ABSTRACT
Gracilariales is a clade of florideophycean red macroalgae known for being the main source of agar. We present a de novo genome assembly and annotation of Gracilaria domingensis, an agarophyte alga with flattened thallus widely distributed along Central and South American Atlantic intertidal zones. In addition to structural analysis, an organizational comparison was done with other Rhodophyta genomes. The nuclear genome has 78 Mbp, with 11,437 predicted coding genes, 4,075 of which did not have hits in sequence databases. We also predicted 1,567 noncoding RNAs, distributed in 14 classes. The plastid and mitochondrion genome structures were also obtained. Genes related to agar synthesis were identified. Genes for type II galactose sulfurylases could not be found. Genes related to ascorbate synthesis were found. These results suggest an intricate connection of cell wall polysaccharide synthesis and the redox systems through the use of L-galactose in Rhodophyta. The genome of G. domingensis should be valuable to phycological and aquacultural research, as it is the first tropical and Western Atlantic red macroalgal genome to be sequenced.
Subject(s)
Genome, Mitochondrial , Gracilaria , Rhodophyta , Agar/metabolism , Galactose/metabolism , Gracilaria/genetics , Rhodophyta/genetics , Rhodophyta/metabolismABSTRACT
BACKGROUND: Banana and papaya are among the most important crops in the tropics, with a value amounting to millions of dollars per year. However, these fruits suffer significant losses due to anthracnose, a fungal disease. It is well known that certain seaweed extracts possess antifungal activity, but no published data appear to exist on the practical application of this property. In the present study, five organic Brazilian seaweed extracts were screened for their activity against banana and papaya anthracnose fungi. Furthermore, cytotoxic and mutagenic effects of the extracts were evaluated by the brine shrimp lethality assay and the Allium cepa root-tip mutagenicity test respectively, while their major components were identified by gas chromatography/mass spectrometry. RESULTS: Strong fungus-inhibitory effects of Ochtodes secundiramea and Laurencia dendroidea extracts were observed on both papaya (100 and 98% respectively) and banana (89 and 78% respectively). This impressive activity could be associated with halogenated terpenes, the major components of both extracts. Only Hypnea musciformis extract showed cytotoxic and mutagenic effects. CONCLUSION: The results of this study suggest the potential use of seaweed extracts as a source of antifungal agents with low toxicity to control anthracnose in papaya and banana during storage.
Subject(s)
Antifungal Agents/pharmacology , Colletotrichum/drug effects , Fruit/microbiology , Plant Diseases/microbiology , Rhodophyta/chemistry , Seaweed/chemistry , Terpenes/pharmacology , Animals , Antifungal Agents/adverse effects , Antifungal Agents/analysis , Artemia/drug effects , Carica/microbiology , Diet , Food Microbiology , Humans , Musa/microbiology , Mutagens , Plant Diseases/prevention & control , Plant Extracts/adverse effects , Plant Extracts/chemistry , Plant Extracts/pharmacology , Rhodophyta/adverse effects , Terpenes/adverse effects , Terpenes/analysis , Tropical ClimateABSTRACT
Ocean acidification has increased due to the enhanced solubility of CO2 in seawater. Mangrove macroalgae in tropical and subtropical coastal regions can benefit from the higher availability of CO2 for photosynthesis and primary production. However, they can be negatively affected by the simultaneously occurring warming and increased salinity in estuaries. Thus, we analyzed the isolated effects of ocean acidification and the interactive effects of increased temperature and salinity on the low molecular weight carbohydrate (LMWC) contents of the mangrove red macroalgae Bostrychia montagnei and Bostrychia calliptera from Brazilian tropical and subtropical populations. Specimens from both climatic niches were tolerant to pH decreased by CO2 enrichment and enhanced their LMWC contents under increased availability of CO2. Specimens from both climatic niches also accumulated their dulcitol and sorbitol contents to cope with warming and salt stress. Nevertheless, temperature of 34 °C was lethal for tropical macroalgae, while 29 °C and 31 °C were lethal for subtropical B. calliptera under salinity of 35. Tropical and subtropical B. montagnei synthesized dulcitol (5-110 mmol kg-1 dry weight) and sorbitol (5-100 mmol kg-1 dry weight) as osmoregulatory, energy and thermal protection compounds, whereas tropical and subtropical B. calliptera synthesized mainly dulcitol (10-210 mmol kg-1 dry weight). Although digeneaside has an energy function in Bostrychia spp., it is not an osmolyte or thermal protection compound. Our data demonstrated that both tropical and subtropical Bostrychia spp. benefit from ocean acidification by CO2 enrichment, increasing their LMWC contents. However, warming and increased salinity in estuaries will be detrimental to them, even they producing protective metabolites. Multifactorial approaches are recommended to investigate whether negative effects of increased temperature and salinity nullify positive effects of ocean acidification on these Bostrychia species/populations.
Subject(s)
Seawater , Seaweed , Seawater/chemistry , Salinity , Hydrogen-Ion Concentration , Carbon Dioxide/analysis , Ocean Acidification , Molecular Weight , Temperature , Carbohydrates , Sorbitol , Galactitol , Oceans and Seas , Global WarmingABSTRACT
Marine heatwaves (MHWs) frequency and intensity are increasing around the globe, affecting marine ecosystems' structure and functioning. Understanding how key marine species respond to these short-term extreme events is urgent for predicting damage to coastal ecosystems. Hypnea pseudomusciformis presents distribution in different floristic provinces on the Brazilian coast: tropical, transition and warm-temperate. Here, we evaluate the effects of simulated heatwaves on H. pseudomusciformis populations by measuring the changes in algal growth, pigment content, and photosynthesis. Based on data for the last four decades, we characterized the MHW patterns for each of the three collection sites. Perturbation levels were identified as average intensity heatwave (Δ +2 °C), maximum intensity heatwave (Δ +4 °C) and extreme intensity heatwave (Δ +6 °C), with an average duration of seven days. Based on growth rate data, corroborated with measurements of photosynthesis fluorescence and pigment contents. H. pseudomusciformis populations exhibit distinct tolerance and physiological responses to MHWs. The tropical and transition specimens were affected by Δ + 4 °C and Δ + 6 °C MHW scenarios, while the warm-temperate specimens was the only one to recover in all the MHW scenarios tested. These data are worrisome under a global warming scenario and an increase in MHWs, indicating that tropical and transition specimens of H. pseudomusciformis may be at risk of local extinction. This knowledge will be fundamental in driving any future management intervention or policy change for the conservation of marine ecosystems.
Subject(s)
Seaweed , Adaptation, Psychological , Ecosystem , Global Warming , Heat-Shock ResponseABSTRACT
Increased greenhouse gas concentrations in the Earth's atmosphere have resulted in global change, such as ocean warming and sea level rise. Increased salinity in estuaries is expected as a result of sea level rise and warming. Thus, we analysed the interactive effects of increased temperature and salinity on multiple physiological responses of Bostrychia montagnei and B. calliptera from two biogeographic provinces, Tropical Southwestern Atlantic (TSA) and Warm Temperate Southwestern Atlantic (WTSA). Macroalgae were cultured under three salinities (15, 25 and 35 PSU) and three temperatures: mean sea surface temperature (SST: 27 °C for TSA and 24 °C for WTSA), an RCP8.5 ocean warming scenario (SST + 5 °C), and a maximum temperature to test the algal upper thermal tolerance limits (RCP8.5 + 2 °C). Macroalgae from both localities decreased their growth under increased temperature and salinity. RCP8.5 + 2 °C was lethal for both macroalgae from TSA. RCP8.5 and RCP8.5 + 2 °C at 35 PSU were lethal for B. calliptera from WTSA, due to the interactive effects between increased temperature and salinity. Overall, increased salinity decreased the effective quantum yield and relative electron transport rate in algal photosynthesis. Our results demonstrated that the macroalgae synthesized proteins, carbohydrates (polysaccharides and low molecular weight carbohydrates), and antioxidants to tolerate detrimental temperatures and salinities. Our results also demonstrated that the macroalgae adjusted their pigment contents (phycobiliproteins, total carotenoids, and chlorophyll a) for efficient light-harvesting under thermal and saline stress. Our findings suggest that ocean warming and increased salinity in estuaries will be detrimental to B. montagnei and B. calliptera populations from both biogeographic provinces, especially to those from TSA that already live closer to their upper thermal tolerance limits.
Subject(s)
Rhodophyta , Seaweed , Animals , Birds , Carbohydrates , Chlorophyll A , Global Warming , Oceans and Seas , Salinity , TemperatureABSTRACT
The present study reports the Gas Chromatography-Mass Spectrometry (GC-MS) evaluation of the hexanes and dichloromethane fractions from extracts of the red alga Centroceras clavulatum (C. Agardh) Montagne. Twenty three compounds were identified, totaling ca. 42% of both fractions (0.18 g mass extract). The main constituents of the fractions were hexadecanoic acid (17.6%) and pentadecanoic acid (15.9%). Several secondary metabolites with interesting biological activity, such as (-)-loliolide, neophytadiene, phytol were identified. In addition, several classes of secondary metabolites, including phenolic compounds (e.g., phenylacetic acid), terpene derivatives, fatty acids, halogenated compound (e.g., 2-chlorocyclohexenol), lignoids, steroids, esters, amides (e.g., hexadecanamide), ketones, carboxylic acids, aldehydes and alcohols were observed. The occurrence of several of these structural classes is described for the first time in this species. The same fractions analyzed by GC-MS, and a separate set of polar fractions, were evaluated against two life cycle stages (epimastigote and trypomastigote forms) of the protozoan Trypanosoma cruzi and against phytopatogenic fungi Cladosporium cladosporiodes and C. sphaerospermum. The dichloromethane fraction was active against both T. cruzi forms (epimastigote IC(50) = 19.1 µg.mL-1 and trypomastigote IC(50) = 76.2 µg.mL-1). The hexanes and ethyl acetate fractions also displayed activity against both fungi species (200 µg) by TLC-bioautography.
Subject(s)
Chemistry, Pharmaceutical/methods , Cladosporium/drug effects , Fatty Acids/pharmacology , Palmitic Acid/pharmacology , Plant Extracts , Rhodophyta/chemistry , Trypanosoma cruzi/drug effects , Chagas Disease/drug therapy , Chagas Disease/parasitology , Cladosporium/growth & development , Fatty Acids/chemistry , Gas Chromatography-Mass Spectrometry , Hexanes/chemistry , Humans , Hydrophobic and Hydrophilic Interactions , Methylene Chloride/chemistry , Mycoses/drug therapy , Mycoses/microbiology , Palmitic Acid/chemistry , Plant Extracts/analysis , Plant Extracts/chemistry , Plant Extracts/pharmacology , Solvents/chemistry , Species Specificity , Trypanosoma cruzi/growth & developmentABSTRACT
Dictyota menstrualis (Hoyt) Schnetter, Hörning & Weber-Peukert (Dictyotales, Phaeophyceae) was studied for the production of oil-based bioproducts and co-products. Experiments were performed to evaluate the effect of carbon dioxide (CO2) concentration, under nitrogen (NO3 (-)) limiting and saturation conditions, on growth rate (GR), photosynthesis, as well as nitrate reductase (NR), carbonic anhydrase (CA), and Rubisco activities. In addition, the biochemical composition of D. menstrualis under these conditions was estimated. GR, protein content, and N content in D. menstrualis were higher in treatments containing NO3 (-), irrespective of CO2 addition. However, when CO2 was added to medium saturated with NO3 (-), values of maximum photosynthesis, Rubisco, and NR activity, as well as total soluble carbohydrates and lipids, were increased. CA activity did not vary under the different treatments. The fatty acid profile of D. menstrualis was characterized by a high content of polyunsaturated fatty acids, especially the omega-3 fatty acids, making it a possible candidate for nutraceutical use. In addition, this species presented high GR, photosynthetic rate, and fatty acid content, highlighting its economic importance and the possibility of different biotechnological applications.
Subject(s)
Carbon Dioxide/pharmacology , Fatty Acids, Omega-3/biosynthesis , Nitrates/pharmacology , Phaeophyceae/metabolism , Photosynthesis/drug effects , Algal Proteins/genetics , Algal Proteins/metabolism , Bioreactors , Carbon/metabolism , Carbon Dioxide/metabolism , Carbonic Anhydrases/genetics , Carbonic Anhydrases/metabolism , Dietary Supplements/analysis , Gene Expression , Nitrates/metabolism , Nitrogen/metabolism , Phaeophyceae/genetics , Photoperiod , Photosynthesis/genetics , Ribulose-Bisphosphate Carboxylase/genetics , Ribulose-Bisphosphate Carboxylase/metabolismABSTRACT
A screening was performed using nine marine-derived fungi as biocatalysts and the natural products (-)-ambrox® (1), (-)-sclareol (2), and (+)-sclareolide (3) in order to select the microorganisms able to catalyze the biooxidation of these compounds. It was observed that only the Aspergillus sydowii CBMAI 934, Botryosphaeria sp., Eutypella sp., and Xylaria sp. presented active oxidoreductases and catalyzed the regioselective hydroxylation in the natural products. The hydroxylated metabolites obtained were 1ß-hydroxy-ambrox (1a) (14%, A. sydowii CBMAI 934); 3ß-hydroxy-ambrox (1b) (17%, Botryosphaeria sp.; 11%, Eutypella sp.); 3ß-hydroxy-sclareol (2a) (31%, Xylaria sp.; 69%, Botryosphaeria sp.; 55%, Eutypella sp.); 18-hydroxy-sclareol (2b) (10%, Xylaria sp.); and 3ß-hydroxy-sclareolide (3a) (34%, Botryosphaeria sp.; 7%, Eutypella sp.). This is the first report of biohydroxylation of (-)-ambrox® (1), (-)-sclareol (2), and (+)-sclareolide (3) by whole mycelia of marine-derived fungi.
Subject(s)
Aspergillus/metabolism , Biological Products/metabolism , Diterpenes/metabolism , Furans/metabolism , Naphthalenes/metabolism , Penicillium/metabolism , Porifera/microbiology , Animals , Atlantic Ocean , Biotransformation , Brazil , Catalysis , Diterpenes/chemistry , Furans/chemistry , Hydroxylation , Molecular Structure , Naphthalenes/chemistry , Oxidation-ReductionABSTRACT
The macroalga Gracilaria domingensis is an important resource for the food, pharmaceutical, cosmetic, and biotechnology industries. G. domingensis is at a part of the food web foundation, providing nutrients and microelements to upper levels. As seaweed storage metals in the vacuoles, they are considered the main vectors to magnify these toxic elements. This work describes the evaluation of the toxicity of binary mixtures of available metal cations based on the growth rates of G. domingensis over a 48-h exposure. The interactive effects of each binary mixture were determined using a toxic unit (TU) concept that was the sum of the relative contribution of each toxicant and calculated using the ratio between the toxicant concentration and its endpoint. Mixtures of Cd(II)/Cu(II) and Zn(II)/Ca(II) demonstrated to be additive; Cu(II)/Zn(II), Cu(II)/Mg(II), Cu(II)/Ca(II), Zn(II)/Mg(II), and Ca(II)/Mg(II) mixtures were synergistic, and all interactions studied with Cd(II) were antagonistic. Hypotheses that explain the toxicity of binary mixtures at the molecular level are also suggested. These results represent the first effort to characterize the combined effect of available metal cations, based on the TU concept on seaweed in a total controlled medium. The results presented here are invaluable to the understanding of seaweed metal cation toxicity in the marine environment, the mechanism of toxicity action and how the tolerance of the organism.
Subject(s)
Gracilaria/drug effects , Metals, Heavy/toxicity , Models, Biological , Seaweed/drug effects , Cations/toxicity , Gracilaria/growth & development , Inhibitory Concentration 50 , Seaweed/growth & development , Toxicity TestsABSTRACT
The present study reports a 48-h aquatic metal-toxicity assay based on daily growth rates of the red seaweed Gracilaria domingensis (Gracilariales, Rhodophyta) in synthetic seawater. The median inhibitory concentration (IC50) for each metal cation was experimentally determined, and the ratios of free ions (aqueous complex) were calculated by software minimization of the total equilibrium activity (MINTEQA2) to determine the free median inhibitory concentration (IC50F). A model for predicting the toxicity of 14 metal cations was developed using the generic function approximation algorithm (GFA) with log IC50F values as the dependent variables and the following properties as independent variables: ionic radius (r), atomic number (AN), electronegativity (Xm ), covalent index (Xm (2) r), first hydrolysis constant (|log KOH |), softness index (σp ), ion charge (Z), ionization potential (ΔIP), electrochemical potential (ΔEo ), atomic number divided by ionization potential (AN/ΔIP), and the cation polarizing power for Z(2) /r and Z/AR. The 3-term independent variables were predicted as the best-fit model (log IC50F: -23.64 + 5.59 Z/AR + 0.99 |log KOH | + 37.05 σp ; adjusted r(2) : 0.88; predicted r(2) : 0.68; Friedman lack-of-fit score: 1.6). This mathematical expression can be used to predict metal-biomolecule interactions, as well as the toxicity of mono-, bi-, and trivalent metal cations, which have not been experimentally tested in seaweed to date. Quantitative ion-character relationships allowed the authors to infer that the mechanism of toxicity might involve an interaction between metals and functional groups of biological species containing sulfur or oxygen.
Subject(s)
Gracilaria/drug effects , Metals/toxicity , Seaweed/drug effects , Water Pollutants, Chemical/toxicity , Cations , Models, Biological , Seawater , ThermodynamicsABSTRACT
We surveyed the distribution and diversity of fungi associated with eight macroalgae from Antarctica and their capability to produce bioactive compounds. The collections yielded 148 fungal isolates, which were identified using molecular methods as belonging to 21 genera and 50 taxa. The most frequent taxa were Geomyces species (sp.), Penicillium sp. and Metschnikowia australis. Seven fungal isolates associated with the endemic Antarctic macroalgae Monostroma hariotii (Chlorophyte) displayed high internal transcribed spacer sequences similarities with the psychrophilic pathogenic fungus Geomyces destructans. Thirty-three fungal singletons (66%) were identified, representing rare components of the fungal communities. The fungal communities displayed high diversity, richness and dominance indices; however, rarefaction curves indicated that not all of the fungal diversity present was recovered. Penicillium sp. UFMGCB 6034 and Penicillium sp. UFMGCB 6120, recovered from the endemic species Palmaria decipiens (Rhodophyte) and M. hariotii, respectively, yielded extracts with high and selective antifungal and/or trypanocidal activities, in which a preliminary spectral analysis using proton nuclear magnetic resonance spectroscopy indicated the presence of highly functionalised aromatic compounds. These results suggest that the endemic and cold-adapted macroalgae of Antarctica shelter a rich, diversity and complex fungal communities consisting of a few dominant indigenous or mesophilic cold-adapted species, and a large number of rare and/or endemic taxa, which may provide an interesting model of algal-fungal interactions under extreme conditions as well as a potential source of bioactive compounds.
Subject(s)
Fungi/physiology , Seaweed/microbiology , Antarctic Regions , Antifungal Agents/pharmacology , Bacteria/drug effects , DNA, Ribosomal Spacer/genetics , Fungi/chemistry , Fungi/classification , Fungi/genetics , Fungi/isolation & purification , Microbial Sensitivity Tests , Seawater/chemistry , Seawater/microbiology , Trypanocidal Agents/pharmacology , Trypanosoma cruzi/drug effects , Tubulin/geneticsABSTRACT
Xylans from five seaweeds belonging to the order Nemaliales (Galaxaura marginata, Galaxaura obtusata, Tricleocarpacylindrica, Tricleocarpa fragilis, and Scinaia halliae) and one of the order Palmariales (Palmaria palmata) collected on the Brazilian coasts were extracted with hot water and purified from acid xylomannans and/or xylogalactans through Cetavlon precipitation of the acid polysaccharides. The ß-D-(1â4), ß-D-(1â3) 'mixed linkage' structures were determined using methylation analysis and 1D and 2D NMR spectroscopy. The presence of large sequences of ß-(1â4)-linked units suggests transient aggregates of ribbon- or helical-ordered structures that would explain the low optical rotations.
Subject(s)
Rhodophyta/chemistry , Xylans/chemistry , Carbohydrate Conformation , Magnetic Resonance Spectroscopy , Methylation , Optical Phenomena , Stereoisomerism , Xylans/isolation & purificationABSTRACT
The culture and physiology of red macroalgae calluses are well documented. To date, however, no report has either performed a cytochemical analysis or characterized the ultrastructural organization of calluses at different stages of development and under the effect of plant growth regulators. Therefore, to undertake such analyses, this work studied the red seaweed Gracilariopsis tenuifrons (Bird et Oliveira) Fredericq et Hommersand. Morphology studies suggested three types of calluses: a) terminal callus having an irregular amorphous shape and filamentous projections originating from the cortical region of the thallus; b) apical callus growing on apical branches and having an elongated semispherical shape; and c) intercalary callus developing along the intermediary region of the thallus and having the appearance of small declivities with irregular edges. The abundance of intercalary calluses over terminal and apical calluses is most likely a result of a major cortical surface that would support the cellular growth required to generate calluses. Callus development was initially observed as a matrix of cellular disorganization with filamentous projections; then, the cellular mass seemed to become more compact with spherical uncolored aspect. The presence of starch grains in the inner part of the explant could be explained by absorption from the culture medium and by proper biosynthesis during callus development. Cell wall reaction to staining suggested cellulose and agar composition with acidic polysaccharides. Results suggest that none of the three morphological types of calluses showed any significant differences on the basis of either cytochemistry or ultrastructural organization.
Subject(s)
Seaweed/cytology , Seaweed/ultrastructure , Histocytochemistry , MicroscopyABSTRACT
Specimens of the red alga Bostrychia tenella J. Agardh (Rhodomelaceae, Ceramiales) were collected from the São Paulo coast and submitted to room temperature solvent extraction. The resulting extract was fractionated by partitioning with organic solvent. The n-hexane (BT-H) and dichloromethane (BT-D) fractions showed antiprotozoal potential in biological tests with Trypanosoma cruzi and Leishmania amazonensis and presented high activity in an antifungal assay with the phytopathogenic fungi Cladosporium cladosporioides and Cladosporium sphaerospermum. Chromatography methods were used to generate subfractions from BT-H (H01 to H11) and from BT-D (D01 to D19). The subfractions were analyzed by gas chromatography-mass spectrometry (GC/MS), and the substances were identified by retention index (Kovats) and by comparison to databases of commercial mass spectra. The volatile compounds found in marine algae were identified as fatty acids, low molecular mass hydrocarbons, esters and steroids; some of these have been previously described in the literature based on other biological activities. Moreover, uncommon substances, such as neophytadiene were also identified. In a trypanocidal assay, fractions BT-H and BT-D showed IC(50) values of 16.8 and 19.1 microg/mL, respectively, and were more active than the gentian violet standard (31 microg/mL); subfractions H02, H03, D01 and D02 were active against L. amasonensis, exhibiting IC(50) values of 1.5, 2.7, 4.4, and 4.3 microg/mL, respectively (standard amphotericin B: IC(50)=13 microg/mL). All fractions showed antifungal potential. This work reports the biological activity and identification of compounds by GC/MS for the marine red alga B. tenella for the first time.
Subject(s)
Antifungal Agents/pharmacology , Leishmania/drug effects , Plant Extracts/pharmacology , Rhodophyta/chemistry , Trypanocidal Agents/pharmacology , Animals , Antifungal Agents/isolation & purification , Gas Chromatography-Mass Spectrometry , Plant Extracts/isolation & purification , Trypanocidal Agents/isolation & purificationABSTRACT
Abstract Alzheimer's disease affects nearly 36.5 million people worldwide, and acetylcholinesterase inhibition is currently considered the main therapeutic strategy against it. Seaweed biodiversity in Brazil represents one of the most important sources of biologically active compounds for applications in phytotherapy. Accordingly, this study aimed to carry out a quantitative and qualitative assessment of Hypnea musciformis (Wulfen) J.V. Lamouroux, Ochtodes secundiramea (Montagne) M.A. Howe, and Pterocladiella capillacea (S.G. Gmelin) Santelices & Hommersand (Rhodophyta) in order to determine the AChE effects from their extracts. As a matter of fact, the O. secundiramea extract showed 48% acetylcholinesterase inhibition at 400 μg/ml. The chemical composition of the bioactive fraction was determined by gas chromatography–mass spectrometry (GC–MS); this fraction is solely composed of halogenated monoterpenes, therefore allowing assignment of acetylcholinesterase inhibition activity to them.
ABSTRACT
Abstract Marine environment is one of the most important sources regarding natural products research. Besides, marine microorganisms have been denominated as a talented natural source for discovery of new leads. Although the association of macroalgae and fungi has been described regarding ecological issues, there is a lack of studies about marine seaweed endophytic fungi. In this context, the goal of this study was to evaluate cytotoxic, antifungal and antibacterial activities of endophytic fungi isolated from the Brazilian marine seaweed Bostrychia tenella (J.V. Lamouroux) J. Agardh (Ceramiales, Rhodophyta). Forty-five endophytic microorganism strains were isolated from B. tenella. Crude extracts and organic fractions of ten selected strains were obtained after growth in rice medium. Samples were evaluated for cytotoxicity, antifungal and antibacterial assays. Penicillium strains showed positive results in a diversity of assays, and other five strains were active in at least one test. In addition, cytochalasin D was isolated from Xylaria sp. This alga is composed of a microbiological potential, since its endophytic strains exhibited remarkable biological properties. Moreover, cytochalasin D isolation has confirmed chemical potential of marine endophytic strains. This is the first study in which cultured fungi isolates from the Brazilian macroalga B. tenella were evaluated concerning biological properties. Results corroborated that this species could be a pharmaceutical source from marine environment. Furthermore, Acremonium implicatum is being firstly described as marine endophyte and Xylaria sp., Trichoderma atroviride and Nigrospora oryzae as marine seaweed endophytes. Thus, this work reports the first study relating detailed isolation, cultivation and biological evaluation (cytotoxic, antifungal and antibacterial) of endophytes Penicillium decaturense and P. waksmanii from the Brazilian marine red alga B. tenella. We are also reporting the isolation of cytochalasin D, a known antitumor and antibiotic compound, from Xylaria sp. strain. Despite widespread prevalence in terrestrial and marine habitats, this present work describes the first occurrence of cytochalasin D as a metabolite from marine seaweed endophyte.
ABSTRACT
This study describes the diversity of benthic marine algae from insular areas of the southern Brazilian coast. Algal samples were collected between 2006 and 2010 during the winter and the summer seasons at three sites in the coastal waters of Paraná, Brazil: Ilha do Mel, Currais Archipelago and Ilha do Farol. The samples were collected along parallel transects on the coast. In this survey, Paraná marine phycoflora comprised 139 taxa (90 Rhodophyta, 27 Chlorophyta and 22 Phaeophyceae). Fifty-two species represent new records for the state, and 14 taxa are present at all sampling sites and in both seasons. Higher diversities of rhodophytes and chlorophytes were observed at Ilha do Mel, while phaeophytes were more diverse at Currais Archipelago. Lower algal diversity was observed at Ilha do Farol, a sampling station which is near an urban area. Ceramiaceae, Rhodomelaceae and Corallinaceae were dominant among Rhodophyta, Cladophoraceae and Ulvaceae among Chlorophyta, and Dictyotaceae and Sargassaceae among Phaeophyceae. Seasonal and spatial differences in species composition could be explained by the availability of consolidated substrate, water transparency and proximity to an urban area. Seaweed biodiversity from the Paraná coast also presents low species richness compared to other Brazilian states as a result of the shorter coastline, lower availability of rocky shores, and the location between estuarine systems (Paranaguá and Guaratuba Bays). These bays input a large amount of continental water, resulting in decreased salinity, high concentrations of suspended particulate matter and low transparency in the water column. Knowledge of seaweed diversity is essential for conservation studies. In addition, environmental monitoring programs undertaken during medium- to long-term seasonal changes could be improved to reflect changes detected through new records, the introduction of alien species in the area of interest, or even dominance of opportunistic species over other taxa. Therefore, a database able to support the monitoring of biodiversity is a fundamental step in detecting environmental impacts that could change seaweed biogeography, mainly in urbanized and harbor areas.
O presente estudo descreve a diversidade de algas marinhas bentônicas em áreas insulares da costa do Paraná, sul do Brasil. As amostras de algas foram coletadas entre 2006 e 2010 durante o inverno e o verão, em três locais: Ilha do Mel, Arquipélago de Currais e Ilha do Farol. A amostragem foi realizada ao longo de transectos paralelos à linha de costa e, na Ilha dos Currais, em diferentes profundidades. A ficoflora marinha paranaense é composta por 139 táxons (90 Rhodophyta, 27 Chlorophyta e 22 Phaeophyceae). Cinquenta e duas espécies são novas citações para o Estado do Paraná, e 14 táxons foram registrados em todos os locais estudados durante o verão e o inverno. Diferenças sazonais e espaciais na composição específica podem ser explicadas pela disponibilidade de substratos rochosos, transparência da água e proximidade com a área urbana. A maior diversidade de rodófitas e clorófitas foi observada na Ilha do Mel e a de feofíceas no Arquipélago de Currais. A menor diversidade de algas foi observada na Ilha do Farol, ponto amostral mais próximo a uma área urbana. Ceramiaceae, Rhodomelaceae e Corallinaceae foram dominantes entre Rhodophyta, Cladophoraceae e Ulvaceae entre Chlorophyta, e Dictyotaceae e Sargassaceae entre Phaeophyceae. A diversidade de algas marinhas bentônicas na costa do Paraná é menor quando comparada a outros estados brasileiros e isto está associado à menor extensão de sua linha de costa, menor disponibilidade de substratos consolidados para recrutamento e localização entre dois sistemas estuarinos (baías de Paranaguá e de Guaratuba). Os estuários aumentam consideravelmente o aporte de água continental, diminuindo a salinidade, elevando as concentrações de material particulado em suspensão e reduzindo a transparência da água. O conhecimento da diversidade algácea é fundamental para estudos de conservação, sendo que câmbios sazonais em médio e longo prazo podem estar relacionados a alterações ambientais. O indicador destas mudanças pode ser a detecção de novas ocorrências, espécies novas ou ainda introdução de espécies exóticas na área em questão, ou mesmo pela dominância de táxons oportunistas. Portanto, uma base de dados que sustente um monitoramento da biodiversidade é relevante por detectar impactos que podem alterar padrões biogeográficos das comunidades de macroalgas, principalmente em regiões com influência de atividades antrópicas, como as zonas urbanas ou áreas portuárias.
ABSTRACT
This paper is a compilation of data from investigations made with marine benthic algae from the Magellan Region that have biotechnological utilization in human consumption or medicine or as a source of phycolloids or food supplements or animal feed. The most important Rhodophyta species are: Ahnfeltia plicata (Hudson) E.M. Fries for agarose production, Gigartina skottsbergii Setchell & N.L.Gardner for carrageenan production, and Callophyllis variegata (Bory de Saint-Vincent) Kützing for human consumption. The most important Heterokontophyta species are: Macrocystis pyrifera (L.) C. Agardh, and Durvillaea antarctica (Chamisso) Hariot for human consumption, alginate production, and as biofertilizer for agricultural crops. M. pyrifera is also used as a food supplement for salmon, chickens, quails, sheep and bovines and for biofuel production.
ABSTRACT
Seaweeds are photosynthetic organisms important to their ecosystem and constitute a source of compounds with several different applications in the pharmaceutical, cosmetic and biotechnology industries, such as triacylglycerols, which can be converted to fatty acid methyl esters that make up biodiesel, an alternative source of fuel applied in economic important areas. This study evaluates the fatty acid profiles and concentrations of three Brazilian seaweed species, Hypnea musciformis (Wulfen) J.V. Lamouroux (Rhodophya), Sargassum cymosum C. Agardh (Heterokontophyta), and Ulva lactuca L. (Chlorophyta), comparing three extraction methods (Bligh & Dyer - B&D; AOAC Official Methods - AOM; and extraction with methanol and ultrasound - EMU) and two transesterification methods (7% BF3 in methanol - BF3; and 5% HCl in methanol - HCl). The fatty acid contents of the three species of seaweeds were significantly different when extracted and transesterified by the different methods. Moreover, the best method for one species was not the same for the other species. The best extraction and transesterification methods for H. musciformis, S. cymosum and U. lactuca were, respectively, AOM-HCl, B&D-BF3 and B&D-BF3/B&D-HCl. These results point to a matrix effect and the method used for the analysis of the fatty acid content of different organisms should be selected carefully.
ABSTRACT
Four extracts from the seaweed Hypnea musciformis (Wulfen in Jacq.) J.V. Lamour. (Rhodophyta), collected directly from its natural habitat or cultivated in the presence of phytohormones, were evaluated for their ability to inhibit the replication of acyclovir-resistant herpes simplex viruses types 1 (HSV-1) and 2 (HSV-2) strains. The main purpose was to determinate whether these growth conditions would affect the antiviral activity. Our results showed the possibility of improving the anti-HSV activity by using extracts from algae cultured in the presence of phytohormones.