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1.
Braz. j. biol ; 84: e263386, 2024. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1403863

RESUMO

Any solid, unprotected, and undefended surface in the aquatic environment will be fouled. Fouling, on the other hand, can affect a wide range of species that can tolerate some epibiosis. Several others, on the other hand, aggressively keep the epibionts off their body surface (antifouling). Antifouling defenses are built into marine plants like seaweed and seagrass. They do have a distinctive surface structure with tightly packed needle-like peaks and antifouling coverings, which may hinder settling bacteria's ability to cling. Chemical antifouling resistance is most probably a biological reaction to epibiosis' ecological drawbacks, especially for organisms capable of performing photosynthesis. The goal of this study was to see how effective natural compounds derived from littoral seaweeds were in preventing fouling. The brown mussel, an important fouling organism, was evaluated in laboratory bioassays against fifty-one populations' crude organic extracts including fort-two macroalgae species. Antifouling activity, exhibited a distinct phylogenetic pattern, with red macroalgae having the largest share of active species, subsequently brown macroalgae. Antifouling action in green seaweeds has never been significant. Seven species showed some level of induced antifouling defense. Our findings appear to back up previous findings about secondary metabolite synthesis in seaweeds, indicating that in the hunt for novel antifoulants, researchers should concentrate their efforts on tropical red macroalgae.


Resumo contaminada. A incrustação, por outro lado, pode afetar uma ampla gama de espécies que podem tolerar alguma epibiose. Vários outros, por outro lado, mantêm agressivamente os epibiontes fora de sua superfície corporal (anti-incrustante). As defesas anti-incrustantes são construídas em plantas marinhas como algas marinhas e ervas marinhas. Elas têm uma estrutura de superfície distinta com picos semelhantes a agulhas bem compactadas e coberturas anti-incrustantes, o que pode dificultar a capacidade de fixação das bactérias. A resistência química anti-incrustante é provavelmente uma reação biológica às desvantagens ecológicas da epibiose, especialmente para organismos capazes de realizar fotossíntese. O objetivo deste estudo foi verificar a eficácia dos compostos naturais derivados de algas marinhas do litoral na prevenção da incrustação. O mexilhão-marrom, importante organismo incrustante, foi avaliado em bioensaios de laboratório contra extratos orgânicos brutos de 51 populações, incluindo duas espécies de macroalgas. A atividade anti-incrustante exibiu um padrão filogenético distinto, com macroalgas vermelhas tendo a maior participação de espécies ativas, posteriormente macroalgas marrons. A ação anti-incrustante em algas verdes nunca foi significativa. Sete espécies apresentaram algum nível de defesa anti-incrustante induzida. Nossas descobertas parecem corroborar descobertas anteriores sobre a síntese de metabólitos secundários em algas marinhas, indicando que, na busca por novos anti-incrustantes, os pesquisadores devem concentrar seus esforços em macroalgas vermelhas tropicais.


Assuntos
Alga Marinha
2.
Braz. j. biol ; 84: e259721, 2024. tab, graf, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1394122

RESUMO

Plant disease administration is difficult due to the nature of phytopathogens. Biological control is a safe method to avoid the problems related to fungal diseases affecting crop productivity and some human pathogenic bacteria. For that, the antimicrobial activity of the seaweed Sargassum muticum methanol and water extracts were investigated against human bacterial pathogens and fungal plant pathogens. By using 70 percent methanol, the seaweed powder was extracted, feeding additives assay, ultrastructure (TEM). Results revealed significant inhibition of S. muticum methanol extract against Salmonella typhi (25.66 mm), Escherichia coli (24.33 mm), Staphylococcus aureus (22.33 mm) and Bacillus subtilis. (19.66 mm), some fungal phytopathogens significantly inhibited Fusarium moniliforme (30.33mm), Pythium ultimum (26.33 mm), Aspergillus flavus (24.36mm), and Macrophomina phaseolina (22.66mm). Phytochemical investigation of S. muticum extract showed the presence of phenolic and flavonoid compounds. Results suggested that there is an appreciable level of antioxidant potential in S. muticum (79.86%) DPPH scavenging activity. Ultrastructural studies of Fusarium moniliforme hypha grown on a medium containing S. muticum extract at concentration 300mg/ml showed a thickening cell wall, disintegration of cytoplasm, large lipid bodies and vacuoles. In conclusion, our study revealed The antibacterial activity of S. muticum extract significantly against some Gram positive, Gram negative bacteria and antifungal activity against some phytopathogenic and some mycotoxin producer fungi. Flavonoids, phenolic play an important role as antioxidants and antimicrobial properties. Such study revealed that S. muticum methanol extract could be used as ecofriendly biocontrol for phytopathogenic fungi and feeding additives to protect livestock products.


A administração de doenças de plantas é difícil devido à natureza dos fitopatógenos. O controle biológico é um método seguro para evitar problemas relacionados a doenças fúngicas que afetam a produtividade das culturas e algumas bactérias patogênicas ao homem. Para isso, a atividade antimicrobiana da alga marinha Sargassum muticum metanol e de extratos aquosos foi investigada contra patógenos bacterianos humanos e fitopatógenos fúngicos. Usando metanol a 70%, o pó de algas marinhas foi extraído do ensaio de aditivos alimentares, a ultraestrutura (TEM). Os resultados revelaram inibição significativa do extrato metanólico de S. muticum contra Salmonella typhi (25,66 mm), Escherichia coli (24,33 mm), Staphylococcus aureus (22,33 mm) e Bacillus subtilis (19,66 mm). Alguns fitopatógenos fúngicos inibiram significativamente Fusarium moniliforme (30,33 mm), Pythium ultimum (26,33 mm), Aspergillus flavus (24,36 mm) e Macrophomina phaseolina (22,66 mm). A investigação fitoquímica do extrato de S. muticum mostrou a presença de compostos fenólicos e flavonoides. Os resultados sugeriram que há um nível apreciável de potencial antioxidante na atividade de eliminação de DPPH de S. muticum (79,86%). Estudos ultraestruturais da hifa de Fusarium moniliforme cultivada em meio contendo extrato de S. muticum na concentração de 300 mg/ml mostraram espessamento da parede celular, desintegração do citoplasma, grandes corpos lipídicos e vacúolos. Em conclusão, nosso estudo revelou a atividade antibacteriana do extrato de S. muticum significativamente contra algumas bactérias Gram-positivas, Gram-negativas e atividade antifúngica contra alguns fungos fitopatogênicos e alguns produtores de micotoxinas. Flavonoides e fenólicos desempenham papel importante como antioxidantes e propriedades antimicrobianas. Tal estudo revelou que o extrato metanólico de S. muticum pode ser usado como biocontrole ecologicamente correto para fungos fitopatogênicos e aditivos alimentares para proteger os produtos pecuários.


Assuntos
Alga Marinha , Controle Biológico de Vetores , Sargassum , Fungos , Antioxidantes , Anti-Infecciosos
3.
Artigo em Inglês | MEDLINE | ID: mdl-36673724

RESUMO

Macroalgae can be a viable alternative to replace fossil fuels that have a negative impact on the environment. By mixing macroalgae with other substrates, higher quality biogas can be obtained. Such biogas is considered one of the most promising solutions for reducing climate change. In the work, new studies were conducted, during which biogas yield was investigated in a three-stage bioreactor (TSB) during the anaerobic digestion of Cladophora glomerata macroalgae with inoculants from cattle manure and sewage sludge at different organic loading rates (OLR). By choosing the optimal OLR in this way, the goal was to increase the energy potential of biomass. The research was performed at OLRs of 2.87, 4.06, and 8.13 Kg VS/m3 d. After conducting research, the highest biogas yield was determined when OLR was 2.87 Kg VS/m3 d. With this OLR, the average biogas yield was 439.0 ± 4.0 L/Kg VSadded, and the methane yield was 306.5 ± 9.2 L CH4/Kg VSadded. After increasing the OLR to 4.06 and 8.13 Kg VS/m3 d, the yield of biogas and methane decreased by 1.55 times. The higher yield was due to better decomposition of elements C, N, H, and S during the fermentation process when OLR was 2.87 Kg VS/m3 d. At different OLRs, the methane concentration remained high and varied from 68% to 80%. The highest biomass energy potential with a value of 3.05 kWh/Kg VSadded was determined when the OLR was 2.87 Kg VS/m3 d. This biomass energy potential was determined by the high yield of biogas and methane in TSB.


Assuntos
Biocombustíveis , Alga Marinha , Animais , Bovinos , Anaerobiose , Reatores Biológicos , Esgotos , Metano
4.
Food Chem ; 409: 135295, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-36603477

RESUMO

The current consumers' demand for food naturalness is urging the search for new functional foods of natural origin with enhanced health-promoting properties. In this sense, algae constitute an underexplored biological source of nutraceuticals that can be used to fortify food products. Both marine macroalgae (or seaweeds) and microalgae exhibit a myriad of chemical constituents with associated features as a result of their primary and secondary metabolism. Thus, primary metabolites, especially polysaccharides and phycobiliproteins, present interesting properties to improve the rheological and nutritional properties of food matrices, whereas secondary metabolites, such as polyphenols and xanthophylls, may provide interesting bioactivities, including antioxidant or cytotoxic effects. Due to the interest in algae as a source of nutraceuticals by the food and related industries, novel strategies should be undertaken to add value to their derived functional components. As a result, metabolomics is considered a high throughput technology to get insight into the full metabolic profile of biological samples, and it opens a wide perspective in the study of algae metabolism, whose knowledge is still little explored. This review focuses on algae metabolism and its applications in the food industry, paying attention to the promising metabolomic approaches to be developed aiming at the functional characterization of these organisms.


Assuntos
Suplementos Nutricionais , Alga Marinha , Alga Marinha/química , Alimento Funcional , Antioxidantes , Metabolômica
5.
Food Funct ; 14(2): 1133-1147, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36594623

RESUMO

A combination of polysaccharides and tea polyphenols can enhance immune activity synergistically, depending on the type and structure of polysaccharides, but the mechanism remains unknown. This study is aimed to investigate the regulating effects of different seaweed polysaccharide (ι-carrageenan, agarose) and tea polyphenol blends on intestinal flora and intestinal inflammation using an in vitro ascending-transverse-descending colon fermentation system and RAW264.7 cell model. The results showed that seaweed polysaccharides in the presence of tea polyphenol were almost completely degraded at transverse colon fermentation for 36 h. Agarose significantly enhanced the butyric acid production content by increasing the abundance of Lachnospiraceae, whereas agarose and tea polyphenol blends did not have a synergistic effect. On the contrary, ι-carrageenan and tea polyphenol blends synergistically increased the abundance of beneficial bacteria (e.g., Bacteroidetes and Bifidobacterium) and promoted the production of short-chain fatty acids (SCFAs), such as isobutyric acid. Such changes tended to alter the impacts of different seaweed polysaccharides and tea polyphenol blends on intestinal inflammation. Among them, ι-carrageenan and tea polyphenol blends were the most effective in inhibiting lipopolysaccharide-induced NO, ROS, IL-6, and TNF-α production in RAW264.7 cells, indicating the alleviated intestinal inflammation. The results suggest that the seaweed polysaccharide and tea polyphenol blends have prebiotic potential and can benefit intestinal health.


Assuntos
Microbioma Gastrointestinal , Alga Marinha , Humanos , Alga Marinha/metabolismo , Fermentação , Carragenina , Sefarose , Polifenóis/farmacologia , Polissacarídeos/farmacologia , Chá/química , Inflamação
6.
Nat Plants ; 9(1): 1, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36693988

Assuntos
Alga Marinha
7.
Mar Environ Res ; 184: 105858, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36630747

RESUMO

Macroalgal bloom events have been frequent in recent years. Eutrophication and overexploitation fishing may favor blooms through nutrient availability and capturing top predators. We aim to investigate the drivers of the macroalgae blooms and their consequences on the food web of the two tropical coastal ecosystems: Porto do Mangue (with high macroalgae production) and Baía Formosa (control environment, without macroalgae), both exploited by artisanal fisheries in northeastern Brazil. The food webs are modeled using the Ecopath with Ecosim (EwE) approach. Our results suggest that fishing did not favor macroalgae blooms but rather the high concentration of nutrients added to the semi-arid conditions. Furthermore, the macroalgae bloom showed low trophic impact, so much of their biomass is transferred into detritus. However, when it decomposes, this accumulation of matter alters the structure and functioning of the ecosystem, affecting its main fish resources: shrimp and piscivorous fish. Investigating blooms is key to management.


Assuntos
Ecossistema , Alga Marinha , Animais , Cadeia Alimentar , Pesqueiros , Biomassa , Eutrofização
8.
Mar Drugs ; 21(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36662213

RESUMO

The brown macroalgae of the species Rugulopteryx okamurae has reached European waters and the Strait of Gibraltar as an invasive species. The proliferation and colonization of the species in subtidal and intertidal zones of these regions imposes significant threats to local ecosystems and additionally represents a significant socioeconomic burden related to the large amounts of biomass accumulated as waste. As a way to minimize the effects caused by the accumulation of algae biomass, investigations have been made to employ this biomass as a raw material in value-added products or technologies. The present review explores the potential uses of R. okamurae, focusing on its impact for biogas production, composting, bioplastic and pharmaceutical purposes, with potential anti-inflammatory, antibacterial and α-glucosity inhibitory activities being highlighted. Overall, this species appears to present many attributes, with remarkable potential for uses in several fields of research and in various industries.


Assuntos
Feófitas , Alga Marinha , Ecossistema , Biomassa
9.
Mar Drugs ; 21(1)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36662221

RESUMO

Microwave-assisted extraction (MAE) is recognized as a green method for extraction of natural products. The current research aimed to explore the MAE for fucoidans extraction from different brown seaweeds, including Fucus vesiculosus, F. spiralis, and Laminaria saccharina. Following several solvent-extraction pre-treatment steps and MAE optimization, the algal biomasses were extracted in a ratio of 1:25 in 0.1 M HCl containing 2 M CaCl2 for 1.0 min. The results showed that L. saccharina's extract was different from the others, regarding the highest sugar content reached 0.47 mg glucose equivalent/mg extract being confirmed by monosaccharide composition analysis and the lowest fucoidan content and sulfation degree at 0.09 mg/mg extract and 0.13, respectively. Moreover, these findings were confirmed by tentative structural elucidation based on Fourier-transform infrared spectrometry which also showed a different spectrum. However, the MAE enhanced melanoidins formation in products, which was confirmed by the intense band at 1420 cm-1. Interestingly, the results of monomeric composition showed that fucoidan extract by MAE from F. vesiculosus belonged to sulfated galactofucans which are known for their potential bioactivities. Furthermore, the cytotoxic activity of the four fucoidans in concentrations ranging from 4.9 µg/mL to 2500 µg/mL was investigated and correlated with the chemical characterization showing that F. vesiculosus_MAE fucoidan was the most potent and safest. The current research revealed the chemical heterogeneity of fucoidans regarding taxonomical class and used greener extraction method of fucoidans toward the achievement of the UN sustainability goals.


Assuntos
Antineoplásicos , Fucus , Feófitas , Alga Marinha , Micro-Ondas , Polissacarídeos/farmacologia , Polissacarídeos/química , Alga Marinha/química , Feófitas/química , Fucus/química
10.
PLoS One ; 18(1): e0279699, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36662876

RESUMO

Macroalgae are an important component of coral reef ecosystems. We identified spatial patterns, environmental drivers and long-term trends of total cover of upright fleshy and calcareous coral reef inhabiting macroalgae in the Great Barrier Reef. The spatial study comprised of one-off surveys of 1257 sites (latitude 11-24°S, coastal to offshore, 0-18 m depth), while the temporal trends analysis was based on 26 years of long-term monitoring data from 93 reefs. Environmental predictors were obtained from in situ data and from the coupled hydrodynamic-biochemical model eReefs. Macroalgae dominated the benthos (≥50% cover) on at least one site of 40.4% of surveyed inshore reefs. Spatially, macroalgal cover increased steeply towards the coast, with latitude away from the equator, and towards shallow (≤3 m) depth. Environmental conditions associated with macroalgal dominance were: high tidal range, wave exposure and irradiance, and low aragonite saturation state, Secchi depth, total alkalinity and temperature. Evidence of space competition between macroalgal cover and hard coral cover was restricted to shallow inshore sites. Temporally, macroalgal cover on inshore and mid-shelf reefs showed some fluctuations, but unlike hard corals they showed no systematic trends. Our extensive empirical data may serve to parameterize ecosystem models, and to refine reef condition indices based on macroalgal data for Pacific coral reefs.


Assuntos
Antozoários , Alga Marinha , Animais , Recifes de Corais , Ecossistema , Temperatura
11.
Food Chem ; 409: 135301, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-36587516

RESUMO

Preservative is of importance to retard fruit deterioration and prolong the shelf-life. The suitability of using water-soluble polysaccharide extracted from waste macroalgae Enteromorpha prolifera (EPP) for cherry tomato preservation was evaluated. As compared with the control, the EPP-treated cherry tomatoes exhibited better fruit appearance, lower disease index and rot index during storage. Around 47 % EPP-treated cherry tomatoes were commercially acceptable after 36 days, which was however only 15.6 % for untreated cherry tomatoes, indicating the satisfactory preservation effectiveness of EPP-rich solution for cherry tomatoes. The post-extraction residue was commonly underutilized, we herein attempted to employ an emerging thermochemical conversion technique, hydrothermal liquefaction, to produce crude bio-oil (biocrude) from post-extraction E. prolifera. A biocrude yield of ∼23 wt% (dry-ash-free, daf) was obtained, and fatty acids and phenolics were identified to be the two main components in biocrude. The biocrude contained ∼70 % carbon and the higher heating value was ∼30 MJ/kg.


Assuntos
Petróleo , Alga Marinha , Ulva , Biocombustíveis , Água , Temperatura
12.
Bull Environ Contam Toxicol ; 110(2): 51, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36720730

RESUMO

Ecological effects in marine living can be understood via the determination of antioxidant molecules in aquatic organisms against pollutants. This study aims to evaluate the radionuclides and trace element stress with response molecules. Cystoseira crinita and Halopteris scoparia have been chosen as study materials because of their susceptibility to pollution. The radionuclides 210Po, 238U, 232Th and 40K and trace elements Al, Fe, Mn, Cr, As, Zn and Pb levels were analysed as well as antioxidants and antioxidant enzymes in two brown algae, seasonally. Marine pollutants in terms of radionuclides and trace elements were correlated with antioxidant molecules in these species and may be used as biomarkers for assessing the radioactive stress. The 210Po and Mn concentrations in C. crinita seem to activate catalase (CAT) and superoxide dismutase (SOD) enzyme activities while 210Po concentrations inclined the proline amount in H. scoparia. This study demonstrated the radiation stress-induced the antioxidant defence system in macroalgae, the primary producers of the marine environment.


Assuntos
Poluentes Ambientais , Alga Marinha , Oligoelementos , Antioxidantes , Radioisótopos
13.
J Agric Food Chem ; 71(4): 2183-2196, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36669856

RESUMO

Red seaweeds (Rhodophyta) are becoming increasingly important as a food and medicine source in blue biotechnology applications such as functional foods, feeds, and pharmaceuticals. Compared to fatty acid composition and sterols, the lipidome in red seaweeds is still in an early disclosure stage. In this study, the lipidomes of four red seaweeds (Gracilaria sjoestedtii, Gracilaria verrucosa, Gelidium amansii, and Chondrus ocellatus) collected from the coastal area in north China were characterized using reversed-phase liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (RPLC-Q-TOF). Hundreds of lipid molecular species including glycolipids, phospholipids, sphingolipids, glycerolipids, and betaine lipids were identified and quantified. Novel lipids with unique molecular structures such as glucuronosyldiacylglycerols (GlcADG), head-group acylated GlcADG (acGlcADG), and hexose-inositol-phosphoceramides (Hex-IPC) were discovered in red seaweeds for the first time, greatly expanding our knowledge on glycolipids and sphingolipids in seaweeds. Glycolipids were the dominant components (45.6-67.7% of total lipids) with a high proportion of polyunsaturated fatty acids (PUFA) including arachidonic acid (AA) and eicosapentaenoic acid (EPA), indicating the potential nutritional value of the four red seaweeds. The investigated red seaweeds showed a distinctive sphingolipid profile with the t18:1 being the predominant LCB in Cer (41.1-71.5%) and HexCer (91.3-97.9%) except for Gelidium amansii, which had the highest proportion of t18:0. Comparison of lipid profiles among the four red seaweeds revealed that AA- and EPA-glycolipids are good lipid markers for the differentiation of red seaweed samples. The AA proportion in glycolipids of Gracilaria genus was much higher than Gelidium genus and Chondrus genus. This study acquired comprehensive lipid profiles from four red seaweeds, revealing the uniqueness of natural biochemical fingerprints of red seaweeds and further promoting their utilization.


Assuntos
Rodófitas , Alga Marinha , Lipidômica , Alga Marinha/química , Rodófitas/química , Ácidos Graxos , Glicolipídeos , Esfingolipídeos
14.
Food Res Int ; 163: 112221, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36596150

RESUMO

Seaweed, an important food resource in several Asian countries, contains various metabolites, including sugars, organic acids, and amino acids; however, their content is affected by prevailing environmental conditions. This review discusses seaweed metabolomics, especially the distribution of primary and functional secondary metabolites (e.g., carotenoids, polyphenols) in seaweed. Additionally, the effects of global warming on seaweed metabolite profile changes are discussed. For example, high temperatures can increase amino acid levels in seaweeds. Overall, understanding the effects of global warming on seaweed metabolite profiles can be useful for evaluating the nutritional composition of seaweeds as food. This review provides an overview of recent applications of metabolomics in seaweed research as well as a perspective on the nutrient content and cultivation of seaweeds under climate change scenarios.


Assuntos
Alga Marinha , Alga Marinha/química , Mudança Climática , Polifenóis , Verduras , Nutrientes
15.
Adv Colloid Interface Sci ; 311: 102829, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36603300

RESUMO

Nanotechnology has opened a new frontier in recent years, capable of providing new ways of controlling and structuring products with greater market value and offering significant opportunities for the development of innovative applications in food processing, preservation, and packaging. Macroalgae (MAG) are the major photoautotrophic group of living beings known as a potential source of secondary metabolites, namely phenolic compounds, pigments, and polysaccharides. Biosynthesis based on the abilities of MAG as "nanobiofactories" targets the use of algal secondary metabolites as reducing agents to stabilize nanoparticles (NPs). Nowadays, most of the studies are focused on the use of metal (Ag, Au) and metal-oxide (CuO, ZnO) NPs derived from algae. The eco-friendly biosynthesis of metal NPs reduces the cost and production time and increases their biocompatibility, due to the presence of bioactive compounds in MAG, making them suitable for a wide variety of applications. These compounds have been attributed to the antimicrobial and antioxidant properties responsible for their application through innovative technologies such as nanoencapsulation, nanocomposites, or biosensors in the food industry. Nevertheless, toxicity is a key factor that should be considered, so the applicable regulation needs to guarantee the safe use of metal NPs. Consequently, the aim of this review will be to compile the available information on MAG-mediated metal NPs, their biosynthesis, and potential food applications.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Alga Marinha , Óxido de Zinco , Metais , Alimentos , Plantas
16.
Environ Monit Assess ; 195(2): 301, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36645500

RESUMO

Since untreated wastewater from hospitals and residential areas is being discharged directly into surface waterways, pharmaceutical contaminants have been shown to be higher in many countries. Therefore, the development of novel and effective techniques to extract antibiotic substances from wastewater is of utmost importance. The present work aims at the use of green Pithophora macroalgae to remove levofloxacin antibiotic from an aqueous solution through biosorption. Biosorption is an economical and eco-friendly method for treating wastewater. The macroalgae were dried, grounded, and used as biosorbent to remove the levofloxacin (LVX) antibiotics from the aqueous solution. The influence of operating conditions such as initial antibiotic concentration, biosorbent dosage, agitation speed, pH, and temperature was studied. The biosorbent was characterized by FTIR, SEM, and point zero charge. The experimental data were evaluated using Langmuir and Freundlich isotherms. The experimental data best fit the Freundlich isotherm model (R2 = 0.969), while the kinetic model for the experiment follows the pseudo-second-order (R2 = 0.998) with a maximum biosorption capacity of 17.8 mg/g. Maximized removal of LVX occurs at favorable conditions of 298 K temperature, 150 mg/L initial concentration of antibiotic, 0.5 g sorbent dose, and 6.5 pH. The calculated thermodynamic parameters reveal that the biosorption of LVX antibiotics occurs by an endothermic process. This study deduces that Pithophora macroalgae biomass proved to be an effective biosorbent for biosorption of LVX antibiotics and may be a novel alternative method for antibiotics removal from aqueous solutions.


Assuntos
Clorófitas , Alga Marinha , Poluentes Químicos da Água , Levofloxacino , Antibacterianos , Biodegradação Ambiental , Cinética , Poluentes Químicos da Água/análise , Adsorção , Monitoramento Ambiental , Termodinâmica , Biomassa , Concentração de Íons de Hidrogênio
17.
Poult Sci ; 102(2): 102361, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36512874

RESUMO

Despite being touted as a rich source of nutrients and functional bioactive compounds, the amount of brown seaweed (Ecklonia maxima) that can be included in diets of Boschveld indigenous chickens is unknown. This study, therefore, investigated the effect of feeding graded levels of brown seaweed meal (BSM) on apparent nutrient digestibility, growth performance, and physiological and meat quality parameters in Boschveld cockerels. A total of 225, five-wk-old Boschveld cockerels (316.4 ± 23.01 g live weight) were raised on 5 isoenergetic and isonitrogenous experimental diets formulated by incorporating BSM in a standard grower diet at a concentration of 0 (BSM0), 20 (BSM2), 40 (BSM4), 60 (BSM6), and 80 g/kg (BSM8). Feeding graded levels of dietary BSM induced neither quadratic nor linear effects (P > 0.05) on apparent nutrient digestibility, growth performance, hematological parameters, and meat quality characteristics in Boschveld cockerels. However, it resulted in linear increases for overall feed intake (R2 = 0.397; P = 0.021), ceca weight (R2 = 0.417; P = 0.013), duodenum length (R2 = 0.537; P = 0.04), and small intestine length (R2 = 0.305; P = 0.041). Negative quadratic responses were recorded for alanine aminotransferase (R2 = 0.530; P = 0.0009) and ileum length (R2 = 0.457; P = 0.045) as BSM levels increased. In conclusion, dietary inclusion of BSM improved feed intake and some internal organ sizes, altered alanine transaminase levels, but had no significant effect on apparent nutrient digestibility, growth performance, and carcass and meat quality attributes of Boschveld indigenous cockerels.


Assuntos
Alga Marinha , Animais , Masculino , Galinhas/fisiologia , Dieta/veterinária , Nutrientes , Carne/análise , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Digestão/fisiologia , Suplementos Nutricionais
18.
Sci Total Environ ; 863: 160727, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36502976

RESUMO

Marine bioinvasions are of increasing attention due to their potential of causing ecological and economic loss. The seaweed Gracilaria vermiculophylla has recently invaded the Baltic Sea, where, under certain conditions, it was found to outcompete the native alga Fucus vesiculosus. Parasites of grazers and temperature are among the potential factors which might indirectly modulate the interactions between these co-occurring algae through their single and combined effects on grazing rates. We tested the temperature and parasitism effects on the feeding of the gastropod Littorina littorea on F. vesiculosus vs. G. vermiculophylla. Uninfected and trematode-infected gastropods were exposed to 10, 16, 22, and 28 °C for 4 days while fed with either algae. Faeces production was determined as a proxy for grazing rate, and HSP70 expression, glycogen and lipid concentrations were used to assess the gastropod's biochemical condition. Gracilaria vermiculophylla was grazed more than F. vesiculosus. Trematode infection significantly enhanced faeces production, decreased glycogen concentrations, and increased lipid concentrations in the gastropod. Warming significantly affected glycogen and lipid concentrations, with glycogen peaking at 16 °C and lipids at 22 °C. Although not significant, warming and trematode infection increased HSP70 levels. Increased faeces production in infected snails and higher faeces production by L. littorea fed with G. vermiculophylla compared to those which fed on F. vesiculosus, suggest parasitism as an important indirect modulator of the interaction between these algae. The changes in the gastropod's biochemical condition indicate that thermal stress induced the mobilization of energy reserves, suggesting a possible onset of compensatory metabolism. Finally, glycogen decrease in infected snails compared to uninfected ones might make them more susceptible to thermal stress.


Assuntos
Alga Marinha , Caramujos , Animais , Temperatura , Homeostase , Lipídeos
19.
Mar Pollut Bull ; 186: 114435, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36493517

RESUMO

A yearlong study was conducted to assess the impact of an oil spill on macrobenthos of rocky intertidal zone of Uran, India and its recovery processes, by comparing impacted site with a reference. Immediate acute effects observed were elevated sediment hydrocarbons, absence of macroalgae and amphipods, mass mortality of macrofauna and dominance of the opportunistic nereid, Namalycastis senegalensis. As the hydrocarbons reduced at the impacted site by ~50 % within three months, gradual re-appearance of macroalgae and re-colonization of amphipods (51.4 %) and sensitive polychaetes (7 %) indicated that the recovery was well underway. The amphipod, Allomelita pellucida proved to be a potential indicator of oil contamination. BOPA correlated with sediment hydrocarbons and performed effectively as the extant macrobenthic communities had sufficient representation of Polychaeta and Amphipoda. Notwithstanding the distinct initial impacts of the oil spill, comparable macrobenthic assemblages comprised of sensitive species at both sites after a year confirmed complete recovery.


Assuntos
Anfípodes , Poluição por Petróleo , Poliquetos , Alga Marinha , Animais , Poluição por Petróleo/análise , Sedimentos Geológicos , Hidrocarbonetos , Ecossistema , Monitoramento Ambiental
20.
Bioresour Technol ; 369: 128448, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36513304

RESUMO

Sargassum spp. is a biomass that can potentially use as an alternative for bioethanol production. Hydrothermal processes (liquid hot water and steam explosion pretreatment) were carried out at different operational conditions. Enzymatic hydrolysis performed a preliminary test with different ratios 1:1 and 1:2 (cellulases and hemicellulases) of enzyme loading, once selected 1:2 ratio was obtained conversion yield of 99.91% and therefore carried a scale-up in stirred bioreactor getting 95.92% saccharification yield. Pre-simultaneous saccharification and fermentation strategy was performed in a continuous stirred tank bioreactor (CSTBR), producing ethanol yield of 57.69%, and for simultaneous saccharification and fermentation strategy was performed in a bubble column reactor was 71.37% ethanol yield. The energy efficiency was analyzed in different scenarios; the best data was 30.19 (gsugar/MJ) in the bioreactor enzymatic hydrolysis process. This development allows for establishing the conditions for a third-generation biorefinery on a circular bioeconomy using Sargassum biomass.


Assuntos
Sargassum , Alga Marinha , Vapor , Biomassa , Água , Hidrólise , Fermentação , Etanol , Biocombustíveis
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