59). On the other hand, maximum foaming ability (53.33 ± 2.31%) of the PC was recorded at pH 4.0. This PC had high oil (1.29 ± 0.20 ml oil/g PC) and water absorption capacity (2.22 0.04 ml H 2 O/g PC). DSC analysis revealed thermal transitions at about 109.25°C at neutral pH. The results obtained in this investigation suggest the suitability of K. alvarezii PC as an inexpensive source of protein; thus this PC could be incorporated into several value-added food products.

Natural compounds offer interesting pharmacological perspectives for antiviral drug development with regard to broad-spectrum antiviral properties and novel modes of action. In this study, we have analyzed polysaccharide fractions isolated from Grateloupia indica. The crude water extract (GiWE) as well as one fraction (F3) obtained by anion exchange chromatography had potent anti-HSV activity. Their inhibitory concentration 50% (IC 50 ) values (0.12-1.06 lg/ml) were much lower than cytotoxic concentration 50% values (>850 lg/ml). These fractions, which were effective antiviral inhibitors if added only during the adsorption period, had very low anticoagulant activity. Furthermore, they had no direct inactivating effect on virions in a virucidal assay. Chemical, chromatographic and spectroscopic methods showed that the active polysaccharide, which has an apparent molecular mass of 60 kDa and negative specific rotation ½a 32 D À16°(c 0.2, H 2 O), contains a-(1 ! 4)-and a-(1 ! 3)-linked galactopyranose residues. Sulfate groups, if present, are located mostly at C-2/6 of (1 ! 4)-and C-4/6 of (1 ! 3)-linked galactopyranosyl units, and are essential for the anti herpetic activity of this polymer.

Production of seaweeds in Chile has fluctuated between 120,000 and 316,000 wet metric tons per year during the last ten years. The most important Phaeophyta are exploited for alginate production and as abalone feed. Among the Rhodophyta, Chilean production comes mainly from wild stocks, as at present cultivation on a commercial scale is restricted to Gracilaria. Large-scale production of this species has been the result of a sharp increase in the number of farms. During the last five years an important trend towards diversification of seaweed exploitation and cultivation has developed. The demand for brown algal materials for the alginate industry, abalone cultivation, seaweed flour production for human and animal feeding and the development of novel food products has encouraged the farming of Macrocystis pyrifera and of red edible seaweeds, such as Chondracanthus chamissoi and Callophyllis variegata, is also promoting the development of cultivation activities.

In this study, we screened eight terpenes isolated from the organic extract of Sphaerococcus coronopifolius for their antifouling activity in order to find possible new sources of non-toxic or less toxic bioactive antifoulants. The anti-settlement activity (EC 50 ) and the degree of toxicity (LC 50 ) of S. coronopifolius metabolites was evaluated using larvae of the cirriped crustacean Amphibalanus (Balanus) amphitrite (cyprids and nauplii) as model organism. For five of eight tested metabolites EC 50 was lower than 5 mg/L. The most promising results were observed for bromosphaerol (3), which expressed an EC 50 value of 0.23 mg/L, in combination with low toxicity levels (LC 50 >100 mg/L). The therapeutic ratio-an index used to estimate whether settlement inhibition is due to toxicity or other mechanismsis also calculated and discussed.

Background: An interaction between lectins from marine algae and PLA 2 from rattlesnake was suggested some years ago. We, herein, studied the effects elicited by a small isolectin (BTL-2), isolated from Bryothamnion triquetrum, on the pharmacological and biological activities of a PLA 2 isolated from rattlesnake venom (Crotalus durissus cascavella), to better understand the enzymatic and pharmacological mechanisms of the PLA 2 and its complex.

Two new polyoxygenated steroids, namely, penicisteroids A and B (1 and 2), were obtained from the culture extract of Penicillium chrysogenum QEN-24S, an endophytic fungus isolated from an unidentified marine red algal species of the genus Laurencia. In addition, seven known steroids (3-9) were also isolated and identified. The structures of these compounds were established on the basis of extensive spectroscopic analysis. The absolute configuration for compound 1 was determined by application of the modified Mosher's method. Penicisteroid A (1), which is a structurally unique steroid having tetrahydroxy and C-16-acetoxy groups, displayed potent antifungal and cytotoxic activity in the preliminary bioassays. Preliminary structure-activity relationships are discussed.

Este estudio es el primer registro para Colombia del género Hildenbrandia, representando el primer hallazgo de Rhodophyta dulceacuícola. Se incluye la descripción detallada de los caracteres morfométricos, así como la distribución ambiental de las poblaciones recolectadas en tres localidades del departamento de Santander. Se concluye que la especie corresponde a la circunscripción de Hildenbrandia angolensis; caracterizada por su diámetro celular pequeño (= 4.8 μm) y de distribución tropical a subtropical. Se documentaron propágulos vegetativos en una sola población. H. angolensis se presentó en ríos cercanos a zonas de cascada, con temperatura de 16-18 ºC, pH de neutral a ligeramente alcalino (6.9-7.6), alto contenido de iones (272-1174 μS cm -1 ), velocidad de corriente muy alta (140 cm s -1 ) y sitios sombreados con poca profundidad (< 60 cm); cobertura algal de esta especie sobre la roca entre 3.2-4.1 m 2 . H. angolensis se registra en la cuenca alta del río de Oro y río Frío, en bosque seco a muy húmedo montano bajo, municipios de Piedecuesta y Floridablanca (Santander, Colombia).

Systematics of the red algal order Corallinales has a long and convoluted history. In the present study, molecular approaches were used to assess the phylogenetic relationships based on the analyses of two datasets: a large dataset of SSU sequences including mainly sequences from GenBank; and a combined dataset including four molecular markers (two nuclear: SSU, LSU; one plastidial: psbA; and one mitochondrial: COI). Phylogenetic analyses of both datasets re-affirmed the monophyly of the Corallinales as well as the two families (Corallinaceae and Hapalidiaceae) currently recognized within the order. Three of the four subfamilies of the Corallinaceae (Corallinoideae, Lithophylloideae, Metagoniolithoideae) were also resolved as a monophyletic lineage whereas members of the Mastophoroideae were resolved as four distinct lineages. We therefore propose to restrict the Mastophoroideae to the genera Mastophora, Metamastophora, and possibly Lithoporella in the aim of rendering this subfamily monophyletic. In addition, our phylogenies resolved the genus Hydrolithon in two unrelated lineages, one containing the generitype Hydrolithon reinboldii and the second containing Hydrolithon onkodes, which used to be the generitype of the now defunct genus Porolithon. We therefore propose to resurrect the genus Porolithon for the second lineage encompassing those species with primarily monomerous thalli, and trichocyte arrangements in large pustulate horizontal rows. Moreover, our phylogenetic analyses revealed the presence of cryptic diversity in several taxa, shedding light on the need for further studies to better circumscribe species frontiers within the diverse order Corallinales, especially in the genera Mesophyllum and Neogoniolithon.

Membrane transporters (MTs) facilitate the movement of molecules between cellular compartments. The evolutionary history of these key components of eukaryote genomes remains unclear. Many photosynthetic microbial eukaryotes (e.g., diatoms, haptophytes, and dinoflagellates) appear to have undergone serial endosymbiosis and thereby recruited foreign genes through endosymbiotic/horizontal gene transfer (E/HGT). Here we used the diatoms Thalassiosira pseudonana and Phaeodactylum tricornutum as models to examine the evolutionary origin of MTs in this important group of marine primary producers. Using phylogenomics, we used 1,014 diatom MTs as query against a broadly sampled protein sequence database that includes novel genome data from the mesophilic red algae Porphyridium cruentum and Calliarthron tuberculosum, and the stramenopile Ectocarpus siliculosus. Our conservative approach resulted in 879 maximum likelihood trees of which 399 genes show a non-lineal history between diatoms and other eukaryotes and prokaryotes (at the bootstrap value $70%). Of the eukaryote-derived MTs, 172 (ca. 25% of 697 examined phylogenies) have members of both red/green algae as sister groups, with 103 putatively arising from green algae, 19 from red algae, and 50 have an unresolved affiliation to red and/or green algae. We used topology tests to analyze the most convincing cases of non-lineal gene history in which red and/or green algae were nested within stramenopiles. This analysis showed that ca. 6% of all trees (our most conservative estimate) support an algal origin of MTs in stramenopiles with the majority derived from green algae. Our findings demonstrate the complex evolutionary history of photosynthetic eukaryotes and indicate a reticulate origin of MT genes in diatoms. We postulate that the algal-derived MTs acquired via E/HGT provided diatoms and other related microbial eukaryotes the ability to persist under conditions of fluctuating ocean chemistry, likely contributing to their great success in marine environments.

In recent years, much attention has been focused on polysaccharides isolated from natural sources. The aim of this study was to investigate the in vitro and in vivo antitumor properties of a sulfated polysaccharide isolated from the seaweed C. feldmannii (Cf-PLS). Hematological, biochemical and histopathological analyses were performed in order to evaluate the toxicological aspects related to Cf-PLS treatment. Its effects on the immunological system were also investigated. The Cf-PLS did not show any significant in vitro cytotoxicity at the experimental exposure levels that were used, but showed in vivo antitumor effect. The inhibition rates of sarcoma 180 tumor development were 48.62 and 48.16% at the doses of 10 and 25 mg kg −1 , respectively. In addition, Cf-PLS was also able to increase the response elicited by 5-fluorouracil (5-FU) from 48.66 to 68.32%. The histopathological analysis of liver and kidney showed that both organs were moderately affected by Cf-PLS-treatment. Neither enzymatic activity of alanine aminotransferase nor urea or creatinine levels were significantly altered. In hematological analysis, leucopeny was observed after 5-FU treatment, but this effect was prevented when the treatment was associated with the Cf-PLS. It was also demonstrated that Cf-PLS acts as an immunomodulatory agent, raising the production of specific antibodies, and increasing the production of OVA-specific antibodies. It also induced a discreet hyperplasia of lymphoid folicules of the white pulp in the spleen of treated mice. In conclusion, Cf-PLS has some interesting anticancer activity that could be associated with its immunostimulating properties.

Nuclear genome sequencing from extremophilic eukaryotes has revealed clues about the mechanisms of adaptation to extreme environments, but the functional consequences of extremophily on organellar genomes are unknown. To address this issue, we assembled the mitochondrial and plastid genomes from a polyextremophilic red alga, Galdieria sulphuraria strain 074 W, and performed a comparative genomic analysis with other red algae and more broadly across eukaryotes. The mitogenome is highly reduced in size and genetic content and exhibits the highest guanine-cytosine skew of any known genome and the fastest substitution rate among all red algae. The plastid genome contains a large number of intergenic stem-loop structures but is otherwise rather typical in size, structure, and content in comparison with other red algae. We suggest that these unique genomic modifications result not only from the harsh conditions in which Galdieria lives but also from its unusual capability to grow heterotr...

First-generation Sanger DNA sequencing revolutionized science over the past three decades and the current next-generation sequencing (NGS) technology has opened the doors to the next phase in the sequencing revolution. Using NGS, scientists are able to sequence entire genomes and to generate extensive transcriptome data from diverse photosynthetic eukaryotes in a timely and cost-effective manner. Genome data in particular shed light on the complicated evolutionary history of algae that form the basis of the food chain in many environments. In the Eukaryotic Tree of Life, the fact that photosynthetic lineages are positioned in four supergroups has important evolutionary consequences. We now know that the story of eukaryotic photosynthesis unfolds with a primary endosymbiosis between an ancestral heterotrophic protist and a captured cyanobacterium that gave rise to the glaucophytes, red algae and Viridiplantae (green algae and land plants). These primary plastids were then transferred to other eukaryotic groups through secondary endosymbiosis. A red alga was captured by the ancestor(s) of the stramenopiles, alveolates (dinoflagellates, apicomplexa, chromeridae), cryptophytes and haptophytes, whereas green algae were captured independently by the common ancestors of the euglenophytes and chlorarachniophytes. A separate case of primary endosymbiosis is found in the filose amoeba Paulinella chromatophora, which has at least nine heterotrophic sister species. Paulinella genome data provide detailed insights into the early stages of plastid establishment. Therefore, genome data produced by NGS have provided many novel insights into the taxonomy, phylogeny and evolutionary history of photosynthetic eukaryotes.

Page 1. 432 Int. J. Environment and Pollution, Vol. 33, No. 4, 2008 Copyright © 2008 Inderscience Enterprises Ltd. Seaweed future cultivation in Chile: perspectives and challenges Alejandro H. Buschmann*, María del Carmen Hernández-González and Daniel Varela ...

closely linked to the overgrowth of seagrass by filamentous algal epiphytes when high light and CO 2 were combined. Importantly, all seagrass plants maintained positive leaf growth throughout the experiment, indicating that growth was inhibited by some experimental conditions but not arrested entirely. Therefore, while greater light or elevated CO 2 provided direct physiological benefits for seagrasses, such benefits were likely negated by overgrowth of epiphytic algae when greater light and CO 2 were combined. This result demonstrates how indirect ecological effects from epiphytes can modify independent physiological predictions for seagrass associated with global change.

a b s t r a c t R-Phycoerythrin (R-PE) is one of the three phycobiliproteins which are extensively used as fluorescent probes, and it is prepared from red macro-algae. This macromolecular protein has gained importance in many biotechnological applications in food science, immunodiagnostic, therapy, cosmetics, protein and cell labeling, and analytical processes. In the present investigation, R-PE was isolated and purified from a red alga Portieria hornemannii. R-PE extracted and purified through ammonium sulfate precipitation (55%) followed by Q-Sepharose column chromatography had yielded a maximum purity of 5.2%. R-PE exhibited a typical "three-peak" with absorption maxima at 499, 545 and 565 nm. CD spectrum of R-PE yielded the following secondary structure data: alpha helix (14.30%), beta helix (28.10%), turn helix (19.20%) and random coil helix (38.40%). The molecular mass of R-PE was 240 kDa under Native-PAGE. Three different subunits such as ␣, ␤ and ␥ of 16 kDa, 21 kDa and 39 kDa were segregated under SDS-PAGE. On two dimensional gel electrophoresis, one basic and four acidic subunits were detected. Five different tryptic peptides were assigned under MALDI-TOF. The sequences of N-terminus of R-PE of 10 different amino acids are Met Lys Gln Met Trp Asp Arg Met Val Val. The preparative procedures of the R-PE extraction and purification established based on the experiments exhibit advantages and can offer a reference for R-PE preparation from other marine red macro-alga P. hornemannii.