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Seaweed consumption has increased considerably in Europe as a result of new trends in food. The macroelement (Na, Ca, K, Mg) and trace element (B, Ba, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Sr, V, Zn) levels in different species of edible brown seaweeds were determined by inductively coupled plasma optical emission spectrometry (ICP-OES). European Himanthalia elongata species had the highest recorded concentrations of K (57480 mg/kg dry weight). Asian Undaria pinnatifida species had the highest Fe content (58.8 mg/kg dw). Five grams/day of dehydrated seaweed of the Asian U. pinnatifida species mainly contributes to the admissible daily intake of Mg (9.32% adults) and Na (7.05% adults). In any case which exceeds the maximum intake values of any of the elements analyzed, the macro- and trace element levels can vary considerably in a short period of time, so it is necessary to assess the toxic risk in edible seaweeds.

Dynamics of probiotics Lactobacillus rhamnosus LGG, L. reuteri BioGaia, Bifidobacterium animalis subsp. lactis BB12 and B. longum subsp. longum BB536 were investigated during the fermentation of milk supplemented with extracts of Chondrus crispus (CC), Himanthalia elongata (HE), Laminaria ochroleuca (LO), Palmaria palmata (PP), Porphyra umbilicalis (PU), Ulva lactuca (UL) and Undaria pinnatifida (UP). After 24 h at 37 °C, LGG attained counts above 108 cfu/ml in control milk and in milk with all seaweed extracts while BioGaia only attained that level in milk with CC, HE, PP, PU and UL extracts, B12 in milk with UL and UP extracts, and BB536 in milk with CC, HE, PU and UL extracts. In physiological saline, LGG, BioGaia, BB12 and BB536 were respectively stimulated by 4, 0, 5 and 3 seaweed extracts after 24 h at 37 °C and inhibited by 1, 5, 2 and 0 seaweed extracts. Casein and whey proteins added to physiological saline neutralized inhibition caused by UL extract, increasing probiotic counts by 4–5 log cfu/ml, while lactose and citrate had no significant effect. Milk supplementation with seaweed extracts permitted attaining probiotic counts above 108 cfu/ml at the end of fermentation, a result of practical interest for the dairy industry.

10 Pág. Departamento de Tecnología de Alimentos​​, Edible seaweeds Chondrus crispus, Codium fragile, Himanthalia elongata, Ulva lactuca and Undaria pinnatifida, without any treatment (control seaweeds), were stored at 4 °C for 15, 30, 60, 15 and 30 days, respectively, until microbial counts exceeded 7 log cfu/g. High pressure processed (HPP) seaweeds, treated at 400 or 600 MPa for 5 min on day 2 after collection, were held at 4 °C until day 180. At the start of storage, 133 volatile compounds were detected in control seaweeds, with 89, 31, 45, 79 and 69 compounds found in C. crispus, C. fragile, H. elongata, U. lactuca and U. pinnatifida, respectively. Chemical groups including the highest number of compounds were aldehydes (24), alcohols (23), ketones (18), hydrocarbons (17) and benzene compounds (14). At the end of storage, 131 compounds were detected in control seaweeds, including 18 aldehydes, 28 alcohols, 23 ketones, 14 hydrocarbons and 13 benzene compounds, and 164 compounds in HPP-treated seaweeds, including 23 aldehydes, 31 alcohols, 19 ketones, 23 hydrocarbons and 15 benzene compounds. Increases in the levels of alcohols, benzene compounds and S-compounds and decreases in hydrocarbons, aldehydes and acids were recorded during storage of some control seaweeds, and increases in the levels of alcohols, acids and N-compounds and decreases in aldehydes, ketones and furans during storage of some HPP-treated seaweeds. Odour acceptance fell below rejection threshold as early as on day 15 for control U. lactuca while it remained acceptable until day 60 for control H. elongata and until day 180 for all the HPP-treated seaweeds. HPP treatment at 400 to 600 MPa for 5 min, in combination with refrigerated storage, is a useful tool for seaweed preservation, given its beneficial effects on microbial quality and sensory characteristics., This research was supported by project AGL2013-42911-R (Ministerio de Economía y Competitividad, Spain). The courageousness and camaraderie from Ana del Olmo during the performance of this study is acknowledged by the rest of authors

Research is more and more focused on studying and selecting food preservatives of natural origin. In this scenario, algae are an excellent source of bioactive compounds, among which are antimicrobials, whose presence is variable depending on the algal species and environmental conditions. The aim of the present study was to obtain, by a food grade approach, antimicrobial extracts from five species already approved as foods and to test their efficacy in vitro (agar well diffusion assay) and in situ (microbial challenge test) towards foodborne pathogenic bacteria. Moreover, the total phenolic compounds of the extracts were determined in order to evaluate possible correlations with the antimicrobial activity. Strains belonging to Salmonella spp., Listeria monocytogenes, Escherichia coli, Staphylococcus aureus, and Bacillus cereus were considered. Overall, the extracts showed a good antimicrobial activity in vitro towards all the tested microorganisms, especially L. monocytogenes (15 mm of inhibition diameter). The effect of inhibition was monitored during 24, 48 and 120 h showing a good persistence in time. Arthrospira platensis exerted the highest efficacy, further revealed towards L. monocytogenes on salmon tartare as bacteriostatic using 0.45% of the extract and bactericidal using 0.90%. The presence of phenolic compounds could be related to the antimicrobial activity but was not revealed as the main component of this activity. The extract with the highest phenolic content (18.79 &plusmn, 1.90 mg GAE/g) was obtained from Himanthalia elongata. The efficacy, confirmed also in a food matrix, might open perspectives for their application as food preservative.

Algae are a complex, polyphyletic group of organisms, affordable and naturally rich in nutrients, but also valuable sources of structurally diverse bioactive substances such as natural pigments. The aim of this work was to evaluate the polar and non-polar pigment contents of different commercial dried algae (brown: Himanthalia elongata, Undaria pinnatifida, Laminaria ochroleuca, red: Porphyra spp., and a blue-green microalga: Spirulina spp.). The pigment extraction was carried out using different solvents (100% methanol, 100% methanol acid free, 100% ethanol, 90% acetone, N,N-dimethylformamide, dimethyl sulfoxide-water (4:1, v/v) and pH 6.8 phosphate buffer), selected according to their affinity for each class of pigments. Acetone proved to be an efficient solvent to extract chlorophylls from brown and red algae, but not from Spirulina spp. Porphyra spp. presented considerably higher levels of all pigments compared to brown algae, although Spirulina spp. presented significantly higher (p &lt, 0.05) levels of chlorophylls, carotenoids and phycobiliproteins, compared to all macroalgae. The content of fucoxanthin extracted from the three brown algae was highly correlated to the carotenoid content. Within this group, Himanthalia elongata presented the highest fucoxanthin/total carotenoids ratio. Although the yield of extraction depended on the solvent used, the algae studied herein are an interesting source of pigments of great value for a wide range of applications.

Himanthalia elongata is a brown oceanic seaweed rich in bioactive compounds. It could play an important role in food production because of its antimicrobial and antioxidant properties. Three strains belonging to the Lactobacillus casei group (Lactobacillus casei, Lactobacillus paracasei, and Lactobacillus rhamnosus) and a Bacillus subtilis strain were used for the solid-state fermentation of commercial seaweeds, and bacterial growth was monitored using the plate count method. High-pressure processing (HPP) was also employed (6000 bar, 5 min, 5 &deg, C) before extraction. The antimicrobial activity of the extracts was tested in terms of the main food pathogenic bacteria (Salmonella spp., Listeria monocytogenes, Escherichia coli, Staphylococcus aureus, and Bacillus cereus), and the phenolic content was estimated using the Folin&ndash, Ciocalteau method. In addition, targeted UHPLC-MS2 methods were used to unravel the profile of phlorotannins. H. elongata allowed the growth of the L. casei group strains and B. subtilis, showing the fermentability of this substrate. Significant antimicrobial activity toward L. monocytogenes was observed in the extracts obtained from unfermented samples, but neither fermentation nor HPP enhanced the natural antimicrobial activity of this seaweed species. The content in the phenolic compounds decreased because of the fermentation process, and the amount of phenolics in both the unfermented and fermented H. elongata extracts was very low. Despite phlorotannins being related to the natural antimicrobial activity of this brown seaweed, these results did not support this association. Even if fermentation and HPP were not proven to be effective tools for enhancing the useful compounds of H. elongata, the seaweed was shown to be a suitable substrate for L. casei group strains as well as for B. subtilis growth, and its extracts exhibited antimicrobial activity toward foodborne pathogens.

Seaweeds are an ideal food-safe natural source of minerals with a potential use in human nutrition. However, the presence of phytate and different treatments before consumption could modify mineral availability. The content and in vitro mineral availability after a simulated gastrointestinal digestion of wakame (Undaria pinnatifida), nori (Porphyra spp.), sea salad (Ulva lactuca, Palmaria palmata, Undaria pinnatifida, Porphyra spp., Laminaria spp.), and sea spaghetti (Himanthalia elongata) were studied. Experiments were assessed after a soaking treatment of seaweeds with cold (20 °C) or hot (70 °C) water, as usually processing before eating. Moreover, inositol phosphate content was determined in the edible macroalgae and the molar ratio phytate/mineral was used as a predictor of the relative availability of minerals. Overall, edible analyzed seaweeds showed a high Ca, Fe, P, and K contents, highlighting wakame for all the studied minerals. In all cases, soaking in cold water showed the highest soluble and dialyzable mineral fractions. High content of phytic acid (IP6) was observed in sea salad (≈ 25 mg (100 g)−1); meanwhile, sea spaghetti showed the lowest IP6 content (3.9 mg (100 g)−1). The low molar ratios Phy/Ca and Phy/Zn obtained in seaweeds could indicate an adequate availability. However, ratios Phy/Fe could compromise the iron availability in wakame, nori, and sea spaghetti. Results obtained confirm that external factor such as soaking, gastrointestinal digestion, and inositol phosphates can affect the mineral availability. Consumption of edible seaweeds can be recommended for the necessary intake of available minerals and trace elements.

Polysaccharides from the brown seaweed Himanthalia elongata and the red one Gigartina pistillata have been extracted by sequential fractionation based on the solubility in water (F-H2O), hydrochloride acid (F-HCl) and potassium hydroxide (F-KOH), remaining a residue (RES). Their structures have been studied through Fourier-transform infrared spectroscopy (FTIR) and molecular weight by molecular exclusion (HPSEC). Sugar composition and sulphate content were also determined. F-H2O and F-HCl from Himanthalia elongata were rich in fucoidans with an estimated Mw of 926 and 430 × 103 g/mol. Laminarans appeared in the mentioned fractions and possibly xylofucoglycuronans and xylomannans are in F-H2O. F-HCl was poorly fermented with low production of total short chain fatty acids (SCFA) and two poor or non-fermentable low-molecular weight polyuronans (68 and 4 × 103 g/mol) appeared in F-KOH. Carrageenans extracted from Gigartina pistillata presented low or non-fermentability. Xylofucoglycuronans and xylomannans, possibly presented in RES and F-H2O from Himathalia, and laminarans in the last mentioned fraction, seem to be more fermentable. Carragenophytes red seaweeds do not seem to be fermentable whereas brown algae could have major potential fermentability, probably due to the presence of laminarans, xylofucoglycuronans and/or xylomannans.

Subcritical water extraction of Himanthalia elongata and the subsequent acetone fractionation to precipitate crude fucoidans generated a liquid phase which was used to recover alginates with a wide range of viscoelastic features and other soluble extracts with potential biological activities. The precipitated alginate was converted to sodium alginate using an environmentally friendly treatment before being characterized by Fourier transform infrared attenuated total reflectance, nuclear magnetic resonance, high performance size exclusion chromatography and rheological measurements. The cell viability of three human cell lines (A549, HCT-116, T98G) in the presence of the extracts obtained before and after acetone fractionation was assessed. Fractionation with different acetone volumes showed a slight effect in the behavior of the different tested cell lines. Results also indicated a notable effect of the processing conditions on the block structure and molar mass of the extracted biopolymer, with the subsequent impact on the rheological properties of the corresponding gelled matrices. Xunta de Galicia | Ref. ED481B 2018/071 Xunta de Galicia | Ref. ED431F 2020/01 Agencia Estatal de Investigación | Ref. RYC2018-024454-I Ministerio de Economía y Competitividad (España) | Ref. CTM2015-68503-R

WOS:000569919500022; This study was focused on the phenolic content and associated cosmetic activities of seven brown marine macroalgae:Alaria esculenta,Ascophyllum nodosum,Bifurcaria bifurcata,Fucus serratus,Halidrys siliquosa,Himanthalia elongata, andLaminaria ochroleuca, selected for their abundance in Brittany and their phlorotannin production. Phlorotannins were extracted by maceration followed by a liquid/liquid purification to obtain fractions enriched in phlorotannins. Seasonal and yearly variations in phenolic contents were investigated thanks to the Folin-Ciocalteu assay to find the best harvesting season for each species.H-1 nuclear magnetic resonance (NMR) was used to validate the presence of phenolic compounds and to compare the species in terms of phenolic signals, as they produce different phlorotannin molecules. Activities required for cosmetic applications (i.e., radical scavenging, antioxidant, photoprotective, and anti-aging activities) were assessed by in vitro tests. Fucales, especiallyA. nodosum,F. serratus,H. elongata, andH. siliquosa, showed higher phenolic contents than Laminariales.Temporal variations were apparent for five seaweeds with the highest phenolic content, notably in autumn. The phenolic content was high regardless of the season and antioxidant and photoprotective activities were similar to those of commercial molecules, allowing year-round algal harvesting. The anti-aging activity ofA. nodosumandF. serratusfractions was higher than the active tea flavonol, epigallocatechin gallate. These results are promising for the use of abundant marine macroalgae as a source of natural active ingredients for cosmetic applications.

The distribution of macroalgal species along the north and northwest coast of the Iberian Peninsula is in a period of change, during which mostly cold-temperate species have decreased in cover and others have disappeared. On the other hand, other species have increased in abundance. These shifts could be related with the modification of environmental factors that determine species distribution caused by climate change. A standardised sampling methodology was applied at 18 sites along the north coast of Spain in 2011 and 2017. The relationship between the coverage of intertidal macroalgal species and abiotic variables (sea surface temperature, air temperature and significant wave height) was analysed in order to detect possible changes in the historical data. Results suggest a modification in the communities in the inner part of the Bay of Biscay, mostly related to an increase in water and air temperature. Each seaweed group (warm-temperate, cold-temperate, opportunistic and exotic species) showed a different pattern of modification. Coralline algae, Bifurcaria bifurcata and Cystoseira baccata have increased, which may be related to the warming trend. The exotic species Asparagopsis armata has also increased, particularly in the Lower Rias. On the other hand, there was a drastic decrease of the cold-temperate species Himanthalia elongata. Data obtained support the relationship of macroalgae species communities and environment in the context of climate change in this particular area.

Lipophilic compounds of seaweed have been linked to their potential bioactivity. Low polarity solvents such as chloroform, diethyl ether, n-hexane and their various combinations were used to extract the lipophilic antioxidants from brown seaweed namely Himanthalia elongata, Laminaria saccharina and Laminaria digitata. An equal-volume mixture of chloroform, diethyl ether and n-hexane (Mix 4) gave the highest total phenol (52.7 &plusmn, 1.93 to 180.2 &plusmn, 1.84 mg gallic acid equivalents/g), flavonoid (31.9 &plusmn, 2.65 to 131.3 &plusmn, 4.51 mg quercetin equivalents/g), carotenoid (2.19 &plusmn, 1.37 to 3.15 &plusmn, 0.91 &mu, g/g) and chlorophyll content (2.88 &plusmn, 1.08 to 3.86 &plusmn, 1.22 &mu, g/g) in the tested seaweeds. The extracts were screened for their potential antioxidant capacity and the extracts obtained from the selected solvents system exhibited the highest radical scavenging capacity against 2,2&prime, diphenly-1-picrylhydrazyl radical (EC50 98.3 &plusmn, 2.78 to 298.8 &plusmn, 5.81 mg/L) and metal ions (EC50 228.6 &plusmn, 3.51 to 532.4 &plusmn, 6.03 mg/L). Similarly, the same extract showed the highest ferric reducing antioxidant power (8.3 &plusmn, 0.23 to 26.3 &plusmn, 0.30 mg trolox equivalents/g) in all the seaweeds. Rapid characterization of the active extracts by liquid chromatography coupled with photodiode array detector and electrospray ionization tandem mass spectrometry (LC-PDA&ndash, ESI-MS/MS) identified cyanidin-3-O-glucoside, fucoxanthin, violaxanthin, &beta, carotene, chlorophyll a derivatives and chlorophyll b derivatives in the tested seaweed. The study demonstrated the use of tested brown seaweed as potential species to be considered for future applications in medicine, cosmetics and as nutritional food supplement.

Fucoxanthin is a xanthophyll pigment which occurs in marine brown algae (Phaeophyceae). The anti-diabetic, anti-obesity, anti-cancer, and antioxidant properties of fucoxanthin have been widely reported. Macroalgae, particularly brown seaweeds, grow prolifically around Irish coasts, representing a valuable resource of nutraceuticals such as fucoxanthin for functional food applications. The aim of this study was to maximise the solvent extraction yield from three anatomically discrete regions of the seaweed thallus: blade, stipe, and holdfast. Response surface methodology was applied to determine optimum parameters for extraction of fucoxanthin from the seaweed, Fucus vesiculosus, as a model species. A central composite design was applied with four extraction variables: time (30–70 min), temperature (30–70 °C), solvent pH (5.0–9.0), and percentage acetone (30–70 %). Fucoxanthin content of extracts was quantified by high-performance liquid chromatography. Percentage acetone was found to have the most significant (P = 0.0002) effect on fucoxanthin yield, followed by pH (P = 0.028) and temperature (P = 0.049). Multiple response optimisation determined that fucoxanthin yield from F. vesiculosus may be maximised by incubating at 30.0 °C for 36.5 min, pH 5.7, with 62.2 % acetone. Optimised responses were applied to a further nine brown seaweeds; Alaria esculenta, Ascophyllum nodosum, Fucus serratus, Himanthalia elongata, Laminaria digitata, Laminaria hyperborea, Pelvetia canaliculata, Saccharina latissima, and Saccorhiza polyschides. In all species, the blades contained significantly more fucoxanthin than stipes, while holdfasts contained the least. Alaria esculenta blade had the greatest yield (0.870 mg g−1 dry mass), followed by F. vesiculosus blade (0.699 mg g−1) and L. digitata blade (0.650 mg g−1).

The rocky intertidal communities of Ireland contain a mix of cold- and warm-adapted species, however the spatial distribution of these communities has not been investigated in a systematic way. Based on a benthic community dataset collected in 2003 at 63 sites, several statistical analyses were combined with the aims of (i) detecting groups of similar communities and their spatial arrangement, (ii) relating these groups to environmental factors and (iii) identifying the species that drive the different community groups. Sørensen's index suggested two marine community groups, one of the east and south-east (termed ‘east’) and the other in the west, south-west and north (termed ‘west’). A second partition based on combined wave exposure and sea surface chlorophyll comprised four groups, as did a further partition based on combined sea surface and air temperatures. The spatial arrangement of wave height plus chlorophyll conditions agreed reasonably well with the binary marine community partition, but the temperature partition did not. The ‘east’ community appeared to be associated with low wave height and chlorophyll conditions. The species that were most influential to the ‘east’ community wereBalanus crenatus, Austrominius modestusandFucus vesiculosus. The ‘west’ sites were associated with high wave height/low chlorophyll (with some variation in this due to local shelter) and the speciesParacentrotus lividus, Chthamalus stellatus, Alaria esculentaandHimanthalia elongata. A longitudinal pattern rather than one associated with latitude was evident in this marine community and local drivers rather than temperature clines appeared most important for the dominant community patterns.

This study investigated Himanthalia elongata Irish seaweed as a natural resource for antioxidant compounds. The phenolic compounds from the seaweed were extracted using 60% (v/v) aqueous methanol and the crude methanolic extract was purified with liquid–liquid partition (LLP) followed by column chromatography (CC). Among the purified fractions/sub-fractions, LLP-CC-ethyl acetate sub-fraction exhibited the highest DPPH (2,2-diphenyl-1-picrylhydrazyl) scavenging (EC50, 2.4 mg/g) and lipid peroxidation (LPO) scavenging capacity (97.7%). Rapid characterization of the same sub-fraction by LC-DAD–ESI-MS/MS identified a total of 8 phenolic compounds namely hydroxybenzaldehyde (meta/para), phloroglucinol, kaempferol, cirsimaritin, gallic acid 4-O-glucoside, carnosic acid and gallic acid. The purified sub-fractions showed higher antioxidant capacity (P

The biogeographic border between the Eastern and the Atlantic subregions of the Lusitanian Province situated on the west coast of Asturias (N. of Spain) has moved westwards in recent years. A comparative study, consisting in a resurvey of 20 shores sampled in 1977, covering 200 km showed a large-scale change affecting the mid and low eulittoral. Cold-temperate canopy species such as kelps (Laminaria hyperborea, Laminaria. ochroleuca and Saccorhiza polyschides), fucoids (Fucus serratus, Fucus vesiculosus and Himanthalia elongata) and Chondrus crispus have almost disappeared and replaced by warm-temperate species such as Cystoseira baccata, Cystoseira tamariscifolia, Bifurcaria bifurcata and coralline algae (Ellisolandia elongata, Lithophyllum incrustans and Mesophyllum lichenoides). The loss of canopy-species can have consequences for the assemblage, especially in the case of fucoid-dominated assemblages.

In the current scenario of climate change characterized by a generalized warming, many species are facing local extinctions in areas with conditions near their thermal tolerance threshold. At present, the southern limit of the geographical distribution of several habitat-forming algae of cold-temperate affinities is located in the Northwest Iberian Peninsula, and the Rias Baixas may be acting as contemporary refugia at the range edge. Therefore, it is necessary to analyze future changes induced by ocean warming in this area that may induce changes in macroalgae populations. The Delft3D-Flow model forced with climatic data was used to calculate July–August sea surface temperature (SST) for the present (1999–2018) and for the far future (2080–2099). Mean daily SST was used to develop and calibrate a mechanistic geographical distribution model based on the thermal survival threshold of two intertidal habitat-forming macroalgae, namely Himanthalia elongata (L.) S.F.Gray and Bifurcaria bifurcata R. Ross. Results show that H. elongata will become extinct in the Rias Baixas by the end of the century, while B. bifurcata will persist and may occupy potential free space left by the decline in H. elongata.

Edible seaweeds Chondrus crispus (CC, Irish moss), Codium fragile (CF, green sea fingers), Himanthalia elongata (HE, sea spaghetti), Ulva lactuca (UL, sea lettuce) and Undaria pinnatifida (UP, wakame) were high pressure processed (HPP) at 400 or 600 MPa for 5 min and stored at 4 °C for up to 180 days. Viable bacterial counts on day 1 ranged from 4.24 log cfu/g for UP to 6.14 for CC. Estimated shelf life of control CC, CF, HE, UL and UP seaweeds, with the threshold set at 7 log cfu/g, was 7, 30, 60, 3 and 30 days, respectively. HPP treatments extended shelf life of seaweeds until at least day 180, except for CC treated at 400 MPa, until day 90. Most microbiological, physicochemical, colour, texture and enzymatic characteristics of seaweeds varied significantly with HPP treatment and storage time. HPP treatments generally preserved total polyphenol content and antioxidant capacity of seaweeds until day 180. Exceptions were total polyphenol content of HE and UP and antioxidant capacity of CC and UP, which suffered losses close to half of the initial values. HPP showed to be a valid processing technology for extending the shelf life of edible seaweeds under refrigerated storage.

Canopy-forming seaweeds sustain critical ecosystem services in coastal habitats. Around the world, many of these seaweeds are suffering strong declines, mainly attributed to the progressive increase in sea surface temperature, in combination with other stressors due to current global changes. The southernmost part of the NE Atlantic is among those areas most affected by climate change. In this study, we estimated the distributional contractions of seven of the most conspicuous seaweeds from the Atlantic coasts of the Iberian Peninsula using an “Extent of Occurrence” methodology. Overall, during the last three decades, range shifts have been more pronounced east of the Cantabrian Sea than along the western coast of the Iberian Peninsula. In particular, regions with a semi-permanent summer upwelling seem to be critical to the persistence of brown seaweeds, fucoids and kelps. Range contractions of the cold-temperate fucoids were estimated to be ca. 21% and 45% for Himanthalia elongata and Fucus serratus, respectively; and for the kelps Saccharina latissima and Laminaria hyperborea, 6% and 14%, respectively. Range contractions for warm-temperate kelps were estimated to be ca. 13% and 10% for Saccorhiza polyschides and L. ochroleuca, respectively. Finally, a decline in the warm-temperate red algae Gelidium corneum occurred only in the easternmost area of the Cantabrian Sea (Basque Country), leading to a distributional contraction of 7%. We recommend conservation actions to better manage the remnant populations of these canopy-forming seaweeds, and their inclusion in national and regional catalogues of endangered species and on international Red Lists., Sí

This article belongs to the Special Issue Screening of Bioactive Compounds from Marine Sources., Marine organisms are potentially prolific sources of high qualify fatty acids that represent useful leads in the development of new nutraceutical agents. In this work, we investigated the lipid composition of six algae species from the Northwest of Spain (Ulva intestinalis, Ulva lactuca, Fucus vesiculosus,Dictyota dichotoma, Cystoseira baccata and Himanthalia elongata) and compared the antioxidant and antibacterial activity of ethanolic extracts obtained by pressurized liquid extraction (PLE). Furthermore, Fucus vesiculosus (F. vesiculosus) PLE using five solvents of different polarities (hexane, ethyl acetate, acetone, ethanol and ethanol:water 50:50) at three temperatures (80 °C, 120 °C and 160 °C) was investigated. F. vesiculosus ethanolic PLE extract presents considerably higher capacity of inhibiting 50% of DPPH (1,1-diphenyl-2-picryl hydrazyl) (IC50 = 7.17 μg/mL) in comparison with the rest of macroalgae studied. Moreover, the potential antimicrobial activity tested on E. coli and S. aureus shows that F. vesiculosus extract produced the best inhibition (IC50 was 2.24 mg/mL (E. coli) and 1.27 mg/mL (S. aureus)). Furthermore, regarding the different solvents and temperatures used to investigate F. vesiculosus PLE, results showed that this technique using ethyl acetate is a selective method to enrich long chain fatty acids (oleic acid, arachidonic acid and eicosapentaenoic acid) with ω-6/ω-3 ratios close to 2.7., This work was supported by the programme “Atracción de Talento 2016”, Comunidad de Madrid (Spain). Paz Otero is recipient of Comunidad de Madrid Postdoctoral Funding (Grant No. 2016-T2/BIO-1791). Authors are also grateful to project ALIBIRD-CM. S2013/ABI-2728 (2014–2018). Comunidad de Madrid.

The main nutritional/bioactive compounds (protein; aminoacids, AA; fucose; minerals; vitamins B12 and C; and total phenolic content, TPC) of nine commercial algae powders, used as food supplements, were studied. Undaria pinnatifida showed the highest protein/aminoacid contents (51.6/54.4 g 100 g–1). Among brown macroalgae, Himanthalia elongata showed the highest fucose content (26.3 g kg−1) followed by Laminaria ochroleuca (22.5 g kg−1). Mineral contents of 15–24% were observed in the algae, being particularly excellent sources of iodine (69.0–472.0 mg kg−1). Porphyra spp. and Palmaria palmata showed the highest vitamin B12 contents (667–674 µg kg−1). Vitamin C ranged among 490.4–711.8 mg kg–1. H. elongata showed the highest total phenolic content (14.0 g kg–1). In conclusion, the studied algae are excellent sources of protein, AA, minerals, vitamin C and some of them presented particularly high vitamin B12 and fucose contents, which may have a potential use as food supplements.

This study explored Himanthalia elongata brown seaweed as a potential source of dietary fucoxanthin which is a promising medicinal and nutritional ingredient. The seaweed was extracted with low polarity solvents (n-hexane, diethyl ether, and chloroform) and the crude extract was purified with preparative thin layer chromatography (P-TLC). Identification, quantification and structure elucidation of purified compounds was performed by LC-DAD-ESI-MS and NMR (1 H and 13 C). P-TLC led purification yielded 18.6 mg/g fucoxanthin with 97% of purity based on the calibration curve, in single-step purification. LC-ESI-MS (parent ion at m/z 641 [M + H-H2O] +) and NMR spectra confirmed that the purified band contained all-trans-fucoxanthin as the major compound. Purified fucoxanthin exhibited statistically similar (p > 0.05) DPPH scavenging capacity (EC 50:12.9 μg/mL) while the FRAP value (15.2 μg trolox equivalent) was recorded lower (p < 0.05) than the commercial fucoxanthin. The promising results of fucoxanthin purity, recovery and activity suggested that H. elongata seaweed has potential to be exploited as an alternate source for commercial fucoxanthin production. Irish Government under the Technology Sector Research Scheme (Strand III) of the National Development Plan (2007-13)

Seaweed habitats are characterised by constantly fluctuating environmental conditions which can influence the biochemical composition of species. To quantify the natural variability in concentrations and composition of pigments and fatty acids, a seasonal and spatial analysis of ecologically and economically important seaweed species (Fucus serratus, Ascophyllum nodosum, Himanthalia elongata, Laminaria digitata and Palmaria palmata) from Ireland was undertaken. Results revealed both common and species-specific patterns in seasonal and spatial algal composition. Generally, pigment concentrations decreased during summer months and were associated with a higher ratio of xanthophylls to chlorophylls. A similar response was observed regarding the proportions of polyunsaturated fatty acids (PUFA) which also decreased during summer. Concentrations in total fatty acids (TFA) revealed two distinct patterns in the five species investigated. In the two fucoid species, an increase in TFA during summer months was positively correlated with high proportions of monounsaturated fatty acids, implying an accumulation of storage lipids; in the remaining three species, proportions of PUFA were highest during winter and generally followed the seasonal trends of TFA. On a larger, geographical, scale, results demonstrated an influence of sampling location on pigments and fatty acids. Results highlight the complexity of interacting seasonal, spatial and species-specific drivers determining the biochemical composition of seaweeds which influences their value as food source and should be considered when natural stocks are harvested for high-value commercial applications.

Seaweeds are widely distributed throughout the world. Many seaweeds are of commercial importance with some consumed directly or used as an ingredient as they have functional, nutritional and/or organoleptic properties. Consumer acceptance of food is closely related to its sensory properties, of which flavor is of prime importance. A significant contributor to flavor is the aromatic volatile components present. This review focusses on the volatile components identified in commercially important edible macroalgae species consisting of four brown (Himanthalia elongata, Laminaria spp. including L. ochroleuca, and Undaria pinnatifida) and two red species (Porphyra umbilicalis and Palmaria palmata). In excess of 200 volatile compounds have been identified consisting of hydrocarbons, alcohols, aldehydes, ketones, acids, esters, furans, phenols and sulfur- containing compounds, among others present in minor quantities. The extraction/concentration conditions, chromatography and detection methodologies applied varied and impacted on the volatiles identified due to differences in their hydrophobicity, molecular weight and vapor pressure. This review highlights that considerable more information is required to identify volatile aromatic compounds in edible macroalgae and to identify those most likely to impact sensory perception. Such information could be used to aid new product development or widen applications of these seaweeds in the food or beverage sectors.

Seaweeds (Himanthalia elongata and Palmaria palmata) and seaweed extracts were used for formulation of active edible films. Films formulated with H. elongata showed higher total phenols and antioxidant capacity than the films formulated with P. palmate and significant (p ≤ 0.05) higher than those formulated with seaweeds extracts regardless of the specie used. The use of the edible films enriched with seaweeds in the fish burgers controlled significantly pH and water activity changes over storage and reduced the microbial growth, especially in the case of edible films formulated with H. elongata compared to control. In addition, a significant (p ≤ 0.05) reduction of lipid oxidation and enhancement of antioxidant capacity of trout burgers over storage were observed. The use of seaweeds incorporated in edible films seems to be a feasible strategy for increasing the shelf life of fish burgers, products prone to rapid oxidative processes and spoilage.

The aim of this study was to evaluate the potential anticoagulant activity of sulphated polysaccharide-containing extracts of six french edible marine macroalgae. Aqueous extracts of brown (Himanthalia elongata, Laminaria digitata, Ascophyllum nodosum, Fucus vesiculosus), green (Ulva lactuca) and red (Chondrus crispus) macroalgae were prepared and their biochemical properties were determined, including major biomolecules, sulphate and ash contents. The anticoagulant activity of each extract was investigated using different scales from the specific antithrombin-dependent pathway (anti-Xa and anti-IIa) to the intrinsic and/or common (Activated Partial Thromboplastin Time, APTT), extrinsic (Prothrombin Time, PT) or common (Thrombin Time, TT) anticoagulant pathways, and compared with those of commercial anticoagulants, heparin and Lovenox®. Laminaria digitata, Fucus vesiculosus and Chondrus crispus extracts showed a significant APTT anticoagulant capacity, only 5-fold lower than that of Lovenox®, which is a pure low molecular weight heparin used as an anticoagulant agent to prevent pulmonary embolism in patients undergoing surgery.

The volatile fraction of dehydrated edible seaweeds belonging to seven species (Himanthalia elongata, Laminaria ochroleuca, Palmaria palmata, Porphyra umbilicalis, Saccharina latissima, Ulva lactuca and Undaria pinnatifida) was analyzed by gas chromatography–mass spectrometry, after solid-phase microextraction of samples. Thirty-six hydrocarbons, 34 ketones, 28 aldehydes, 23 alcohols, 8 carboxylic acids, 6 halogenated compounds, 4 furans, 3 esters, 2 sulphur compounds, 2 pyrazines, 1 pyridine and 1 amine were detected among the 151 volatile compounds found in seaweeds. There were significant differences between seaweed species for all the volatile compounds. Hydrocarbons reached their highest levels in U. pinnatifida, ketones in P. umbilicalis, aldehydes in P. palmata and P. umbilicalis, alcohols in P. umbilicalis, carboxylic acids in S. latissima, and halogenated compounds in L. ochroleuca and S. latissima. Sensory analysis revealed that P. palmata, U. lactuca and H. elongata were the seaweeds showing the most potent seafood odour and seaweed odour characteristics. © 2016 Elsevier Ltd

Lipophilic compounds present in dichloromethane extracts of five brown macroalgae from the Portuguese coast were analyzed by gas chromatography-mass spectrometry (GC-MS). Their dicarboxylic acids, long-chain aliphatic alcohols, and monoglyceride profile are reported for the first time. Additionally, other new compounds were also first reported: 24-methylene-cholesterol in Himanthalia elongata, Laminaria ochroleuca, and Undaria pinnatifida; desmosterol and brassicasterol in H. elongata, L. ochroleuca, Sargassum muticum, and U. pinnatifida; fucosterol and campesterol in S. muticum; and cholest-5-en-3-ol-(3 beta)-3-phenyl-2-propenoate in Cystoseira tamariscifolia. Brown macroalgae dichloromethane extracts are mainly composed of fatty acids (463.4-3089.0 mg kg(-1) of dry material) and sterols (75.5-442.7 mg kg(-1) of dry material). High amounts of polyunsaturated fatty acids were found, with the omega-6/omega-3 ratios of all species lower than 3. Cystoseira tamariscifolia, H. elongata, and S. muticum showed to be also promising sources of fucosterol. These results seem to uphold the incorporation of these macroalgae in a more balanced diet, as well as their use in the nutraceutical industry, as long as they are coupled with sustainable management of these natural resources.

International audience; Through experimental harvesting, followed by a 12-month monitoring of demographic attributes, we tested the influence of harvesting on the population dynamics of Himanthalia elongata. We further explore the data to test the hypothesis that the canopy would exert a negative effect on the other developmental stages (intraspecific competition) throughout the recovery cycle of the population. This showed that the H. elongata canopy plays a marked seasonal role not by precluding the presence of other developmental stages but by delaying or preventing their growth and development. The removal of the canopy facilitates the transition from one developmental stage to another, eventually permitting a fast recovery of size structure in the population. This study allows us to integrate population dynamics and intraspecific relationships in our understanding of macroalgal recovery patterns.

Light and electron microscopy were used to study the involvement of phenolic compounds in the early development of the Northern Hemisphere fucoids, Fucus serratus (L.), Fucus spiralis (L.) and Himanthalia elongata (L.) S. F. Gray. Phenolic compounds, packaged within physodes are a major cytoplasmic component of brown algae. Physodes accumulate at the zygote periphery early in development and are secreted into the primary zygote wall. At germination, physodes accumulate at the rhizoid tip. Physodes, together with other wall components, contribute to the development of the cell plate. Good evidence already exists for the involvement of phenolic compounds in the development of Southern Hemisphere fucoids, and this study shows that phenolics play a similar role in the Northern Hemisphere. Consequently, their perceived role as herbivore deterrents in Northern Hemisphere species may be a consequence of their role in wall construction.

Polysaccharides present in several seaweeds (Kappaphycus alvarezii, Calliblepharis jubata, and Chondrus crispus—Gigartinales, Rhodophyta; Gelidium corneum and Pterocladiella capillacea—Gelidiales, Rhodophyta; Laurencia obtusa—Ceramiales, Rhodophyta; Himanthalia elongata, Undaria pinnatifida, Saccorhiza polyschides, Sargassum vulgare, and Padina pavonica—Phaeophyceae, Ochrophyta) are analyzed by spectroscopic techniques. The nature of the polysaccharides (with extraction and without any type of extraction) present in these seaweeds was determined with FTIR-ATR and FT-Raman analysis of extracted phycocolloids and ground dry seaweed.

International audience; The soluble and insoluble dietary fibre contents of seven marine algae ('sea vegetables'): wakame (Undaria pinnatifida), hijiki (Hijiki fusiformis), sea spaghetti (Himanthalia elongata), arame (Eisenia bicyclis), sea lettuce (Ulva lactuca), A O nori (Enteromorpha spp), and nori (Porphyra tenera) were determined by the gravimetric method of Prosky et al (J Assoc Anal Chem 1988, 71 1017-1023) following some adaptations. These seaweeds are particularly rich in dietary fibres with total dietary fibre contents varying between 32.7 and 74.6% (on a dry weight basis) of which 51.6 to 85.0% are water soluble. Marine algae appear to be good sources of fibres presenting great chemical, physico-chemical and rheological diversities that may be beneficial in nutrition.