Browsing by Author "Carvalho, Miguel A. A. Pinheiro de"
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- Biochemical study of attached macroalgae from the Madeira Archipelago and beach-cast macroalgae from the Canary Islands: multivariate analysis to determine bioresource potentialPublication . Nunes, Nuno; Valente, Sofia; Ferraz, Sónia; Barreto, Maria do Carmo; Carvalho, Miguel A. A. Pinheiro deFifteen 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 analysis included the determination of total minerals, total carbohydrates, protein, lipids, chlorophyll a, total carotenoids, total phenolic content, fucoxanthin and phycobilins (allophycocyanin, phycocyanin and phycoerythrin). The results showed a high variability of biochemical composition, 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 targeted for valuable and beneficial compounds.
- Constructing ethanol-derived bioactive extracts using the brown seaweed Zonaria tournefortii (J.V.Lamouroux) Montagne performed with Timatic extractor by means of response surface methodology (RSM)Publication . Nunes, Nuno; Valente, Sofia; Ferraz, Sónia; Barreto, Maria do Carmo; Carvalho, Miguel A. A. Pinheiro deUnderstanding the biochemical and antioxidant composition and capacity of a target biomass is the first step to its selectivity as functional food which can enhance the ability to promote health by reducing the risk of chronic diseases. The main purpose of this work was to employ response surface methodology (RSM) to determine the effect of the independent variables, % of ethanol (50–96%), time of sonication (0–20 min), and number of extraction cycles (6–18 cycles) in the primary extract of brown seaweed Zonaria tournefortii, studying the yield variation of some bioactive compounds, assessing the potential of these bioextracts to integrate as a natural additives or supplements in the functional food industry. The extractions were performed employing “Green Chemistry” techniques executed with the Timatic extractor, which applied pressurized ethanol solution at a maximum pressure of 8.5 bar through milled dehydrated biomass in the extraction vessel. Several parameters were assessed in the primary bioactive extract which included extract yield (11.56–28.49 g (100 g)⁻¹ dw), total chlorophyll content (0.14–1.42 g (100 g)⁻¹ dw), total carotenoid content (0.35–0.80 g (100 g)⁻¹ dw), total fucoxanthin content (0.04–0.13 g (100 g)⁻¹ dw), total phenolic content (3.58–5.84 g (100 g)⁻¹ dw), total flavonoid content (0.22–4.70 g (100 g)⁻¹ dw), DPPH (56.05–76.45%), and reducing activity (3.83–6.04 g (100 g)⁻¹ dw). A second objective was to determine the suitability of the residue for subsequent extraction of valuable compounds such as fucoidan (4.87 to 6.59 g (100 g)⁻¹ dw) and cellulose (18.88 to 20.27 g (100 g)⁻¹ dw), implementing the first step to a biorefinery strategy, using a cascade approach.
- Fatty acid composition, TLC screening, ATR-FTIR analysis, anti-cholinesterase activity, and in vitro cytotoxicity to A549 tumor cell line of extracts of 3 macroalgae collected in MadeiraPublication . Nunes, Nuno; Rosa, Gonçalo P.; Ferraz, Sónia; Barreto, Maria do Carmo; Carvalho, Miguel A. A. Pinheiro deThree macroalgae collected at Madeira Island were included in this study to determine their potential for drug, nutraceutical, food, or supplement application. Fatty acid content was higher in Zonaria tournefortii (12.32 mg g⁻¹ dw) with 16.58% of PUFAs, eicosapentaenoic acid (C20:5 omega 3), and arachidonic acid (20:4 omega 6) having concentrations of 2.59 and 1.17%, respectively. The anti-thrombogenic and anti-atherogenicity potential was higher for Z. tournefortii due to relevant fatty acids in the biochemical composition this macroalgae. Lipid classes were assessed in the lipid extract and neutral lipids (NL) were in higher yield in Asparagopsis taxiformis (51.16%) and lower in Z. tournefortii (26.96%). The glycolipids (GL) were between 36.03 and 16.11% in Z. tournefortii and Ulva lactuca. Phospholipids (PL) fraction varied from 35.91 and 31.60% in A. taxiformis and Z. tournefortii. TLC screening identified that U. lactuca contains phytol and cholesterol in its NL, digalactosyldiacylglycerol in its GL, and cardiolipin and L-alpha-phosphatidylcholine in its PL. Zonaria tournefortii contains phytol and cholesterol in its NL classes, and the PL classes contain L-alpha-phosphatidylethanolamine and 1-(3-sn-phosphatidyl)-rac-glycerol. The macroalgae A. taxiformis revealed cholesterol in its NL fraction and the same phospholipids as Z. tournefortii in its PL fraction. ATR-FTIR analysis enabled a "fingerprint" spectra and important sulfation absorption bands were identified, revealing the functional polysaccharides within these macroalgae. Anti-cholinesterasic activity was assessed in A. taxiformis, with a low IC50 for AChE (8.92 +/- 0.43 mu g mL⁻¹) and BuChE (13.96 +/- 0.32 mu g mL⁻¹), demonstrating dual inhibitory activity, justifying the interest to identify the active principle which may be the scaffold of a novel drug.
- Marine macroalgae for industrial extraction of valuable biofunctional compounds using biorefinery. Algal Metabolites: Biotechnological, Commercial and Industrial ApplicationsPublication . Nunes, Nuno; Barreto, Maria do Carmo; Carvalho, Miguel A. A. Pinheiro deAlgal secondary metabolites have several biotechnological, pharmaeceutical, industral, cosmetic, and other commercial applications. This new book highlights the recent advances in algal active metabolites, emphasizing their pharmaceutical, therapeutic, nutraceutical, and industral potential. It first provides an introduction to algal metabolites and discusses their applications. It then looks at microalgal- their pharmaeceutical, therapeutic, nutraceutical, and industrial applications. Providing a wealth of information, this book illustrates the diversity of these metabolites from indegeneous marine of freshwater sources, providing a gateway that can enable researchers and pharmaceutical companies to develop novel nontoxic, cost-effective, and highly efficient drugs.
- Pharmacological and Cosmeceutical Potential of Seaweed Beach-Casts of MacaronesiaPublication . 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 do CarmoSeaweed 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.