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In-depth metabolic profiling of marine macroalgae confirms strong biochemical differences between brown, red and green algae

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Abstract

In-depth metabolic profiling, also termed metabolomics, provides detailed information about the biochemical phenotype of an organism. Besides improving our understanding of biochemical processes, metabolomics is used for environmental monitoring, natural product discovery, or even chemotaxonomy, among others. However, for marine macroalgae, comparative large-scale metabolomics studies are lacking, even though seaweeds belong to the most important aquatic primary producers. In this study, we present via a broad scale systematic metabolomics survey 391 metabolites from 21 seaweeds species, representing brown, red and green algae. We demonstrate clear differences in metabolite composition of these seaweeds, reflecting their taxonomic classification. We highlight these differences for amino acid, amino acid derivative and peptide metabolites, energy and carbohydrate metabolites, for lipid, fatty acid and sterol metabolites and for secondary metabolites, including selected metabolic pathways such as the urea cycle, the citrate cycle and the glyconeogenesis/glycolysis, besides others. Additionally, we link selected seaweed biochemical properties to potential pharmaceutical and nutraceutical applications.

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... M. stellatus and C. crispus have a higher protein concentration compared to G. pistillata. It is important to note that RA are the group with the highest protein content among marine algae, followed by green algae [13,17]. Protein content in marine algae usually varies from 5-20% of dw (brown algae) while in green and red ones may fluctuate between 10-47% [5,19,57]. ...
... The lipid content evaluation revealed low values. Generally, marine algae do not have high lipid content, it usually ranges between 1-5% dw, however these species possess a high level of PUFAs [13,57]. In this study, the results were very similar between the three species and around 0.1-0.15 ...
... In this study, the results were very similar between the three species and around 0.1-0.15 g/100 g dw, similar to previous results [13,57]. This is a lower value compared with other studies in C. crispus (1-3%) [58] or in M. stellatus (3%) [51], as well as in other RA species such as Acanthophora spicifera and Gracilaria edulis which had 0.48% and 0.72%, respectively [59]. ...
Article
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Citation: Carpena, M.; Caleja, C.; Pereira, E.; Pereira, C.;Ćirić, A.; Soković, M.; Soria-Lopez, A.; Fraga-Corral, M.; Simal-Gandara, J.; Ferreira, I.C.F.R.; et al. Red Seaweeds as a Source of Nutrients and Bioactive Compounds: Optimization of the Extraction. Chemosensors 2021, 9, 132. Abstract: The present work aimed to determine the nutritional composition (ash, protein, fat, carbohydrate content and energy value), phenolic compounds, pigments and organic acids content of three typical red algae from the Northwest of Spain: Chondrus crispus, Mastocarpus stellatus, and Gigartina pistillata; as well as their antioxidant and antimicrobial activities. Furthermore, the present work compared two extraction techniques: conventional heat assisted extraction (HAE) and high pressure assisted extraction (HPAE) to maximize the yield and the concentration of target compounds. Different independent variables were considered for the response study. Time (t) and percentage of ethanol of the solvent (S) were chosen for both techniques and temperature (T) and pressure (P) were used for HAE and HPAE, respectively. The experiments were designed following a response surface methodology (RSM) approach. The obtained results showed a similar nutritional composition between algae samples: low-fat content and high content of proteins, carbohydrates and energy. All tested algae showed good antioxidant and antimicrobial properties. Finally, HEA demonstrated to be the most efficient extraction technique. This study confirms the potential of red algae to be part of the human diet as a source of non-animal protein, due to its nutritional content, phenolic profile, pigments concentration and bioactive properties, which proves that HAE is the optimum technique for the extraction maximization.
... The authors classified all metabolites into seven groups and found that brown algae are second in "amino acids and derivatives" and "carbohydrates" content [13]. Brown algae also had the highest number of "cofactors, prosthetic groups and electron carriers" [13]. ...
... The authors classified all metabolites into seven groups and found that brown algae are second in "amino acids and derivatives" and "carbohydrates" content [13]. Brown algae also had the highest number of "cofactors, prosthetic groups and electron carriers" [13]. ...
... In addition, S. latissima contains a large number of small organic molecules called metabolites. The metabolic profile of S. latissima was recently elucidated using liquid chromatography-mass spectrometry [13]. ...
Article
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This study shows the potential of improving the taste and shelf life of salmon by storing it in conjunction with sugar kelp. The influence of the addition of wet sugar kelp to Atlantic salmon fillet was assessed using a Nuclear Magnetic Resonance (NMR) metabolomics approach. Seaweed treatment caused significant changes in the polar and non-polar metabolic composition of salmon muscle upon its storage. The mutual diffusion of sugar kelp and salmon metabolites caused a significant decrease of the formation of the off-smelling compound trimethylamine and the biogenic amines, along with an increase of umami-related compounds (aspartate and succinic acid). Carotenoid composition of the seaweed-treated samples significantly differs from the reference samples. The amount of wet seaweeds used for the treatment and the time passed after the fish slaughter influence salmon quality parameters.
... Seaweeds or marine macroalgae are photosynthetic nonflowering plant-like organisms that are divided into three major groups based on their dominant pigmentation: brown (Phaeophyceae, approximately 1755 species), red (Rhodophyta, approximately 6000 species), and green algae (Chlorophyta, approximately 1500 species) (West et al. 2016;Guiry and Guiry 2018). More than 3000 different compounds have been identified in seaweeds, indicating a diversity that is linked to their polyphyletic origin and the different marine environments in which they thrive (Leal et al. 2013;Belghit et al. 2017). Among the seaweeds, the brown algae are phylogenetically distant from the red and green algae; whereas the red and green algae originated through the primary endosymbiosis of photosynthetic prokaryotes, the evolution of brown algae included a secondary endosymbiosis event (De Clerck et al. 2012;Groisillier et al. 2014). ...
... Among the four brown algae, S. firma and P. kuromo were nearly clustered by metabolite profiling, matching their taxonomic classification in the same family, the Chordariaceae (Figs. 3, 4a, S3, S8). A previous study performed metabolic profiling on various seaweeds from Norway, including 11 brown algae, 7 red algae, and 3 green algae (Belghit et al. 2017). This study showed that the HCA of 391 metabolites were clustered independently in the brown and red algae clade, but there were two clades of green algae. ...
... The sugar characteristics mainly contributed to the formation of the seaweed groups (Fig. 8). Mannitol is the main constituent in brown algae, which was consistent with a other studies (Rousvoal et al. 2011;Groisillier et al. 2014;Belghit et al. 2017), whereas fructose, sucrose, and glucose are characteristic in green algae (Thompson 1996;Kim et al. 2016). The characteristic metabolites in green algae are similar to that in land plants due to the evolutionary relationship; green plants originated from green algae. ...
Article
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Main Conclusion Among seaweed groups, brown algae had characteristically high concentrations of mannitol, and green algae were characterised by fructose. In red algae, metabolite profiles of individual species should be evaluated. Seaweeds are metabolically different from terrestrial plants. However, general metabolite profiles of the three major seaweed groups, the brown, red, and green algae, and the effect of various extraction methods on metabolite profiling results have not been comprehensively explored. In this study, we evaluated the water-soluble metabolites in four brown, five red, and two green algae species collected from two sites in northern Japan, located in the Sea of Japan and the Pacific Ocean. Freeze-dried seaweed samples were processed by methanol–water extraction with or without chloroform and analysed by capillary electrophoresis- and liquid chromatography-mass spectrometry for metabolite characterisation. The metabolite concentration profiles showed distinctive characteristic depends on species and taxonomic groups, whereas the extraction methods did not have a significant effect. Taxonomic differences between the various seaweed metabolite profiles were well defined using only sugar metabolites but no other major compound types. Mannitol was the main sugar metabolites in brown algae, whereas fructose, sucrose, and glucose were found at high concentrations in green algae. In red algae, individual species had some characteristic metabolites, such as sorbitol in Pyropia pseudolinearis and panose in Dasya sessilis. The metabolite profiles generated in this study will be a resource and provide guidance for nutraceutical research studies because the information about metabolites in seaweeds is still very limited compared to that of terrestrial plants.
... In most of the cases, this will affect their biological activity, their metabolic content and including toxic compounds [9]. For that reason, even that > 3200 compounds have been described in seaweeds, the chemistry of many species remains undescribed [9], although some species could share several metabolites due to their phylogenetic arrangement [13]. In this sense, screening guided by biological assays enabled us to identify the natural sources of bioactive compounds [14][15][16] as well to discriminate between those which are non-toxic, in order to contribute with the first steps in drug discovery [14,17]. ...
... In that regard, metabolomics can be useful to reveal patterns and correlations between seaweeds taxonomy, chemical compositions, and displayed bioactivity rankings [18]. Hence, untargeted analysis along with chemical profiling by accurate mass spectrometry identifies chemotaxonomic correlation of species, and allows putative identification of bioactive compounds as many as possible in one or more species in a particular biological group [9,13,18]. ...
... This could explain the marked differences between extracts of species evaluated in this work and extracts of their congeners. Recently, tools such as metabolomics based on accurate mass spectrometry lead us to have a bigger view of the type and quantity of metabolites in a specific biological sample [13,18], which fluctuations respond to environmental cues, defense strategies and to anthropogenic pressures [18]. Evaluation of chemical profiles using metabolomics tools, PCA and HCA, provide a procedural plan capable of distinguishing the individual characteristic of several seaweeds [13,18]. ...
Article
A key therapeutic strategy to prevent metabolic syndrome is the inhibition of α-amylase and α-glucosidase. Derivatives isolated from naturally-sourced seaweeds may act as inhibitors of these enzymes. The aims of this study are to evaluate in vitro the α-amylase and α-glucosidase inhibition of 45 crude extracts from 31 species of Ochrophyta, Rhodophyta, and Chlorophyta present in Mexican seashores, describe their acute toxicity, and putatively identify some of the potential bioactive compounds by using untargeted metabolomics. Also, active extracts were evaluated in the brine shrimp lethality test. Samples were collected during rainy and dry seasons in the rocky shores of Paraíso, Villa Rica and Muñecos, in Veracruz, Mexico. Crude extracts were obtained by maceration and then tested on both enzymes. Chemical profiling was done by accurate mass spectrometry and data was analyzed using statistical tools. The results showed that seaweeds from Veracruz are sources of α-amylase and α-glucosidase inhibitors. The highest α-amylase and α-glucosidase inhibition (IC 50 values) were observed in Cladophora dalmatica (116.99 ± 11.59, 27.86 ± 2.95 μg mL −1), Ectocarpus siliculosus (679 ± 68.17, 276.86 ± 11.20 μg mL −1), Padina boergesenii (567.01 ± 65.20, 43.89 ± 5.46 μg mL −1) and P. gymnospora (> 1000, 59.92 ± 7.45 μg mL −1) species, respectively. Active extracts were more effective inhibitors of α-glucosidase compared to acarbose (> 1000 μg mL −1), used as drug reference. C. dalmatica showed high toxicity (LC 50 = 37.55 ± 1.04 μg mL −1), whilst the rest of the active extracts did not. Fatty acids and terpenoids were tentatively identified in the active extracts as potential inhibitors of tested enzymes. In conclusion, Mexican seaweeds constitute sources of metabolites that could reduce hyperglycemia postprandial by the inhibition of α-amylase and α-glucosidase. Ochrophyta species are the best sources to look for these inhibitors because their extracts are not toxic and displayed lower α-amylase inhibitory activities.
... These phenolic compounds comprise wide categories from simple compounds like ester-bound and free phenolic acids to highly complicated polymers like condensed lignins and tannins (Constable, 1999;Rotini et al., 2013;Stiger-Pouvreau et al., 2014). Macroalgae are rich in various carbon based components (Holdt and Kraan, 2011;Belghit et al., 2017;Wells et al., 2017) that include polyphenols groups (e.g. phloroglucinols and phlorotannins) and non-polar molecules groups (e. g., tocopherols, sterols, pigments, and triterpenes). ...
... These components showed great biological and pharmacological importance, but they also have anti-nutritional effects (protein-inactivation or metal-chelating properties). Brown macroalgae contain other important metabolites, for example, bromophenols, terpenes, and oxylipins (Pérez et al., 2016;Belghit et al., 2017). ...
... Macroalgae also may contain large amounts of tocopherols, a group of compounds that have vitamin E activity and are strong anti-oxidants. In accordance with Belghit et al. (2017), brown macroalgae have tocopherols in extensive amounts mainly as ? ?-, ??-, ??-, and ??-tocopherols. ...
Article
Marine macroalgae are considered to be alternative promising animal feed resources with numerous advantages, such as high growth rate, exceptional tolerance to be potentially cultivated in marine water and non-competition of arable lands for cultivation, over conventional terrestrial resources. Beyond that, macroalgae are rich exclusive sources of several bioactive components such as laminarin and fucoidan (complex carbohydrates), which are of growing interests for their potential beneficial impacts on health of livestock and fish. Dietary supplementation with algae and algae extracts was found to enhance the immune status and improve growth performance of fish. Positive improvements in productive parameters and general health have been observed due to the use of different macroalgae in fish diets. Also, macroalgae and their extracts are recently introduced as safer alternative prophylactic and therapeutic agents to control the infectious diseases affecting farmed fish. Several studies have shown that marine algae are a suggested source of antibacterial agents against both Gram-negative and Gram-positive pathogenic bacteria. This review highlights the health benefits and the potential application of macroalgae phenolic molecules in fish nutrition. Moreover, this review offers future perspectives on curcumin and its nanoparticles, and their applications in fish nutrition.
... To our knowledge, a simultaneous impact of various metals on physiology has not yet been studied in green macroalgae, but the effect of Cd or Cu alone was studied in red macroalga . Recently, variation in metabolites including fatty acids in various algal lineages was compared (Belghit et al., 2017), but a gap remains on how single and combined metals affect not only fatty acids but also other metabolites in green macroalgae. ...
... groups (Belghit et al., 2017). The total content of fatty acids detected in our work was 16.7 mg/g DW (Fig. 4), which is lower than that seen in green microalgae such as Coccomyxa (ca. ...
... 2% of total fatty acids (Kumar et al., 2010). Though it has recently been suggested that "green seaweeds probably lack the metabolic pathways to produce PUFAs with 20 or more chain carbons" (Belghit et al., 2017), our data and cited data show that at least a smaller amount of these acids is produced in the genus Ulva. Quantitative changes of less accumulated acids showed a trend similar to that occurring in major acids, i.e., a relatively slight impact on SFAs followed by a more pronounced impact on MUFAs, and the impact on PUFAs was the most evident: mainly a higher Cu dose alone and in combination with Cd led to even nondetectable content of seven PUFAs (Table 2). ...
... While essential amino acid levels range from 22% to 44% of the total of brown algae and from 26% to 32% in green algae, red algae has between 14% and 19% [23]. However, according to Belghit et al. [32], the concentration of some amino acids, such as glutamate, ornithine, citrulline, serine, and glycine, are significantly higher in red algae than brown and green algae. The bioavailability of the amino acids that comes from the digestion of red algae protein, which can be affected by various antinutritional agents such as polyphenols, polysaccharides, and glycoproteins. ...
... Belghit et al. [32] analyzed red, brown, and green algae and concluded that monounsaturated and polyunsaturated fatty acids are more concentrated in red and green algae than in brown algae; red algae of the Porphyra genus had a higher content of fatty acids of 20 and 22 carbon atoms; and the oxylipine content was higher in red algae. This latter compound functions as a secondary metabolite, as part of the plant's immune system, and were derived from free fatty acids (mainly linoleic and linolenic). ...
... Seaweeds are subjected to a variety of biotic and abiotic stress factors, and simultaneously they respond against this by regulating their physiological profile, especially carbon (C) and nitrogen (N) metabolism. N-enriched amino acids such as ornithine, glutamate, and citrulline are found in brown algae that help them to tolerate stress in different stress conditions (Belghit et al. 2017). ...
... Typical metabolic pathway for the formation of metabolites possessed by brown algae (glutamate, ornithine, and citrulline) that are involved in the urea cycle succinate, cis-aconitate, and isocitrate) are highly concentrated in brown algae that protect them against oxidative stress. The metabolic pathway of their production is demonstrated in Fig. 13.5 (Belghit et al. 2017). ...
Chapter
The role of microbiome in agroecosystems has evolved due to improvements in microbial diversity analysis methods. The journey of microbial diversity estimation progressed from culture-dependent to culture-independent methods. The culture-dependent methods are important in finding the microbial diversity of different environments; however, they are immensely biased toward the dominant microorganisms present in a community. With the advancement in sequencing techniques and genomics, the community exploration using culture-independent methods has commenced a new understanding of microbial interactions with their surroundings. Molecular studies of different environmental communities have uncovered <1% of the total number of prokaryotic species representing the cultivable fraction. This chapter summarizes the different methods to acquire a microbial diversity that may eventually enhance plant growth in sustainable agriculture and may often play a role in the management of environmental problems. The merits and demerits of the commonly used molecular methods to investigate microbial communities are discussed. The potential applications of next-generation sequencing techniques for a comprehensive assessment of microbial diversity have been illustrated.
... General biochemical pathways, as illustrated in the Kyoto Encyclopedia of Genes and Genomes (KEGG) ( http://www.genome.jp/kegg/ ), were used to assign named metabolites to specific metabolic networks ( Belghit et al., 2017 ). Briefly, the enrichment level of each metabolomic pathway was calculated using Fisher's exact test, and a value of p < 0.05 was considered statistically significant ( Liu et al., 2019 ). ...
... These results showed that SM2 can seriously interfere with the metabolic system of Dictyosphaerium sp. In fatty acid (FA) metabolism, saturated FA tetradecanoic acid and monounsaturated FA hexadecenoic acid were significantly elevated in the algae-SM2 group, indicating that the peroxidation of lipids occurred ( Belghit et al., 2017 ). ...
Article
To improve the efficiency of antibiotic degradation, the photosynergistic performance of bismuth vanadate (BiVO4) with a microalga, Dictyosphaerium sp., was demonstrated under visible-light irradiation for the first time. Sulfamethazine (SM2) was selected as a representative sulfanilamide antibiotic, and the photocatalytic degradation mechanism of SM2 was evaluated in media via the BiVO4–algae system. The hydrothermally synthesized sample was characterized using X-ray powder diffraction, X-ray photoelectron spectroscopy, ultraviolet–visible diffuse reflectance spectroscopy, transmission electron microscopy, Brunauer–Emmett–Teller surface area, and Fourier transform infrared spectroscopy techniques. The results demonstrated that the prepared photocatalyst corresponded to phase-pure monoclinic scheelite BiVO4. The synthesized BiVO4 showed superior photocatalytic properties under irradiation with visible light, and more than 80% of photocatalytic degradation efficiency was obtained by the BiVO4–algae system. Based on quenching experiments, the photocatalytic degradation of SM2 in the BiVO4–algae system was primarily accomplished via the generation of triplet state dissolved organic matter, and hydroxyl radicals played a small role in the degradation process. The direct oxidation of holes made no contribution to the degradation. Metabolomics data showed that a total of 91 metabolites were significantly changed between the two comparison groups (algae–SM2 group vs algae group; algae–BiVO4–SM2 group vs algae–BiVO4 group). The glycometabolism pathways were increased and the tricarboxylic acid cycle was activated when BiVO4 was present. The study provides a distinctive approach to remove antibiotics using visible light in the aqueous environment.
... General biochemical pathways, as illustrated in the Kyoto Encyclopedia of Genes and Genomes (KEGG) ( http://www.genome.jp/kegg/ ), were used to assign named metabolites to specific metabolic networks ( Belghit et al., 2017 ). Briefly, the enrichment level of each metabolomic pathway was calculated using Fisher's exact test, and a value of p < 0.05 was considered statistically significant ( Liu et al., 2019 ). ...
... These results showed that SM2 can seriously interfere with the metabolic system of Dictyosphaerium sp. In fatty acid (FA) metabolism, saturated FA tetradecanoic acid and monounsaturated FA hexadecenoic acid were significantly elevated in the algae-SM2 group, indicating that the peroxidation of lipids occurred ( Belghit et al., 2017 ). ...
Article
To improve the efficiency of antibiotic degradation, the photosynergistic performance of bismuth vana-date (BiVO 4) with a microalga, Dictyosphaerium sp., was demonstrated under visible-light irradiation for the first time. Sulfamethazine (SM2) was selected as a representative sulfanilamide antibiotic, and the photocatalytic degradation mechanism of SM2 was evaluated in media via the BiVO 4-algae system. The hydrothermally synthesized sample was characterized using X-ray powder diffraction, X-ray photoelec-tron spectroscopy, ultraviolet-visible diffuse reflectance spectroscopy, transmission electron microscopy, Brunauer-Emmett-Teller surface area, and Fourier transform infrared spectroscopy techniques. The results demonstrated that the prepared photocatalyst corresponded to phase-pure monoclinic scheelite BiVO 4. The synthesized BiVO 4 showed superior photocatalytic properties under irradiation with visible light, and more than 80% of photocatalytic degradation efficiency was obtained by the BiVO 4-algae system. Based on quenching experiments, the photocatalytic degradation of SM2 in the BiVO 4-algae system was primarily accomplished via the generation of triplet state dissolved organic matter, and hydroxyl radicals played a small role in the degradation process. The direct oxidation of holes made no contribution to the degradation. Metabolomics data showed that a total of 91 metabolites were significantly changed between the two comparison groups (algae-SM2 group vs algae group; algae-BiVO 4-SM2 group vs algae-BiVO4 group). The glycometabolism pathways were increased and the tricarboxylic acid cycle was activated when BiVO 4 was present. The study provides a distinctive approach to remove antibiotics using visible light in the aqueous environment.
... Because very few chemomarkers were identified, these hypothesis should be further investigated and tested. These approaches enabled a better exploration of the chemical speciation or evolution among genus or even at a broader scale, as realized by Belghit et al. (2017) on 21 species belonging to red, green and brown algae. With the increase of shared metabolomics platforms, metabolomic fingerprinting might be applied on other macroalgae and marine organisms, and when coupled to genomics or transcriptomics, it will greatly improve our understanding of adaptive mechanisms involved in multi-stressors environments. ...
... Environmental metabolomics, particularly in aquatic organisms, is a growing field in marine science , and few studies have been carried out on macroalgae (e.g. Belghit et al., 2017;Greff et al., 2017). To the best of our knowledge, no metabolomic-based studies have been performed so far on the response of marine macroalgae to ocean acidification while it has been explored on other marine organisms like corals , marine microbes (Coelho et al. 2015), crustaceans (Hammer et al, 2012) and bivalves (Wei et al, 2015;. ...
Thesis
Les macroalgues marines constituent un riche réservoir de composés, aussi appelés métabolites spécialisés, qui jouent diverses fonctions écologiques et font partie des traits adaptatifs. Leur concentration peut varier en fonction de facteurs biotiques et abiotiques mais peu d’études sur les réponses globales des métabolites (métabolome) sont disponibles. C’est dans ce contexte que s’inscrit cette étude doctorale centrée sur les sources potentielles de variations du métabolome chez une algue brune commune des récifs coralliens, Lobophora. Pour cela, quatre espèces de Lobophora présentant des morphologies et des habitats variés ont été sélectionnées dans le lagon de Nouvelle-Calédonie. Nous avons dans un premier temps cherché à caractériser et identifier des métabolites via des approches de chimie traditionnelle. Les lobophorénols, précédemment identifiés chez L. rosacea, ont été retrouvés chez cette espèce ainsi que des molécules polyoléfines chez toutes les espèces étudiées. Plusieurs tests de bioactivité sur diverses souches biologiques ont été mis en place sur des fractions algales dans une visée de valorisation et des résultats positifs ont été obtenus lors du criblage antibactérien contre Staphylococcus aureus. Dans un deuxième temps, les sources de variations du métabolome ont été étudiées à plusieurs échelles par des approches de métabolomique non ciblée. Il ressort de ces diverses études que le métabolome de Lobophora est hyper-variable. Les espèces présentent une empreinte métabolomique propre, sans variation intra-thalle. Leur métabolome varie à l’échelle spatiale, en fonction des sites d’étude et des habitats testés, et au cours du temps en lien avec les facteurs environnementaux, tels que température et salinité. En outre, des conditions de faible pH entraînent également des changements métabolomiques comme nous avons pu le tester en conditions naturelles (site de Bouraké) et en conditions contrôlées. Parmi les marqueurs chimiques liés à ces conditions changeantes nous avons identifié les lobophorénols et plusieurs de leurs potentiels dérivés, des dérivés d’acides gras oxygénés polyinsaturés et des composés polyoléfines. Bien que la métabolomique ait été appliquée avec succès pour discriminer les espèces ou détecter l’effet d’un stress environnemental, les présents travaux ont également souligné la difficulté à travailler sur le genre Lobophora, riche en graisses et pigments, et la limitation dans l’annotation des marqueurs en raison du peu de références disponibles pour ce groupe d’organismes marins encore peu étudiés via cette approche.
... For instance, several authors quantified Taurine and main amino acids in some green, red and brown algae species [27,32,33], or quantified only Taurine and Homotaurine by HPLC with fluorescence detection in several non-commercial marine macro algae [30]. Hypotaurine was detected by UPLC-MS/MS, but not quantified, in a metabolomic study including red, brown and green algae [34], as well as by NMR in the green alga Ulva lactuca [35]. GABA and Hyp have been previously quantified at low or even trace amounts in several red, green and brown algal species by colorimetric and chromatographic methods, but only in two works both compounds were considered [32,36,37,50]. ...
... For instance, Mehdinia et al. [30] quantified Tau and Htau in several marine macro algae and outlined levels between 0.009 mg/g and 2.5 mg/g for Tau and from 0.0003 mg/g to 0.7 mg/g for Htau. In other previous studies, Hyptau was detected in the green alga Ulva lactuca, but authors did not report quantitative data [23,34,35]. ...
Article
A fast and reliable method for the simultaneous quantification of Taurine, Homotaurine, Hypotaurine and 19 amino acids in algae samples by Ultra-performance liquid chromatography coupled with diode array and tandem mass spectrometry (UHPLC–DAD-MS/MS) was optimized and validated. Target compounds were chromatographically resolved in less than 15 minutes. (ESI)-MS/MS electrospray ionization and pure analytical standards were used to confirm the identity of all analytes, while quantitation was carried out with diode array detection. Validation parameters of the method were satisfactory: Resolution of peak pairs was always higher than 1.55; all analytical curves showed R2 > 0.99, with working ranges between 0.04 mg/g to 33.1 mg/g and 9.13 mg/g to 107 mg/g and the Lack-of-fit test was not significant. The intra and inter-day precision of the method (expressed as relative standard deviation) were lower than 6 % and recovery values ranged between 95% and 105%. The method was demonstrated to be robust to small deliberate variations of seven variables such sample weight, volume of hydrolysis reagent, hydrolysis time and temperature, derivatization time, column temperature and flow rate. The mean expanded uncertainty for all the target compounds were 0.7 mg/g with a coverage factor of 2. Method Limits of detection and quantification varied from 0.005 * 10-3 mg/g to 0.11 * 10-3 mg/g and 0.01* 10-3 mg/g to 0.22 * 10-3 mg/g respectively, allowing the routine determination of these bioactive compounds in algae extracts. Therefore, the method was successfully applied for the quantitative determination of the 22 target compounds in five seaweed commercial samples. Relevant compounds were quantified for the first time in the five algae species, namely: i) Taurine in Gracilaria longissima and Chlorella spp., ii) Gamma-aminobutyric acid in G. longissima and L. japonica, iii) Hydroxyproline in G. longissima, Ulva lactuca, Porphyra spp., and L. japonica and iv) Homotaurine and Hypotaurine in the five species studied
... Several other constituents were found in the macroalgae and distributed in various chemical classes, including ketones, aldehydes, hydrocarbons, and amino acids. The presence of these constituents can be related to several biochemical mechanisms in seaweeds to survive in the Antarctic environment, since these compounds are linked to defense against oxidant agents and ultraviolet radiation, as well as to chemical signaling among individuals [28,29]. ...
... (2017) also detected relevant amounts of L-cysteine in brown and red seaweeds, corroborated by our results [29]. ...
Article
Macroalgae comprise a vast group of aquatic organisms known for their richness in phytochemicals. In this sense, the lipophilic profile of five Antarctic seaweed species was characterized by chromatographic and spectroscopic analysis and their antioxidant and antimicrobial potential was evaluated. Results showed there were 31 lipophilic substances, mainly fatty acids (48.73 ± 0.77 to 331.91 ± 10.79 mg.Kg−1), sterols (14.74 ± 0.74 to 321.25 ± 30.13 mg.Kg−1), and alcohols (13.07 ± 0.04 to 91.87 ± 30.07 mg.Kg−1). Moreover, Desmarestia confervoides had strong antioxidant activity, inhibiting 86.03 ± 1.47% of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical at 1 mg.mL−1. Antimicrobial evaluation showed that extracts from Ulva intestinalis, Curdiea racovitzae, and Adenocystis utricularis inhibited the growth of Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 25923), and Salmonella typhimurium (ATCC 14028) from concentrations of 1.5 to 6 mg.mL−1. Therefore, the evaluated brown, red, and green macroalgae contained several phytochemicals with promising biological activities that could be applied in the pharmaceutical, biotechnological, and food industries.
... Seaweeds are subjected to a variety of biotic and abiotic stress factors, and simultaneously they respond against this by regulating their physiological profile, especially carbon (C) and nitrogen (N) metabolism. N-enriched amino acids such as ornithine, glutamate, and citrulline are found in brown algae that help them to tolerate stress in different stress conditions (Belghit et al. 2017). ...
... The metabolic pathway of their production is demonstrated inFig. 13.5(Belghit et al. 2017). ...
Chapter
Biosorption by marine brown algae is considered to be very effective as the brown algae is found in diverse size and are having better efficiency in removing the heavy metals form wastewater which is one of the most critical problem now a days. Many micro and macroalgae are responsible for the recovery of different heavy metals. The brown seaweeds have the highest sorption capacity or higher rate of bioaccumulation for heavy metal ion than that of red and green seaweeds. Marine algae are fast growing algae and can perform relatively better as it requires a small amount of nutrients, CO2 and sunlight for its survival. The present literature covers the biosorption by marine algae mainly the brown algae which can be used all around the year. The carboxyl acid group present in these biomass is found to be the most dominant as well as most abundant functional group that are followed by fucoidan.
... The primary metabolites are involved in vital mechanisms such as growth, development, reproduction, etc. Both polar and non-polar primary metabolites play important role in the adaptation and management of environmental perturbations [25]. The secondary metabolites are involved in other important roles such as interspecific communication, antimicrobial activity, predation defense and also involved in adaptations to environmental perturbations. ...
... The secondary metabolites are involved in other important roles such as interspecific communication, antimicrobial activity, predation defense and also involved in adaptations to environmental perturbations. Synthesis, accumulation and degradation of the osmolytes and various metabolites are the major responses during salt stress management [25]. Metabolomic studies generate the metabolite fingerprint of an organism and the quantification of these metabolites help to understand the variations in the metabolic profile during stress. ...
Article
Kappaphycus alvarezii is an important red seaweed cultivated as a source of carrageenan and crop growth stimulant. The recurrent salinity fluctuations related to weather variability significantly influence the K. alvarezii cultivation. We report on the evaluation of metabolite changes in K. alvarezii under hypo- (16 ppt), control (32 ppt) and hyper- (48 ppt) saline conditions to unveil the metabolic responses of K. alvarezii under fluctuating salinity. The present study identified a total of 66 different metabolites under studied salinity strengths. The hypo-salinity up-regulated aspartate (0.77 folds) and tyrosine (0.71 folds) and down-regulated phenylalanine (0.51 folds) and proline (0.05 folds). Hyper-salinity up-regulated aspartate (0.64 folds), proline (0.55 folds), serine (0.84 folds) and tyrosine (0.97 folds) in K. alvarezii. Variable importance in the projection (VIP) score plot analysis observed these biomolecules as important metabolites in K. alvarezii under variable saline conditions. Most of the sugars got down-regulated under both saline conditions except mannose which exhibited 0.84 folds up-regulation under hyper-saline condition. K. alvarezii exhibited up-regulation of unsaturated fatty acids under hyper-saline conditions as compared to hypo-saline conditions. These results indicated differential metabolomic responses in K. alvarezii and different mechanisms of salinity acclimatization under control, hypo- and hyper-saline conditions.
... Therefore, the objective of the present study was to evaluate the ruminal and total tract digestibility of AA in different seaweeds harvested in different seasons to determine whether all seaweeds species can be used as an alternative ingredient, source of protein, for dairy cows' ration. We hypothesized that ruminal and total tract digestibility of AA will be higher for red seaweeds as they have been found to contain more protein than green or brown seaweeds (Belghit et al., 2017). ...
... More specifically, the lowest ruminal TAA and EAA degradability in brown seaweeds may be attributed to the presence of phlorotannins, a class of phenolic compounds present only in brown seaweeds and reported to influence ruminal bacterial population that in turn affects fermentation parameters ( Wang et al., 2009). Moreover, cell wall polysaccharides differ between seaweed species, which may participate in the differences in ruminal degradability (Belghit et al., 2017). ...
Article
The potential of seaweeds as alternative protein source was investigated in relation to their amino acid (AA) profiles and the ruminal and total tract digestibility of these AAs. Three red (Mastocarpus stellatus, Palmaria palmata, and Porphyra sp.), four brown (Alaria esculenta, Laminaria digitata, Pelvetia canaliculata, and Saccharina latissima), and two green (Cladophora rupestris. and Ulva sp.) seaweed species were used in this study (hereafter, referred to by Genus name only). All seaweeds were collected in Bodø Northern Norway, during Spring and Autumn in 2014 and 2015, except Ulva, which was only sampled in Autumn of both years, and Saccharina which was not sampled in Spring 2014. All the samples were studied for AA concentration. Six species (Cladophora, Laminaria, Mastocarpus, Palmaria, Porphyra and Ulva) were selected for the more resource demanding in situ study. Species and season interactively affected the content of total AA in crude protein in different seaweeds investigated (P = 0.02), with values ranging from 67.2 for Laminaria in Spring to 90.2 gAA/16 g N for Ulva in Autumn. in situ AA degradability was also species specific. The seasonality of total AA in crude protein of different seaweed species mostly did not affect their ruminal degradability, except for alanine, while species and season interactively affected proline's ruminal degradability. The total tract degradability showed that for Laminaria and Mastocarpus, methionine followed by leucine, isoleucine, histidine and lysine, were protected against rumen degradation. These protections seemed to be acid labile allowing digestion in the lower digestive tract. However, due to high indigestible fractions, these two seaweeds provided low amounts of AA to the intestines. Total tract AA digestibility values were the highest for Porphyra (906 g/kg) followed by Palmaria (843 g/kg) and the green seaweeds. To conclude, Laminaria and Mastocarpus are beneficial sources for bypass protein supply as they contain AA protected against rumen degradation. Based on their amount of AA and their AA degradability, Porphyra, followed by Palmaria and the green seaweeds (Ulva and Cladophora) can be considered as relevant sources of protein for ruminants.
... The study of global metabolic profiles, coupled to ecological data can then provide a better understanding of adaptive abilities of macroalgae. In this perspective, and in order to respond to the different problematics, I choose to carried out ecological and metabolomic monitoring on different natural algal populations of Brittany (France) and Galway bay (Ireland), based on the emergent "eco-metabolomic" approach (Jones et al. 2013;Kumar et al. 2016;Belghit et al. 2017;Peters et al. 2018). In this regard, I have tried to study as many algal metabolites as possible (i.e. ...
... Deux espèces natives communes le long des côtes rocheuses de Bretagne et l'espèce invasive très répandue Sargassum muticum ont été étudiées. (Jones et al. 2013;Kumar et al. 2016;Belghit et al. 2017;Peters et al. 2018). Dans cette optique, j'ai essayé d'étudier le plus grand nombre possible de métabolites d'algues (i.e. ...
Thesis
Marine intertidal macroalgae live in a highly variable environment, currently threatened by human activities which lead to ongoing changes on marine ecosytems worldwide. In this regard, algal populations have to adapt to an evolving environment to avoid disappearance, by migrating or producing particular metabolites for example.Besides, each species has a different adaptive capacity, the species presenting a high phenotypic plasticity being more likely to adapt to future environmental conditions than others. In this context, the aim of this work was to study the acclimation abilities of five macroalgal species (either native or introduced) from Brittany (France), through a one-year monitoring combining both ecological and metabolomic data. The first part focused on red macroalgae and mycosporine-like amino acids. Results suggested that these highly diverse compounds, whose synthesis pathway is not completely elucided, could be multifunctional secondary metabolites. Thus, they could play a key role in the future adaptation of some red algal species such as the native Palmaria palmata, compared to the introduced Grateloupia turuturu.The second part then focused on three species of brown macroalgae (Sargassaceae) and showed that the native Halidrys siliquosa is more threatened than the other native species (i.e. Bifurcaria bifurcata) in the context of global change. Indeed, it is a cold-water affinity species that is all the more threatened as it have to cope both with global change and co-habitation with introduced species such as Sargassum muticum.
... Algae are among the most widespread aquatic, photosynthetic organisms present in both freshwater and marine water [15,16]. Algae are considered an excellent source of secondary metabolites or bioactive compounds [17][18][19]. The cultivation system, growth conditions and growth phases are some prime factors that limit the rate and amount of metabolite production [20][21][22]. ...
Article
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The world has faced the challenges of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) for the last two years, first diagnosed at the end of 2019 in Wuhan and widely distributed worldwide. As a result, the WHO has proclaimed the illness brought on by this virus to be a global pandemic. To combat COVID-19, researcher communities continuously develop and implement rapid diagnoses, safe and effective vaccinations and other alternative therapeutic procedures. However, synthetic drug-related side effects and high costs have piqued scientists’ interest in natural product-based therapies and medicines. In this regard, antiviral substances derived from natural resources and some medicines have seen a boom in popularity. For instance, algae are a rich source of compounds such as lectins and sulfated polysaccharides, which have potent antiviral and immunity-boosting properties. Moreover, Algae-derived compounds or metabolites can be used as antibodies and vaccine raw materials against COVID-19. Furthermore, some algal species can boost immunity, reduce viral activity in humans and be recommended for usage as a COVID-19 preventative measure. However, this field of study is still in its early stages of development. Therefore, this review addresses critical characteristics of algal metabolites, their antioxidant potential and therapeutic potential in COVID-19.
... In recent years, it has been widely cultivated, harvested, processed, and consumed in East-Asian countries. Southern China extensively cultivates and produces seaweeds [1][2][3]. As consumer health awareness increases, the demand for Porphyra in food processing is increasing rapidly. ...
Article
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The influence of harvest time on the photosynthetic protein quality of the red alga Porphyra dentata was determined using label-free proteomics. Of 2716 differentially abundant proteins that were identified in this study, 478 were upregulated and 374 were downregulated. The top enriched Kyoto Encyclopedia of Genes and Genomes (KEGG) and gene ontology (GO) pathways were metabolic processes and biosynthetic pathways such as photosynthesis, light harvesting, and carbon fixation in photosynthetic organisms. Nine important photosynthetic proteins were screened. Correlations among their expression levels were contrasted and verified by western blotting. PSII D1 and 44-kDa protein levels increased with later harvest time and increased light exposure. Specific photoprotective protein expression accelerated P. dentata growth and development. Biological processes such as photosynthesis and carbon cycling increased carbohydrate metabolism and decreased the total protein content. The results of the present study provide a scientific basis for the optimization of the culture and harvest of P. dentata.
... Macroalgae are commonly known as seaweeds and are grouped into three major categories according to their pigmentation-green seaweeds (Chlorophyta), brown seaweeds (Phaeophyta), and red seaweeds (Rhodophyta) [54]. The pigment characteristics of macroalgae are related to their sea habitat, since not all of them need the same amount of light to perform photosynthesis. ...
Article
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Herpes simplex viruses (HSVs) are common human pathogens belonging to the subfamily alpha-herpesvirinae that trigger severe infections in neonates and immunocompromised patients. After primary infection, the HSVs establish a lifelong latent infection in the vegetative neural ganglia of their hosts. HSV infections contribute to substantial disease burden in humans as well as in newborns. Despite a fair number of drugs being available for the treatment of HSV infections, new, effective, and safe antiviral agents, exerting different mechanisms of action, are urgently required, mainly due to the increasing number of resistant strains. Accumulating pieces of evidence have suggested that structurally diverse compounds from marine algae possess promising anti-HSV potentials. Several studies have documented a variety of algal polysaccharides possessing anti-HSV activity, including carrageenan and fucan. This review aimed to compile previous anti-HSV studies on marine algae-derived compounds, especially sulfated polysaccharides, along with their mode of action, toward their development as novel natural anti-HSV agents for future investigations.
... The g-aminobutyrate (GABA) shunt is a metabolic pathway that bypasses two steps of the tricarboxylicacid (TCA) cycle to produce succinate, as an alternative route in plants and mammals, while it has not been extensively studied in bacteria but is thought to play a role in glutamate metabolism, anaplerosis, and antioxidant defense (Bouche et al., 2003;Feehily et al., 2013). In addition, GABA has also been found abundant in many algae species (Belghit et al., 2017), the enrichment of related modules could be caused by algae associations in the gut of algae-eating animals. Prediction of Carbohydrate-Active enZYmes (CAZy) showed a subclade-based grouping as well. ...
Article
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Vibrionaceae is one of the most diverse bacterial families and is currently classified into over 50 clades, some members of which play an important role in the symbiotic relationships with humans and animals. Halioticoli clade, which currently consists of 10 species: 8 species associated with the gut of abalone (symbiotic), 1 species (V. breoganii) from bivalves, and 1 species (V. ishigakensis) from subtropical seawater (planktonic). To accelerate studies in the evolution, ecogenomics, and biotechnology of Halioticoli clade species, the genomic backbones and pangenome analyses based on complete genome sequences are needed. Genome sizes of Halioticoli clade species ranged from 3.5 Mb to 4.8 Mb, with V. ishigakensis the biggest. The evolutionary relationships using multilocus sequence analysis based on eight housekeeping genes and 125 single-copy core genes revealed a division of five sub-clades in this clade; 1) V. breoganii, V. comitans, V. inusitatus and V. superstes, 2) V. ezurae, V. neonatus, and V. halioticoli, 3) V. rarus, 4) V. gallicus, and 5) V. ishigakensis. The pan-genomic analysis combined with function and metabolism estimations showed that the planktonic group (sub-clade 5) contained the greatest number of specific genes, and more genes responsible for carbohydrate metabolisms, especially the genes encoding D-galactonate degradation. These results demonstrated that the genome expanded by acquiring more abilities for utilizing various carbohydrates during the evolution from symbiotic to a planktonic lifestyle. Moreover, according to Carbohydrate-Active enZYmes (CAZy) profiling, genes encoding alginate degrading enzymes (aly), classified into PL6, PL7, PL15, and PL17 were common in the ten genomes, but sub-clade 1 had the most. Meanwhile, sub-clade 1and 5 also possessed abundant genes related to macroalgae substrates degradation (GHs), which are also responsible for the genome expansion of sub-clade 1 and 5.
... It is a good tool to appreciate the chemical diversity among species and can bring complementary information to the phylogenetic data, the unavoidable base for classification. These approaches enabled a better exploration of the chemical speciation or evolution among genus or even at a broader scale, as realized by Belghit et al. (2017) on 21 species belonging to red, green and brown algae. With the increase of shared metabolomics platforms, metabolomic fingerprinting might be applied to other macroalgae and marine organisms, and when coupled with genomics or transcriptomics, it will greatly improve our understanding of adaptive mechanisms involved in multi-stressors environments. ...
Article
Among comparative metabolomic studies used in marine sciences, only few of them are dedicated to macroalgae despite their ecological importance in marine ecosystems. Therefore, experimental data are needed to assess the scopes and limitations of different metabolomic techniques applied to macroalgal models. Species of the genus Lobophora belong to marine brown algae (Family: Dictyotaceae) and are widely distributed, especially in tropical coral reefs. The species richness of this genus has only been unveiled recently and it includes species of diverse morphologies and habitats, with some species interacting with corals. This study aims to assess the potential of different metabolomic fingerprinting approaches in the discrimination of four well known Lobophora species (L. rosacea, L. sonderii, L. obscura and L. monticola). These species present distinct morphologies and are found in various habitats in the New Caledonian lagoon (South-Western Pacific). We compared and combined different untargeted metabolomic techniques: liquid chromatography-mass spectrometry (LC-MS), nuclear magnetic resonance (1 H-NMR) and gas chromatography (GC-MS). Metabolomic separations were observed between each Lobophora species, with significant differences according to the techniques used. LC-MS was the best approach for metabotype distinction but a combination of approaches was also useful and allowed identification of che-momarkers for some species. These comparisons provide important data on the use of metabolomic approaches in the Lobophora genus and will pave the way for further studies on the sources of metabolomic variations for this ecologically important macroalgae.
... They are considered the main storage compounds. The analysis also reported a number of antioxidant organooxy compounds such as gluconoheptolactone that is also a precursor to ascorbic acid biosynthesis (Belghit et al. 2017). The increase in the number of metabolic compounds with the collection intervals in the present investigation might be possibly due to the metabolic switching towards phenological abundance of life cycle stages or seasonal acclimation of alga. ...
Article
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Red seaweed genus Gracilaria is fast replacing Gelidium in global agar trade. Recently, Gracilaria dura from Indian waters has emerged as species of choice due to its quality agarose. Triphasic life cycle provides opportunity for selecting elite cultivar. We hereby reported diversity pertaining to functional traits over three months viz. January, February and March among two distinct life phases tetrasporophyte and female gametophyte. It was evident that functional trait related to growth was distinct in tetrasporophyte than in female gametophytes; while that of survival (antioxidant, proximate composition and pigments) were prominent in female gametophyte. Both the lowest 3.42 ± 0.38 % day-1 (female gametophyte) and highest 5.17 ± 0. 21% day-1 (terasporophyte) were in January with 33% higher growth in latter (F=6.57, p=0.024). Nevertheless, of the survival traits antioxidant potential ranged from 0.51 ± 0.08 mg g-1 FW to 1.1 ± 0.03 mg g-1 FW ascorbic acid equivalent. Besides, female gametophyte collected in March reported 53.60%, 28.40% and 50.40% higher activity than the tetrasporophyte of January, February and March respectively (F=65.85, p<0.0001). The female gametophyte of March showed 23% and 19.40% higher protein content than the tetrasporophyte of January and February respectively (F=25.34, p=0.0003). Sixty-one metabolites were reported of which 29 were common, having sugars as the major portion (77.69% in February to 89.38 % in January) and amine derivatives the least (0.30% in January to 0.51% in February). Studies of bio-ecophysiology of this alga is currently being undertaken by our group.
... It was also observed that the presence of fucose in sulfated polysaccharides from brown algae conferred a higher ferric reducing activity relative to polysaccharides from green algae that do not contain this sugar (e.g., Sargassum wightii vs. Ulva lactuca) [7]; a similar effect is likely to influence the behavior observed in our study. In general, secondary metabolites such as polyphenols are more abundant in brown algae, with some, e.g., 2,4,6-trihydroxybenzoate (a benzoic acid derivative), being unique to this group of macroalgae [38]. It should be stressed that polyphenols are compounds with electrons that can be donated, thus conferring a higher antioxidant response when classified methods are used, including electron transfer such as ABTS and FRAP [39]. ...
Article
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Aqueous seaweed extracts have diverse compounds such as Plant-Growth Regulators (PGRs) which have been utilized in agricultural practices for increasing crop productivity. Algal biomass of Padina durvillaei and Ulva lactuca have been suggested for use as biofertilizers because of plant growth-enhancing properties. This work aimed to identify the main PGRs and antioxidant properties in P. durvillaei and U. lactuca extracts, such as abscisic acid, auxins, cytokinins, gibberellins, jasmonates, and salicylates, to assess their potential use as biofertilizers that improve plant growth and crop yield. Phytochemical analyses of two seaweed extracts showed a significantly higher content of sulfates, flavonoids, and phenolic compounds in P. durvillaei extract, which could be linked to its higher antioxidant activity (DPPH, ABTS, and FRAP) compared to U. lactuca extract. The identification and quantification of PGRs showed two gibberellins (GA1 and GA4), abscisic acid (ABA), indoleacetic acid (IAA), three cytokinins (tZ, IP, and DHZ), jasmonic acid (JA), and salicylic acid (SA) in two seaweed extracts. However, GA4, tZ, and DHZ contents were significantly higher in P. durvillaei compared to U. lactuca extracts. These findings evidence that P. durvillaei and U. lactuca extracts are suitable candidates for use as biofertilizers.
... Metabolite profiling and analysis has a long history in marine macroalgae (Gupta, Thakur, Baghel, Reddy, & Jha, 2014), but has focused on metabolites that are bioactive, pharmaceutically relevant compounds (Davis & Vasanthi, 2011;Greff, Zubia, Payri, Thomas, & Perez, 2017); seasonal variation (Surget et al., 2017); delineating biochemical differences of green, red, and brown algae (Belghit et al., 2017); profiling during reproductive fragmentation (He et al., 2019); and stress, defense, and environmental responses (Gaubert, Payri, Vieira, Solanki, & Thomas, 2019;Gaubert, Rodolfo-Metalpa, Greff, Thomas, & Payri, 2020;La Barre, Weinberger, Kervarec, & Potin, 2004;Ritter et al., 2014). ...
Article
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“Omics” techniques (including genomics, transcriptomics, metabolomics, proteomics, and metagenomics) have been employed with huge success in the improvement of agricultural crops. As marine aquaculture of macroalgae expands globally, biologists are working to domesticate species of macroalgae by applying these techniques tested in agriculture to wild macroalgae species. Metabolomics has revealed metabolites and pathways that influence agriculturally relevant traits in crops, allowing for informed crop crossing schemes and genomic improvement strategies that would be pivotal to inform selection on macroalgae for domestication. Advances in metagenomics have improved understanding of host–symbiont interactions and the potential for microbial organisms to improve crop outcomes. There is much room in the field of macroalgal biology for further research toward improvement of macroalgae cultivars in aquaculture using metabolomic and metagenomic analyses. To this end, this review discusses the application and necessary expansion of the omics tool kit for macroalgae domestication as we move to enhance seaweed farming worldwide.
... Macroalgae are prevalently known as seaweeds and are grouped into three major categories. The classification template is according to their pigmentation that includes red seaweeds (Rhodophyta), green seaweeds (Chlorophyta), and brown seaweeds (Phaeophyta) [22,23]. The microalgae comprise the wide scope of autotrophic organisms, with the majority living as small cells of nearly 3-20 µm. ...
... To date, metabolic analysis of macroalgae species within a diurnal cycle was restricted to Ectocarpus, and mannitol was found to be the likely transient carbon source (Gravot et al., 2010). In Ulva, however, mannitol content appears stable between night and day (Supplemental Fig. S8; Supplemental Dataset 2), highlighting the important metabolic differences between macroalgae species, as demonstrated by a recent study (Belghit et al., 2017). Hence, the metabolite responsible for Ulva night growth remains elusive. ...
... In addition to their evolutionary relevance, red algae also hold commercial significance in various industries due to the fact that they produce huge amounts of oil containing polyunsaturated fatty acids (PUFAs) (Sato et al. 2017). Intriguingly, it has been established that there are several biochemical differences among the groups of red, green, and brown algae (Belghit et al. 2017), and hence the study of the regulatory roles of the miRNA transcriptome might help to understand the molecular causes of this biochemical diversity. ...
Article
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Main conclusion MicroRNA-mediated gene regulation in non-vascular plants is potentially involved in several unique biological functions, including biosynthesis of several highly valuable exclusive bioactive compounds, and those small RNAs could be manipulated for the overproduction of essential bioactive compounds in the future. Abstract MicroRNAs (miRNAs) are a class of endogenous, small (20–24 nucleotides), non-coding RNA molecules that regulate gene expression through the miRNA-mediated mechanisms of either translational inhibition or messenger RNA (mRNA) cleavage. In the past years, studies have mainly focused on elucidating the roles of miRNAs in vascular plants as compared to non-vascular plants. However, non-vascular plant miRNAs have been predicted to be involved in a wide variety of specific biological mechanisms; nevertheless, some of them have been demonstrated explicitly, thus showing that the research field of this plant group owns a noteworthy potential to develop novel investigations oriented towards the functional characterization of these miRNAs. Furthermore, the insights into the roles of miRNAs in non-vascular plants might be of great importance for designing the miRNA-based genetically modified plants for valuable secondary metabolites, active compounds, and biofuels in the future. Therefore, in this current review, we provide an overview of the potential roles of miRNAs in different groups of non-vascular plants such as algae and bryophytes.
... These results are interesting, as different seaweed extracts will have different compound profiles. For example, brown alga has a unique metabolism when compared to green alga as it produces more mannitol instead of sucrose resulting in extracts that may have high amounts of mannitol and sugar alcohols (Belghit et al., 2017). Red and green algae may contain more fucoidans when compared to brown alga (Olsson et al., 2020). ...
Article
Plant parasitic nematode (PPN) control has historically relied on the use of synthetic chemical nematicides, however many are toxic to both human health and the environment. The withdrawal of the more harmful nematicides coupled with increases in soil temperatures and increased occurrence of pests and diseases associated with climate change, may enable PPN to increase in numbers and spread globally. The need for sustainable and environmentally friendly management options is necessary while facing future food security scares in order to feed the ever-growing population. Seaweed extracts have been used for decades in agriculture and horticulture as soil biostimulants, however there is a growing body of evidence to suggest that they could be used to reduce the occurrence of damaging PPN infections. Using meta-analysis, we investigated whether seaweed extracts applied to soil could reduce root knot nematode (RKN) abundance and whether there could be confounding factors that influence their efficacy. We found that seaweed extracts reduce RKN performance and that various factors affected the efficacy of seaweed, including the seaweed species itself and the crop the seaweed was applied to. Ascophyllum nodosum extracts were found to be the most effective. Particular RKN species were more sensitive than others to seaweed species used and, in some cases, specific seaweed species only affected particular RKN species. Different life cycle stages were also differentially susceptible to seaweed application, where both egg hatching and population abundance could be reduced via seaweed use. This research indicates that seaweed extracts could potentially be used to help reduce RKN attack on plants.
... Recently, Chen et al. [57] [55] demonstrated that under environmental stress condition, changes in the nutrient metabolism and metabolic pathway may be strain dependent, which affect overall accumulation of the final product of interest. Similalry, Belghit et al. [61] articulated variation in the metabolites level in different red, green and brown algal species. Brown algae was found enriched with citrate, cis-asconitate, isocitrate and succinate in a TCA cycle. ...
Article
Algae have been seen as a potential source for the production of several high-value metabolites and biofuel. The high cost of nutrients required for algal cultivation may limit the economic viability of such algal-products. Utilizing wastewater as a medium for algae cultivation is widely studied to cut down the biomass production cost. However, such a strategy is limited to biofuel production only. The exploitation of wastewater-grown algal biomass is very challenging when the algal biomass is determined for the production of metabolites suitable for human consumption. Reverse osmosis rejects (ROR) represent a non-toxic, cost-effective, and nutrient-rich growth media for algae cultivation. Unlike other wastewater sources, ROR from a water treatment plant will have a more consistent nutrient load and devoid of toxic components. This review focuses on metabolite production using algae and the potential of ROR as a growth medium for mass-scale algae cultivation. Additionally, the review discusses various reactor designs for algae cultivation and downstream processing, targeting metabolite production. Finally, the study is accompanied by a techno-economic assessment of algal-biorefinery, and future prospects are presented.
... The differences observed in the abundance of PUFAs between the three seaweeds in this study may be an adaptive response from these organisms to seasonal changes in environmental and physiological conditions. In fact, PUFAs play an important role in many biochemical pathways, including regulation of membrane fluidity, electron and oxygen transport, and thermal adaptation and therefore may affect the ability of these organisms to deal with different stressors (Belghit et al. 2017). ...
Article
Algae that are found in the coastal regions are an important food source for humans and animals. They are highly susceptible to the influence of environmental parameters on their chemical composition. Thus, the aim of this study was to analyze the influence of seasons (dry and rainy) and species on the biochemical composition of the seaweeds Ulva fasciata, Crassiphycus corneus, and Sargassum vulgare occurring in tropical environment. It was found that crude protein (10.32–22.93%), total lipids (1.74–4.11%), ash (16.51–36.79%), carbohydrates (23.55–42.24%), and neutral detergent fiber (16.50–25.20%) differed significantly among species (p < 0.05). The essential amino acids, histidine, isoleucine, leucine, lysine, methionine + cysteine, phenylalanine + tyrosine, threonine, tryptophan, and valine were identified. Saturated fatty acids, essential fatty acids, and n-6 polyunsaturated fatty acids (PUFAs) were predominant. The lowest protein and PUFA content were found in C. corneus, whereas U. fasciata contained the highest carbohydrate concentrations. Photosynthetic pigments, phenolic, and mineral compounds (such as high concentrations of Sr and As) were found in S. vulgare. However, all seaweed showed significant concentrations of Mn, Zn, K, and Mg indicating that they can be important sources of minerals in animal feed. The three seaweeds showed susceptibility to seasons (rainy and dry), indicated by the synthesis of chemical constituents that consequently affected biomass composition. However, the results demonstrated that because of their biochemical composition, they have biotechnological potential that could be explored in several industrial sectors, including human and animal nutrition.
... NMR based analyses make possible the unravelling of complex mixtures providing the simultaneous identification of endogenous compounds and xenobiotics without coupling to a separation technique (Sobolev et al., 2005;Barding et al., 2012;Dunn et al., 2013;Girelli et al., 2018). NMR spectroscopy has been used in macroalgae metabolomics mainly for the characterization of species (Gupta et al., 2013;Belghit et al., 2017;Palanisamy et al., 2018) and ecotypes (Greff et al., 2017a) but also to understand the metabolic transitions in response to environmental changes (Gaubert et al., 2019) or biological interactions (Nylund et al., 2011;Greff et al., 2017b). Recently, NMR based-metabolomics was applied to investigate the effects of Cu pollution on an algal species (Zou et al., 2014). ...
... Besides PUFAs, macroalgae are known for being a renewable source of other bioactive compounds that include, for instance sterols, volatile organic compounds and vitamins (Silva et al. 2013;Rodrigues et al. 2015;Berneira et al. 2020). These substances are synthesized as secondary metabolites associated with defense mechanisms and inductors of the organism to the environment (Belghit et al. 2017). ...
Article
Polyunsaturated fatty acids are essential biomolecules to human health since their consumption is associated with decreased risk of cardiovascular, inflammatory and cancer diseases, for instance. Despite largely unexplored, sub-Antarctic macroalgae have a considerable nutraceutical potential since this region is known for its harsh environmental conditions, which forces macroalgae to produce secondary metabolites. Therefore, the aims of this work were to determine the fatty acid profile of Ulva sp., Lessonia flavicans Bory and Pyropia columbina (Montagne) W.A. Nelson collected from different collection sites in the Magellan region. Results showed that macroalgae were comprised of 18 to 24 fatty acids with generally a predominance of saturated fatty acids (SFAs) than unsaturated fatty acids. SFAs comprehended 34.40 ± 0.61 mol% of Lessonia flavicans while Pyropia columbina had 69.06 ± 0.77 mol% mainly in the form of palmitic acid. Polyunsaturated fatty acids were found in concentrations ranging from 15.80 ± 0.56 mol% in Pyropia columbina to 54.93 ± 0.15 in Lessonia flavicans. The nutraceutical potential of these macroalgae was observed as the samples had a ∑n3/∑n6 ratio above the indicated by the World Health Organization. Principal Component Analysis showed that the fatty acid profile is characteristic of each macroalgae being a biochemical marker for the identification of the organisms. Therefore, sub-Antarctic macroalgae comprise a promising renewable source of essential fatty acids, mainly as n3, that are essential to the maintenance of human health.
... Seaweed is marine algae that grows in various types of water [1]. Seaweed is originally non-flowering photosynthetic macroalgae that occurs in streaming sections of oceans, seas and rivers [2]. ...
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Objective Extracts from the brown algae Sargassum micracanthum have documented anti-viral, anti-oxidant, and anti-inflammatory activities as well as potential anti-tumor efficacy against several cancer types. Here, we evaluated the inhibitory effect and molecular mechanisms of methanol extract of S. micracanthum (MESM) on the aggressiveness of human head and neck squamous cell carcinoma (HNSCC) using in vitro cell culture-based models. Design To test the potential efficacy of MESM on the migratory and invasive properties of HNSCC cells, we used wound healing, transwell cell migration and invasion assays. Proteome profiling and functional in silico analysis were applied to investigate the possible modes of action by MESM. We also examined the metabolite profiling of MESM using gas chromatography/mass spectrometry. Results MESM inhibited the motility of human HNSCC cell lines as well as invasiveness without influencing cell survival. Proteome profiling identified 19 oncogenic proteins significantly downregulated by MESM treatment. Protein–protein interaction network and gene ontology analyses revealed that Tie2 and associated angiogenic signaling pathway components were significantly enriched among these downregulated oncogenic proteins, which was confirmed by validating the reduced Tie2 expression in MESM treatment groups. Metabolite profiling of MESM identified six-carbon sugar alcohols such as D-sorbitol and/or D-mannitol as the main bioactive compounds. D-sorbitol and D-mannitol effectively reduced Tie2 expression and the aggressiveness of human HNSCC cell lines. Conclusions These findings suggest that six-carbon sugar alcohols in MESM have promising anti-cancer efficacy for the treatment of human HNSCC and further identify Tie2 signaling components as potential treatment targets.
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