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1.
Chemosphere ; 238: 124652, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31473524

RESUMO

This research aimed to find the best phenotype of the brown algae Fucus vesiculosus (kelp) which has the greater potential to become a sorption byproduct for Zn removal from contaminated waters. Thus, the Zn uptake capacity and sorption mechanisms of the kelp collected from the Baltic Sea shore was, for the first time, investigated under various conditions, and compared to the phenotype habiting on the Irish Sea shore. Sorption studies were performed investigating the effect of algal dosage, Zn sources as well as algal harvesting time of the year on Zn uptake capacity. The results suggested that the Baltic algae is a better bio-sorbent for Zn uptake. Sorption mechanisms were studied by employing various indirect and direct approaches, more importantly, including high resolution synchrotron X-Ray Fluorescence and X-Ray Absorption Spectroscopy (XAS) and molecular modelling (MM). The results revealed that alginate and cellulose are among the main polysaccharide bonding Zn at algal surface, via coordination with O atoms from carboxyl and hydroxyl groups. XAS results giving direct measurements of Zn bonding environment on algal surface are supported by MM outputs and suggested that Zn is surrounded by ca. 5 O atoms at interatomic distances varying from 1.94 to 2.02 Å. The results contribute to understanding sorption mechanisms which can further lead to finding the best eluent for Zn desorption from the used biomass, bio sorbent reconditioning and reuse in multiple sorption desorption cycles as well as process optimization before industrial scaling up.


Assuntos
Biodegradação Ambiental , Fucus/metabolismo , Zinco/isolamento & purificação , Absorção Fisico-Química , Alginatos/metabolismo , Biomassa , Celulose/metabolismo , Fucus/química , Reciclagem/métodos , Zinco/farmacocinética
2.
Artigo em Inglês | MEDLINE | ID: mdl-31569507

RESUMO

Alpha-cypermethrin is a synthetic pyrethroid that was extensively used for insect control, since the early 1980s. However, it is known that its presence in the environment has toxic effects on humans and aquatic life forms. For this reason, it is commendable for it to be removed completely from the contaminated environment. In this study, we evaluated the adsorption capacity of a marine alga for the removal of cypermethrin from water. The adsorption experiments were performed based on the batch equilibrium technique. The samples containing the pesticide were analyzed using gas chromatography with an electron capture detector, after liquid-liquid extraction in hexane. The results obtained from the kinetic adsorption studies showed that the equilibrium time was attained after 40 min. The adsorption parameters at equilibrium concentrations, obtained through the Langmuir, Freundlich, and Temkin models, showed that the used brown marine alga has a maximum amount of adsorbed cypermethrin of 588.24 µg/g. The correlation coefficients obtained for each model prove that the Langmuir model best fits the experimental data.


Assuntos
Recuperação e Remediação Ambiental/métodos , Fucus/metabolismo , Piretrinas/análise , Poluentes Químicos da Água/análise , Poluição Química da Água/prevenção & controle , Purificação da Água/métodos , Adsorção , Biodegradação Ambiental , Cinética
3.
Environ Pollut ; 254(Pt A): 112977, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31377326

RESUMO

Glyphosate, as a broad-spectrum herbicide, is frequently detected in water and several studies have investigated its effects on several freshwater aquatic organisms. Yet, only few investigations have been performed on marine macroalgae. Here, we studied both the metabolomics responses and the effect on primary production in the endemic brown algae Fucus virsoides exposed to different concentration (0, 0.5, 1.5 and 2.5 mg L-1) of a commercial glyphosate-based herbicide, namely Roundup®. Our results show that Roundup® significantly reduced quantum yield of photosynthesis (Fv/Fm) and caused alteration in the metabolomic profiles of exposed thalli compared to controls. Together with the decrease in the aromatic amino acids (phenylalanine and tyrosine), an increase in shikimate content was detected. The branched-amino acids differently varied according to levels of herbicide exposure, as well as observed for the content of choline, formate, glucose, malonate and fumarate. Our results suggest that marine primary producers could be largely affected by the agricultural land use, this asking for further studies addressing the ecosystem-level effects of glyphosate-based herbicides in coastal waters.


Assuntos
Fucus/metabolismo , Glicina/análogos & derivados , Herbicidas/toxicidade , Poluentes Químicos da Água/toxicidade , Agricultura , Animais , Ecossistema , Água Doce/química , Glicina/toxicidade , Metabolômica , Fenilalanina/metabolismo , Fotossíntese/efeitos dos fármacos , Ácido Chiquímico/metabolismo , Tirosina/metabolismo
4.
Environ Pollut ; 254(Pt B): 113072, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31454577

RESUMO

The viability and physiological state of brown macroalgae Fucus vesiculosus and its associated epiphytic bacteria exposed to diesel water-accommodated fraction (WAF), as well as the capacity of this association to deplete petroleum hydrocarbons (HCs) were experimentally tested. After a 6-day exposure treatment, the algal-surface associated bacteria were identified as primarily hydrocarbon-oxidising bacteria (HOB), and the algal-HOB association was able to deplete petroleum hydrocarbons from the diesel WAF by 80%. The HOB density on the algal surface exposed to diesel WAF was 350% higher compared to the control (i.e. HOB density on the algal surface exposed to ambient seawater), which suggest that they actively proliferated in the presence of hydrocarbons and most likely consumed hydrocarbons as their primary organic substrate. Exposure to diesel WAF did not affect the metabolic activity of F. vesiculosus. Higher lipid peroxidation was observed in F. vesiculosus exposed to diesel WAF while catalase concentration decreased only during the first day of exposure. Results suggest F. vesiculosus is tolerant to oil pollution and the algal-HOB association can efficiently deplete petroleum hydrocarbons in oil-contaminated seas.


Assuntos
Fucus/fisiologia , Hidrocarbonetos/metabolismo , Petróleo/metabolismo , Poluentes Químicos da Água/metabolismo , Bactérias , Biodegradação Ambiental , Fucus/metabolismo , Hidrocarbonetos/análise , Oceanos e Mares , Poluição por Petróleo/análise , Água do Mar , Alga Marinha , Água/metabolismo , Poluentes Químicos da Água/análise
5.
Mar Drugs ; 17(6)2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31167455

RESUMO

Fucus vesiculosus is an edible brown macroalga, with health benefits associated with its consumption and also a source of bioactive molecules. It is acknowledged that the biochemical composition of macroalgae changes when exposed to different environmental conditions occurring on different habitats, such as the water temperature, and light intensity. In the present study, the polar lipidome of Fucus vesiculosus was characterized for the first time using modern high-resolution HILIC-MS, and MS/MS approaches, to evaluate the phenotypic variability in two seasons of the year, e.g., winter and spring. A total of 187 molecular species were identified over eighteen classes of glycolipids, phospholipids and betaine lipids. Principal component analysis (PCA) multivariate statistical analysis and cluster analysis of polar lipid classes, polar lipid species and total fatty acids (FA) datasets, showed clustering according to the seasonal groups. While the lipid profile of Fucus vesiculosus harvested in the winter and spring yielded the same molecular species, the relative abundance of these species was significantly different. In the winter, changes were mainly due to the increased relative abundance of some molecular species of glycolipids and phospholipids, bearing octadeca(poly)enoic (18:3, 18:4) and eicosa(poly)enoic (20:4, 20:5) FA and betaine lipids species with short saturated FA (14:0) and polyunsaturated FA (PUFA). Importantly, glycolipids with n-3 PUFA and sulfolipids, have been reported to have important biological activities and therapeutic value. Overall, Fucus vesiculosus is a promising source of bioactive compounds that can be used as functional food or ingredients for human nutrition, feed, pharma, and cosmetic formulations. In this study, samples harvested in the winter season maximized yields of these bioactive components, when compared with samples harvested in the spring.


Assuntos
Fucus/química , Lipídeos/química , Estações do Ano , Fucus/metabolismo , Lipídeos/análise , Espectrometria de Massas , Compostos Fitoquímicos/química
6.
Sci Total Environ ; 650(Pt 2): 2364-2373, 2019 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-30292992

RESUMO

Volatile methylsiloxanes (VMSs) are massively produced chemicals that comprise a wide range of industrial and household applications. The presence of cyclic and linear VMSs in several environmental matrices and ecosystems indicates persistence associated with a potential of (bio)accumulation and food web transfer with possible toxicological effects. Due to the high anthropogenic pressure in its vicinities particularly in summer, coastal areas in Southern European countries are potential hotspots for the presence of VMSs. The massive afflux of tourists and consequent increase of the use of personal care products (PCPs) with VMSs in their formulations highlight the importance of VMSs assessment in such areas. In this study, different species of marine vegetation (algae and seaweed) were collected in three different geographical areas, covering the Atlantic Ocean (North coast of Portugal), as well as the Mediterranean Sea (coasts of the Region of Murcia, Spain and of the city of Marseille, France). Samples were analysed for the determination of 4 cyclic (D3, D4, D5, D6) and 3 linear (L3, L4, L5) VMSs employing a QuEChERS extraction methodology, followed by gas chromatography/mass spectrometry (GC/MS) quantification. VMSs were detected in 92% of the 74 samples analysed, with the sum of the concentrations per sample ranging from below the limit of detection (LOD) to 458 ±â€¯26 ng·g-1dw (dry weight). A strong predominance of cyclic VMSs over linear ones was verified in almost all samples studied, with D5 and D6 found at higher concentrations. Seasonal variation was also assessed and despite higher levels of VMSs being identified mostly in summer months, clear seasonal trends were not perceived. It was also noted that generally the higher incidence of VMSs occurred in samples from urban and industrialized areas or in the vicinities of WWTPs, suggesting a direct input from these sources in the levels of siloxanes observed.


Assuntos
Alismatales/metabolismo , Exposição Ambiental , Alga Marinha/metabolismo , Siloxanas/metabolismo , Compostos Orgânicos Voláteis/metabolismo , Poluentes Químicos da Água/metabolismo , Oceano Atlântico , Monitoramento Ambiental , França , Fucus/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Mar Mediterrâneo , Porphyra/metabolismo , Portugal , Espanha , Ulva/metabolismo
7.
Sci Total Environ ; 648: 1201-1209, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30340265

RESUMO

In the context of developing the circular economy that enables a more sustainable use of the available resources and minimum waste generation, marine macroalgae have attracted the attention of researchers and industry due to its potential as a renewable resource. The current work aims to contribute to the design of a complete biorefinery processing, using Fucus spiralis seaweed (brown division) as starting material, and to determine the potential of the derived waste as biosorbent of heavy metals in aqueous solution. The macroalgae waste was obtained after the sequential separation of polyphenols, fucoidan and alginate extracts from F. spiralis. The capacity of F. spiralis waste for Pb(II) removal was successfully tested through biosorption tests. The uptake of Pb(II) was found to be very fast (few hours to achieve equilibrium). Tests performed with an initial metal concentration of 20 mg/L established the best adsorbent dosage (0.50 g/L) and an optimum pH of 4.5. In these conditions, lead was almost completely removed from the aqueous solution. Maximum adsorption capacity predicted by Langmuir model was 132 ±â€¯14 mg/g (pH 4.5 ±â€¯0.5, 20 °C). Desorption studies were conducted with different possible eluents. The best results were obtained with EDTA 0.1 mol/L, generating a 95 ±â€¯4% desorption. F. spiralis biomass can therefore be submitted to a complete biorefinery processing and design in the attempt to fulfil the "zero-waste" concept.


Assuntos
Recuperação e Remediação Ambiental/métodos , Fucus/metabolismo , Chumbo/metabolismo , Poluentes Químicos da Água/metabolismo , Adsorção , Biodegradação Ambiental , Biomassa , Alga Marinha/metabolismo
8.
Planta ; 249(2): 377-391, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30209618

RESUMO

MAIN CONCLUSION: Tight regulation of intra-thallus metabolite distribution in Fucus vesiculosus in late summer reveals the complex biochemical processes complying with reproduction and the preparation to the dark season. We used inductively coupled plasma atomic emission spectroscopy to study the tissue-specific elemental composition, and gas chromatography coupled to mass spectrometry to study the distribution of small-molecular weight primary and secondary metabolites of the brown alga Fucus vesiculosus thalli in the reproductive phase. Beyond general physiological requirements, the observed distribution of the analysed nutrients was also found to depend on characteristics related to the season of harvesting, i.e., the reproductive period. However, a particular curious result was the high metabolic activity found in the stipe of the plant. In conclusion, our data not only provide valuable information for industrial use of fucoids targeting specific algal ingredients, but also give highly interesting insights in the multifaceted system of intra-thallus biochemical interactions during reproduction of the brown algae.


Assuntos
Fucus/metabolismo , Metabolômica/métodos , Espectrofotometria Atômica
9.
Mar Drugs ; 16(12)2018 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-30551573

RESUMO

The metabolism of seaweeds depends on environmental parameters, the availability of nutrients, and biotic/abiotic stresses; therefore, their chemical composition fluctuates throughout the year. This study investigated seasonal variations in the metabolome of the Baltic Sea brown alga Fucus vesiculosus and its potential relation to the bioactivity profile. By using a definitive screening design (DSD) combined with pressurised liquid extraction (PLE), an optimised protocol was developed to extract algal biomass monthly for a full calendar year. An untargeted metabolomics approach using ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MSn)-based molecular networking and manual dereplication was employed. The extracts were simultaneously screened for their in vitro antimicrobial, anticancer/apoptotic, and free radical scavenging activities. 44 compounds were putatively dereplicated in the metabolome. Many compounds were found to vary with the sampling month; phlorotannin total ion count (TIC) was highest in summer, whilst chlorophylls, lipids, and carotenoids peaked in winter and spring. The greatest radical scavenging and apoptotic activities against pancreas cancer cells observed in the summer months were attributed to high phlorotannin TIC. Methicillin-resistant Staphylococcus aureus (MRSA) inhibitory activity was produced year-round without a clear seasonal trend. This is the first study applying DSD-based optimised PLE extraction combined with a metabolome analysis of F. vesiculosus for the identification of seasonal variations in both metabolome and bioactivity.


Assuntos
Fucus/metabolismo , Metaboloma , Extratos Vegetais/farmacologia , Estações do Ano , Alga Marinha/metabolismo , Células A549 , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/metabolismo , Produtos Biológicos/farmacologia , Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Ensaios de Seleção de Medicamentos Antitumorais , Depuradores de Radicais Livres/química , Depuradores de Radicais Livres/isolamento & purificação , Depuradores de Radicais Livres/metabolismo , Depuradores de Radicais Livres/farmacologia , Fucus/química , Humanos , Extração Líquido-Líquido/instrumentação , Extração Líquido-Líquido/métodos , Metabolômica/instrumentação , Metabolômica/métodos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Pressão , Alga Marinha/química
10.
Sci Rep ; 8(1): 16824, 2018 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-30429500

RESUMO

Isopods of the genus Idotea have an unusual ability to feed on algae containing high amounts of chemical defense molecules, such as species of the genera Fucus and Ulva. In this study, we compared gene expression patterns of Idotea balthica individuals fed with Fucus vesiculosus to individuals fed with Ulva lactuca. We generated the first-ever transcriptome assembly for this species, and found 3,233 differentially expressed genes across feeding regimes. However, only a handful of biological functions were enriched with regard to differentially expressed genes, the most notable being "alkaloid metabolic process". Within this category, we found eight differentially expressed cytochrome P450 (CYP) unigenes, all of which had a higher expression in the U. lactuca diet treatment. A phylogenetic analysis showed that the differentially expressed CYP genes are closely related to a CYP gene described from the hepatopancreas of the spiny lobster Panulirus argus, and we hypothesize that these transcripts are involved in metabolite detoxification. This is a first step in the understanding of this algae-grazer interaction, and will form a basis for future work to characterize cytochrome P450 functioning in marine crustaceans.


Assuntos
Sistema Enzimático do Citocromo P-450/análise , Fucus/metabolismo , Isópodes/enzimologia , Transcriptoma , Ulva/metabolismo , Animais , Dieta , Inativação Metabólica , Isópodes/metabolismo , Palinuridae/enzimologia , Filogenia , Metabolismo Secundário
11.
PLoS One ; 13(9): e0203666, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30212558

RESUMO

The nature of species distribution boundaries is a key subject in ecology and evolution. Edge populations are potentially more exposed to climate-related environmental pressures. Despite research efforts, little is known about variability in fitness-related traits in leading (i.e., colder, high latitude) versus trailing (i.e., warmer, low latitude) edge populations. We tested whether the resilience, i.e. the resistance and recovery, of key traits differs between a distributional cold (Greenland) and warm (Portugal) range edge population of two foundation marine macrophytes, the intertidal macroalga Fucus vesiculosus and the subtidal seagrass Zostera marina. The resistance and recovery of edge populations to elevated seawater temperatures was compared under common experimental conditions using photosynthetic efficiency and expression of heat shock proteins (HSP). Cold and warm edge populations differed in their response, but this was species specific. The warm edge population of F. vesiculosus showed higher thermal resistance and recovery whereas the cold leading edge was less tolerant. The opposite was observed in Z. marina, with reduced recovery at the warm edge, while the cold edge was not markedly affected by warming. Our results confirm that differentiation of thermal stress responses can occur between leading and trailing edges, but such responses depend on local population traits and are thus not predictable just based on thermal pressures.


Assuntos
Fucus/crescimento & desenvolvimento , Zosteraceae/crescimento & desenvolvimento , Proteínas de Algas/metabolismo , Fucus/metabolismo , Expressão Gênica , Groenlândia , Proteínas de Choque Térmico/metabolismo , Fotossíntese/fisiologia , Portugal , Estresse Fisiológico , Temperatura , Zosteraceae/metabolismo
12.
Food Chem ; 265: 233-241, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29884379

RESUMO

The anti-allergenicity of phlorotannin-targeted extracts from four edible seaweed species of Fucus genus was evaluated herein for the first time. Extracts were able to act upon cellular events triggered by immunological reaction (IgE/antigen), and on cellular events downstream the Ca2+ influx caused by a chemical stimulus (calcium ionophore A23187), preventing degranulation of RBL-2H3 cells. Furthermore, a dose-dependent behaviour towards allergy-related enzymatic systems was observed for all the phlorotannin extracts. Linear correlations were found between reduction of the allergic mediators released and the total phlorotannin content, as well as between the enzyme inhibition and the amount of phlorotannins in the extracts. These results point to a multi-target anti-allergic capacity of phlorotannin-targeted extracts, which displayed effects on different critical steps of the allergic response, contributing to the valorisation of Fucus spp. both as food and for nutraceutical applications.


Assuntos
Antialérgicos/farmacologia , Degranulação Celular/efeitos dos fármacos , Fucus/química , Alga Marinha/química , Taninos/farmacologia , Animais , Antialérgicos/química , Antialérgicos/uso terapêutico , Linhagem Celular , Fucus/metabolismo , Histamina/metabolismo , Hialuronoglucosaminidase/antagonistas & inibidores , Hialuronoglucosaminidase/metabolismo , Hipersensibilidade/imunologia , Hipersensibilidade/metabolismo , Hipersensibilidade/prevenção & controle , Imunoglobulina E/imunologia , Imunoglobulina E/metabolismo , Mastócitos/citologia , Mastócitos/efeitos dos fármacos , Mastócitos/metabolismo , Extratos Vegetais/química , Alga Marinha/metabolismo , Taninos/química , Taninos/uso terapêutico
13.
Carbohydr Polym ; 193: 189-195, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29773371

RESUMO

Enzymatic depolymerization of fucoidans attracts many researchers due to the opportunity of obtaining standardized fucoidan fragments. Fucoidanase catalyzes the cleavage of fucoidan from Fucus evanescens (FeF) to form low molecular weight products (LMP) and a polymeric fraction (HMP) with 50.8 kDa molecular weight and more than 50% yield. NMR spectroscopy shows that the HMP fraction has regular structure and consists of a repeating fragment [→3)-α-l-Fucp2,4OSO3--(1 → 4)-α-l-Fucp2,4OSO3--(1 → 4)-α-l-Fucp2OSO3--(1→]n. The anticancer effects of FeF fucoidan and its derivative (HMP) were studied in vitro on colon cancer cells HCT-116, HT-29, and DLD-1. The anticancer activity of the HMP fraction was found to be slightly lower than that of the FeF fucoidan. Research and practical applications of the enzyme include modification of native fucoidans for purposes of regular and easier characterized derivatives acquisition.


Assuntos
Antineoplásicos/farmacologia , Fucus/química , Fucus/enzimologia , Hidrolases/metabolismo , Polissacarídeos/farmacologia , Antineoplásicos/química , Antineoplásicos/metabolismo , Biocatálise , Configuração de Carboidratos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Fucus/metabolismo , Humanos , Hidrolases/química , Polissacarídeos/química , Polissacarídeos/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Relação Estrutura-Atividade , Células Tumorais Cultivadas
14.
Int J Biol Macromol ; 112: 667-674, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29408614

RESUMO

Fucoidans are complex sulfated polysaccharides that have a wide range of biological activities. Previously, we reported the various effects of Fucus vesiculosus fucoidan on tyrosinase and B16 melanoma cells. In this study, to identify fucoidan-targeted proteins in B16 melanoma cells, we performed a proteomics study and integrated enzyme kinetics. We detected 19 candidate proteins dysregulated by fucoidan treatment. Among the probed proteins, the enzyme kinetics of two candidate enzymes, namely lactate dehydrogenase (LDH) as an upregulated protein and superoxide dismutase (SOD) as a downregulated enzyme, were determined. The enzyme kinetics results showed that Fucus vesiculosus fucoidan significantly inhibited LDH catalytic function while it did not affect SOD activity even at a high dose, while only slightly decreased activity (up to 10%) at a low dose. Based on our previous and present observations, fucoidan could inhibit B16 melanoma cells growth via regulating proteins/enzymes expression levels such as LDH and SOD known as cell survival biomarkers. Interestingly, both expression level and enzyme catalytic activity of LDH were regulated by fucoidan, which could directly induce the apoptotic effect on B16 melanoma cells along with SOD downregulation. This study highlights how combining proteomics with enzyme kinetics can yield valuable insights into fucoidan targets.


Assuntos
Fucus/metabolismo , Melanoma Experimental/enzimologia , Polissacarídeos/farmacologia , Proteômica/métodos , Animais , Eletroforese em Gel Bidimensional , Ensaios Enzimáticos , Cinética , L-Lactato Desidrogenase/metabolismo , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos , Proteínas de Neoplasias/metabolismo , Sargassum/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Superóxido Dismutase/metabolismo
15.
Environ Geochem Health ; 40(2): 683-691, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28866841

RESUMO

Seaweed baths containing Fucus serratus Linnaeus are a rich source of iodine which has the potential to increase the urinary iodide concentration (UIC) of the bather. In this study, the range of total iodine concentration in seawater (22-105 µg L-1) and seaweed baths (808-13,734 µg L-1) was measured over 1 year. The seasonal trend shows minimum levels in summer (May-July) and maximum in winter (November-January). The bathwater pH was found to be acidic, average pH 5.9 ± 0.3. An in vivo study with 30 volunteers was undertaken to measure the UIC of 15 bathers immersed in the bath and 15 non-bathers sitting adjacent to the bath. Their UIC was analysed pre- and post-seaweed bath and corrected for creatinine concentration. The corrected UIC of the population shows an increase following the seaweed bath from a pre-treatment median of 76 µg L-1 to a post-treatment median of 95 µg L-1. The pre-treatment UIC for both groups did not indicate significant difference (p = 0.479); however, the post-treatment UIC for both did (p = 0.015) where the median bather test UIC was 86 µg L-1 and the non-bather UIC test was 105 µg L-1. Results indicate the bath has the potential to increase the UIC by a significant amount and that inhalation of volatile iodine is a more significant contributor to UIC than previously documented.


Assuntos
Banhos , Climatoterapia , Fucus/metabolismo , Iodo/metabolismo , Alga Marinha , Adulto , Idoso , Creatinina/urina , Humanos , Concentração de Íons de Hidrogênio , Iodetos/urina , Pessoa de Meia-Idade , Estações do Ano , Volatilização , Adulto Jovem
16.
J Phycol ; 54(1): 114-125, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29130494

RESUMO

The biogeochemistry of iodine in temperate coastal ecosystems is largely mediated by macroalgae, which act as a major biological sink and source of iodine. Their capacity to accumulate, retain and release iodine has been associated with abiotic and biotic stressors, but quantitative information is limited. We evaluated the seasonal iodine retention capacity of eleven macroalgal species belonging to different systematic groups, collected from two sites in Ireland. Iodine accumulation and retention were then further quantified in Fucus vesiculosus and Laminaria digitata in relation to I- concentrations in seawater and temperature. In general, iodine contents were ~101 -102  µmol · (g dw)-1 for Laminariales, 100 -101  µmol · (g dw)-1 for Fucales, 10-1 -100  µmol · (g dw)-1 for Rhodophyta, and 10-1  µmol · (g dw)-1 for Chlorophyta. Typically, algal iodine contents were above average in winter and below average in summer. Iodine accumulation in F. vesiculosus and L. digitata depended on I- availability and followed the Michaelis-Menten kinetic. The ratio of maximum accumulation rate to half accumulation coefficient (ρmax : Kt ) was 2.4 times higher for F. vesiculosus than for L. digitata, suggesting that F. vesiculosus was more efficient in iodine accumulation. Both species exhibited a temperature-dependent net loss of iodine, and only an exposure to sufficient external I- concentrations compensated for this loss. This study revealed that both environmental (e.g., I- in seawater, temperature) and organismal (e.g., the status of the iodine storage pool) variables determine retention and variability in iodine in temperate seaweeds.


Assuntos
Fucus/metabolismo , Iodo/metabolismo , Laminaria/metabolismo , Alga Marinha/metabolismo , Irlanda , Cinética , Feófitas/metabolismo , Rodófitas/metabolismo , Especificidade da Espécie , Ulva/metabolismo
17.
Molecules ; 22(9)2017 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-28891948

RESUMO

Brown algae have an important role in marine environments. With respect to their broad distribution and importance for the environment and human use, brown algae of the order Fucales in particular became a model system for physiological and ecological studies. Thus, several fucoids have been extensively studied for their composition on the molecular level. However, research of fucoid physiology and biochemistry so far mostly focused on the adult algae, so a holistic view on the development of these organisms, including the crucial first life stages, is still missing. Therefore, we employed non-targeted metabolite profiling by gas chromatography coupled to mass spectrometry to create a non-biased picture of the early development of the fucoid alga Fucus vesiculosus. We found that embryogenic physiology was mainly dominated by a tight regulation of carbon and energy metabolism. The first dramatic changes of zygote metabolism started within 1 h after fertilization, while metabolism of 6-9 days old embryos appeared already close to that of an adult alga, indicated by the intensive production of secondary metabolites and accumulation of mannitol and citric acid. Given the comprehensive description and analysis we obtained in our experiments, our results exhibit an invaluable resource for the design of further experiments related to physiology of early algal development.


Assuntos
Desenvolvimento Embrionário/fisiologia , Metabolismo Energético/fisiologia , Fucus/metabolismo , Metaboloma/fisiologia , Feófitas/metabolismo , Carbono/metabolismo , Ácido Cítrico/metabolismo , Fucus/crescimento & desenvolvimento , Manitol/metabolismo , Feófitas/crescimento & desenvolvimento , Análise de Componente Principal , Metabolismo Secundário/fisiologia , Zigoto/crescimento & desenvolvimento , Zigoto/metabolismo
18.
Bull Environ Contam Toxicol ; 99(3): 372-379, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28685221

RESUMO

In this study we compared the accumulation of eight metals and two metalloids in the growing tips and the remaining shoot tissue of three species of brown seaweeds commonly used in biomonitoring studies (Fucus ceranoides, Fucus spiralis and Ascophyllum nodosum). Regression analysis of the data obtained showed that there was no statistically significant difference in accumulation in numerous cases; although most of the relationships were significant, many of the coefficients of determination were low. However, the concentrations of Mn and Zn in the growing tips were closely related to the concentrations in the rest of the tissue in all three species, possibly due to redistribution of these elements. Interspecies differences in bioconcentration of the elements may be partly explained by differences in the relative growth rates.


Assuntos
Monitoramento Ambiental , Metais/metabolismo , Alga Marinha/metabolismo , Poluentes Químicos da Água/metabolismo , Ascophyllum/metabolismo , Fucus/metabolismo
19.
Chemosphere ; 171: 208-222, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28024206

RESUMO

Results of 7-days exposure to metals, using environmentally realistic conditions, evidenced the high potential of living Fucus vesiculosus to remove Pb, Hg and Cd from contaminated salt waters. For different contamination scenarios (single- and multi-contamination), ca 450 mg L-1 (dry weight), enable to reduce the concentrations of Pb in 65%, of Hg in 95% and of Cd between 25 and 76%. Overall, bioconcentration factors ranged from 600 to 2300. Elovich kinetic model described very well the bioaccumulation of Pb and Cd over time, while pseudo-second-order model adjusted better to experimental data regarding Hg. F. vesiculosus showed different affinity toward studied metals, following the sequence order: Hg > Pb > Cd. Analysis of metal content in the macroalgae after bioaccumulation, proved that all metal removed from solution was bound to the biomass. Depuration experiments reveled no significant loss of metal back to solution. Exposure to contaminants only adversely affected the organism's growth for the highest concentrations of Cd and Pb. Findings are an important contribute for the development of remediation biotechnologies for confined saline waters contaminated with trace metal contaminants, more efficient and with lower costs than the traditional treatment methods.


Assuntos
Cádmio/farmacologia , Fucus/crescimento & desenvolvimento , Chumbo/farmacologia , Mercúrio/farmacologia , Poluentes da Água/farmacologia , Biomassa , Cádmio/análise , Fucus/efeitos dos fármacos , Fucus/metabolismo , Chumbo/análise , Mercúrio/análise , Poluentes da Água/análise
20.
Ecol Appl ; 27(2): 669-681, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27875010

RESUMO

Urbanization of coastlines is leading to increased introduction of nutrients from the terrestrial environment to nearshore habitats. While such nutrient influxes can be detrimental to coastal marine organisms due to increased eutrophication and subsequent reduced oxygen, they could also have positive effects (i.e., increased food availability) on species that are nitrogen-limited such as macroalgae. Nutrient enrichment in this environment thus has the potential to counteract some of the negative impacts of increasing temperatures, at least for some species. Characterizing the physiological response of organisms to simultaneous changes in multiple drivers such as these is an important first step in predicting how global climate change may lead to ecological responses at more local levels. We evaluated how nutrient enrichment (i.e., nitrogen availability) affected the growth of Fucus vesiculosus, a foundational macroalgal species in the North Atlantic rocky intertidal zone, and found that nutrient-enriched algal blades showed a significant increase in tissue growth compared to individuals grown under ambient conditions. We further quantified net photosynthesis by ambient and nutrient-enriched tissues at saturating irradiance over a range of temperature conditions (6-30°C). Respiration was unaffected by nutrient treatment; however, there was a significant increase in photosynthetic oxygen production for nutrient-enriched tissue compared to ambient, but only at elevated (≥18°C) temperatures. This study contributes to a growing body of literature showing the complexity of responses to changes in multiple drivers, and highlights the importance of studying the impacts of global climate change within the context of more local environmental conditions.


Assuntos
Mudança Climática , Fucus/crescimento & desenvolvimento , Fucus/metabolismo , Nitrogênio/metabolismo , Fotossíntese , Temperatura Alta/efeitos adversos , Massachusetts , Nutrientes/metabolismo , Alga Marinha/crescimento & desenvolvimento , Alga Marinha/metabolismo
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