Search Results (171)

Fucoidan, a complex sulfated polysaccharide derived from marine brown seaweeds, exhibits broad biological activities, including anticoagulant, antitumor, antiviral, anti-inflammatory and lipid-lowering effects. Fucoidan confers neuroprotection in animal models of a broad spectrum of brain disorders such as Parkinson’s disease (PD) and depression. However, the effect of fucoidan on gut-derived neuroinflammation and associated behavioral changes has been scarcely investigated. In comparison to fucoidan from other brown seaweeds, that from Fucus vesiculosus exhibited a better neuroprotective effect in vivo and more potent radical scavenging activity in vitro. Fucoidan from Laminaria japonica ameliorates behavioral disorders related to acute ulcerative colitis (UC) in aged mice. It is of interest to assess the effects of fucoidan administration on intestinal and brain inflammation in the acute colitis mouse model. Fucoidan treatment ameliorated DSS-induced intestinal pathology, reduced the inflammatory mediator expression in the gut and brain, and activated intestinal macrophages and cortical microglia in the UC mice. It also protected the intestinal mucosal barrier and blood–brain barrier as well as prevented neuronal damage, while alleviating anxiety-like behavior in UC mice. These results suggest fucoidan supplementation may help prevent brain disorders, such as depression and PD, potentially involving gut–brain axis-related mechanisms, as fucoidan suppresses gut-derived neuroinflammation. Full article

Extreme weather events, particularly marine heatwaves (MHWs), increasingly threaten aquaculture systems worldwide by impairing animal physiology and economical sustainability. This showcases the need to develop nutritional approaches that enhance animal performance under sub-optimal conditions. This study evaluated the effects of dietary supplementation with the brown macroalga Laminaria digitata (whole dried powder or extract) on the antioxidant status, digestive activity, and lipid metabolism of juvenile Sparus aurata exposed to a simulated MHW. Fish were fed four diets (control, 0.3% extract, and 0.3% or 1.5% powder) for 30 days before being exposed to a category III Mediterranean MHW. Under optimal temperature, macroalgae supplementation reduced oxidative status (lower catalase activity). The powder-feeds decreased lipid peroxidation, while the extract-feed elicited the opposite. All supplemented diets reduced proteolytic activity, and the extract-feed also decreased amylase activity. The MHW impaired gastrointestinal antioxidant defenses and liver lipid metabolism, decreasing catalase and glutathione S-transferase activities, as well as ΣPUFA n-6, 16:1 n-7, and 18:2 n-6 levels. The 0.3% powder-feed mitigated MHW-induced reductions in antioxidant activity, while both 0.3%-diets prevented thermal stress-related alterations on fatty acid profile. Overall, L. digitata powder at 0.3% was most effective at enhancing thermal stress resilience, supporting its value as a functional aquafeed ingredient. Full article

The extraction of antioxidant compounds from brown macroalgae is of growing industrial interest; however, the weak correlation often observed between polyphenol content and antioxidant activity challenges the conventional strategy of optimizing only extraction yield. This study introduces, for the first time in brown macroalgae, a functionality-driven optimization approach in which ultrasound-assisted extraction (UAE) conditions are optimized based on antioxidant activity as the primary response variable, rather than compound concentration. A green UAE process was developed and optimized for four edible brown algae (Himanthalia elongata, Eisenia bicyclis, Sargassum fusiforme, and Laminaria ochroleuca), considering algae amount, solvent type and concentration, extraction time, ultrasound power, and temperature. The optimized extracts achieved 69.17–94.68% DPPH inhibition, together with high antioxidant capacity supported by ORAC (18.63–491.30 μmol TE g⁻¹ DW) and FRAP (1.24–87.65 µmol Fe⁺² g⁻¹ DW) values, identifying E. bicyclis and H. elongata as the most promising species. Chromatographic analyses confirmed the presence of phlorotannins and carotenoid pigments such as fucoxanthin as the main contributors to antioxidant activity. Overall, this work validates a functionality-driven UAE optimization strategy for efficiently maximizing antioxidant activity in brown algal extracts. Full article

Boron (B) toxicity is a relevant problem in Mediterranean regions, where irrigation water may present high concentrations of this micronutrient. In this study, the potential of aqueous extracts from the brown macroalga Laminaria digitata and the diatom Phaeodactylum tricornutum, applied alone or in combination with metalloids (Se, Si) and micronutrients (Mn, Fe, Zn), was evaluated to improve the tolerance of tomato plants (Solanum lycopersicum L.) grown under excess B (15 mg L⁻¹). The extracts were applied foliarly, and growth parameters, gas exchange, chlorophyll content, mineral composition, B accumulation, oxidative stress, and metabolic profile were analyzed. Excess B significantly reduced root development, net photosynthesis, and metabolic balance, evidencing a strong physiological impact. The application of algal extracts partially mitigated these adverse effects, mainly through improvements in photosynthesis, water use efficiency, and the accumulation of osmoprotective metabolites (proline, tryptophan, glucose). In particular, L. digitata promoted a significant increase in total biomass and greater physiological recovery compared with P. tricornutum. Conversely, formulations enriched with metalloids and micronutrients did not provide consistent additional benefits and even induced metabolic imbalances. Multivariate analysis (PCA) confirmed that relative tolerance was associated with physiological and metabolic variables rather than nutritional changes. Overall, these results highlight the potential of algal extracts, especially L. digitata, as effective biostimulants to mitigate boron toxicity in tomato. Full article

In response to the growing demand for sustainable biomaterials in tissue engineering, we investigated the potential of structurally intact brown seaweed scaffolds derived from Laminaria digitata (L.D.) and Laminaria saccharina (L.S.), produced by a detergent-free, visible-light decellularization process aimed at preserving structural integrity. Blades were submerged in cold flow-through and aerated water with red (620 nm) and blue (470 nm) light exposure for 4 weeks. Histology, scanning electron microscopy (SEM), and micro-computed tomography (micro-CT) analyses demonstrated that the light decellularization process removed cells/debris, maintained essential structural features, and significantly increased scaffold porosity. Mechanical property analysis through tensile testing revealed a substantial increase in tensile strength post decellularization, with L.D. scaffolds increasing from 3.4 MPa to 8.7 MPa and L.S. scaffolds from 2.1 MPa to 6.6 MPa. Chemical analysis indicated notable alterations in polysaccharide and protein composition following decellularization. Additionally, scaffolds retained high swelling and fluid absorption capacities, critical for biomedical uses. These findings underscore that the decellularized L.D. and L.S. scaffolds preserved structural integrity and exhibited enhanced mechanical properties, interconnected porous structures, and significant liquid retention capabilities, establishing them as promising biomaterial candidates for soft-tissue reinforcement, wound care, and broader applications in regenerative medicine. Full article

The application of marine algae-derived biostimulants offers a sustainable approach to improving plant performance in aromatic and medicinal crops. This study investigated the effects of four macroalgal extracts and two commercial biostimulant products on the growth, physiology, and essential oil production of Lavandula angustifolia cultivated under greenhouse conditions at CREA, Pescia (Italy). Treatments included extracts from Ascophyllum nodosum (France and Greenland), Laminaria digitata (Iceland), Sargassum muticum (Italy), two commercial formulations (a seaweed-based and an amino acid-based biostimulant), and a control receiving only standard fertilization. Over a 10-week period, plants were evaluated for multiple parameters: plant height, leaf number and area, SPAD index (chlorophyll content), above- and below-ground biomass, flower production, microbial activity in the growth substrate, and essential oil yield. Algae extracts, particularly those from A. nodosum (Greenland) and S. muticum (Venice), significantly enhanced most parameters compared to the control and commercial products. These treatments yielded higher biomass, greater chlorophyll retention, increased flower number, and improved essential oil content. Rhizosphere microbial counts were also elevated, indicating a positive interaction between algae treatments and substrate biology. The study highlights the multifunctional nature of marine algae, whose complex composition of bioactive compounds appears to promote plant growth and secondary metabolism through multiple pathways. The superior performance of cold- and temperate-climate algae suggests a relationship between environmental origin and biostimulant efficacy. Compared to commercial inputs, the tested algae extracts showed broader and more consistent effects. These findings support the integration of macroalgae-based biostimulants into sustainable lavender cultivation strategies. Further research is recommended to optimize formulations, validate field performance, and explore synergistic effects with beneficial microbes or organic inputs. Full article

Kelp is a natural hydrogel material, which has been widely used in food industry. However, as a natural material, its properties have not been well explored. In this work, the surface and mechanical properties of kelp were investigated. The surface of kelp exhibited superoleophobicity and a self-clean property. The friction coefficient (COF) of the kelp surface was also low (<0.1). Interestingly, kelp demonstrated anisotropic mechanical properties either with or without metal ions. The tensile strength and toughness of kelp along with the growth direction (H) were better than those at the direction vertical to the growth direction (V). The adsorption of metal ions would significantly enhance the mechanical properties and ionic conductivity. Triboelectric nanogenerator (TENG) was assembled using kelp with NaCl, which showed excellent output performance (open-circuit voltage of 30 V, short-circuit current of 0.73 μA and charge transfer on contact of 10.5 nC). A writing tablet was prepared to use as the kelp-based self-powered tactile sensor. This work provides a new insight into natural kelp, which may be used as a renewable material. Full article

A number of marine resources have been exploited for a long time. Examples include Fucus and Laminaria, from which gelling agents are extracted. Only a few hundred thousand marine species are currently known, representing a tiny fraction of the estimated total of between 700,000 and one million species. This opens up numerous possibilities for innovation in the cosmetics industry. In this study, we present various species that are currently under-exploited, but which could have applications in hydration and photoprotection, for example. Algae and microalgae are worthy of interest because they can be used for hydration and anti-ageing purposes. Collagen can be extracted from animal sources and used as a substitute for collagen of bovine origin. From a marketing perspective, it is possible to market it as ‘marine collagen’. However, it is imperative to emphasize the significance of ensuring the sustainability of the resource. In accordance with this imperative, algae that are capable of being cultivated are distinguished by their enhanced qualities. Full article

Marine heatwaves (MHWs) are an emerging challenge for aquaculture, increasing the frequency and severity of disease outbreaks in farmed fish, weakening immunocompetence and compromising overall health and survival. As climate change stressors intensify, there is an urgent need for cost-effective and environmentally friendly strategies to enhance fish resilience. This study investigated the efficacy of Laminaria digitata, a brown macroalga, included in aquafeeds as powder (0.3% and 1.5%) or extract (0.3%) in improving the stress response of juvenile gilthead seabream (Sparus aurata) co-exposed to Vibrio harveyi infection during a category III MHW event. Under control conditions, L. digitata supplementation maintained or improved fish growth performance and overall well-being. After MHW exposure, the 1.5% powdered and 0.3% extract diets were more effective in mitigating thermal stress, reducing liver oxidative stress and lowering plasma cortisol levels. In infected fish, these diets improved resistance to V. harveyi, with reduced cortisol and alanine aminotransferase concentrations indicating hepatoprotective properties, and lower lipid peroxidation and decreased antioxidant enzyme activities reflecting an amplified capacity to counteract oxidative stress induced by inflammation. Overall, L. digitata is a promising aquafeed supplement, with the 1.5% powdered form offering a cost-effective alternative to the extract without compromising efficacy. Full article

Extreme weather events, such as marine heatwaves (MHWs), pose serious threats to the aquaculture sector, facilitating the occurrence of disease outbreaks and compromising farmed animals’ welfare and survival. Hence, finding eco-innovative strategies to improve animal immunocompetence is essential to assure aquaculture’s sustainability and resilience in a rapidly changing ocean. This study evaluated the immunostimulatory potential of Laminaria digitata powder (0.3% and 1.5%) and extract (0.3%) in juvenile gilthead seabream (Sparus aurata) exposed to a Vibrio harveyi outbreak during a Category III MHW event (T = 25.7 °C). Overall, L. digitata supplementation did not significantly affect fish immunocompetence under optimal rearing conditions (T = 21.4 °C; no infection), nor did it induce any adverse effects. However, both the powder (1.5%) and extract (0.3%) forms of L. digitata supplementation effectively mitigated the negative impacts prompted by the MHW and Vibrio harveyi infection—evidenced by improvements in fish health indicators, hematological parameters, leukocyte viability, granulocyte proportions, and reductions in peroxidase activity and immunoglobulin M levels. From an economic standpoint, supplementation with 1.5% L. digitata powder emerged as the most promising strategy, offering a practical balance between effectiveness and affordability for large-scale applications. These findings highlight the potential of L. digitata as an immunostimulatory aquafeed supplement, with promising benefits for fish health and resilience under adverse rearing conditions. Full article

Kombucha is a sweetened tea infusion fermented using a symbiotic culture of bacteria and yeast (SCOBY). Recently, kombucha has gained popularity due to its potential health benefits, attributed to its high antioxidant and probiotic properties. The aim of this research was to formulate a novel antioxidant-rich beverage with symbiotic benefits by utilizing ingredients such as Laminaria digitata (brown seaweed), cinnamon, and lavender adjuncts, alongside alternative substrates like acacia honey and conventionally used ingredients such as ginger (Zingiber officinale Roscoe). This study comprehensively evaluated parameters including pH levels, acidity, alcohol content, color, and antioxidant potential of the beverages. All kombucha beverages exhibited significantly high antioxidant potential levels, particularly in Honey Kombucha (HK) samples, which ranged between 164.44 and 164.78% 2,2-Diphenyl-1-picrylhydrazyl (DPPH) inhibition, and 155.44–155.29 µg Trolox Equivalent (TE)/mL for the Ferric-reducing antioxidant power (FRAP) assay on days 3 and 7. Sugar Kombucha Seaweed (SKS) and Sugar Kombucha Cinnamon (SKC) samples received the highest acceptability for flavor from the sensory panel, with scores of 87.5% and 70%, respectively. However, Honey Kombucha Ginger (HKG) received the lowest acceptability with only 12.5%. The added adjuncts and substrates significantly influenced the antioxidant potential compared to plain unfermented tea (PT). This research paper outlines well-characterized fermentation process for formulating health-promoting beverages utilizing locally sourced ingredients. Full article

Over recent decades, widespread declines of kelp forests have been reported along the European coast, prompting the need for effective and scalable restoration strategies. The green gravel technique, in which kelp gametophytes are seeded onto small rocks and cultivated in the lab before being outplanted, has shown promising results. In this study, we tested the effects of four commonly available substrates—granite, limestone, quartz, and schist—on the early development of Laminaria ochroleuca recruits under optimal laboratory conditions. All substrates supported gametophyte adhesion and sporophyte development. By week 6, quartz promoted the greatest recruit length (1.25 ± 0.16 mm), with quartz and limestone (1.54 ± 0.17 and 1.58 ± 0.14 mm, respectively) showing the best overall performance by week 7. Final recruit densities were similar across substrates, indicating multiple materials can support early development. Quartz and limestone showed both biological effectiveness and practical advantages, with limestone emerging as the most cost-effective option. Substrate selection should consider not only biological performance but also economic and logistical factors. These findings contribute to refining green gravel protocols and improving the feasibility of large-scale kelp forest restoration, although field validation is necessary to assess long-term outcomes under natural conditions. Full article

Utilizing deep eutectic solvents (DESs) combined with microwave-assisted extraction (MAE) provides a sustainable method for extracting bioactive compounds from the macroalgae Ascophyllum nodosum and Laminaria hyperborea. Two DES formulations, choline chloride/lactic acid (ChCl/LA) and sodium acetate/lactic acid (AcNa/LA), were evaluated under varying extraction conditions. For L. hyperborea, ChCl/LA at 150 °C for 10 min yielded a total phenolic content (TPC) of 15.34 mg GAE/g DW, with antioxidant activities measured by DPPH (34.55 mg TE/g DW) and ABTS (27.06 mg TE/g DW). Extending the extraction to 20 min at 130 °C increased the TPC to 19.12 mg GAE/g DW. A. nodosum exhibited higher bioactivity, with the TPC reaching 47.51 mg GAE/g DW under the same conditions. High-performance liquid chromatography (HPLC) identified significant phenolics such as 3,4-dihydroxybenzoic acid (678.05 µg/g DW) and vanillin (6718.5 µg/g DW). Antimicrobial assays revealed strong inhibition (zones > 20 mm) against Clostridium perfringens, moderate activity against Staphylococcus aureus, and selective activity against Escherichia coli. FT-IR confirmed the presence of phenolics, polysaccharides, and lipids. Thermal and structural characterization revealed that A. nodosum residue showed an amorphous structure, while L. hyperborea retained crystallinity with decomposition profiles indicating potential bioenergy potential. SEM images revealed significant cell wall disruption correlating with extraction efficiency. These results demonstrate DES–MAE as an effective, green strategy for producing high-value algal extracts and valorizing residual biomass for biotechnological applications. Full article