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  • Different seaweeds use for iodine deficiency overcome
    Publication . Ferraz, Sónia; Ragonezi, Carla; Nunes, Nuno; Valente, Sofia; Carvalho, Miguel A. A. Pinheiro de
    Iodine deficiency is one of the three most common nutritional deficiencies worldwide and is a global public health problem that affects particularly the young children, pregnant women and elderly. The consequences of iodine deficiency disorder (IDD) include goiter and cretinism. The traditional consumption of iodine via supplemented salt should be monitored to reduce population sodium intake due to hypertension problems and the uncertain bioavailability of iodine in the supplemented salt. One approach for an effective and cost-efficient iodine supplementation is the use of seaweeds in food intake. Seaweeds, among all foods, are the most famous and reliable source of natural iodine. In this minireview we pretend to explore the different uses of seaweeds to fill the iodine deficiency and improve life quality.
  • Nutraceutical potential of Asparagopsis taxiformis (Delile) Trevisan extracts and assessment of a downstream purification strategy
    Publication . Nunes, Nuno; Valente, S.; Ferraz, Sónia; Barreto, Maria Carmo; Carvalho, M .A. A. Pinheiro de
    The main goal of the present work was to determine the nutraceutical potential of Asparagopsis taxiformis D. extracts from Madeira Archipelago south coast. Extraction methodologies consisted either/or in 72 hours stirring, at room temperature (M1), or 6 cycles of Soxhlet extraction (M2), both with re-extraction. Solvents used were distilled water, ethanol, methanol and ethyl acetate. M1 allowed to obtain the highest values for extraction yield (31.65 g.100g 1 dw) using water, whereas iodine content (3.37 g.100g 1 dw), TPC (1.71 g GAE.100g 1 dw) and chlorophyll a (45.96 mg.100g 1 dw) were obtained using ethanol, and TCC (36.23 mg.100g 1 dw) with methanol. Extracts that showed higher reduction activity in M1 were derived from ethanol extraction (1,908 mg AAE.100g 1 dw). Water and ethanol were the best solvents for higher DPPH scavenging activity in M2, both with same result (IC50 1.37 mg.mL 1 ). The lowest value of IC50 for chelating activity (1.57 mg.mL 1 ) was determined in M1, using ethyl acetate. The remaining residue was used to obtain other products, i.e. lipid extraction (M1, 2.05 g.100g 1 dw), carrageenans (M2, 21.18 g.100g 1 dw) and cellulose (M1, 23.81 g.100g 1 dw) with subsequent FTIR ATR analysis. Our results show that A. taxiformis is a valuable source of bioactive compounds. The M1 extraction methodology using ethanol is the most effective solvent to produce an iodine rich bioactive extract with potential of being used as a nutraceutical supplement. Also, we have demonstrated a possible downstream strategy that could be implemented for multiple compound extraction from A. taxiformis residue. This has a vital importance for future feasibility, when using this biomass as an industrial feedstock for multiple products production. Statistical analysis, using SPSS 24.0, was also performed and important correlations were found between assays and methods.
  • Pharmacological and cosmeceutical potential of Seaweed Beach-Casts of Macaronesia
    Publication . Zárate, Rafael; Portillo, Eduardo; Teixidó, Sílvia; Carvalho, Miguel A. A. Pinheiro de; Nunes, Nuno; Ferraz, Sónia; Seca, Ana M. L.; Rosa, Gonçalo P.; Barreto, Maria Carmo
    Seaweed beach-casts are a seasonal phenomenon that regularly deposits tons of algae biomass on beaches, which are usually disposed of in landfills. The present work aimed to contribute to the valorization of this biomass by studying bioactivities that reveal its potential in the pharmaceutical and/or cosmeceutical industries. Methanol and ethanol extracts and fractions from 15 beach-casts biomass were tested for a range of bioactivities. Eight of the most active samples exhibit IC50 values between 11.38 µg/mL and 19.28 µg/mL and selectivity indexes higher than 3.8, against NCI-H1299 (lung cancer) and T47D (breast cancer). Concerning antiaging potential, all the extracts tested presented UV protection, with SPF values above 30, like the standard sunscreen. Regarding aging-related enzymes, 24 samples were tyrosinase inhibitors exhibiting IC50 values from 9.01 µg/mL to 200.09 µg/mL. Eight extracts inhibited collagenase (IC50 < 248.76 µg/mL), two of them more actively than positive control EDTA (IC50 = 59.26 µg/mL). In addition to UV protection, the cumulative effect of antityrosinase and anticollagenase activities shown by the samples suggest that they may play a significant role in preventing skin photoaging. The results obtained demonstrate the high potential of beach-cast seaweed biomass as sources of cosmetic bioproducts with antiaging effects, and of selective cytotoxic metabolites.
  • From a heavy metal perspective, is macroalgal biomass from Madeira Archipelago and Gran Canaria Island of eastern Atlantic safe for the development of blue bioeconomy products?
    Publication . Nunes, Nuno; Ferraz, Sónia; Venuleo, Marianna; Barros, Ana I. R. N. A.; Carvalho, Miguel A. A. Pinheiro de
    Macroalgae are considered a valuable source of several compounds with nutritional, nutraceutical, cosmeceutical, and phar maceutical applications. They are also used for crop fertilization and biofortifcation by introducing important minerals into the soil essential for crop productivity. At the same time, however, they are known bio-accumulators of some heavy metals. In this work, we assessed the content of 7 minerals considered as heavy metals in 25 macroalgae samples, comprising 4 greens, 9 reds and 12 browns, from Madeira Archipelago, Portugal, for their potential use as blue bioeconomy products. These heavy metals included zinc (Zn) with concentrations that ranged from 1.95 – 242.65 mg kg−1 dw, nickel (Ni, 0.6 – 34.78 mg kg−1 dw), copper (Cu, 0.42 – 7.98 mg kg−1 dw), chromium (Cr, 0.47 – 45.74 mg kg−1 dw), cadmium (Cd, 0.1 – 2.58 mg kg−1 dw), lead (Pb, 0.05 – 2.79 mg kg−1 dw) and mercury (Hg, 0.03 – 8.49 µg kg−1 dw). We also analysed 22 samples of beach-cast macroalgae from Gran Canaria Island, Spain, collected from November 2016 to November 2019. The same heavy metals were assessed with their concentrations that ranged as follows: Zn (11.41 – 42.20 mg kg−1 dw), Ni (3.17 – 17.78 mg kg−1 dw), Cu (1.85 – 4.20 mg kg−1 dw), Cr (6.08 – 37.98 mg kg−1 dw), Cd (0.02 – 0.11 g kg−1 dw), Pb (0.16 –5.42 mg kg−1 dw) and Hg (3.59 – 31.00 µg kg−1 dw). These concentrations are all within the normal ranges reported in earlier studies in low industrialized areas, except for the brown algae Gongolaria abies-marina and Sargassum vulgare with high mean (±SD) Cd concentration (1.91±0.36 and 1.75±0.07 g kg−1 dw respectively). Our results suggest that most of the biomass prospected in these localities covered in the present study would be a viable source of materials for the development of a blue economy industry with emerging products following the European Union directives.
  • Biochemical study of attached macroalgae from the Madeira Archipelago and beach-cast macroalgae from the Canary Islands: multivariate analysis to determine bioresource potential
    Publication . Nunes, Nuno; Valente, Sofia; Ferraz, Sónia; Barreto, Maria Carmo; Carvalho, Miguel Â. A. Pinheiro de
    Fifteen attached macroalgae from the Madeira Archipelago, comprising three green, three red and nine brown algal species, as well as two beach-cast macroalgal samples, collected along the north shore of Gran Canaria, were assessed for their biochemical properties. The anal ysis included the determination of total minerals, total carbohydrates, protein, lipids, chlorophyll a, total carote noids, total phenolic content, fucoxanthin and phycobilins (allophycocyanin, phycocyanin and phycoerythrin). The results showed a high variability of biochemical composi tion, allowing for the targetting of specific bioresources for particular purposes, including functional foods. This work provides the foundation for a biorefinery strategy implementation plan, for which specific macroalgae may be tar geted for valuable and beneficial compounds