Helena Abreu

Self employed

The European, Canadian, and Latin American seaweed industries rely on the sustainable harvesting of natural resources. As several countries wish to increase their activity, the harvest should be managed according to inte- grated and participatory governance regimes to ensure pro- duction within a long-term perspective. Development of regulations an...

Integrated Multi-Trophic Aquaculture (IMTA) systems are designed to mitigate the environmental problems caused by several forms of fed aquaculture. Gracilaria chilensis is commercially cultivated in Chile and experimental studies recommend it as an efficient biofilter in IMTA systems. Traditional bottom culture Gracilaria farms face production prob...

The promotion of dogs' nutrition, health, and well-being are highly valued by pet owners, leading to an increasing interest in pet food with alternative, functional, and more sustainable supplements, such as algae. Few studies have assessed the supplementation of dog food with individual algae species, but no information exists on combined macro- a...

Introduction In order to ensure lipid quality of cultured fish and an environmentally sustainable production, new alternative sources of EPA and DHA are needed to replace traditional lipid sources, such as fish oil. Methods Different combinations of alternative marine lipid sources rich in n-3 LC-PUFA available in the market were herein evaluated...

This study evaluated the replacement of fish oil (sardine oil) by different combinations of alternative marine lipid ingredients as sources of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in European sea bass ( Dicentrarchus labrax ) throughout 14 days of ice storage. A practical diet (SARDINE) was used as a control, which included 9%...

Sustainable farming of fish species depends on emerging new feed ingredients, which can alter the features of the digestive tract and influence animals’ overall health. Recent research has shown that functional feeds hold great potential for enhancing fish robustness by evoking appropriate responses at the intestine level. However, there is a lack...

In this study, the chemical composition and antioxidant profile of five edible macroalgae, Fucus vesiculosus, Palmaria palmata, Porphyra dioica, Ulva rigida, and Gracilaria gracilis, cultivated in fully controlled closed systems, were determined. Protein, carbohydrates, and fat contents ranged between 12.4% and 41.8%, 27.6% and 42.0%, and 0.1% and...

Algae can leverage aquaculture sustainability and improve the nutritional and functional value of fish for human consumption, but may pose challenges to carnivorous fish. This study aimed to evaluate the potential of a commercial blend of macroalgae (Ulva sp. and Gracilaria gracilis) and microalgae (Chlorella vulgaris and Nannochloropsis oceanica)...

Marine macroalgae are emerging as sustainable and healthy food, and a source of lipids with nutritional and bioactive properties. Nonetheless, the lipidome of macroalgae has been little explored compared to other photosynthetic organisms. Most of the literature has been devoted on the analysis of fatty acid (FA) from macroalgae, because of they are...

Macro- and microalgae are currently recognized sources of lipids with great nutritional quality and attractive bioactivities for human health promotion and disease prevention. Due to the lipidomic diversity observed among algae species, giving rise to different nutritional and functional characteristics, the mixture of macro- and microalgae has the...

Intensification of aquaculture practices is often associated with disease outbreaks. These outbreaks can heavily affect the production of several fish species such as European seabass (Dicentrarchus labrax) that is of high economic relevance in Mediterranean countries. Nutritional approaches are promising solutions to alleviate the burden caused by...

Algae feeds and fish gut microbiota have been given importance in the past few years because of the necessity to rely on sustainable ingredients in aquafeeds and the link of host-associated microbes to organismal health. But little is known about the potential of algae, particularly of micro- and macroalgae combination, to shape the intestinal bact...

The growing resistance from pathogens against antibiotics has increased the research for new compounds and strategies with antibacterial potential. Lipids from algae are emerging as natural and potent bioactive molecules with interesting results regarding the inactivation of bacteria, viruses, and fungi. The combination of algae lipids with innovat...

Algae have been consumed for millennia in several parts of the world as food, food supplements, and additives, due to their unique organoleptic properties and nutritional and health benefits. Algae are sustainable sources of proteins, minerals, and fiber, with well-balanced essential amino acids, pigments, and fatty acids, among other relevant meta...

This study evaluated the effects of agar waste (AW) dietary supplementation, obtained from the seaweed Gracilaria gracilis cultivated under two different spectral lights, neutral (NT) and blue (BL), on haematological parameters, inflammatory response, and antioxidant biomarkers of gilthead seabream (Sparus aurata). Three diets were prepared: i) a b...

The consumption of marine macroalgae has been linked with health benefits, albeit some actions, including genoprotection, remain underexplored. Hence, we evaluated the genoprotective potential of a mixture of Ulva rigida, Fucus vesiculosus and Gracilaria gracilis, through direct consumption or via indirect intake using fish (Sparus aurata) as a vec...

The role of dietary profiles in promoting or reducing the risk of multiple types of cancer is increasingly clear, driving the search for balanced foods and nutraceuticals. The red seaweed Grateloupia turuturu has been used as human food showing a balanced nutritional profile. This study aims to test in vivo chemopreventive effects of G. turuturu ag...

Seaweeds are considered healthy and sustainable food. Although their consumption is modest in Western countries, the demand for seaweed in food markets is increasing in Europe. Each seaweed species has unique nutritional and functional features. The preparation of blends, obtained by mixing several seaweeds species, allows the obtaining of maximum...

Seaweeds are an important marine resource and are currently used in a wide range of applications, such as food, feed, pharmaceuticals, cosmetics, nutraceuticals, and biomaterials. Seaweeds uptake a multitude of chemical elements from the environment, which can turn them into high-quality food products or pose a threat to human health. Therefore, kn...

The present study aimed to contrast the fatty acid (FA) profile of ascidians (Ascidiacea) and seaweeds (sea lettuce, Ulva spp. and bladderwrack, Fucus sp.) occurring in a coastal lagoon with versus without the influence of organic-rich effluents from fish farming activities. Our results revealed that ascidians and seaweeds from these contrasting en...

Algae are natural products with great potential as aquafeed ingredients, being rich in nutrients and bioactive compounds. They can improve fish health while being sustainable at social, economic, and environmental levels, contributing to the one health concept. In this study, two micro- (Nannochloropsis oceanica and Chlorella vulgaris) and two macr...

Grateloupia turuturu Yamada, 1941, is a red seaweed widely used for food in Japan and Korea which was recorded on the Atlantic Coast of Europe about twenty years ago. This seaweed presents eicosapentaenoic acid (EPA) and other polyunsaturated fatty acids (PUFAs) in its lipid fraction, a feature that sparked the interest on its potential application...

The red seaweeds Grateloupia turuturu and Porphyra umbilicalis are commonly used as human food, mainly in East Asia, being valuable nutritional sources. However, studies focusing on their composition and bioactivities are scarce. Thus, G. turuturu and P. umbilicalis hydroethanolic and water (infusion and decoction) extracts were prepared to charact...

Ulva macroalgae species are recognized to be an underexploited source of key nutrients, including proteins, fibers and minerals. The present work evaluated the nutritional value protein, ash, mineral composition, fat, fatty acid profile and dietary fiber of the green macroalgae Ulva rigida produced in an open land-based integrated multi-trophic aqu...

The effects of different light spectra on agar yield, composition and gel properties, pigment content and antioxidant activity of Gracilaria gracilis cultivated in a land-based IMTA-system were investigated. Total phenol content, antiradical activity and lipid peroxidation inhibitory capacity in the residue obtained from G. gracilis agar extraction...

Latitudinal diversity gradients have provided many insights into species differentiation and community processes. In the well‐studied intertidal zone, however, little is known about latitudinal diversity in microbiomes associated with habitat‐forming hosts. We investigated microbiomes of Fucus vesiculosus because of deep understanding of this model...

The valorization of seaweeds has generated unprecedented interest in recent years due to their unique chemical characteristics. The taxonomic differentiation between Chlorophyta, Rhodophyta, and Ochrophyta is often supported by their contrasting chemical characteristics. Polar lipids are the most abundant class of lipids in several seaweeds species...

Macroalgae of the genus Ulva have long been used as human food. Local environmental conditions, among other factors, can have an impact on their nutrient and phytochemical composition, as well as on the value of the seaweed for food and non-food applications. This study is the first to initiate a comparison between commercial Ulva spp. from differe...

This study evaluated the use of Gracilaria by-products in gilthead seabream diet to modulate intestinal bacterial community, physiological responses as well as skin and fillet attributes during cold storage. Fish were fed for 52 days with six experimental diets: i) a diet containing a commercial antioxidant (CTR), ii) a diet without antioxidant (NO...

The conchocelis life cycle stage of P. dioica represents an unexplored source of bioactive compounds. The aim of this study was to generate and characterise, for the first time, hydrolysates of conchocelis using a specific combination of proteases (Prolyve® and Flavourzyme®). Hydrolysate molecular mass distribution and free amino acid contents were...

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 control...

This study assessed both the effectiveness of a physical-mechanical rupture method and the ability of feed additives (phytogenic compounds, alginate oligosaccharide and nucleotides) to enhance the utilization of G. gracilis by European seabass. A commercial-based diet was used as control diet (CTRL) and compared with five isoproteic (53.5% Dry matt...

By-products obtained from seaweed processing appear as a promissory source of bioactive compounds that could be included in aquafeed to improve the sustainability of aquaculture. Therefore, the present study aimed to evaluate the effects of dietary supplementation with by-products obtained from the seaweed Gracilaria sp. on the stress response, ant...

Short-term effects of pCO 2 (700-380 ppm; HC-LC) and nitrate content (50-5 M; HN-LC) on photosynthesis, estimated by different pulse amplitude modulated (PAMs) fluorometers and by oxygen evolution, were investigated in Ulva rigida (Chlorophyta) under solar radiation (ex-situ) and in the laboratory under artificial light (in-situ). After 6-days of...

Algae are natural sources of nutrients, but the presence of anti-nutritional factors often compromises nutrient apparent digestibility coefficients (ADCs) in several fish species. In this study, physical-mechanical and enzymatic technological processing was applied to two seaweeds (Gracilaria gracilis and Ulva rigida) and three microalgae (Nannochl...

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 Codiu...

Green macroalgae of the genus Ulva, commonly known as sea lettuces, are currently traded worldwide for multiple applications, including human consumption. In this work, we evaluated the seasonal variation of the total content of lipids, esterified fatty acids (FAs) and polar lipids (the major carriers of FAs) at the level of the classes and molecul...

Antigenotoxic properties of plant- and plant-like derived foods may embody nutritional strategies against DNA damage. Marine macroalgae have shown DNA-protective effects, but their nutraceutical potential and the influence of growing conditions on these properties is underexplored. Hence, we aimed to assess the genoprotection potential of wild-harv...

Gracilaria gracilis and Nannochloropsis oceanica, single or blended, were tested in European seabass (Dicentrarchus labrax) diets. A control (CTRL) diet was compared with experimental diets including either 8% G. gracilis (GRA8), 8% N. oceanica (NAN8), or a blend of 4% of each alga (NAN4GRA4). After 106 days of feeding, growth, nutrient utilization...

Nutrition plays a crucial role in health promotion and disease prevention, and dietary-related factors are, in many cases, the leading risks for worldwide mortality and morbidity. Nowadays, consumer awareness of this fact has led to an increasing interest in food products that couple both these dimensions to an imperative third overall factor of in...

The incorporation of macroalgae on aquafeeds has been suggested to increase fish growth and organoleptic characteristics. Moreover, the potential of macroalgae to strengthen fish capacity to cope with different stressors is a challenging topic in the field of applied phycology. The adverse side effects of aqua-medicines, combined with the hypothesi...

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. tom...

The wild harvest and aquaculture of Ulva spp. has deserved growing attention in Europe. However, the impact of geographical origin on the biochemical composition of different species and/or strains is yet to be described in detail. Hence, the present study aimed to detect the variability of the lipidome of different species and/or strains of Ulva o...

Integrated Multi-Trophic Aquaculture (IMTA) systems are a circular economy paradigm that contribute towards making aquaculture more sustainable and competitive. However, despite being encouraged by European Union (EU) policies such as the Blue Growth Strategy, the Atlantic Action Plan and RIS3, there are socio-economic, administrative and regulator...

Gold nanoparticles (AuNPs) are one of the most studied nanosystems with great potential for biomedical applications, including cancer therapy. Although some gold-based systems have been described, the use of green and faster methods that allow the control of their properties is of prime importance. Thus, the present study reports a one-minute micro...

Ulva is a ubiquitous macroalgal genus of commercial interest. Integrated Multi-Trophic Aquaculture (IMTA) systems promise large-scale production of macroalgae due to their high productivity and environmental sustainability. Complex host–microbiome interactions play a decisive role in macroalgal development, especially in Ulva spp. due to algal grow...

The brown macroalgae Bifurcaria bifurcata have gained special attention due to their ability to biosynthesize linear diterpenes (rarely found in other species). However, the conventional extraction methods normally used to extract these compounds involve organic solvents and often high temperatures, leading to the degradation of thermo-labile compo...

Pterocladiella capillacea has been economically exploited for agar extraction in the Azores for many years. Harvesting dropped to a full stop in the early 1990s due to a population collapse, but restarted in 2013. Since then it has been intensively harvested and overexploitation must be prevented, with both sustainable harvesting and effective cult...

Some diet profiles are associated with the risk of developing cancer; however, some nutrients show protective effects. Porphyra umbilicalis is widely consumed, having a balanced nutritional profile; however, its potential for cancer chemoprevention still needs comprehensive studies. In this study, we incorporated P. umbilicalis into the diet of mic...

List of seaweed species that can be harvested in Azores is restricted and is differentiated between macroalgae for direct human consumption and macroalgae for processing industries

The impact of air-drying at 25 °C, brining at 25%, and dry-salting (at 28% and 40%) on the quality and nutritional parameters of Ulva rigida were evaluated over six months of storage. Overall, the main changes occurred in physical aspects during storage time, with U. rigida intensifying its yellow/browning tones, which were more evident in salt-tre...

The marine green macroalgal genus Ulva (Chlorophyta) requires the presence of a combination of regulatory morphogenetic compounds released by their associated epiphytic bacteria in addition to nutritional parameters. The activity of algal growth- and morphogenesis-promoting factors (AGMPFs) derived from bacteria was determined in a land-based integ...

The marine green macroalgal genus Ulva (Chlorophyta) requires the presence of a combination of regulatory morphogenetic compounds released by their associated epiphytic bacteria in addition to nutritional parameters. The activity of algal growth- and morphogenesispromoting factors (AGMPFs) derived from bacteria was determined in a land-based integr...

The red seaweeds Porphyra umbilicalis and Grateloupia turuturu are often used for human consumption. Nevertheless, there are knowledge gaps in studies focusing on their potential for genoprotection and in vivo studies assessing effects of whole algae intake. Thus, P. umbilicalis and G. turuturu were evaluated as genome integrity- and longevity-prom...

Diet composition, daily dietary intake and acute dietary changes have a big impact on modulating the microbial composition of the gut [1]. In fact, nowadays scientists recognize that diet is a key environmental factor for modulation of gastrointestinal microbiota composition and metabolic function and that the consumption of specific dietary ingred...

Fucus vesiculosus is an edible brown macroalga, with health benefits associated with its consumption and also a source of bioactive molecules. It is acknowledged that the biochemical composition of macroalgae changes when exposed to different environmental conditions occurring on different habitats, such as the water temperature, and light intensit...

Common in warm and cold temperate waters around Europe the cosmopolitan Halopteris scoparia (Linnaeus) Sauvageau is present in a broad temperature range, being harvested for commercial purpose in some locations. Several studies reported the importance of this species to the nutraceutical and cosmetics industries. The impact of its overexploitation...

Ulva species, green macroalgae, are widely distributed across the globe, being one of the most heavily traded edible seaweeds. Nonetheless, although this genus has been largely used in scientific studies, its lipidome remains rather unexplored. The present study sheds light over the lipid profile of Ulva rigida produced in a land-based integrated m...