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1.
Glob Chang Biol ; 30(4): e17249, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38572713

RESUMO

Warming as well as species introductions have increased over the past centuries, however a link between cause and effect of these two phenomena is still unclear. Here we use distribution records (1813-2023) to reconstruct the invasion histories of marine non-native macrophytes, macroalgae and seagrasses, in the Mediterranean Sea. We defined expansion as the maximum linear rate of spread (km year-1) and the accumulation of occupied grid cells (50 km2) over time and analyzed the relation between expansion rates and the species' thermal conditions at its native distribution range. Our database revealed a marked increase in the introductions and spread rates of non-native macrophytes in the Mediterranean Sea since the 1960s, notably intensifying after the 1990s. During the beginning of this century species velocity of invasion has increased to 26 ± 9 km2 year-1, with an acceleration in the velocity of invasion of tropical/subtropical species, exceeding those of temperate and cosmopolitan macrophytes. The highest spread rates since then were observed in macrophytes coming from native regions with minimum SSTs two to three degrees warmer than in the Mediterranean Sea. In addition, most non-native macrophytes in the Mediterranean (>80%) do not exceed the maximum temperature of their range of origin, whereas approximately half of the species are exposed to lower minimum SST in the Mediterranean than in their native range. This indicates that tropical/subtropical macrophytes might be able to expand as they are not limited by the colder Mediterranean SST due to the plasticity of their lower thermal limit. These results suggest that future warming will increase the thermal habitat available for thermophilic species in the Mediterranean Sea and continue to favor their expansion.


Assuntos
Espécies Introduzidas , Alga Marinha , Mar Mediterrâneo , Ecossistema , Temperatura
2.
Anal Bioanal Chem ; 416(11): 2871-2882, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38581531

RESUMO

Antarctic seaweeds are vital components of polar marine ecosystems, playing a crucial role in nutrient cycling and supporting diverse life forms. The sulfur content in these organisms is particularly interesting due to its implication in biogeochemical processes and potential impacts on local and global environmental systems. In this study, we present a comprehensive characterization of seaweed collected in the Antarctic in terms of their total sulfur content and its distribution among different classes of species, including thiols, using various methods and high-sensitivity techniques. The data presented in this paper are unprecedented in the scientific literature. These methods allowed for the determination of total sulfur content and the distribution of sulfur compounds in different fractions, such as water-soluble and proteins, as well as the speciation of sulfur compounds in these fractions, providing valuable insights into the chemical composition of these unique marine organisms. Our results revealed that the total sulfur concentration in Antarctic seaweeds varied widely across different species, ranging from 5.5 to 56 g kg-1 dry weight. Furthermore, our investigation into the sulfur speciation revealed the presence of various sulfur compounds, including sulfate, and some thiols, which were quantified in all ten seaweed species evaluated. The concentration of these individual sulfur species also displayed considerable variability among the studied seaweeds. This study provides the first in-depth examination of total sulfur content and sulfur speciation in brown and red Antarctic seaweeds.


Assuntos
Alga Marinha , Alga Marinha/química , Regiões Antárticas , Peso Molecular , Ecossistema , Enxofre/metabolismo , Compostos de Enxofre/metabolismo , Verduras , Compostos de Sulfidrila/metabolismo
3.
Nutrients ; 16(7)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38613074

RESUMO

The influence of iodine-rich foods on thyroid cancer (TC) risk remains inadequately understood. Therefore, we aimed to comprehensively investigate the relationship between three iodine-rich food groups and TC prevalence using extensive data from a large Korean population. We assessed the dietary intake of 169,057 participants in the Korean Genome and Epidemiology Study (2004-2013) using a food frequency questionnaire. The top-three iodine-rich food groups (including egg, seaweed, and dairy) were selected based on Korean dietary reference intakes and categorized by weekly consumption frequency. We conducted multiple logistic regression models to examine the relationship between food consumption and TC prevalence. After adjusting for confounding factors, higher seaweed consumption (>5 times/week) was significantly associated with lower TC prevalence (odds ratio [OR], 95% confidence interval [CI] = 0.42, 0.32-0.56, p-value < 0.001). In contrast, compared with moderate dairy consumption (3-4 times/week), lower dairy product intake (<1 time/week) was associated with higher TC prevalence (OR, 95% CI = 1.32, 1.05-1.67, p-value = 0.017). Our findings suggest that sufficient seaweed consumption may offer protection against TC, and incorporating dairy products into the diet may lower TC incidence in the Korean population. The most significant limitations of our study are the absence of 24 h urine samples for iodine status assessment and the lack of clinical data on the diagnosis of thyroid cancer.


Assuntos
Iodo , Alga Marinha , Neoplasias da Glândula Tireoide , Humanos , Neoplasias da Glândula Tireoide/epidemiologia , Neoplasias da Glândula Tireoide/etiologia , Povo Asiático , Razão de Chances
4.
Planta ; 259(5): 111, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578466

RESUMO

MAIN CONCLUSION: The combined photoinhibitory and PSII-reaction centre quenching against light stress is an important mechanism that allows the green macroalga Ulva rigida to proliferate and form green tides in coastal ecosystems. Eutrophication of coastal ecosystems often stimulates massive and uncontrolled growth of green macroalgae, causing serious ecological problems. These green tides are frequently exposed to light intensities that can reduce their growth via the production of reactive oxygen species (ROS). To understand the physiological and biochemical mechanisms leading to the formation and maintenance of green tides, the interaction between inorganic nitrogen (Ni) and light was studied. In a bi-factorial physiological experiment simulating eutrophication under different light levels, the bloom-forming green macroalga Ulva rigida was exposed to a combination of ecologically relevant nitrate concentrations (3.8-44.7 µM) and light intensities (50-1100 µmol photons m-2 s-1) over three days. Although artificial eutrophication (≥ 21.7 µM) stimulated nitrate reductase activity, which regulated both nitrate uptake and vacuolar storage by a feedback mechanism, nitrogen assimilation remained constant. Growth was solely controlled by the light intensity because U. rigida was Ni-replete under oligotrophic conditions (3.8 µM), which requires an effective photoprotective mechanism. Fast declining Fv/Fm and non-photochemical quenching (NPQ) under excess light indicate that the combined photoinhibitory and PSII-reaction centre quenching avoided ROS production effectively. Thus, these mechanisms seem to be key to maintaining high photosynthetic activities and growth rates without producing ROS. Nevertheless, these photoprotective mechanisms allowed U. rigida to thrive under the contrasting experimental conditions with high daily growth rates (12-20%). This study helps understand the physiological mechanisms facilitating the formation and persistence of ecologically problematic green tides in coastal areas.


Assuntos
Clorófitas , 60578 , Alga Marinha , Ulva , Ecossistema , Nitratos , Espécies Reativas de Oxigênio , Nitrogênio
5.
Sci Total Environ ; 927: 172272, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38583626

RESUMO

To combat with climate change, most countries have set carbon neutrality target. However, our understanding on carbon removal, release and sequestration by mariculture remains unclear. Here, carbon removal, release and sequestration by maricultured seaweeds, shellfish and fish in Shandong Province during 2003-2022 were assessed using a comprehensive method that considers the processes of biological metabolism, seawater chemistry and carbon footprint. Saccharina japonica productivity has been largely enhanced since 2014, resulting in increased production and CO2 removal and sequestration. Seaweeds removed 172 Gg C and sequestered 62 Gg C in 2022. CO2 removal and release by shellfish demonstrated a slow increase trend, ranging from 231 to 374 Gg C yr-1 and 897 to 1438 Gg C yr-1 during 2003-2022, respectively. Contrary to seaweed and shellfish, maricultured fish added CO2 to seawater due to the use of feeds. The added CO2 by fish culture achieved the peak of 60 Gg C in 2011 and decreased to 25 Gg C in 2022. Most of this added CO2 was released to atmosphere by microbial mineralization and it was in the range of 21-52 Gg C yr-1 during 2003-2022. After summing up the contribution of seaweeds, shellfish and fish, both total CO2 removal (from 110 to 259 Gg C yr-1) and total CO2 release (from 929 to 1429 Gg C yr-1) increased remarkably during the past 20 years. To neutralize CO2 release by shellfish and fish, Pyropia yezoensis needs the largest culture area (1.65 ± 0.15 × 106 ha) while Gracilariopsis lemaneiformis requires the smallest area (0.11 ± 0.03 × 106 ha). In addition, there are enough available areas for culturing G. lemaneiformis, Ulva prolifera and Sargassum fusifarme to neutralize total CO2 emission in Shandong Province. This study elucidates carbon removal, release and sequestration capacities of mariculture and indicates that seaweed culture has a tremendous potential to achieve carbon neutrality target in Shandong.


Assuntos
Aquicultura , Sequestro de Carbono , China , Alga Marinha/metabolismo , Dióxido de Carbono/análise , Mudança Climática , Água do Mar/química , Animais , Carbono/metabolismo , Carbono/análise , Frutos do Mar , Peixes/metabolismo , Monitoramento Ambiental
6.
Environ Microbiol ; 26(4): e16620, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38627038

RESUMO

Actinomycetota, associated with macroalgae, remains one of the least explored marine niches. The secondary metabolism of Actinomycetota, the primary microbial source of compounds relevant to biotechnology, continues to drive research into the distribution, dynamics, and metabolome of these microorganisms. In this study, we employed a combination of traditional cultivation and metagenomic analysis to investigate the diversity of Actinomycetota in two native macroalgae species from the Portuguese coast. We obtained and taxonomically identified a collection of 380 strains, which were distributed across 12 orders, 15 families, and 25 genera affiliated with the Actinomycetia class, with Streptomyces making up approximately 60% of the composition. Metagenomic results revealed the presence of Actinomycetota in both Chondrus crispus and Codium tomentosum datasets, with relative abundances of 11% and 2%, respectively. This approach identified 12 orders, 16 families, and 17 genera affiliated with Actinomycetota, with minimal overlap with the cultivation results. Acidimicrobiales emerged as the dominant actinobacterial order in both macroalgae, although no strain affiliated with this taxonomic group was successfully isolated. Our findings suggest that macroalgae represent a hotspot for Actinomycetota. The synergistic use of both culture-dependent and independent approaches proved beneficial, enabling the identification and recovery of not only abundant but also rare taxonomic members.


Assuntos
Actinobacteria , Clorófitas , Alga Marinha , Humanos , Alga Marinha/microbiologia , Portugal , Bactérias
7.
Microb Ecol ; 87(1): 61, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38662080

RESUMO

Emissions from transportation and industry primarily cause global warming, leading to floods, glacier melt, and rising seas. Widespread greenhouse gas emissions and resulting global warming pose significant risks to the environment, economy, and society. The need for alternative fuels drives the development of third-generation feedstocks: microalgae, seaweed, and cyanobacteria. These microalgae offer traits like rapid growth, high lipid content, non-competition with human food, and growth on non-arable land using brackish or waste water, making them promising for biofuel. These unique phototrophic organisms use sunlight, water, and carbon dioxide (CO2) to produce biofuels, biochemicals, and more. This review delves into the realm of microalgal biofuels, exploring contemporary methodologies employed for lipid extraction, significant value-added products, and the challenges inherent in their commercial-scale production. While the cost of microalgae bioproducts remains high, utilizing wastewater nutrients for cultivation could substantially cut production costs. Furthermore, this review summarizes the significance of biocircular economy approaches, which encompass the utilization of microalgal biomass as a feed supplement and biofertilizer, and biosorption of heavy metals and dyes. Besides, the discussion extends to the in-depth analysis and future prospects on the commercial potential of biofuel within the context of sustainable development. An economically efficient microalgae biorefinery should prioritize affordable nutrient inputs, efficient harvesting techniques, and the generation of valuable by-products.


Assuntos
Biocombustíveis , Biomassa , Microalgas , Microalgas/metabolismo , Microalgas/crescimento & desenvolvimento , Cianobactérias/metabolismo , Alga Marinha/metabolismo , Dióxido de Carbono/metabolismo
8.
Carbohydr Polym ; 333: 121962, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38494219

RESUMO

Ulva are hardy green seaweeds that contain the sulfated polysaccharide ulvan and grow in two distinct morphologies: foliose and tubular. The authors hypothesise that ulvan from tubular species are more structurally complex than ulvans from foliose species. Herein, using standardised methods, the glycosyl linkage positions and sulfate ester substitutions of constituent monosaccharides of ulvan isolated from foliose (U. lacinulata and U. stenophylloides) and tubular (U. prolifera and U. ralfsii) species of Ulva were investigated. Comparison of native ulvans with 80 and 100 °C desulfated counterparts indicated that 4-linked rhamnose is predominantly 3-O-sulfated in all four ulvans. Ulvans from the foliose species predominantly contained →3,4)-Rhap-(1→, →4)-GlcAp-(1→ and →4)-IdoAp-(1→, collectively accounting for 67 to 81 mol% of the total linkages. In contrast, these same linkages in ulvans from the tubular species only collectively accounted for 29 to 36 mol%. Instead, ulvan from tubular species contained a combination of →2,3,4)-Rhap-(1→, terminal Rhap-(1→, →4)-GlcAp-(1→, →4)-Xylp-(1→, and/or →4)-Galp-(1→ in high proportions; some of the latter three residues were also likely O-2 sulfated. The results presented here suggest that ulvan from foliose species are predominantly unbranched polysaccharides composed of repeat disaccharides while ulvans from tubular species contain a greater diversity of branch and sulfate substitution locations.


Assuntos
Alga Marinha , Ulva , Ulva/química , Polissacarídeos/química , Sulfatos/química
9.
Mar Drugs ; 22(3)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38535456

RESUMO

Floridoside is a galactosyl-glycerol compound that acts to supply UDP-galactose and functions as an organic osmolyte in response to salinity in Rhodophyta. Significantly, the UDP-galactose pool is shared for sulfated cell wall galactan synthesis, and, in turn, affected by thallus development alongside carposporogenesis induced by volatile growth regulators, such as ethylene and methyl jasmonate, in the red seaweed Grateloupia imbricata. In this study, we monitored changes in the floridoside reservoir through gene expression controlling both the galactose pool and glyceride pool under different reproductive stages of G. imbricata and we considered changing salinity conditions. Floridoside synthesis was followed by expression analysis of galactose-1-phosphate uridyltransferase (GALT) as UDP-galactose is obtained from UDP-glucose and glucose-1P, and through α-galactosidase gene expression as degradation of floridoside occurs through the cleavage of galactosyl residues. Meanwhile, glycerol 3-phosphate is connected with the galactoglyceride biosynthetic pathway by glycerol 3-phosphate dehydrogenase (G3PD), monogalactosyl diacylglyceride synthase (MGDGS), and digalactosyl diacylglyceride synthase (DGDGS). The results of our study confirm that low GALT transcripts are correlated with thalli softness to locate reproductive structures, as well as constricting the synthesis of UDP-hexoses for galactan backbone synthesis in the presence of two volatile regulators and methionine. Meanwhile, α-galactosidase modulates expression according to cystocarp maturation, and we found high transcripts in late development stages, as occurred in the presence of methyljasmonate, compared to early stages in ethylene. Regarding the acylglyceride pool, the upregulation of G3PD, MGDGS, and DGDGS gene expression in G. imbricata treated with MEJA supports lipid remodeling, as high levels of transcripts for MGDGS and DGDGS provide membrane stability during late development stages of cystocarps. Similar behavior is assumed in three naturally collected thalli development stages-namely, fertile, fertilized, and fertile-under 65 psu salinity conditions. Low transcripts for α-galactosidase and high for G3PD are reported in infertile and fertilized thalli, which is the opposite to high transcripts for α-galactosidase and low for G3PD encountered in fertile thalli within visible cystocarps compared to each of their corresponding stages in 35 psu. No significant changes are reported for MGDGS and DGDGS. It is concluded that cystocarp and thallus development stages affect galactose and glycerides pools with interwoven effects on cell wall polysaccharides.


Assuntos
Ciclopentanos , Glicerol/análogos & derivados , Glicerofosfatos , Oxilipinas , Rodófitas , Alga Marinha , Galactose , alfa-Galactosidase , Galactanos , Glucose , Difosfato de Uridina
10.
Mar Drugs ; 22(3)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38535453

RESUMO

Brown seaweeds are attracting attention due to their richness in bioactive compounds, in particular, their phlorotannins. We present here a case study of two Fucales, Ascophyllum nodosum and Halidrys siliquosa, sustainably collected, to produce active polyphenols for the cosmetics sector. Phenolic contents of crude extracts, obtained by Accelerated Solvent Extraction (ASE), were more elevated in H. siliquosa at 100.05 mg/g dry weight (DW) than in A. nodosum (29.51 mg/g DW), considering 3 cycles with cell inversion. The temperature of extraction for a high phenolic content and high associated antioxidant activities close to positive controls was 150 °C for both algae and the use of only one cycle was enough. A semi-purification process using Solid-phase Extraction (SPE) was carried out on both ASE crude extracts (one per species). The majority of phlorotannins were found in the ethanolic SPE fraction for A. nodosum and the hydroethanolic one for H. siliquosa. The SPE process allowed us to obtain more concentrated fractions of active phenolic compounds (×1.8 and 2 in A. nodosum and H. siliquosa, respectively). Results are discussed in regard to the exploitation of seaweeds in Brittany and to the research of sustainable processes to produce active natural ingredients for cosmetics.


Assuntos
Cosméticos , Alga Marinha , Antioxidantes , Etanol , Fenóis , Misturas Complexas
11.
Mar Drugs ; 22(3)2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38535462

RESUMO

The effect of UV radiation on the accumulation of mycosporine-like amino acids (MAAs) and pigments was investigated on red macroalga Palmaria palmata cultivated for 21 days. The data were combined with the effect of NaNO3 to further investigate the synthesis of these nitrogenous compounds. A progressive decrease in both total MAA and pigment contents was observed, with a positive effect of nitrate supply. Usujirene was the only MAA exhibiting a significantly increasing content when exposed to UV radiation, changing from 9% to 24% of the total MAA's contribution, with no variation observed with NaNO3. This suggests a specific induction or synthesis pathway of usujirene for photoprotection, while the synthesis of other MAAs could have been limited by an insufficient amount of UV radiation and/or irradiance. The photoprotective ability of some MAAs could have been impacted by nitrogen starvation over time, resulting in a limited synthesis and/or potential use of MAAs as a nitrogen source for red macroalgae. The data confirmed the multiple effects of environmental factors on the synthesis of MAAs while providing new insights into the specific synthesis of usujirene, which could find an application in the cosmetics sector as natural sunscreen or an anti-ageing agent.


Assuntos
60578 , Rodófitas , Alga Marinha , Aminoácidos , Nitrogênio
12.
PLoS One ; 19(3): e0295740, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38536857

RESUMO

Microbial inoculants can increase the yield of cultivated crops and are successful in independent trials; however, efficacy drops in large-scale applications due to insufficient consideration of microbial community dynamics. The structure of microbiomes, in addition to the impact of individual taxa, is an important factor to consider when designing growth-promoting inoculants. Here, we investigate the microbial network and community assembly patterns of Macrocystis pyrifera gametophyte germplasm cultures (collectively referred to as a "seedbank") used to cultivate an offshore farm in Santa Barbara, California, and identify network features associated with increased biomass of mature sporophytes. We found that [1] several network features, such as clustering coefficient and edge ratios, significantly vary with biomass outcomes; [2] gametophytes that become low- or high-biomass sporophytes have different hub taxa; and [3] microbial community assembly of gametophyte germplasm cultures is niche-driven. Overall, this study describes microbial community dynamics in M. pyrifera germplasm cultures and ultimately supports the development of early life stage inoculants that can be used on seaweed cultivars to increase biomass yield.


Assuntos
Kelp , Macrocystis , Alga Marinha , Fazendas , Biomassa , Consórcios Microbianos
13.
Int J Mol Sci ; 25(6)2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38542473

RESUMO

The conversion of lignocellulosic and algal biomass by thermophilic bacteria has been an area of active investigation. Thermoanaerobacter species have proven to be particularly capable in the production of bioethanol and biohydrogen from lignocellulosic biomass, although detailed studies of their abilities to utilize the full gamut of carbohydrate, amino acids, and proteins encountered in biomass hydrolysates are seldom comprehensively examined. Here, we re-evaluate the ability of Thermoanaerobacter strain AK15, a highly ethanologenic strain previously isolated from a hot spring in Iceland. Similar to other Thermoanaerobacter species, the strain degraded a wide range of mono- and di-saccharides and produced a maximum of 1.57 mol ethanol per mol of glucose degraded at high liquid-gas phase ratios. The ability of strain AK15 to utilize amino acids in the presence of thiosulfate is limited to the branched-chain amino acids as well as serine and threonine. Similar to other Thermoanaerobacter species, strain AK15 produces a mixture of branched-chain fatty acids and alcohols, making the strain of interest as a potential source of longer-chain alcohols. Finally, the strain was also shown to use butyrate as an electron sink during glucose degradation resulting in the reduced product butanol, in addition to end-products produced from glucose. Thus, strain AK15 is a promising candidate for ethanol and higher-order alcohols from a range of lignocellulosic and algal biomass.


Assuntos
Aminoácidos , Alga Marinha , Aminoácidos/metabolismo , Alga Marinha/metabolismo , Etanol/metabolismo , Aminoácidos de Cadeia Ramificada/metabolismo , Glucose/metabolismo , Fermentação
14.
Carbohydr Polym ; 334: 122038, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38553205

RESUMO

The widespread use of disposable plastic straws has caused a long-lasting environmental problem. Potential alternatives for plastic straws are far from satisfactory due to the low utility, poor water stability, and non-ideal natural degradability. In this work, an edible, hydrostable, and degradable straw was developed from the economically significant seaweed. Seaweed-derived insoluble cellulose fibers were used as the building block of the straw, and the soluble polysaccharide extracts were explored as the natural glue through the chelation with Ca2+. Repeated freeze-thawing was introduced to strengthen the molecular interactions, which further improved its mechanical stability and hydrostability. The straw exhibited remarkable natural degradability in open environments, particularly in marine-mimicking conditions. By incorporating pH-sensitive food pigments, the straws could indicate acid-base property of a beverage or even discriminate the freshness of milk. The versatile seaweed-derived straw adhered to the biocycle concept of "from sea to sea" to alleviate the burden of white pollution on oceans.


Assuntos
Celulose , Alga Marinha , Polissacarídeos
15.
Bioresour Technol ; 399: 130631, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38554760

RESUMO

Macroalgae biomass has been considered as a promising renewable feedstock for lactic acid production owing to its lignin-free, high carbohydrate content and high productivity. Herein, the D-lactic acid production from red macroalgae Gelidium amansii by Pediococcus acidilactici was investigated. The fermentable sugars in G. amansii acid-prehydrolysate were mainly galactose and glucose with a small amounts of xylose. P. acidilactici could simultaneously ferment the mixed sugars of galactose, glucose and xylose into D-lactic acid at high yield (0.90 g/g), without carbon catabolite repression (CCR). The assimilating pathways of these sugars in P. acidilactici were proposed based on the whole genome sequences. Simultaneous saccharification and co-fermentation (SSCF) of the pretreated and biodetoxified G. amansii was also conducted, a record high of D-lactic acid (41.4 g/L) from macroalgae biomass with the yield of 0.34 g/g dry feedstock was achieved. This study provided an important biorefinery strain for D-lactic acid production from macroalgae biomass.


Assuntos
60578 , Ácido Láctico , Rodófitas , Alga Marinha , Fermentação , Xilose/metabolismo , Galactose/metabolismo , Alga Marinha/metabolismo , Glucose/metabolismo
16.
J Med Food ; 27(4): 359-368, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38526569

RESUMO

As the body's largest organ, the skin is located at the internal and external environment interface, serving as a line of defense against various harmful stressors. Recently, marine-derived physiologically active ingredients have attracted considerable attention in the cosmeceutical industry due to their beneficial effects on skin health. Sargassum, a genus of brown macroalgae, has traditionally been consumed as food and medicine in several countries and is rich in bioactive compounds such as meroterpenoids, sulfated polysaccharides, fucoidan, fucoxanthin, flavonoids, and terpenoids. Sargassum spp. have various beneficial effects on skin disorders. They help with atopic dermatitis by improving skin barrier protection and reducing inflammation. Several species show potential in treating acne by inhibiting bacterial growth and reducing inflammation. Some species, such as Sargassum horneri, demonstrate antiallergic effects by modulating mast cell activity. Certain Sargassum species exhibit anticancer activity by inhibiting tumor growth and promoting apoptosis, and some species help with wound healing by promoting angiogenesis and reducing oxidative stress. Overall, Sargassum spp. demonstrate potential for treating and managing various skin conditions. Therefore, the bioactive compounds of Sargassum spp. may be natural ingredients with a wide range of functional properties for preventing and treating skin disorders. The present review focused on the various biological effects of Sargassum extracts and derived compounds on skin disorders.


Assuntos
Sargassum , Alga Marinha , Humanos , Pele , Inflamação , Terpenos/farmacologia
17.
Environ Pollut ; 348: 123801, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38527581

RESUMO

Microplastics and other microscopic debris are a concern in the coastal environment but measurements in the water column and sediment are often problematic and rely on non-standardised and highly variable methodologies. To this end, we explore the potential of different species of temperate-cold marine macroalgae as passive biomonitors of anthropogenic microparticles at three contrasting locations in southwest England. Specifically, fronds from samples of fucoids and Ulva lactuca (n = 9 in total, and three from each location) have been sectioned and analysed directly under a microscope and anthropogenic microparticles counted and subsequently characterised for chemical composition. Microparticles were heterogeneously distributed throughout sections from the same sample. However, on a dry weight basis, combined microparticle concentrations for each sample ranged from about 7.5 g-1 to 110 g-1, and from about 0.2 cm-2 to 0.9 cm-2, and for a given species were higher in samples from a semi-enclosed harbour and urban beach than in samples from a protected beach facing the open sea. These values compare with published concentrations of microplastics and microfibres reported for the regional water column on the order of 0.1 m-3. Most particles were cellulosic (e.g., rayon) and petroleum-based (mainly polyester and polyethylene terephthalate) fibres but plastic fragments were also present on most samples. Glass retroreflective beads derived from road markings were also present at up to 18 g-1 on fucoids from the urban beach because of its proximity to a stormwater effluent. Most microparticles were adhered to the smooth parts of the macroalgal surface but some displayed wrapping around edges and creases or entrapment by appendages. The practical and environmental implications of macroalgae passively capturing significant quantities of anthropogenic microparticles are discussed.


Assuntos
60578 , Alga Marinha , Ulva , Poluentes Químicos da Água , Microplásticos/análise , Plásticos/análise , Monitoramento Biológico , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Água/análise
18.
Eur Thyroid J ; 13(2)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38471306

RESUMO

Global warming is now universally acknowledged as being responsible for dramatic climate changes with rising sea levels, unprecedented temperatures, resulting fires and threatened widespread species loss. While these effects are extremely damaging, threatening the future of life on our planet, one unexpected and paradoxically beneficial consequence could be a significant contribution to global iodine supply. Climate change and associated global warming are not the primary causes of increased iodine supply, which results from the reaction of ozone (O3) arising from both natural and anthropogenic pollution sources with iodide (I-) present in the oceans and in seaweeds (macro- and microalgae) in coastal waters, producing gaseous iodine (I2). The reaction serves as negative feedback, serving a dual purpose, both diminishing ozone pollution in the lower atmosphere and thereby increasing I2. The potential of this I2 to significantly contribute to human iodine intake is examined in the context of I2 released in a seaweed-abundant coastal area. The bioavailability of the generated I2 offers a long-term possibility of increasing global iodine status and thereby promoting thyroidal health. It is hoped that highlighting possible changes in iodine bioavailability might encourage the health community to address this issue.


Assuntos
Iodo , Ozônio , Alga Marinha , Humanos , Mudança Climática , Oceanos e Mares , Ozônio/análise , Atmosfera
19.
Mar Pollut Bull ; 201: 116259, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38492267

RESUMO

Early detection of invasive species is crucial to deal effectively with biological invasions in ports, which are hotspots of species introductions. In this study, a simplified end-time PCR methodology conducted on eDNA from water samples was developed for rapid detection of the invasive seaweed Asparagopsis armata (four hours from water collection to result visualization). It was tested dockside in four international Spanish ports in presence of stakeholders, whose feedback was obtained to explore the real applicability of this biotechnology. Although biological invasions were not a main concern for them, results indicate a unanimous approval of the methodology by the stakeholders, having detected the presence of A. armata in three of the ports. Stakeholders suggested further developments for easier application of the tool and multiple species detection, to be adopted for the control of invasive species in ports.


Assuntos
Rodófitas , Alga Marinha , Alga Marinha/genética , Rodófitas/genética , Espécies Introduzidas , Água
20.
J Environ Manage ; 356: 120526, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38492423

RESUMO

The equilibrium of the marine ecosystem is currently threatened by several constraints, among which climate change and anthropogenic activities stand out. Indeed, these factors favour the growth of macroalgae, which sometimes end up stranded on the beaches at the end of their life cycle, forming what is known as beach wrack. Despite its undeniable important ecological role on beaches, as it is an important source of organic matter (OM), and provides food and habitat for several invertebrates, reptiles, small mammals, and shorebirds, the overaccumulation of beach wrack is often associated with the release of greenhouse gases, negatively impacting tourist activities, and generating economic expenses for its removal. Although currently beach wrack is mainly treated as a waste, it can be used for numerous potential applications in distinct areas. This review aimed at providing a solid point of view regarding the process of wrack formation, its spatiotemporal location, as well as its importance and risks. It also contains the current advances of the research regarding sustainable alternatives to valorise this organic biomass, that range from bioenergy production to the incorporation of wrack in agricultural soils, considering a circular economy concept. Although there are some concerns regarding wrack utilisation, from its variable availability to a possible soil contamination with salts and other contaminants, this review comprises the overall beneficial effects of the incorporation of this residue particularly in the organic agricultural model, strengthening the conversion of this wasted biomass into a valuable resource.


Assuntos
Ecossistema , Alga Marinha , Animais , Agricultura , Biomassa , Solo/química , Mamíferos
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