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In recent years, research on the bioactive properties of macroalgae has increased, due to the great interest in exploring new products that can contribute to improve human health and wellbeing. In the present study, the antioxidant and antimicrobial potential of six different brown algae of the Fucales order were evaluated, namely Ericaria selaginoides, Ericaria amentacea, Gongolaria baccata, Gongolaria usneoides, Cystoseira compressa and Sargassum vulgare (collected along the Mediterranean and Atlantic coasts). The antioxidant capacity was measured by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, the oxygen radical absorbent capacity (ORAC) and the ferric reducing antioxidant power (FRAP) and were related to the total phenolic content (TPC). The antimicrobial activity was evaluated measuring the growth inhibition of Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans.The highest antioxidant capacity was obtained for Ericaria selaginoides revealing the highest capacity to scavenge DPPH radical [half maximal effective concentration (ECAmong all studied seaweed, Ericaria selaginoides reveals the highest antioxidant and antimicrobial activities, and thus should be explored as a natural food additive and/or functional ingredient. © 2022 Society of Chemical Industry.

ACKNOWLEDGMENTS : The team would like to acknowledge Campotec S.A for the opportunity to produce industrial samples in its installations. The authors acknowledge the support of Fundação para a Ciência e Tecnologia (FCT), through the strategic projects UIDB/04292/2020 and UIDP/04292/2020 granted to MARE, and the grants awarded to Ana Augusto (SFRH/BD/131465/2017) and Andreia Miranda (SFRH\BD\145425\2019). The authors acknowledge the support of the project Alagecoat (POCI-01-0247-FEDER-006392) through the COMPETE-Operational Competitiveness Programme, the European Union through EASME Blue Labs project AMALIA, Algaeto-MArket Lab IdeAs (EASME/EMFF/2016/1.2.1.4/03/SI2.750419), and the ORCHESTRA project (number 70155), co-funded by Centro 2020 program, Portugal 2020, European Union, European Regional Development Fund. Codium tomentosum hydroethanolic extract was obtained using a pilot solid–liquid extractor to validate the anti-browning functionality of the extract under industrial conditions. Fresh-cut apple slices were coated by immersion in: (1) a seaweed extract solution (0.5% w/v) and (2) a commercial coating, and the two sets of samples were compared with a control (immersion in water). Packaged samples were stored, under ambient and modified atmosphere conditions at 4°C. After 30 days of storage, the samples that were coated with the seaweed extract and packaged under modified atmosphere, demonstrated lower peroxidase activity and polyphenol oxidation when compared with the samples treated with the commercial additive. These results confirm, at pilot scale and under industrial production conditions, the efficacy of the seaweed extract as a bio-based substitute for the synthetic coatings, which are currently used to prevent browning in fresh-cut apples. Novelty impact statement Fresh-cut fruits are subjected to processing operations leading to a decrease in nutritional and organoleptic properties. It is therefore necessary to adopt strategies to delay the degradative processes. In this study, the efficacy of a pilot-scale production and industrial application of a coating formulated with Codium tomentosum seaweed extract has been established for the first time. This seaweed extract possesses the potential to prevent browning development in fresh-cut apples under industrial operating conditions. info:eu-repo/semantics/publishedVersion

Macroalgae‐associated bacteria have already proved to be an interesting source of compounds with therapeutic potential. Accordingly, the main aim of this study was to characterize Asparagopsis armata‐associated bacteria community and evaluate their capacity to produce substances with antitumor and antimicrobial potential. Bacteria were selected according to their phenotype and isolated by the streak plate technique. The identification was carried out by the RNA ribosomal 16s gene amplification through PCR techniques. The antimicrobial activities were evaluated against seven microorganisms (Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Salmonella enteritidis, Staphylococcus aureus, Saccharomyces cerevisiae, Candida albicans) by following their growth through spectrophotometric readings. Antitumor activities were evaluated in vitro on human cell lines derived from hepatocellular (HepG‐2) and breast carcinoma (MCF‐7) using the MTT method. The present work identified a total of 21 bacteria belonging to the genus Vibrio, Staphylococcus, Shewanella, Alteromonadaceae, Bacillus, Cobetia, and Photobacterium, with Vibrio being the most abundant (42.86%). The extract of Shewanella sp. ASP 26 bacterial strain induced the highest antimicrobial activity, namely against Bacillus subtilis and Staphylococcus aureus with an IC 50 of 151.1 and 346.8 μg/mL, respectively. These bacteria (Shewanella sp.) were also the ones with highest antitumor potential, demonstrating antiproliferative activity on HepG‐2 cells. Asparagopsis armata‐associated bacteria revealed to be a potential source of compounds with antitumor and antibacterial activity., Macroalgae‐associated bacteria have showed to be an interesting source of compounds with therapeutic potential. In this study, Asparagopsis armata‐associated bacteria reveal to be a potential source of compounds with antitumor and antibacterial activity.

Summary The aim of this work was to study the proximate composition and the bioactive profile of Bifurcaria bifurcata. It contains 73.31 ± 0.69% of moisture, 8.57 ± 0.11 g per 100 g dry weight (d.w.) of protein, 5.81 ± 0.14 g per 100 g d.w. of lipid content and 30.15 ± 0.00 g per 100 g d.w. of ash. The polyunsaturated fatty acids were the most abundant fatty acid (FA), accounting for 2426.56 mg per 100 g which represents 41.77% of the total FA. The methanolic fraction showed high quantity of polyphenols (220.01 ± 0.010 phloroglucinol equivalents g−1 extract), DPPH radical reduction capacity (EC50:58.82 μg mL−1) and oxygen radical absorbent capacity (3151.35 ± 119.33 μmol Trolox equivalents g−1 extract). The highest antimicrobial effect was observed against Pseudomonas aeruginosa (11.3 ± 1.5 mm) and Saccharomyces cerevisiae (IC50:17.07 μg mL−1) induced by methanolic and dichloromethane fractions, respectively. Dichloromethane fraction revealed the highest antitumor activity on Caco-2 and HepG-2 cells. Bifurcaria bifurcata can be a promising source of bioactive compounds and functional ingredients.

Proximate composition (ash, moisture, total protein, and fat contents) and fatty acid profile of Balistes capriscus (grey triggerfish) were assessed over a 6-months period (April to September, 2011) in animals captured along the coast of Peniche (Portugal). High protein (18.9% to 21.4%) and low lipid (0.5% to 0.8%) contents were determined. The highest lipid level was found in June-captured animals. High proportions of n-3 polyunsaturated fatty acids (n-3 PUFA) were observed (53.87 ± 2.00%) together with substantial quantities of oleic acid (27.58 ± 1.09%) and palmitic acid (16.52 ± 0.93%). Docosahexaenoic acid accounted for 77% of the total PUFA and was 7 times more abundant than eicosapentaenoic acid, and the n-3/n-6 ratio was 7.2. Gender did not influence lipid levels and the fatty acid profile, but seasonal variations were observed for PUFA and monounsaturated fatty acid contents. Overall, the nutritional properties of this underexploited species may be comparable to those of other lean fish species with higher economic value.

Background and purpose: The influence of apolipoprotein E (ApoE) polymorphism on clinical severity of multiple sclerosis (MS) is still controversial. Cigarette smoking has been suggested to influence the progression of disability in these patients. In this study, we aimed to investigate whether an interaction of smoking with the ApoE polymorphism influences the progression of disability in MS patients. Methods: Smoking history from 205 female patients with MS was obtained. Clinical data collected include age at onset, disease duration, annual relapse rate, the Expanded Disability Status Scale (EDSS) and the Multiple Sclerosis Severity Score (MSSS). ApoE polymorphism was examined in all patients and stratified according to smoking status and associations with the clinical data investigated. Results: There were no significant associations between cigarette smoking and any of the clinical characteristics in the whole group of patients. In women carrying the ApoE E4 isoform, smokers had a lower EDSS (P = 0.033) and MSSS (P = 0.023) in comparison with non-smokers. Conclusion: Our data suggest that in women with MS carrying the ApoE E4 isoform, cigarette smoking may have a protective influence on disease progression and accumulation of disability. These findings need to be confirmed by future large longitudinal studies.

This study evaluated the response of the Na+/H+ exchanger (NHE) to dopamine D1- and D2-like receptor stimulation in immortalized renal proximal tubular epithelial cells and freshly isolated renal proximal tubules from the spontaneously hypertensive rat (SHR) and their normotensive controls (Wistar Kyoto rats; WKY). Stimulation of D1-like receptors with SKF 38393 attenuated NHE activity in WKY cells (IC50=151 nM), but not in SHR cells. Stimulation of D2-like receptors with quinerolane (IC50=120 nM) attenuated NHE activity in SHR cells, but not in WKY cells. Forskolin was equipotent in SHR and WKY cells in inhibiting NHE activity. The effect of SKF 38393 was abolished by overnight treatment of WKY cells with cholera toxin (CTX, 500 ng ml−1), but not with pertussis toxin (PTX, 100 ng ml−1). The effect of quinerolane (1 μM) was abolished by overnight treatment of SHR cells with PTX, but not with CTX. The D3 receptor agonist 7-OH-DPAT (IC50=0.8 μM) attenuated NHE activity in SHR cells only. This effect was abolished by S-sulpiride and by overnight treatment with PTX. The D4 receptor agonist RBI 257 did not affect NHE activity. The 7-OH-DPAT inhibited NHE activity in freshly isolated renal proximal tubules from 4- and 12-week-old SHR and 12-week-old WKY, but not in freshly isolated renal proximal tubules from 4-week-old WKY. It is concluded that D3 receptors coupled to a Gi/o protein play a role in the handling of tubular Na+, namely through inhibition of the NHE activity, this being of particular relevance in the SHR, which fail to respond to D1-like dopamine receptor stimulation. British Journal of Pharmacology (2004) 142, 1343–1353. doi:10.1038/sj.bjp.0705893

1. The present study was designed to evaluate the nature of intervening agents in L-DOPA- and dopamine-induced neurotoxicity in Neuro-2A cells. 2. In the absence of cells and in conditions of light protection, at 37 degrees C, L-DOPA or dopamine (1 mM) in culture medium degraded spontaneously in a time-dependent manner, this being prevented by ascorbic acid (200 microM) and other antioxidants, namely glutathione (1 mM), N-acetyl-L-cysteine (1 mM), sodium metabisulphite (200 microM), but not N-ter-butyl-alpha-phenylnitrone (1 mM) and deferoxamine (100 microM). 3. The viability of Neuro-2A cells declined following treatment with L-DOPA or dopamine in a concentration- and time-dependent manner. The decrease in cell viability by L-DOPA (10+/-4% of control) or dopamine (15+/-4% of control) was markedly attenuated by antioxidants (ascorbic acid, glutathione, N-acetyl-L-cysteine and sodium metabisulphite). Autoxidation of L-DOPA or dopamine was accompanied by the formation of H(2)O(2) in a time-dependent manner, this being completely prevented by ascorbic acid at 24 h or markedly reduced at 48 h. 4. Protective effects of 100 U ml(-1) catalase (40+/-1% of control) against L-DOPA-induced cell death were lower than those conferred by 200 microM ascorbic acid (70+/-3% of control). Catalase-induced protection (59+/-5% of control) against dopamine-induced cell death was similar to that conferred by 200 microM ascorbic acid (57+/-4% of control). L-DOPA-induced neuronal cell death was also accompanied by increases in caspase-3 activity, this being insensitive to ascorbic acid. Dopamine-induced increase in caspase-3 activity occurred only when autoxidation of the amine was prevented by ascorbic acid. 5. It is suggested that in addition to generation of H(2)O(2) and quinone formation, L-DOPA- and dopamine-induced cell death may result from induction of apoptosis, as evidenced by increases in caspase-3 activity. Dopamine per se induces apoptosis by a mechanism independent of oxidative stress, as evidenced by the fact that increases in caspase-3 activity occurred only when autoxidation of the amine was prevented.