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1.
Microbes Environ ; 37(2)2022.
Artigo em Inglês | MEDLINE | ID: mdl-35691910

RESUMO

Persistent RNA viruses, which have been suggested to form symbiotic relationships with their hosts, have been reported to occur in eukaryotes, such as plants, fungi, and algae. Based on empirical findings, these viruses may also be present in commercially cultivated macroalgae. Accordingly, the present study aimed to screen red macroalgae (family Bangiaceae conchocelis and Neopyropia yezoensis thallus) and processed nori sheets (N. yezoensis) for persistent RNA viruses using fragmented and primer-ligated dsRNA sequencing (FLDS) and targeted reverse transcription PCR (RT-PCR). A Totiviridae-related virus was detected in the conchocelis of Neoporphyra haitanensis, which is widely cultivated in China, while two Mitoviridae-related viruses were found in several conchocelis samples and all N. yezoensis-derived samples (thallus and nori sheets). Mitoviridae-related viruses in N. yezoensis are widespread among cultivated species and not expected to inhibit host growth. Mitoviridae-related viruses were also detected in several phylogenetically distant species in the family Bangiaceae, which suggests that these viruses persisted and coexist in the family Bangiaceae over a long period of time. The present study is the first to report persistent RNA viruses in nori sheets and their raw materials.


Assuntos
Porphyra , Vírus de RNA , Alga Marinha , Eucariotos/genética , Plantas/genética , Porphyra/genética , Vírus de RNA/genética , RNA de Cadeia Dupla
2.
Mar Environ Res ; 178: 105662, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35642998

RESUMO

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.


Assuntos
Rodófitas , Alga Marinha , Animais , Aves , Carboidratos , Clorofila A , Aquecimento Global , Oceanos e Mares , Salinidade , Temperatura
3.
Food Res Int ; 156: 111156, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35651022

RESUMO

Until now, although different studies have shown the potential prebiotic effect of seaweed carbohydrates, no studies with the whole seaweeds have been carried out. In addition, the prebiotic effect throughput sequencing remains poorly investigated since most of the published works used qPCR or FISH to estimate bacterial changes. In this work, an in vitro model of the human distal colon was used to determine, for the first time, the potential prebiotic effect of a brown whole seaweed Himanthalia elongata. The whole seaweed was characterized in basis of its nutritional and mineral composition and submitted to the entire gastrointestinal digestion. The prebiotic effect was evaluated by the microbial modulation through 16S rRNA amplicon sequencing, qPCR and short-chain fatty acid analysis. The obtained results indicated that the colonic fraction of H. elongata was used selectively by the Bacteroides genus, more specifically by the specie Bacteoides ovatus, whereas inulin was used mainly by the Parabacteroides genus, being Parabacteroides distasonis the most abundant identified specie. Selective use of inulin by P. distasonis is, therefore, reported by the first time. qPCR analysis shown no significative differences in Bifidobacterium population and a decrease in Lactobacillus along the fermentation assays with both substrates. Regarding to the short-fatty acid production, maximal concentration, 56.11 ± 20.48 mM, was achieved for H. elongata, at 24 h of fermentation whereas for inulin total acid production was 93.66 ± 21.82 mM at 48 h of assay. The metabolic pathways associated with bacterial genera were not significantly different between the two tested substrates. Although more studies are necessary to elucidate the prebiotic character of H. elongata, the results presented in this work are promissory and could open new opportunities of research and application in the area of Nutrition and Food Chemistry.


Assuntos
Besouros , Feófitas , Alga Marinha , Animais , Colo/microbiologia , Humanos , Inulina , Feófitas/química , Prebióticos , RNA Ribossômico 16S/genética , Verduras
4.
Proc Natl Acad Sci U S A ; 119(23): e2121705119, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35653565

RESUMO

SignificanceMarine conservation and the establishment of marine protected areas (MPAs) have gained attention as ways to protect and restore ecosystems and rebuild fish populations. They may also play an important role in sequestering carbon and reducing emissions from sources such as habitat degradation. Implementing six strategies for enhancing blue carbon sinks, including establishing MPAs to protect and restore coastal wetlands, macroalgae forests, and seafloor sediments and expand seaweed farming can not only remove significant amounts of carbon and avoid emissions but also bring many more environmental and human-related benefits.


Assuntos
Sequestro de Carbono , Carbono , Conservação dos Recursos Naturais , Alga Marinha , Animais , Aquicultura , Clima , Ecossistema , Peixes , Áreas Alagadas
5.
PLoS One ; 17(6): e0269067, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35653349

RESUMO

The effect of fertilization on the yield of medicinal and aromatic plants is important. Among various fertilizers, seaweed is an environment friendly organic fertilizer. This study was conducted to determine the effects of foliar application of different doses of seaweed extract on the yield and essential oil content of coriander. Application was done before and at the beginning of flowering at two different locations. Results showed that the essential oil content was higher in the location with high sand content while the yield and yield components were higher at the location with low sand content and high organic matter content. Seaweed application at a dose of 2 ml L-1 showed positive effects on the growth, development, yield and essential oil contents of coriander plant. Linalool (%) was determined as the most important essential oil compound and the foliar application of seaweed showed positive effects on the linalool percentage. It can be stated that the foliar application of seaweed (organic fertilizers) has beneficial impacts in terms of increasing the yield and quality traits of coriander.


Assuntos
Coriandrum , Óleos Voláteis , Alga Marinha , Coriandrum/química , Fertilizantes , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Areia , Verduras
6.
Ying Yong Sheng Tai Xue Bao ; 33(5): 1420-1428, 2022 May.
Artigo em Chinês | MEDLINE | ID: mdl-35730102

RESUMO

Green tide in the sea is an abnormal ecological phenomenon caused by the explosive proliferation or high aggregation of some green macroalgae under particular environmental conditions. Since 2007, green tides have occurred in the Yellow Sea for 15 consecutive years, resulting in extremely serious damage to coastal ecological environment, social development, and economic construction. Therefore, it is urgent to solve the green tide problem, which is driven by external and internal factors. Global researchers have scientifically recognized the external causes (environmental factors) of the green tide blooms, and have carried out a series of studies on the physiological response of green tide algae to some environmental factors and obtained some achievements. However, the internal causes of green tide blooms, which is the intense ecophysiological adaptability of green tide algae in response to drastic fluctuation of environmental factors, has not yet been sufficiently addressed. From the perspective of algae ecophysiology, we reviewed the response mechanisms of green tide forming species to the fluctuations of various ecological factors, including light intensity, carbon dioxide, temperature, salinity, desiccation, nutrient, heavy metals, and biotic factors. Moreover, we summarized the adaptive regulation mechanisms of green tide algae dealing with fluctuating environmental factors from the aspects of photosynthetic and growth physiology, nutritional physio-logy, and reproductive physiology, which help reveal the internal mechanisms of green tide blooming.


Assuntos
Clorófitas , Alga Marinha , Ulva , China , Eutrofização , Fotossíntese , Alga Marinha/fisiologia , Temperatura
7.
Front Biosci (Elite Ed) ; 14(2): 13, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35730454

RESUMO

Aqueous extracts of two red seaweeds Halymenia porphyriformis and Solieria robusta were used to synthesize green silver nanoparticles. These biogenic nanoparticles were tested against four strains of oral pathogenic bacteria which cause tooth decay or cavities. Staphylococcus aureus (MT416445), Streptococcus viridans (MT416448), Lactobacillus acidophilus (MT416447) and Lactobacillus brevis (MT416446) were used. Characterization of AgNPs was done by UV-Visible spectroscopy, SEM, XRD and FTIR. XRD analysis revealed the crystalline nature of the particles. The size analysis by XRD of the green AgNPs by H. porphyriformis indicated it had smaller particles, 15.23 nm, when compared to AgNPs by S. robusta (17 nm). Both green synthesized silver nanoparticles showed moderate antibacterial activity against all strains of bacteria, except L. acidophilus. Both particles showed their maximum zone of inhibition against L. acidophilus at a lower concentration of 50 and 100 µg. However, it was concluded that silver nanoparticles of H. porphyriformis are more effective than that of S. robusta due to their smaller size.


Assuntos
Nanopartículas Metálicas , Alga Marinha , Bactérias , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Prata/química , Prata/farmacologia
8.
Sci Total Environ ; 839: 156230, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35643144

RESUMO

Marine eutrophication is a pervasive and growing threat to global sustainability. Macroalgal cultivation is a promising circular economy solution to achieve nutrient reduction and food security. However, the location of production hotspots is not well known. In this paper the production potential of macroalgae of high commercial value was predicted across the Baltic Sea region. In addition, the nutrient limitation within and adjacent to macroalgal farms was investigated to suggest optimal site-specific configuration of farms. The production potential of Saccharina latissima was largely driven by salinity and the highest production yields are expected in the westernmost Baltic Sea areas where salinity is >23. The direct and interactive effects of light availability, temperature, salinity and nutrient concentrations regulated the predicted changes in the production of Ulva intestinalis and Fucus vesiculosus. The western and southern Baltic Sea exhibited the highest farming potential for these species, with promising areas also in the eastern Baltic Sea. Macroalgal farming did not induce significant nutrient limitation. The expected spatial propagation of nutrient limitation caused by macroalgal farming was less than 100-250 m. Higher propagation distances were found in areas of low nutrient and low water exchange (e.g. offshore areas in the Baltic Proper) and smaller distances in areas of high nutrient and high water exchange (e.g. western Baltic Sea and Gulf of Riga). The generated maps provide the most sought-after input to support blue growth initiatives that foster the sustainable development of macroalgal cultivation and reduction of in situ nutrient loads in the Baltic Sea.


Assuntos
Fucus , Alga Marinha , Países Bálticos , Eutrofização , Nutrientes , Oceanos e Mares , Água
9.
Environ Pollut ; 307: 119560, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35654256

RESUMO

As a precursor to risk assessment and risk management through consuming contaminated seafood, food safety needs to be quantified and assured. Seaweed is an increasing dietary component, especially in developing countries, but there are few studies assessing uptake rates of contaminants from this route. As such, the present study determined likely human uptake due to the trace elemental (Fe, Mn, Ni, Cu, Zn, Se, Hg, and As) concentrations in the edible red seaweeds (Rhodophyta) Gelidium pusillum and Hypnea musciformis, growing in the industrialised Cox's Bazar coastal area of Bangladesh. Metal and metalloid concentrations in G. pusillum were in the order (mg/kg): Fe (797 ± 67) > Mn (69 ± 4) > Ni (12 ± 5) > Zn (9 ± 4) > Cu (9 ± 4) >Se (0.1 ± 0.1) > Hg (0.1 ± 0.01), and in H. musciformis: Fe (668 ± 58) > Mn (28 ± 5) > Ni (14 ± 2) > Zn (11 ± 5) > Cu (6 ± 4) >Se (0.2 ± 0.03) > Hg (0.04 ± 0.01). Despite the industrial activities in the area, and based on 10 g. day-1 seaweed consumption, it is concluded that these concentrations pose no risk to human health as part of a normal diet according to the targeted hazard quotient and hazard index (THQ and HI) (values < 1). In addition, and as a novel aspect for seaweeds, Selenium Health Benefit Values (Se-HBV) were determined and found to have positive values. Seaweed can be used as an absorber of inorganic metals for removing contamination in coastal waters. The results are a precursor to further research regarding the efficiency and rate at which seaweeds can sequester metal contamination in water. In addition, management techniques need to be developed thereby to control the contaminant inputs.


Assuntos
Mercúrio , Metais Pesados , Rodófitas , Alga Marinha , Oligoelementos , Poluentes Químicos da Água , Bioacumulação , Monitoramento Ambiental/métodos , Humanos , Metais Pesados/análise , Medição de Risco , Oligoelementos/análise , Poluentes Químicos da Água/análise
10.
Mar Drugs ; 20(5)2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35621930

RESUMO

Fucoxanthin, belonging to the xanthophyll class of carotenoids, is a natural antioxidant pigment of marine algae, including brown macroalgae and diatoms. It represents 10% of the total carotenoids in nature. The plethora of scientific evidence supports the potential benefits of nutraceutical and pharmaceutical uses of fucoxanthin for boosting human health and disease management. Due to its unique chemical structure and action as a single compound with multi-targets of health effects, it has attracted mounting attention from the scientific community, resulting in an escalated number of scientific publications from January 2017 to February 2022. Fucoxanthin has remained the most popular option for anti-cancer and anti-tumor activity, followed by protection against inflammatory, oxidative stress-related, nervous system, obesity, hepatic, diabetic, kidney, cardiac, skin, respiratory and microbial diseases, in a variety of model systems. Despite much pharmacological evidence from in vitro and in vivo findings, fucoxanthin in clinical research is still not satisfactory, because only one clinical study on obesity management was reported in the last five years. Additionally, pharmacokinetics, safety, toxicity, functional stability, and clinical perspective of fucoxanthin are substantially addressed. Nevertheless, fucoxanthin and its derivatives are shown to be safe, non-toxic, and readily available upon administration. This review will provide pharmacological insights into fucoxanthin, underlying the diverse molecular mechanisms of health benefits. However, it requires more activity-oriented translational research in humans before it can be used as a multi-target drug.


Assuntos
Neoplasias , Alga Marinha , Carotenoides , Humanos , Alga Marinha/química , Xantofilas/química , Xantofilas/farmacologia , Xantofilas/uso terapêutico
11.
Mar Drugs ; 20(5)2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35621939

RESUMO

2-keto-3-deoxy sugar acids, which have potential as precursors in medicinal compound production, have gained attention in various fields. Among these acids, 2-keto-3-deoxy-l-galactonate (KDGal) has been biologically produced from D-galacturonate originating from plant-derived pectin. KDGal is also found in the catabolic pathway of 3,6-anhydro-l-galactose (AHG), the main component of red-algae-derived agarose. AHG is converted to 3,6-anhydrogalactonate by AHG dehydrogenase and subsequently isomerized to KDGal by 3,6-anhydrogalactonate cycloisomerase. Therefore, we used the above-described pathway to produce KDGal from agarose. Agarose was depolymerized to AHG and to agarotriose (AgaDP3) and agaropentaose (AgaDP5), both of which have significantly higher molecular weights than AHG. When only AHG was converted to KDGal, AgaDP3 and AgaDP5 remained unreacted. Finally, KDGal was effectively purified from the enzymatic products by size-exclusion chromatography based on the differences in molecular weights. These results show that KDGal can be enzymatically produced and purified from agarose for use as a precursor to high-value products.


Assuntos
Rodófitas , Alga Marinha , Galactose/química , Pectinas , Rodófitas/química , Alga Marinha/química , Sefarose/química
12.
Mar Drugs ; 20(5)2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35621947

RESUMO

Crude polysaccharides, extracted from two seaweed species (Hizikia fusiforme and Sargassum horneri) and Haliotis discus hannai (abalone) viscera, were evaluated for their inhibitory effect against SARS-CoV-2 propagation. Plaque titration revealed that these crude polysaccharides efficiently inhibited SARS-CoV-2 propagation with IC50 values ranging from 0.35 to 4.37 µg/mL. The crude polysaccharide of H. fusiforme showed the strongest antiviral effect, with IC50 of 0.35 µg/mL, followed by S. horneri and abalone viscera with IC50 of 0.56 and 4.37 µg/mL, respectively. In addition, immunofluorescence assay, western blot, and quantitative RT-PCR analysis verified that these polysaccharides could inhibit SARS-CoV-2 replication. In Vero E6 cells, treatment with these crude polysaccharides before or after viral infection strongly inhibited the expression level of SARS-CoV-2 spikes, nucleocapsid proteins, and RNA copies of RNA-dependent RNA-polymerase and nucleocapsid. These results show that these crude marine polysaccharides effectively inhibit SARS-CoV-2 propagation by interference with viral entry.


Assuntos
COVID-19 , Alga Marinha , Antivirais/farmacologia , COVID-19/tratamento farmacológico , Humanos , Polissacarídeos/farmacologia , RNA , SARS-CoV-2 , Vísceras
13.
Biosensors (Basel) ; 12(5)2022 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-35624660

RESUMO

Kelp and laver are large economic macroalgae in China, which are rich in nutrients, especially Mn and Zn. Excessive intake of Mn and Zn can be harmful to the human body. Therefore, it is necessary to develop a convenient and efficient method to detect the contents of Mn and Zn in macroalgae. In this experiment, red carbon dots (R-CDs) doped with N and S elements were prepared by the thermal solvent method. The obtained R-CDs displayed excitation wavelength-independent fluorescent emission in the red spectral region. The R-CDs were used to construct a fluorescent probe for specific recognition of Mn2+ and Zn2+, achieving high-sensitivity detection of Mn2+ and Zn2+. The detection results showed a good linear relationship between fluorescence intensity and Mn2+ concentration, and the calculated detection limit was 0.23 nmol/L. For the detection of Zn2+, the detection limit was estimated as 19.1 nmol/L. At the same time, the content distribution of Mn and Zn elements in macroalgae produced in Fujian was investigated by the constructed fluorescence probe. It was found that kelp, laver, and their products are rich in Mn and Zn elements, and the content of Mn and Zn elements in laver is higher than that in kelp, which can be used as the optimal food supplement for Mn and Zn elements.


Assuntos
Pontos Quânticos , Alga Marinha , Carbono , Corantes Fluorescentes , Humanos , Íons , Zinco
14.
Nutrients ; 14(10)2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35631304

RESUMO

Diet is known to affect the composition and metabolite production of the human gut microbial community, which in turn is linked with the health and immune status of the host. Whole seaweeds (WH) and their extracts contain prebiotic components such as polysaccharides (PS) and polyphenols (PP). In this study, the Australian seaweeds, Phyllospora comosa, Ecklonia&nbsp;radiata,&nbsp;Ulva ohnoi, and their PS and PP extracts were assessed for potential prebiotic activities using an in vitro gut model that included fresh human faecal inoculum. 16S rRNA sequencing post gut simulation treatment revealed that the abundance of several taxa of commensal bacteria within the phylum Firmicutes linked with short chain fatty acid (SCFA) production, and gut and immune function, including the lactic acid producing order Lactobacillales and the chief butyrate-producing genera Faecalibacteria, Roseburia, Blautia, and Butyricicoccus were significantly enhanced by the inclusion of WH, PS and PP extracts. After 24 h fermentation, the abundance of total Firmicutes ranged from 57.35-81.55% in the WH, PS and PP samples, which was significantly greater (p ≤ 0.01) than the inulin (INU) polysaccharide control (32.50%) and the epigallocatechingallate (EGCG) polyphenol control (67.13%); with the exception of P. comosa PP (57.35%), which was significantly greater than INU only. However, all WH, PS and PP samples also increased the abundance of the phylum Proteobacteria; while the abundance of the phylum Actinobacteria was decreased by WH and PS samples. After 24 h incubation, the total and individual SCFAs present, including butyric, acetic and propionic acids produced by bacteria fermented with E. radiata and U. ohnoi, were significantly greater than the SCFAs identified in the INU and EGCG controls. Most notably, total SCFAs in the E. radiata PS and U. ohnoi WH samples were 227.53 and 208.68 µmol/mL, respectively, compared to only 71.05 µmol/mL in INU and 7.76 µmol/mL in the EGCG samples. This study demonstrates that whole seaweeds and their extracts have potential as functional food ingredients to support normal gut and immune function.


Assuntos
Microbioma Gastrointestinal , Alga Marinha , Austrália , Bactérias , Clostridiales/genética , Carboidratos da Dieta/metabolismo , Ácidos Graxos Voláteis/metabolismo , Humanos , Inulina/farmacologia , Extratos Vegetais/farmacologia , Polissacarídeos/farmacologia , Prebióticos , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo
15.
Int J Biol Macromol ; 211: 499-505, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35561860

RESUMO

This study is aimed at identifying and characterising the proteases we previously extracted from the red seaweed Gracilaria edulis with the potential as milk-clotting enzymes. The protease extract was first analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and zymography. Two protease bands with a molecular weight of 44 and 108 kDa were identified, and analysed using in-gel digestion and liquid chromatography-tandem mass spectrometry/mass spectrometry (LC-MS/MS). Eight peptides from the LC-MS/MS analysis matched those in existing protein databases but they were not related to any protease of the genera Gracilaria and Hydropuntia. Further analysis revealed that more than 80% of the peptide sequence of the algal proteases matched with those from members of the bacteria kingdom, including Gallaecimonas and Alteromonas. Among these, twelve matching homolog proteases were identified as metalloprotease and serine protease. The results indicated that the algal proteases have a close relationship with both algae and bacteria, and suggest that the proteases might have resulted from past bacterial colonisation of the algae and subsequent horizontal gene transfer between bacteria and algae.


Assuntos
Gracilaria , Alga Marinha , Sequência de Aminoácidos , Animais , Cromatografia Líquida , Eletroforese em Gel de Poliacrilamida , Gracilaria/química , Leite/química , Alga Marinha/química , Serina Proteases/química , Serina Proteases/genética , Espectrometria de Massas em Tandem
16.
Int J Biol Macromol ; 211: 524-534, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35577199

RESUMO

Sulfated polysaccharides (SPs) from seaweeds are potential bioactive natural compounds, but their DNA protective activity is poorly explored. This article aimed to evaluate the genotoxic/antigenotoxic potentials of a sulfated heterofucan from brown seaweed Spatoglossum schröederi (Fucan A - FA) and a sulfated galactan from green seaweed Codium isthomocladum (3G4S) using in vitro Comet assay (alkaline and oxidative versions) with HepG2 cells. The antioxidant activity of these SPs was evaluated by total antioxidant capacity, radical scavenging, metal chelating, and antioxidant enzyme activity assays. Both SPs were not genotoxic. FA and 3G4S displayed strong antigenotoxic activity against oxidizing chemical (H2O2) but not against alkylating chemical (MMS). The DNA damage reduction after a pre-treatment of 72 h with these SPs was 81.42% to FA and 81.38% to 3G4S. In simultaneous exposure to FA or 3G4S with H2O2, HepG2 cells presented 48.04% and 55.41% of DNA damage reduction compared with the control, respectively. The antigenotoxicity of these SPs relates to direct antioxidant activity by blockage of the initiation step of the oxidative chain reaction. Therefore, we conclude that FA and 3G4S could be explored as functional natural compounds with antigenotoxic activity due to their great protection against oxidative DNA damage.


Assuntos
Alga Marinha , Sulfatos , Antioxidantes/química , Antioxidantes/farmacologia , Dano ao DNA , Peróxido de Hidrogênio , Oxirredução , Polissacarídeos/química , Polissacarídeos/farmacologia , Alga Marinha/química , Sulfatos/química
17.
Fish Shellfish Immunol ; 126: 164-177, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35623544

RESUMO

This study evaluated the effects of agar waste (AW) dietary supplementation, obtained from the seaweed Gracilaria gracilis cultivated under two different spectral lights, neutral (NT) and blue (BL), on haematological parameters, inflammatory response, and antioxidant biomarkers of gilthead seabream (Sparus aurata). Three diets were prepared: i) a basal diet (CTR), ii) a diet supplemented with 2.5% NT, and iii) a diet supplemented with 2.5% BL. After 15 days of feeding, fish were injected with PBS (placebo) or inactivated Photobacterium damselae subsp. piscicida (stimulated) and sampled at 4 h and 24 h post-stimulus. Results indicated that fish fed NT and BL supplemented diets had lower Ht value and mean corpuscular volume (MCV) than fish fed the CTR diet, regardless of the stimulus and the sampling time. No differences in mean corpuscular haemoglobin (MCH) were found between fish fed the different diets, while the mean corpuscular haemoglobin concentration (MCHC) increased in fish fed AW supplemented diets compared to fish fed the CTR diet, regardless of the stimulus and the sampling time. In response to inflammation, fish fed the NT diet displayed higher neutrophils count in blood when compared to the CTR group, regardless of the stimulus and sampling time. Thrombocyte count was higher in fish fed NT and BL diets than in the CTR group, especially in the stimulated fish (Diet*injection (D*I), P = 0.004). An increase in plasma protease activity was detected in fish fed NT or BL diets in both placebo and stimulated fish regardless of the sampling time. Hepatic catalase activity was higher in fish fed the NT and BL than in the CTR group, particularly in the stimulated fish (D*I, P < 0.001). In addition, both stimulated and placebo fish that received the BL diet showed an increase in hepatic GR activity compared to the CTR group, regardless of the sampling time. Dietary supplementation with AW by-products obtained from G. gracilis cultured under NT and BL conditions showed to improve the inflammatory and antioxidant mechanisms in gilthead seabream in response to a UV-killed bacterial stimulus, having valuable applications for the sustainable use of seaweed toward improving the health and welfare of cultured fish.


Assuntos
Doenças dos Peixes , Gracilaria , Dourada , Alga Marinha , Ração Animal/análise , Animais , Antioxidantes , Dieta/veterinária , Suplementos Nutricionais , Estresse Oxidativo , Photobacterium
18.
Talanta ; 247: 123556, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35609484

RESUMO

Seaweed can bioaccumulate nanomaterials that would be transferred to the trophic chain. This work describes the optimization of a method for the separation of silver nanoparticles (AgNPs) from seaweed using an ultrasound-assisted enzymatic hydrolysis method and ulterior determination by single particle inductively coupled plasma mass spectrometry (SP-ICP-MS). The following parameters affecting the isolation of AgNPs were optimized using a Palmaria palmata (red seaweed) sample previously exposed to AgNPs: type of sonication (bath vs. ultrasonic probe), ultrasound amplitude, sonication time, sonication mode (pulsed vs. continuous sonication), concentration of the enzymes mixture (Macerozyme R-10®), and enzymatic hydrolysis time. The stability of AgNPs during extraction was tested by transmission electron microscopy (TEM) and using a standard of 15 nm of polyvinylpyrrolidone (PVP)-coated AgNPs analyzed by SP-ICP-MS. The analytical performance was evaluated with good results. For total Ag determination, the limits of detection and quantification were 2.2 and 7.7 ng g-1, respectively; and for AgNPs determination, the limits of detection in size and number were 14 nm and 4.34 × 107 part g-1, respectively. Besides, the matrix effect, the repeatability and the analytical recovery were also studied. Finally, the method was applied to the analysis of several red (Palmaria palmata) and green (Ulva sp.) seaweed samples.


Assuntos
Nanopartículas Metálicas , Alga Marinha , Hidrólise , Espectrometria de Massas/métodos , Nanopartículas Metálicas/química , Prata/química , Verduras
19.
Mar Pollut Bull ; 180: 113772, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35623218

RESUMO

Green tides dominated by Ulva prolifera have be present in the Southern Yellow Sea for 15 consecutive years. They not only damage the marine environment, but also cause economic losses to coastal cities. However, there is still no fully effective approach for preventing green tides. In this article, approaches for the prevention of U. prolifera taken over recent years are reviewed. They can be generally divided into physical, chemical, and biological approaches. Physical approaches have been used to control the overwhelming green macroalgae bloom and inhibit the germination of U. prolifera, including physical salvage approach, refrigeration net technology, improved farming methods and raft technology, and modified clay method. These approaches require significant labor and material resources. Many chemical reagents have been used to eliminate U. prolifera early germination and growth, such as oxidative algaecide, acid treatment, heavy metal compounds, antifouling coating, and alkaloids. Chemical approaches have high efficiency, high economic benefit, and simple operation. Presently, biological control approaches remain in the exploratory stage. The verification of pilot and large-scale experiment results in sea areas is lacking, including the application of large organisms and microorganisms to control U. prolifera, and some of the mechanisms have not been thoroughly studied. This article introduces the three types of approaches, and evaluates the advantages and disadvantages of different methods to facilitate the reduction of the green tide bloom scale in the Southern Yellow Sea.


Assuntos
Alga Marinha , Ulva , China , Eutrofização
20.
Mar Pollut Bull ; 180: 113766, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35635882

RESUMO

Sewage-associated plastic wastes, such as wet wipes and cotton bud sticks, commonly wash up on beaches; however, it is unclear whether this represents a public health risk. In this study, sewage-associated plastic waste, and naturally occurring substrates (seaweed and sand), were collected from ten beaches along the Firth of Forth estuary (Scotland, UK) and analysed using selective media for the faecal indicator organisms (FIOs) E. coli and intestinal enterococci (IE), and potential human pathogens (Vibrio spp.). Minimum inhibitory concentration (MIC) analysis was used to determine antibiotic resistance in selected strains. FIOs and Vibrio were more often associated with wet wipes and cotton bud sticks than with seaweed, and there was evidence of resistance to several antibiotics. This work demonstrates that plastics associated with sewage pollution can facilitate the survival and dissemination of FIOs and Vibrio and thus, could present an as yet unquantified potential risk to human health at the beach.


Assuntos
Alga Marinha , Vibrio , Antibacterianos/análise , Praias , Farmacorresistência Bacteriana/genética , Monitoramento Ambiental , Escherichia coli , Humanos , Plásticos/análise , Esgotos/análise , Microbiologia da Água
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