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The inclusion of seaweeds in daily-consumption food is a worthy-of-attention challenge due to their high nutritional value and potential health benefits. In this way, their composition, organoleptic profile, and toxicity must be assessed. This work focuses on studying the volatile organic compounds (VOCs) emitted by three edible seaweeds, Grateloupia turuturu, Codiumtomentosum, and Bifurcariabifurcata, with the aim of deepening the knowledge regarding their organoleptic profiles. Nine samples of each seaweed were prepared in glass vials, and the emitted headspace was analyzed, for the first time, with a gas chromatography—ion mobility spectrometry device, a highly sensitive technology. By statistically processing the collected data through PCA, it was possible to accurately differentiate the characteristic patterns of the three seaweeds with a total explained variance of 98%. If the data were pre-processed through PLS Regression, the total explained variance increased to 99.36%. The identification of 13 VOCs was accomplished through a developed database of compounds. These outstanding values in addition to the identification of the main emissions of VOCs and the utilization of a never-before-used technology prove the capacity of GC-IMS to differentiate edible seaweeds based solely on their volatile emissions, increase the knowledge regarding their organoleptic profiles, and provide an important step forward in the inclusion of these highly nutritional ingredients in the human diet.

As macroalgas são organismos fotossintéticos, muito diversificados. A espécie Gracilaria gracilis, bem como o Codium tomentosum, são comestíveis e apresentam compostos bioativos de elevado interesse, com diversas aplicações em diferentes áreas (alimentar, cosmética, entre outras). Embora não sejam atualmente utilizadas de forma ampla na agricultura, as macroalgas são usadas há já muito anos como bioestimulantes de plantas. Recentemente, ressurgiu um novo interesse nas aplicações agrícolas das macroalgas, relacionado com a procura crescente de produtos que não prejudicam o ambiente e que tornam a produção vegetal mais rentável e sustentável. As macroalgas apresentam na sua constituição, polissacarídeos e hormonas vegetais, (tais como as auxinas, as citocininas, o etileno, as giberelinas e o ácido abscísico), substâncias conhecidas por desempenharem um papel relevante no desenvolvimento e fisiologia das plantas. São também ricas em proteínas, fibras, vitaminas e minerais. O principal objetivo deste trabalho foi a determinação do potencial bioestimulante de extratos de macroalgas, com especial ênfase no seu efeito sobre a germinação e o crescimento de plantas. Adicionalmente, foi testado o potencial aumento da resistência ao stress térmico e ao stress salino. O efeito bioestimulante foi testado em duas espécies agrícolas: alface (Lactuca sativa L.) e tomate (Solanum lycopersicum L.). Foi possível concluir que, na maioria dos ensaios, as sementes expostas aos extratos de macroalgas das espécies testadas (Gracilaria gracilis ou Codium tomentosum) apresentam uma germinação mais acelerada do que o controlo, traduzida por uma percentagem de germinação mais elevada, em cada dia, apresentando, ainda, um desenvolvimento superior das radículas e dos hipocótilos N, bem como uma percentagem de humidade mais elevada. Foi, ainda, possível constatar que as sementes expostas aos extratos de Gracilaria gracilis e de Codium tomentosum apresentam uma maior resistência ao stress salino e ao stress térmico. Macroalgae are widely known for being photosynthetic organisms. The species Gracilaria gracilis, as well as Codium tomentosum, are edible and present bioactive compounds of great interest, with various applications in different areas (food, cosmetics, among others). Although they are not currently widely used in agriculture, macroalgae have been used for many years as plant biostimulants. Recently, a new interest in the agricultural application of these macroalgae has emerged, related to the growing demand for products that do not harm the environment and that make plant production more profitable and sustainable. Macroalgae have in their constitution polysaccharides and plant hormones (such as auxins, cytokinin’s, ethylene, gibberellins, and abscisic acid), substances known to play a relevant role in plant development and physiology. They are also rich in protein, fiber, vitamins, and minerals. The main objective of this work was to determine the biostimulant potential of macroalgae extracts, with special emphasis on their effect on germination and plant growth. Additionally, the potential increase in resistance to heat and salt stress was tested. The biostimulant effect was tested on two agricultural species: lettuce (Lactuca sativa L.) and tomato (Solanum lycopersicum L.). It was possible to conclude that, in most trials, seeds exposed to macroalgae extracts of the species tested (Gracilaria gracilis or Codium tomentosum) show faster germination than the control, as well as a higher hypocotyl and root development and a higher moisture percentage. It was also possible to verify that the seeds exposed to extracts of Gracilaria gracilis or Codium tomentosum showed greater resistance to salt and heat stress.

Continual application of synthetic insecticides for mosquito larvae control has resulted in sever problems as build-up of mosquito resistance beside to negative impacts on human health and environment. Discovering new and affordable bio-insecticidal agents with high efficiency, cost effective and target specific become a crucial need. The current study assessed the larvicidal activity of eight methanolic algal extracts belong to three different algal divisions against the 3rd larval instar of Culex pipiens L. (Diptera: Culicidae). Comparative studies showed that four species of red and green algal extracts exhibited good larvicidal activity. Galaxaura elongata and Jania rubens (Rhodophyta), Codium tomentosum and Ulva intestinales (Chlorophyta) showed higher larvicidal potencies than Padina boryana, Dictyota dichotoma, and Sargassum dentifolium (Phaeophyta) and Gelidium latifolium (Rhodophyta). The maximum level of toxicity was achieved by exposure to G. elongata extract with LC50 (31.13 ppm), followed by C. tomentosum (69.85 ppm) then J. rubens (84.82 ppm) and U. intestinalis (97.54 ppm) while the lowest toxicity exhibited by G. latifolium (297.38 ppm) at 72h post- treatment. The application of LC50 values of G. elongate, J. rubens, C. tomentosum, and U. intestinalis extracts affected the activities of antioxidant enzymes viz. superoxide dismutase, catalase and glutathione peroxidase as oxidative stress markers. An increase of antioxidant enzymes activities was recorded. Therefore, a significant elimination of free radicals, causing toxic effects. Overall, this study casts light on the insecticidal activity of some algal extracts, suggesting the possibility of application of these bio- agents as novel and cost- effective larvicides.

Codium tomentosum is a marine green macroalga with multiple value-added applications that is being successfully used as an extractive species in sustainable integrated multi-trophic aquaculture systems. Nonetheless, growth conditions of this species at an early development phase still require optimization. The present study addresses, under controlled laboratory conditions, the effects of photoperiod (long vs. short-day) and light spectra (white, blue, and red light) on growth and pigment composition of C. tomentosum. Relative growth rate was approximately 2× higher under long-day photoperiod (average of 39.2 and 20.1% week−1 for long and short-day, respectively). Concentrations per dry weight of major pigments such as chlorophyll a (Chla) and siphonoxanthin (Siph) were significantly higher under long-day photoperiod. Relative growth rates were higher under red light, intermediate under white light, and lower under blue light. These last results were rather surprising, as Siph-Chla/Chlb light harvesting complexes of Codium have increased absorption in the blue-green region of the light spectra. Changes in carbon allocation patterns caused by the spectral composition of light and overgrowth of green microalgae in blue light cultures could explain the differences recorded for relative growth rate. Long-day photoperiod and light sources with preferential emission at the red region of the light spectra were identified as optimal for growth of C. tomentosum at early development stages. These lighting conditions can reduce the time required to reach the necessary biomass before transfer to grow-out systems. Overall, these findings can shorten production time, increase macroalgal productivity, and enhance aquaculture revenues.

The fifth basic taste—umami—is based on hydrophilic monosodium L-glutamate (L-Glu), and, to a smaller extent, on L-aspartate (L-Asp), which can be found in free form in seaweeds. The umami taste can be elicited by the synergistic effect of 5′-nucleotides, guanosine-5′-monophosphate (GMP), and inosine-5′-monophosphate (IMP). In this work, twelve edible seaweeds, two green (Codium tomentosum, Ulva rigida), six red (Chondracanthus teedei var. lusitanicus, Chondrus crispus, Gracilaria gracilis, Grateloupia turuturu, Nemalion helminthoides, Osmundea pinnatifida), and four brown (Bifurcaria bifurcata, Fucus vesiculosus, Saccorhiza polyschides, Undaria pinnatifida), from the Portuguese seashore, were selected for the analysis of umami amino acids and 5′-nucleotides. To determine the concentrations of umami free compounds, L-Glu, L-Asp, GMP, and IMP, the usual procedure for the preparation of seaweed’s broth was carried out, and the resulting extracts were analyzed by HPLC-DAD. The effect of the seaweed’s pretreatment, oven-dried and lyophilized, was also studied. Results showed that all seaweed species contained free amino acids in broad range, whereas umami 5′-nucleotides were not detected. The lyophilized C. crispus and G. gracilis contained the highest amounts of free L-Glu (627 ± 109 mg (100 g)−1 and 398 ± 67 mg (100 g)−1, respectively) and L-Asp (520 ± 102 mg (100 g)−1 and 270 ± 10 mg (100 g)−1, respectively). Two-factor PCA explained quantitatively (90%) the variance of seaweed species based on umami L-Glu content after different drying techniques applied. The results indicate that lyophilization constitutes a superior procedure for increasing the umami potential in most of the selected seaweeds.

The present study investigated the feasibility of using residual biomass of marine macroalgae (Codium tomentosum) for bioethanol production. Influence of various parameters was analyzed for optimiz...

Polysaccharides extracted from seaweeds can function as plant biostimulants. The aim of this study was to assess the effects of Polysaccharide Enriched Extracts (PEEs) obtained from 17 Moroccan seaweeds, on tomato seed germination and plant growth. Three concentrations (0.02, 0.05 and 0.1 mg mL−1) of PEEs were applied to tomato seeds to evaluate their effect on 3 germination parameters: germination percentage (GP), germination speed (GS) and mean germination time (MGT). Metabolomic analysis by GC–MS was subsequently performed on seedlings. In the second experiment, four PEEs concentrations (0.02, 0.05, 0.1 and 0.2 mg mL−1) were used as foliar spray or as soil application to tomato plants. Their growth parameters (number of leaves, shoot length, fresh and dry weight of stem and roots) and biochemical parameters (chlorophyll a and b) were measured. Results indicated a significant increase of GP and GS associated with a significant reduction of MGT of tomato seeds treated with 0.02 mg mL−1 of PEEs obtained from Gigartina sp., Gigartina pistillata, Chondracanthus acicularis, Gelidium crinale, Schizymenia dubyi, Cystoseira. foeniculacea and Fucus spiralis. Similar results were also obtained by application of higher PEEs concentration (0.1 mg mL−1) extracted from Ulva rigida, Codium tomentosum, Codium decorticatum and Bifurcaria bifurcata. Metabolomic analysis on seedlings detected the presence of some metabolites which could possibly be involved in seed germination enhancement or inhibition. The results of the second experiment showed that the same PEEs cited above at the same concentrations enhanced plant dry weight and chlorophyll a content except Gigartina sp., C. foeniculacea and C. decorticatum. Furthermore, soil application of PEEs was more effective in improving plant growth parameters than foliar application. The study shows the potential of PEEs from Moroccan seaweed to be used as biostimulants for a sustainable agriculture.

This study examined the mechanism of incorporation of the rare earth elements (REEs), La, Ce, Nd, Eu, Gd, Tb, Yb, into green (Codium tomentosum, Ulva rigida), red (Gracilaria gracilis, Osmundea pinnatifida, Porphyra sp), and brown seaweeds (Saccorhiza polyschides, Undaria pinnatifida) collected from a single site near the coastline of the Cape Mondego, western Portugal. The concentrations of REEs, Mg, Ca, Al, Fe, Zn, and Cu in the biomasses were determined by inductively-coupled plasma mass spectrometry (ICP-MS). The species showed differences in their incorporation and fractionation of REEs from the same environment: the sum of REEs was higher in U. rigida, C. tomentosum, G. gracilis, and O. pinnatifida (0.7-1.7 μg g-1) than in Porphyra sp., S. polyschides, and U. pinnatifida (0.1-0.2 μg g-1). Ratios of Ce/Yb ranged from 13 (in S. polyschides) to 103 (in U. rigida), indicating different proportions of light and heavy REEs among species. Good correlations were found between Al and Fe (R2 = 0.98), and between these elements and La, Ce, Nd, Gd (R2 = 0.88-0.97) and Yb (R2 = 0.66-0.71) for all species except C. tomentosum and G. gracilis. Profiles of REE values normalised to average upper-continental crust composition indicated positive anomalies of Eu and Tb that reinforced the singularity of these elements in the REE group. Correlations between the REEs and Al or Fe suggest that detrital terrigenous particles, adhered to seaweed walls, may be an important mechanism for the incorporation of REEs by seaweeds. Different patterns for C. tomentosum and G. gracilis may also be indicative of the higher influence of cell wall composition on REE incorporation.

Mental health and active aging are two of the main concerns in the 21st century. To search for new neuroprotective compounds, extracts of Codium tomentosum Stackhouse and Fucus vesiculosus L. were obtained through multi-step (four step) subcritical water extraction using a temperature gradient. The safety assessment of the extracts was performed by screening pharmaceutical compounds and pesticides by UHPLC-MS/MS, and iodine and arsenic levels by ICP-MS. Although the extracts were free of pharmaceutical compounds and pesticides, the presence of arsenic and high iodine contents were found in the first two extraction steps. Thus, the health-benefits were only evaluated for the fractions obtained in steps 3 and 4 from the extraction process. These fractions were tested against five brain enzymes implicated in Alzheimer’s, Parkinson’s, and major depression etiology as well as against reactive oxygen and nitrogen species, having been observed a strong enzyme inhibition and radical scavenging activities for the step 4 fractions from both seaweed species. Regarding the variation of the chemical composition during the extraction, step 1 fractions were the richest in phenolic compounds. With the increase in temperature, Maillard reaction, caramelization and thermo-oxidation occurred, and the resulting products positively affected the antioxidant capacity and the neuroprotective effects.

Aim Codium fragile, an invasive seaweed, has spread widely during the last century, impacting on local seaweed communities through competition and disturbance. Early detection of C. fragile can help on its control and management. Environmental DNA (eDNA) has proved successful for early detection of aquatic invasive species but its potential use for seaweed remains understudied. We used a species-specific eDNA qPCR approach to investigate the spatial distribution, abundance, and coexistence of the invasive C. fragile and three native Codium species (Codium vermilara, Codium tomentosum, and Codium decorticatum) in the Cantabrian Sea. Location Bay of Biscay, Northern Atlantic Coast of the Iberian Peninsula; two ports, a beach and a rocky cliff. Methods We designed species-specific primers in barcoding regions targeting short fragments of the rbcL gene for the invasive Codium species, and the elongation factor Tu (tufA) gene for the native species, to assess their spatial and seasonal distributions using quantitative real-time PCR in samples collected during summer, autumn, and winter. Results We found seasonal differences in the presence of the invasive Codium fragile and two of the native Codium species, but did not detect C. decorticatum at any point. Species distribution patterns produced with qPCR targeting species-specific eDNA coincided with the known distribution based on previous conventional sampling, with a seasonal alternance of C. fragile and C. vermilara, and a marked dominance of invasive C. fragile in ports, which are known hotspots for invasive species. Main conclusions Our results demonstrate the utility of using eDNA for early detection and monitoring of invasive seaweed. Native and invasive Codium spp. displayed significant seasonal and spatial differentiation that needs to be taken into account in risk management. Regular monitoring of ports and adjacent areas using eDNA should help to assess the potential expansion of invasive Codium and the need for management interventions to avoid the displacement of native seaweed.

Fouling is a result of the accumulation of bacterial growth, algae and sessile invertebrates on both natural and manmade submerged surface. To combat fouling ships must constantly undergo cleaning up and maintenance processes. This work aimed to evaluate new biocide antifouling paints produced from marine algae, and study their suppressive effect on slime film forming bacteria. In addition, the effect of the leached components from these wood coated surfaces containing algae on the characteristics of the contact seawater medium was investigated compared with two commercial marine paints. To evaluate the suppressive effect of algae containing coatings, extraction of the new biocide antifouling paints were done by mixing different ingredients % of binder, pigment, filler, stabilizer and solvent. The obtained paints were durable, long lasting with no cracking formed before their incorporation with algae. The paint formulations were applied to wood panels and immersed in sterile glass beakers filled with seawater medium collected from the Eastern Harbour, Alexandria, Egypt. The physicochemical parameters (temperature, salinity, pH, dissolved oxygen and nutrient salts) of seawater samples around the tested panels’ were measured after four weeks of immersion and the microbiological examination for the panels were measured after two and four weeks of immersion.Using of algae in the dry paint film leads to highest suppressive effect (%). The tested Ulva fasciata, Corallina mediterraneaand Codium Tomentosum were having the highest suppressive effect 100, 99.6 and 99.5%, respectively. These results matched with the characterization by gas chromatography-mass spectrophotometer (GC-MS) and Fourier transform infrared spectroscopy (FTIR).

This study aimed to investigate the total phenolic content (TPC), the identification of the common compounds by HPLC-ESI-MS and HPLC-ESI-MS-TOF and the inhibitory effects against class A-type β-lactamase (GES-22 variant, produced recombinantly) in methanolic extracts (MEs) of four Algerian seaweeds [Ulva intestinalis, Codium tomentosum, Dictyota dichotoma and Halopteris scoparia]. The TPC varied among the four species, ranging between 0.93 ± 0.65 and 2.66 ± 1.33 mg GAEs/g DW. C.tomentosum had higher total phenol content than other seaweeds while, all of them inhibited uncompetitively GES-22 activity in a dose-dependent manner. Nitrocefin was used as chromogenic substrate to evaluate the inhibitory effect on GES-22. The methanolic extract of D.dichotoma exhibited significant inhibitory effect on GES-22 (IC50 = 13.01 ± 0.046 μg/mL) more than clavulanate, sulbactam and tazobactam (classical β-lactam inhibitors) (IC50 = 68.38 ± 0.17 μg/mL, 52.68 ± 0.64 μg/mL, and 29.94 ± 0.01 μg/mL, respectively). IC50 of the other ME of U.intestinalis, C.tomentosum, and H.scoparia were 16.87 ± 0.10 μg/mL, 16.54 ± 0.048 μg/mL, and 25.72 ± 0.15 μg/mL, respectively. Except H. scoparia, other three seaweed extracts showed almost two times or more inhibition on GES-22. Furthermore, four common compounds in these MEs were identified, α-linolenic acid (C18:3ω3), linoleic acid (C18:2ω6), oleic acid (C18:1ω9), the eicosanoid precursors ‘‘arachidonic acid’’ (C20:4ω6). Baicalein (C15H10O5) was identified in U.intestinalis and D.dichotoma seaweeds. The fact that all seaweed extracts inhibited the GES-22 better than commercial samples makes these seaweeds candidate for discovering new inhibitors against β-lactamases. Besides that, they contain important components with potential health benefits.

This work was supported by the Portuguese Foundation for Science and Technology (FCT) through the strategic project UID/04292/2020 granted to MARE—Marine and Environmental Sciences Centre, and UIDP/04046/2020 and UIDB/04046/2020 granted to BioISI—BioSystems and Integrative Sciences Institute, through POINT4PAC project (Oncologia de Precisão: Terapias e Tecnologias Inovadoras, SAICTPAC/0019/2015-LISBOA- 01-0145-FEDER-016405), through CROSS-ATLANTIC project (PTDC/BIA-OUT/29250/2017), co-financed by COMPETE (POCI-01-0145-FEDER-029250) and through Molecules for Health project (PTDC/BIA-BQM/28355/2017). This work was also funded by the Integrated Programme of SR&TD Smart Valorization of Endogenous Marine Biological Resources Under a Changing Climate (Centro-01-0145-FEDER-000018), co-funded by Centro 2020 Programme, Portugal 2020, European Union, through the European Regional Development Fund. Parkinsons Disease (PD) is the second most common neurodegenerative disease worldwide, and is characterized by a progressive degeneration of dopaminergic neurons. Without an effective treatment, it is crucial to find new therapeutic options to fight the neurodegenerative process, which may arise from marine resources. Accordingly, the goal of the present work was to evaluate the ability of the monoterpenoid lactone Loliolide, isolated from the green seaweed Codium tomentosum, to prevent neurological cell death mediated by the neurotoxin 6-hydroxydopamine (6-OHDA) on SH-SY5Y cells and their anti-inflammatory effects in RAW264.7 macrophages. Loliolide was obtained from the diethyl ether extract, purified through column chromatography and identified by NMR spectroscopy. The neuroprotective effects were evaluated by the MTT method. Cells’ exposure to 6-OHDA in the presence of Loliolide led to an increase of cells’ viability in 40%, and this effect was mediated by mitochondrial protection, reduction of oxidative stress condition and apoptosis, and inhibition of the NF-KB pathway. Additionally, Loliolide also suppressed nitric oxide production and inhibited the production of TNF- and IL-6 pro-inflammatory cytokines. The results suggest that Loliolide can inspire the development of new neuroprotective therapeutic agents and thus, more detailed studies should be considered to validate its pharmacological potential. info:eu-repo/semantics/publishedVersion

[Resumen]: En este trabajo se realizó un estudio comparativo del proceso de adsorción del catión Zn+2 mediante el uso de tres algas distintas: Fucus vesiculosus (alga parda), Mastocarpus stellatus (alga roja) y Codium tomentosum (alga verde). Se evaluó la influencia del pH con el fin de conocer el rango adecuado en el cual llevar a cabo la adsorción. Los resultados obtenidos evidenciaron que los más idóneos para las distintas algas son: entre 5 y 7 para el alga parda, entre 6 y 7 para el alga roja y entre 4 y 7 para el alga verde. En lo referente a los estudios cinéticos, se observó que las tres algas alcanzaron el equilibrio de adsorción en tiempos relativamente cortos: para el alga verde y alga roja el equilibrio se alcanzó a los 25 min, mientras que, para el alga parda, a los 40 min. Por otra parte, para la misma concentración inicial de Zn+2 (125 mg/L), tanto el alga roja como el alga parda, eliminaron una mayor cantidad de adsorbato del medio, en torno al 50%, mientras que el alga verde solo consiguió eliminar un 20% de Zn+2. Finalmente, se realizaron estudios de adsorción a tres temperaturas distintas (25 ºC, 35 ºC y 50 ºC) y, mediante representación gráfica de isotermas de Langmuir, se observó una influencia de la temperatura en el caso del alga Mastocarpus stellatus, mientras que para las algas Fucus vesiculosus y Codium tomentosum, tanto las gráficas como los valores de qmax y Kads no difirieron con la variación de temperatura. [Resumo]: Neste traballo realizouse un estudo comparativo do proceso de adsorción do catión Zn+2 mediante o uso de tres algas distintas: Fucus vesiculosus (alga parda), Mastocarpus stellatus (alga vermella) y Codium tomentosum (alga verde). Avaliouse a influencia do pH co fin de coñecer o rango adecuado no cal levar a cabo a adsorción. Os resultados obtidos evidenciaron que os máis idóneos para as distintas algas son: entre 5 e 7 para a alga parda, entre 6 e 7 para a alga vermella e entre 4 e 7 para a alga verde. No referente aos estudos cinéticos observouse que as tres algas alcanzan o equilibrio de adsorción en tempos relativamente cortos: para a alga verde e a alga vermella alcanzouse o equilibrio ós 25 min, mentres que para a alga parda, ós 40 min. Por outra parte, para a mesma concentración inicial de Zn+2 (125 mg/L), tanto a alga vermella como a alga parda, eliminaron unha maior cantidade de adsorbato do medio, en torno ó 50%, mentres que a alga verde so conseguiu eliminar un 20% de Zn+2. Finalmente, realizáronse estudos de adsorción a tres temperaturas distintas (25 ºC, 35 ºC e 50 ºC) e, mediante representación gráfica das isotermas de Langmuir, observouse a influenza da temperatura no caso da alga Mastocarpus stellatus, mentres que para as algas Fucus vesiculosus e Codium tomentosum tanto as gráficas como os valores de qmax e Kads non diferiron ca variación da temperatura. [Abstract]: In this work, a comparative study of the Zn+2 cation adsorption process was carried out using three different algae: Fucus vesiculosus (brown alga), Mastocarpus stellatus (red alga) and Codium tomentosum (green alga). The influence of pH was evaluated in order to determine the appropriate range in which to carry out adsorption. The results obtained showed that the most suitable for the different algae are: between 5 and 7 for the brown alga, between 6 and 7 for the red alga and between 4 and 7 for the green alga. Regarding the kinetic studies, it was observed that the three algae reached the adsorption equilibrium in relatively short times: for the green and red algae the equilibrium was reached after 25 min, while for the brown alga 40 min were required. On the other hand, for the same initial concentration of Zn+2 (125 mg/L), both the red and brown algae eliminated a larger amount of adsorbate from the medium, around 50%, while the green alga only attained 20% of Zn+2 elimination. Finally, adsorption studies were carried out at three different temperatures (25º C, 35º C and 50º C) and, using Langmuir isotherm graphs, an influence of temperature was observed in the case of the alga Mastocarpus stellatus, while for the algae Fucus vesiculosus and Codium tomentosum, both the graphs and the values of qmax and Kads did not change with temperature. Traballo fin de grao (UDC.CIE). Química. Curso 2020/2021

The abundance and distribution of intertidal canopy-forming macroalgae are threatened by the increase in sea surface temperature and in the frequency and intensity of heatwaves caused by global warming. This study evaluated the physiological response of predominant intertidal macroalgae in the NW Iberian Peninsula (Bifurcaria bifurcata, Cystoseira tamariscifolia and Codium tomentosum) to increased seawater temperature during immersion and increased air temperatures during consecutive emersion cycles. We combined field mensuration and laboratory experiments in which we measured mortality, growth, maximum quantum yield and C:N content of the macroalgae. Air temperature was a critical factor in determining physiological responses and survivorship of all species, whereas high seawater temperature had sublethal effects. Cystoseira tamariscifolia suffered the greatest decreases in Fv/Fm, growth and the highest mortality under higher air temperatures, whereas C. tomentosum was the most resistant and resilient species. Two consecutive cycles of emersion under atmospheric heatwaves caused cumulative stress in all three macroalgae, affecting the physiological performance and increasing the mortality. The potential expansion of the warm-temperate species B. bifurcata, C. tamariscifolia and C. tomentosum in the NW Iberian Peninsula in response to increasing seawater temperature may be affected by the impact of increased air temperature, especially in a region where the incidence of atmospheric heatwaves is expected to increase.

Marine edible macroalgae have functional proprieties that might improve human health and wellbeing. Lipids represent a minor fraction of macroalgae, yet with major interest as main carriers of omega 3 polyunsaturated fatty acids and intrinsic bioactive properties. In this study, we used lipid extracts from the green macroalgae Ulva rigida and Codium tomentosum, the red Gracilaria gracilis,Palmaria palmata and Porphyra dioica, and the brown Fucus vesiculosus, produced in a land-based integrated multitrophic aquaculture (IMTA) system. We determined the lipid quality indices based on their fatty acid profiles and their bioactivities as putative antioxidant, anti-inflammatory and antiproliferative agents. The results reveal to be species-specific, namely U. rigida displayed the lowest atherogenicity and thrombogenicity indices. Palmaria palmata and F. vesiculosus lipid extracts displayed the lowest inhibitory concentration in the free radical scavenging antioxidant assays. Ulva rigida, C. tomentosum, P. palmata and P. dioica inhibited COX-2 activity by up to 80%, while P. dioica and P. palmata extracts showed the highest cytotoxic potential in the MDA-MB-231 breast cancer cells. This work enhances the valorization of macroalgae as functional foods and promising ingredients for sustainable and healthy diets and fosters new applications of high-valued algal biomass, in a species-specific context.

Several species of sacoglossan sea slugs are able to sequester chloroplasts from algae and incorporate them into their cells. However, the ability to maintain functional “stolen” plastids (kleptoplasts) can vary significantly within the Sacoglossa, giving species different capacities to withstand periods of food shortage. The present study provides an insight on the comparative shifts experienced by the lipidome of two sacoglossan sea slug species, Elysia viridis (long-term retention of functional chloroplasts) and Placida dendritica (retention of non-functional chloroplasts). A hydrophilic interaction liquid chromatography–mass spectrometry approach was employed to screen the lipidome of specimens from both species feeding on the macroalga Codium tomentosum and after 1-week of starvation. The lipidome of E. viridis was generally unaffected by the absence of food, while that of P. dendritica varied significantly. The retention of functional chloroplasts by E. viridis cells allows this species to endure periods of food shortage, while in P. dendritica a significant reduction in the amount of main lipids was the consequence of the consumption of its own mass to endure starvation. The large proportion of ether phospholipids (plasmalogens) in both sea slug species suggests that these compounds may play a key role in chloroplast incorporation in sea slug cells and/or be involved in the reduction of the oxidative stress resulting from the presence of kleptoplasts.

In the last decades, the use of algae in biotechnology and food industries has experienced an exponential growth. Codium tomentosum is a green macroalgae with high biotechnological potential, due to its rich lipidome, although few studies have addressed it. This study aimed to investigate the seasonal changes in lipid and pigment profiles of C. tomentosum, as well as to screen its antioxidant activity, in order to evaluate its natural plasticity. Samples of C. tomentosum were collected in two different seasons, early-autumn (September/October) and spring (May), in the Portuguese coast (wild samples), and in a land-based integrated multitrophic aquaculture (IMTA) system (IMTA samples). Total lipid extracts were analysed by LC&ndash, MS, GC&ndash, MS, and HPLC, and antioxidant activity was screened through free radical scavenging potential against DPPH and 2,20-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radicals. Wild samples showed a high seasonal variability, modifying their lipidome and pigment profiles according to environmental shifts, while IMTA samples showed a relatively stable composition due to early-stage culturing in controlled conditions. The lipids that contributed the most to seasonal discrimination were glycolipids (monogalactosyl diacylglycerol - MGDG and digalactosyl diacylglycerol - DGDG) and the lyso forms of phospholipids and glycolipids. Lipid extracts showed antioxidant activity ranging from 61 &plusmn, 2 to 115 &plusmn, 35 &micro, mol Trolox g&minus, 1 of lipid extract in DPPH assay and from 532 &plusmn, 73 to 927 &plusmn, 92 &micro, 1 of lipid extract in ABTS assay, with a more intense antioxidant activity in wild spring samples. This study revealed that wild specimens of C. tomentosum presented a higher plasticity to cope with seasonal environmental changes, adjusting their lipid, pigment, and bioactivity profiles, while IMTA samples, cultured under controlled conditions, displayed more stable lipidome and pigment compositions.

Trabalho final de mestrado para obtenção do grau de Mestre em Engenharia Química e Biológica Submitted by Sónia Mestre (sonia.mestre@isel.pt) on 2021-05-11T17:20:17Z No. of bitstreams: 1 Dissertação_2187.pdf: 1652223 bytes, checksum: f37a4413b022a395b199138622a3cf52 (MD5) Made available in DSpace on 2021-05-11T17:20:17Z (GMT). No. of bitstreams: 1 Dissertação_2187.pdf: 1652223 bytes, checksum: f37a4413b022a395b199138622a3cf52 (MD5) Previous issue date: 2020-01-07 N/A

Mestrado em Engenharia Alimentar / Instituto Superior de Agronomia. Universidade de Lisboa O presente estudo pretendeu avaliar a estabilidade oxidativa de óleo de girassol suplementado com macroalgas Codium tomentosum e Pelvetia canaliculata, comparativamente a amostras controlo (óleo de girassol não suplementado). Os extratos foram obtidos por extração direta no óleo com recurso a ultrassons e por tratamento enzimático com a preparação comercial Ultimase BWL 40. A eficiência do tratamento enzimático foi avaliada através da quantificação dos açúcares solúveis segundo o método colorimétrico de Fenol-Sulfúrico. A capacidade antioxidante dos óleos suplementados foi determinada por quantificação dos compostos fenólicos totais (CFT) pelo método de Folin-Ciocalteu, da avaliação da atividade de redução do radical DPPH e da avaliação do poder de redução férrica (FRAP). A estabilidade oxidativa foi avaliada em condições de oxidação acelerada em Rancimat e através da análise dos produtos de oxidação por Espectrofotometria no UV/Vis. Determinaram-se as características cromáticas dos óleos suplementados, tendo-se observado um aumento na intensidade da coloração amarelo com o aumento da concentração de alga e nas amostras suplementadas com P. canaliculata. O teor em carotenóides apresentou valores superiores nos óleos suplementados com P. canaliculata e nos óleos com maior concentração de alga. A amostra de óleo suplementado com 15% (m/v) de Pelvetia canaliculata e sujeito a 15 min de ultrassons (P’ 15%) apresentou maior atividade antioxidante, com 21,2 ± 4,2 μg equivalentes de ácido gálico/g de extrato, 17,6 ± 3,5 μM de FeSO4/g de extrato e 29,8 ± 3,8 % de Atividade de Redução do Radical DPPH. Conclui-se que o tratamento por ultrassons foi, de uma forma geral, mais eficaz na produção de extratos com atividade antioxidante do que o tratamento enzimático, para os óleos suplementados com P. canaliculata. Por outro lado, verificou-se que os óleos obtidos por incorporação da alga C. tomentosum não apresentaram diferenças significativas em relação ao aumento da atividade antioxidante dos mesmos N/A

Funding This work was supported by the Portuguese Foundation for Science and Technology (FCT) through strategic project UID/MAR/04292/2020 granted to MARE—Marine and Environmental Sciences Centre, through Red2Discovery project (PTDC/MAR-BIO/6149/2014), co-fnanced by COMPETE (POCI-01-0145-FEDER-016791), through Oncologia de Precisão: Terapias e Tecnologias Inovadoras project (POINT4PAC) (SAICTPAC/0019/2015-LISBOA-01-0145-FEDER-016405) and through CrossAtlantic project (PTDC/BIA-OUT/29250/2017), co-fnanced by COMPETE (POCI-01-0145-FEDER-029250). This work was also funded by the Integrated Programme of SR&TD Smart Valorization of Endogenous Marine Biological Resources Under a Changing Climate (reference Centro-01-0145-FEDER-000018), co-funded by Centro 2020 Programme, Portugal 2020, European Union, through the European Regional Development Fund. FCT is also acknowledged for the grant attributed to J.S. (SFRH/BD/103255/2014). Neurodegenerative diseases, such as Parkinson’s disease, represent a biggest challenge for medicine, imposing high social and economic impacts. As a result, it is of utmost importance to develop new therapeutic strategies. The present work evaluated the neuroprotective potential of seaweeds extracts on an in vitro dopamine (DA)-induced neurotoxicity cellular model. The neuroprotective effects on SH-SY5Y cells’ viability were estimated by the MTT assay. Changes in mitochondrial membrane potential (MMP), caspase-3 activity, and hydrogen peroxide (H2O2) production were determined. DA (30–3000 μM; 24 h) treatment decreased SH-SY5Y cells’ viability in concentration and time-dependent manner, increasing the H2O2 production, MMP depolarization, and caspase-3 activity. On the other hand, DA (1000 μM; 24 h) toxicity was reduced (10–15%) with Sargassum muticum and Codium tomentosum extracts (1000 μg/mL; 24 h). The highest neuroprotective activity was exhibited by a methanolic extract obtained from Saccorhiza polyschides, which completely blunted DA effects. Results show that the marine seaweed S. polyschides contain substances with high neuroprotective potential against the toxicity induced by DA, exhibiting anti-apoptotic effects associated with both mitochondrial protection and caspase-3 inhibition. S. polyschides reveals, therefore, to be an excellent source of bioactive molecules, for new drugs development aiming PD therapeutics. info:eu-repo/semantics/publishedVersion

WOS:000492408400001; Codium tomentosum, as all organisms, hosts transiently and permanently numerous microorganisms. These holobionts can undergo environmental pressures influencing both partners creating modifications/imbalances within the associations, which may directly influence their physiological status by selecting tolerant bacteria. Furthermore, the capability of remediation of the associated bacterioflora, in particular of metallic trace elements, may provide the host with survival potential in polluted environments. In this context, we incubated C. tomentosum thalli in the presence of copper and studied its influence on the reference bacteriome. Whatever the concentration of copper, no shift was evidenced on the bacteriome at the phylum level. However, a high copper concentration enriched the bacteriome of C. tomentosum in both the genera Clostridium and Pseudolteromonas.

Codium tomentosum seaweed structured Bi2O3 was prepared by anodization technique using thermally evaporated bismuth films. The present study concerns the development of an efficient CO2 sensor at room temperature by controlling the crystallinity, morphology, carrier concentration, and bang gap. Crystal structure variation was achieved by sequential annealing from 200 to 600 °C. During anodization, truncated polyhedral aggregates of bismuth particles get reformed into Codium tomentosum seaweed like nanostructures of Bi2O3. The nature of Bi2O3 semiconductor with carrier concentration has been identified from the Mott–Schottky plot. Lattice defects such as oxygen vacancies, Bi interstitials, recombination effect, and band gap values were analyzed through optical studies. The sensor study was performed at room temperature for the detection of CO2 gas in the concentration 10–100 ppm. Bi2O3 nanostructure annealed at 400 °C having amorphous nature offered the maximum response magnitude. The underlying, sensing mechanism was correlated with the experimental findings on the basis of optical properties and surface morphology.

In the past decade, algal waste has been used as useful natural resource for production of enormous range of products that have wide economical and commercial importance. Pectinases are group of enzymes that have wide commercial applications. Hence, current study was designed to utilize algal biomass for the production of pectinases using submerged (SmF) and solid state fermentation (SSF) techniques. Different algal sources including brown (Dictyopteris polypodioides, Sargassum wightii and Dictyopteris divaricata) and green algae (Ulva lactuca and Codium tomentosum) were used and U. lactuca was found to be the most suitable substrate. Several bacterial and fungal strains were screened and among them Bacillus licheniformis KIBGE-IB4 was selected based on maximum pectinase production. SmF and SSF were studied utilizing U. lactuca as a substrate and results revealed that enzyme production was favoured by SmF (2457 ± 3.31 U mg−1) as compared to SSF (1432 ± 1.46 U mg−1). Parametric optimization of pect...