Microalgae are increasingly recognized as sustainable bioresources with applications in food, feed, nutraceuticals, and aquaculture. Among them, Spirulina (Limnospira platensis) and Microchloropsis gaditana (formerly Nannochloropsis gaditana) stand out due to their rich biochemical composition with industrial applications and high market value. This study separately investigates the seasonal variability in the biochemical composition of L. platensis cultivated in open raceway ponds and M. gaditana grown in closed photobioreactors. The results suggest a response to seasonal changes. L. platensis exhibited higher protein content in spring (47.82%) and summer (45.48%), while carbohydrate accumulation peaked in winter (50.85%). M. gaditana showed increased lipid (21.67%) and carbohydrate (14.56%) content in autumn compared to winter and summer, but with lower variations in response to seasonal environmental changes. This microalga exhibited higher FA 20:5 n-3 (EPA) levels in winter compared to summer. The dominant carbohydrate residue in both microalgae, present throughout all seasons, was glucose, which could be associated with the presence of beta-glucans, in addition to glycogen, reinforcing their bioactive potential. Pigment composition was also seasonally influenced in L. platensis, which accumulated more chlorophyll and phycocyanin in spring and summer, whereas M. gaditana showed elevated levels of neoxanthin in autumn and winter, and violaxanthin in spring. Although limited by a single sampling per season and the different cultivation systems size, this study provides preliminary observations of seasonal variations in biomass composition, highlighting that biochemical composition varies with season in a species-specific manner. Understanding these variations improves our knowledge of microalgal biochemical plasticity under outdoor conditions.

Microalgae are recognized as a valuable source of a panoply of compounds. In addition to the extensively investigated lipid fraction comprising polyunsaturated fatty acids (PUFA), microalgae biomass also encompasses other compounds with potentially relevant biological activities. This work innovatively repurposes the defatted biomass (DB) of Nannochloropsis oculata, highlighting its potential value beyond the lipid fraction. By subjecting the DB to enzymatic hydrolysis, we explored an underutilized resource, potentially reducing waste and promoting sustainable bioprocessing. The resulting soluble fraction was chemically characterized and a comprehensive assessment of its chemical and biological activities was performed to ascertain its potential applications. Those included antioxidant, anti-hypertensive, and antidiabetic capacities, as well as potential metabolic inhibition, anti-inflammatory, and antimicrobial activities. The chemical characterization revealed the presence of several low molecular weight peptides (<1.2 kDa), as well as polysaccharides. The DB exhibited a relevant antioxidant capacity of 3.15 mu molTrolox equivalent(TE)/mgfreeze-dried biomass(FDB) and an IC50 of 77.3 +/- 0.3 mu gprotein/mL concerning angiotensin-I converting enzyme inhibitory activity, while alpha-glucosidase activity was inhibited by 19.4 %. Biological activities revealed no relevant inhibition of metabolic activity, an immunosuppression potential and anti-inflammatory activity (decreased expression of all pro-inflammatory cytokines in lipopolysaccharide (LPS)-induced inflammation) was also observed. Moreover, significant antimicrobial activity was observed, particularly against Gram-positive bacteria. These results underscored the potential of the DB to be utilized within a biorefinery concept, thereby transforming it into a resource (co-product) rather than considering it as waste. This study is groundbreaking due to its integrative approach, being the first to report the potential bioactivities of non-lipid extracts from N. oculata cultivated under modulated stress conditions.

Fucoidan has been reported to present diverse bioactivities, but each extract has specific features from which a particular biological activity, such as immunomodulation, must be confirmed. In this study a commercially available pharmaceutical-grade fucoidan extracted from Fucus vesiculosus, FE, was characterized and its anti-inflammatory potential was investigated. Fucose was the main monosaccharide (90 mol%) present in the studied FE, followed by uronic acids, galactose, and xylose that were present at similar values (3.8–2.4 mol%). FE showed a molecular weight of 70 kDa and a sulfate content of around 10%. The expression of cytokines by mouse bone-marrow-derived macrophages (BMDMs) revealed that the addition of FE upregulated the expression of CD206 and IL-10 by about 28 and 22 fold, respectively, in respect to control. This was corroborated in a stimulated pro-inflammatory situation, with the higher expression (60 fold) of iNOS being almost completely reversed by the addition of FE. FE was also capable of reverse LPS-caused inflammation in an in vivo mouse model, including by reducing macrophage activation by LPS from 41% of positive CD11C to 9% upon fucoidan injection. Taken together, the potential of FE as an anti-inflammatory agent was validated, both in vitro and in vivo.

Chlorella vulgaris is a green microalga with a high chlorophyll content, representing a valuable source of green pigments for food applications. As the application of whole biomass can promote an unpleasant fish-like flavor, the use of chlorophyll extract can overcome this drawback. However, chlorophylls tend to easily degrade when out of the chloroplasts, decreasing their potential as a food ingredient. Thus, to study the suitable conditions for isolated chlorophylls preservation, in this work, the influence of temperature (4 to 60 °C), light (dark or 24 h photoperiod), alkaline conditions (with or without aqueous NaOH addition), and modified atmosphere (air or argon atmosphere) on the stability of the color in ethanolic solutions obtained from C. vulgaris were studied. The loss of green color with temperature followed the first-order kinetics, with an activation energy of 74 kJ/mol. Below 28 °C and dark conditions were suitable to preserve isolated chlorophylls. The addition of NaOH and an inert argon-rich atmosphere did not exhibit a statistically positive effect on color preservation. In the case study, cooked cold rice was colored to be used in sushi. The color remained stable for up to 3 days at 4 °C. Therefore, this work showed that C. vulgaris chlorophylls could be preserved in ethanolic solutions at room or lower temperatures when protected from light, allowing them to obtain a suitable natural food ingredient to color foodstuffs.

Porphyridium purpureum is a red saline microalga rich in protein and floridean starch with the ability to excrete high amounts of sulfated polysaccharides (sEPS) into the growth medium. This microalga has been used for feeding fish in aquaculture. P. purpureum is easily cultivated and could change its growth rate and composition in response to environmental variations. Thus, the effect of growth medium salinity (18, 32, and 50 g/L NaCl) on P. purpureum cell growth, biomass composition, and extracellular polysaccharides production yield and chemical structure were evaluated. A maximum growth of an estimated 5.7 x 10(6) cells/mL achieved at a salinity of 32 g/L NaCl, after 19 days of growth. Different from the almost unchanged biomass composition of algal cells, the yield and structure of sEPS were affected by the salinity of the growth media. The salinity of the growth media led to a slight change of the sulfation pattern of the glucuronoglucogalactoxylan, as the sEPS produced by P. purpureum growing at lower salinity tended to be more sulfated in the O-3 position of xylose and the O-6 position of glucose, whereas the sEPS at higher salinity tended to be more sulfated in the O-4 position of xylose and glucose. The sEPS produced at higher salinity also revealed higher linear 2-Gal, 3-Gal, and 4-Gal residues. In all samples, the most representative sugars residues were constituted by t-Xyl, t-Xyl-4S, 3-Xyl, 4-Xyl, t-Glc, 3-Glc-6S, t-Gal, and 2,3,4-Gal. The sEPS showed immunostimulatory effect on B lymphocytes in vitro and could be produced at large scale at an outdoor 800 L-flat panel photobioreactor with higher yield. These results pave the way for the potential use of P. purpureum sEPS to enhance humoral immune activity of fish in aquaculture.

Single-dose coffee capsules have revolutionized the coffee market, fueling espresso coffee popularity and offering access to a wide selection of coffee blends. Nevertheless, scarce information related to coffee powder and brew's combined volatile characterization is available. In this study, it is hypothesized that coffee brew aroma characteristics can be predicted based on coffee powder's volatile composition. For this, headspace solid-phase microextraction (HS-SPME) combined with comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry detection (GC × GC-ToFMS) was used. The data were combined via chemometric tools to characterize in depth the volatile composition of eight blends of capsule-coffee powder and respective espresso brews, simulating the consumer's perception. A total of 390 volatile compounds were putatively identified, 100 reported for the first time in roasted coffee or brews. Although the same chemical families were determined among the coffee powders and espresso brews, a different volatile profile was determined for each matrix. The Pearson correlation of coffee powders and respective brews allowed to identify 15 volatile compounds, mainly terpenic and esters recognized by their pleasant notes, with a strong relationship between the amounts present in both matrices. These compounds can be key markers to predict the volatile aroma potential of an espresso brew when analyzing the coffee powder.

MO245 exopolysaccharide (EPS) was produced in laboratory conditions from Vibrio genus microorganism isolated from bacterial mats found in Moorea Island. Its structure consists of a linear tetrasaccharide repeating unit →4)-β-D-GlcpA-(1→4)-α-D-GalpNAc-(1→3)-β-D-GlcpNAc-(1→4)-β-D-GlcpA-(1→ containing covalently-linked 5% of glucose, galactose, and rhamnose, determined by methylation analyses and NMR spectroscopy. The molecular weight, radius of gyration (Rg) and intrinsic viscosity, [η], determined by gel permeation chromatography with light scattering and viscosity detection, were 513 ± 4 kDa (PDI, 1.42 ± 0.01), 6.7 ± 0.3 dl/g and 56 ± 0.3 nm respectively. The chelation of the EPS with copper divalent ions leads to the instantaneous formation of gels. The structural similitude proposed, based in an equal ratio of GlcA to N-acetylated sugars and in the same type of glyosidic linkages present in the repeating unit (alternated 1→3 and 1→4 linkages), is translated into analogous physicochemical properties: MO245 EPS is a flexible polyelectrolyte, with scaling exponents similar to that described for HA. This similitude opens opportunities in future drug delivery, tissue engineering, and cosmetic applications.

Chlorella vulgaris is a green microalga approved for human consumption with high biological value due to its high protein content and polyunsaturated fatty acids composition. Moreover, this microalga is rich in starch and structural polysaccharides that could have potential to be valued as food ingredients. To fulfill this hypothesis, starch digestibility was evaluated in raw and boiled biomass, showing 43% and 71% of glucose released, respectively. The low extraction yield of starch obtained with water (13%) allowed to infer protein hindrance. This was overcome by 1 M and 4 M KOH aqueous solutions that allowed to obtain an additional 51% of starch. The final residue left showed that only 16% of total starch remained unextracted. KOH solutions allowed also to obtain galactans composed by 1,3-, 1,6- and 1,3,6-linked galactose residues. These linkages were also observed in the polysaccharides recovered from the growth medium, showing similarity between the exopolysaccharides and those present in the cell wall. The extracellular polymeric material revealed immunostimulatory effect on B lymphocytes. This opens the possibility of the use of both starch and exopolysaccharides of C. vulgaris as food ingredients.

High hydrostatic pressure (HHP) applied to wine in flexible plastic bottles has been studied as an enological practice for red wine aging, due to the oxidative reactions that can be promoted by this technology. To evaluate the effect of HHP on wine phenolic composition, a red wine treated with HHP was compared with different conventional wine aging processes, such as the use of wood and microoxygenation. The wine was pressurized at 500 MPa for 5 min at 20 °C and the same wine was also stored in oak barrels and treated with oak chips with or without microoxygenation. For comparison of the HHP effect, all wines were stored in polyethylene bottles. After 5 months, the monomeric anthocyanins, phenolic acids, and flavonols content of pressurized wines were lower in comparison with the other wine treatments. Nevertheless, pressurized wines showed a similar degree of tannin polymerization, pyranoanthocyanins content, and percentage of prodelphinidins in relation to the wine treated with microoxygenation and oak chips. HHP, possible by promoting a higher diffusion of oxygen into the wine, has the potential to be a novel oenological practice, producing red wines with a polymeric phenolic composition similar to those treated with wood aging processes.

Event Abstract Back to Event Biomedical potential of fucoidan, a seaweed sulfated polysaccharide: from a anticancer agent to a building block of cell encapsulating systems for regenerative therapies Tiago H. Silva1, 2, Catarina Oliveira1, 2, Lara L. Reys1, 2, Diana Soares Da Costa1, 2, Rámon Novoa-Carballal1, 2, Nuno M. Oliveira1, 2, Andreia S. Ferreira3, Cláudia Nunes3, Simone S. Silva1, 2, Albino Martins1, 2, Manuel A. Coimbra3, João F. Mano1, 2, Nuno M. Neves1, 2 and Rui L. Reis1, 2 1 University of Minho, 3B´s Research Group - Biomaterials, Biodegradables and Biomimetics, Portugal 2 ICVS/3B´s - PT Government Associated Laboratory, Portugal 3 Universidade de Aveiro, QOPNA, Departamento de Química, Portugal Introduction: Marine macroalgae or seaweeds synthesize a wide variety of polymers and smaller compounds with several bioactivities, among which the sulfated polysaccharides acquire greater relevance not only due to the reported antioxidant, antiviral and anticancer[1] activities, but also to the resemblance of extracellular matrix glycosaminoglycans found in the human body[2]. In this study, the potential of fucoidan (Fu) isolated from brown seaweed Fucus vesiculosus for therapeutical use has been evaluated, focusing in its performance as antitumoral agent (bioactive role) or as building block of cell encapsulating systems (structural role). Materials and Methods: The anticancer activity of Fu extracts was assessed by evaluating the cytotoxic behavior over two human breast cancer cell lines (MCF-7 and MDA-MB-231) in in-vitro culture, using human fibroblasts and endothelial cells (HPMEC-ST1 and MRC-5, respectively) as reference. Regarding the structural role, Fu was modified by methacrylation reaction (MFu) using methacrylic acid and further crosslinked using visible radiation and triethanolamine and eosin-y as photoinitiators. The photocrosslinking was performed on MFu solution droplets placed in a silica-based superhydrophobic surface[3], allowing the formation of particles[4] (since natural Fu is highly soluble in water and ion gelation is not effective). Biological performance of the developed particles was assessed by in vitro culture of fibroblasts and pancreatic cells (L929 and 1.1B4, respectively) in contact with MFu particles, up to 7 days. The ability of the developed materials to support adhesion and proliferation of cells was evaluated for both types of cells. Results and Discussion: The tested anticancer activity is not ubiquitous on Fu extracts, being dependent on its chemical features, with molecular weight (Mw) representing a particular role. Specifically, Mw values around 60 kDa exhibited cytotoxic effects to human breast cancer cell lines, while not affecting normal fibroblasts or endothelial cells (which represent the cells of the healthy tissue that would be closer to the tumor in a real situation). A concentration range of 0.2 to 0.3 mg mL-1 from the selected Fu extract could be considered as the therapeutic window for further studies. Regarding fucoidan’s role on innovative biomaterials, the developed MFu particles could support the proliferation of fibroblasts (L929), but also of human pancreatic beta cells (1.1B4), which tend to form pseudo-islets after 7 days in culture (Fig. 1). This pancreatic cells could be also successfully encapsulated, opening a new route for a diabetes mellitus type 1 therapeutic approach. Fig. 1: Confocal microscopy images of 1.1B4 cells cultured in the presence of fucoidan-based particles and organized in pseudo-islets (red – actin; blue – nuclei). Conclusion: The present work establishes fucoidan as a high performance building block for the development of advanced therapies for cancer (targeted therapy) or tissue and organ regeneration. It shed light on the relation between chemical structure and biological activity towards anti-cancer effect and proposes novel beta cell laden particles as injectable insulin producing systems to tackle diabetes. Funding from projects 0687_NOVOMAR_1_P (co-funded by INTERREG 2007-2013 / POCTEP), CarbPol_u_Algae (EXPL/MAR-BIO/0165/2013, funded by the Portuguese Foundation for Science and Technology, FCT), POLARIS (FP7-REGPOT-CT2012-316331) and ComplexiTE (ERC-2012-ADG 20120216-321266), funded by the European Union’s Seventh Framework Programme for Research and Development is acknowledged. ASF, SSS, NMO and DSC are also thankful to FCT for their individual fellowships.References:[1] Atashrazm F, Lowenthal RM, et al., “Fucoidan and Cancer: A Multifunctional Molecule with Anti-Tumor Potential”, Marine Drugs 13 (2015), 2327-2346.[2] Silva TH, Alves A, et al., “Marine algae sulfated polysaccharides for tissue engineering and drug delivery approaches”, Biomatter 2 (2012), 278-289.[3] Rial-Hermida MI, Oliveira NM, et al., "Bioinspired superamphiphobic surfaces as a tool for polymer-and solvent-independent preparation of drug-loaded spherical particles", Acta Biomaterialia 10 (2014), 4314–4322.[4] Reys LL, Silva SS, et al., “Fucoidan hydrogels photocrosslinked with visible radiation as matrices for cell culture”, submitted. Keywords: Tissue Engineering, Biomimetic, biomaterial, biomacromolecule Conference: 10th World Biomaterials Congress, Montréal, Canada, 17 May - 22 May, 2016. Presentation Type: Poster Topic: Naturally-derived materials and biopolymers Citation: Silva TH, Oliveira C, Reys LL, Soares Da Costa D, Novoa-Carballal R, Oliveira NM, Ferreira AS, Nunes C, Silva SS, Martins A, Coimbra MA, Mano JF, Neves NM and Reis RL (2016). Biomedical potential of fucoidan, a seaweed sulfated polysaccharide: from a anticancer agent to a building block of cell encapsulating systems for regenerative therapies. Front. Bioeng. Biotechnol. Conference Abstract: 10th World Biomaterials Congress. doi: 10.3389/conf.FBIOE.2016.01.00221 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 28 Mar 2016; Published Online: 30 Mar 2016. Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Tiago H Silva Catarina Oliveira Lara L Reys Diana Soares Da Costa Rámon Novoa-Carballal Nuno M Oliveira Andreia S Ferreira Cláudia Nunes Simone S Silva Albino Martins Manuel A Coimbra João F Mano Nuno M Neves Rui L Reis Google Tiago H Silva Catarina Oliveira Lara L Reys Diana Soares Da Costa Rámon Novoa-Carballal Nuno M Oliveira Andreia S Ferreira Cláudia Nunes Simone S Silva Albino Martins Manuel A Coimbra João F Mano Nuno M Neves Rui L Reis Google Scholar Tiago H Silva Catarina Oliveira Lara L Reys Diana Soares Da Costa Rámon Novoa-Carballal Nuno M Oliveira Andreia S Ferreira Cláudia Nunes Simone S Silva Albino Martins Manuel A Coimbra João F Mano Nuno M Neves Rui L Reis PubMed Tiago H Silva Catarina Oliveira Lara L Reys Diana Soares Da Costa Rámon Novoa-Carballal Nuno M Oliveira Andreia S Ferreira Cláudia Nunes Simone S Silva Albino Martins Manuel A Coimbra João F Mano Nuno M Neves Rui L Reis Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Single-dose coffee capsule system is a technology used to prepare espresso coffee which offers consumers the possibility to choose among several blends. However, the characterization of espresso coffees extracted with these systems, namely regarding polysaccharides structures and melanoidin content, is scarce. In order to define a carbohydrate and melanoidin composition pattern for single-dose espresso coffee base blends, a range of 6 commercial espresso coffee blends was studied. In addition, a decaffeinated blend and a blend supplemented with plant natural extracts were also included. The base blends showed galactomannans as the predominant polysaccharides over arabinogalactans, on the contrary of the decaffeinated blend. The blend supplemented with natural plant extracts showed glucose-rich polysaccharides. The labelled intensity of coffee single-dose seems to be related with the unknown brown compounds of melanoidins, present in the high molecular weight material of the brews. A pattern could be obtained for single-dose espresso coffee base blends, presenting an average per cup of 1.21g of total solids and 242mg of soluble dietary fibre, constituted by 62mg of galactomannans and 48mg of arabinogalactans, and 123mg of melanoidins. On average, 46% of espresso coffee low molecular weight compounds are adsorbed to the high molecular weight material, evidencing the importance of the adsorption/desorption phenomena for the properties of coffee dietary fibre.

There is an urgent need for antitumor bioactive agents with minimal or no side effects over normal adjacent cells. Fucoidan is a marine-origin polymer with known antitumor activity. However, there are still some concerns about its application due to the inconsistent experimental results, specifically its toxicity over normal cells and the mechanism behind its action. Herein, three fucoidan extracts (FEs) have been tested over normal and breast cancer cell lines. From cytotoxicity results, only one of the extracts shows selective antitumor behavior (at 0.2 mg mL-1 ), despite similarities in sulfation degree and carbohydrates composition. Although the three FEs present different molecular weights, depolymerization of selected samples discarded Mw as the key factor in the antitumor activity. Significant differences in sulfates position and branching are observed, presenting FE 2 the higher branching degree. Based on all these experimental data, it is believed that these last two properties are the ones that influence the cytotoxic effects of fucoidan extracts.

The paper analyses the Portuguese academics' perceptions about changes in their research activities and modes of knowledge production. Quantitative data gathered from an on-line national survey have been used to develop this analysis. Results reveal that the majority of academics declared that they were not involved in knowledge and technology transfer and that their research activities were not influenced by external sponsors or clients. However, they did recognise that were strong external pressures to reconfigure the epistemologies, ontologies and the institutional conditions under which knowledge is produced. The data analysis also reveals that academics recognise forms of hybridism between autonomy and endogenous dynamics and heteronomy and exogenous dynamics in the development of their research activities and knowledge production.

The use of edible films and coatings in food protection and preservation from renewable biopolymers has recently increased due to its nontoxicity, biocompatibility, and antimicrobial properties. Further, edible films can be an efficient vehicle for incorporating functional compounds, which improve its characteristics [1]. Grape pomace consisting of skins, seeds, and stems, is a rich source of phenolic compounds, lipids, polysaccharides and proteins. Since grape pomace is an abundant by-product, there is a high interest to use its extracts in order to improve the chitosan films properties.

Chitosan has been studied as a renewable polymer to form edible films allowing the incorporation of functional compounds. The aim of this work was to evaluate the effects in the chitosan films properties of the incorporation of grape pomace extracts: 0.15% of hot water extract (mainly polysaccharides), 0.15 and 0.3% of chloroform extract (wax), and 0.3 and 0.75% of n-hexane extract (oil). The evaluation of the surface morphology revealed that the films with the aqueous extract had the most homogeneous and smoother topography. The incorporation of higher proportion of wax and oil led to changes in mechanical properties of the films, namely lower resistance and stiffness. The chitosan-based films with 0.75% oil demonstrated a 75% decrease of solubility in water, due to their hydrophobicity, as confirmed by the contact angle and surface free energy measurements. The hydrophobic films showed higher antioxidant capacity in organic medium (ABTS and DPPH assays) whereas the most hydrophilic films showed an improvement in FRAP and reducing power assays. Therefore, all the chitosan-based films prepared by incorporation of these grape pomace extracts are promising for food shelf life extension.

In Portugal, reforms in higher education (HE) have been mainly conducted under the influence of a new political rationality. The dominant global trace of this rationality is the extension of economic and managerial logics to the set of HE activities, as well as the way of managing them and the professionals involved in their achievement.