Search Results (778)

The present study provides an exhaustive exploration of twelve macroalgal species from the Adriatic Sea, including seven brown algae (Ericaria amentacea, Fucus virsoides, Cutleria multifida, Cystoseira compressa, Cystoseira corniculata, Gongolaria barbata and Padina pavonica), three green algae (Codium adhaerens, Codium vermilara and Ulva lactuca), and two red algae (Scinaia furcellata and Asparagopsis taxiformis). Matrix solid-phase dispersion (MSPD) was applied as the extraction technique, using generally recognized as safe (GRAS) solvents. The bioactive profile of the extracts was assessed through the quantification of total phenolic content (TPC) and antioxidant activity. Among the three phyla, U. lactuca, F. virsoides and S. furcellata exhibited the highest TPC (0.8, 26 and 3.0 mgGAE·g⁻¹) and antioxidant activity (1.9, 38 and 7.5 mgTE·g⁻¹), respectively. Targeted HPLC-MS/MS analysis enabled the identification of nineteen phenolic compounds across all taxa. Chlorophyta showed a characteristic profile enriched in coumarins, benzaldehydes and flavanones, including the selective detection of 7-hydroxycoumarin in species with higher antioxidant potential. Additionally, compounds such as chlorogenic, rosmarinic and caffeic acids exhibited taxon-specific distributions that may explain differences in antioxidant activity. Complementary untargeted ultra-high performance liquid chromatography quadrupole time-of-flight (UHPLC-QToF) metabolomics analysis provided broader coverage, revealing eighty metabolites spanning phenolics, sugars, organic acids, lipids, amino acids and their derivatives. Notably, the proposed detection of fatty acid esters of hydroxy fatty acids (FAHFAs) represents the first report of these compounds in macroalgae, alongside a pronounced presence of sulphated phenolics. Overall, these findings provide a robust baseline on the bioactivity and chemical composition of Adriatic macroalgae, highlighting their value as a natural source of functional compounds. Full article

A comparative analysis of the long-term dynamics of phytobenthos on the Black Sea coast from 1964 to 2020 has been conducted. The aim of the work was to assess changes in species composition, quantittive characteristics, and distribution of bottom vegetation under the influence of natural and anthropogenic factors. The research was carried out at three transects using standard hydrobotanical methods and analysis of climatic data. The results revealed significant structural reorganization of the communities: a decrease in the proportion of key brown algae (Ericaria crinita and Gongolaria barbata) by the middle of the observation period with partial recovery by 2020, an overall increase in biomass and species diversity, and increased role of epiphytes and green algae. An expansion of the depth range of the phytal zone and an increase in the presence of the deep-water species Phyllophora crispa were established. The main drivers of the transformation are increased anthropogenic pressure and climate change, which aligns with global trends. The obtained data are important for developing measures to preserve coastal ecosystems and can be used in monitoring the ecological state of the aquatic area. A promising direction for further research is the quantitative assessment of the role of the macrophytobenthos in this area in carbon sequestration. Full article

Background/Objectives: Fucoidan is a sulfated long-chain polysaccharide found mainly in sea cucumbers and brown algae. Studies suggest that fucoidan may play a role in treating various diseases, including metabolic syndrome and diabetes mellitus. The purpose of the current study was to investigate the effects of fucoidan isolated from brown algae on diabetic hyperglycemia and dyslipidemia. Methods: Two databases, PubMed and Embase, were searched to identify peer-reviewed articles written in English and published up to 30 June 2025. Studies reporting blood glucose and serum/plasma lipid levels of diabetic rodents treated with fucoidan or vehicle were included in the meta-analysis. Results: Forty-seven studies reported blood glucose levels. The pooled effect size for blood glucose levels was −2.26 (95% CI: −2.78 to −1.75), with substantial heterogeneity. Subsequent analyses showed that diabetic dyslipidemia was markedly improved in the fucoidan-treated group compared with the control. Conclusions: Fucoidan treatment could improve hyperglycemia and dyslipidemia in diabetic rodents. Full article

Macroalgae are increasingly recognised as promising sources of bioactive compounds with nutritional and functional relevance. This study investigated the biochemical composition of selected green, brown, and red marine macroalgae from the Mediterranean coast sampled at different seasons, focusing on fatty acid profiles, carotenoid composition, phenolic and flavonoid contents, antioxidant activity, and multivariate biochemical structuring. Fatty acid distributions were determined by Gas Chromatography (GC)-Flame Ionisation detector (FID), carotenoids were quantified and profiled by Liquid Chromatography–Mass Spectrometry (LC-MS), and total phenolic content, total flavonoid content, and antioxidant capacity (ABTS^•+ and DPPH^• methods) were assessed using standard spectrophotometric assays. Principal component analysis was applied to evaluate relationships among biochemical variables and taxonomic patterns. Brown macroalgae tended to exhibit more complex and enriched biochemical profiles, containing high proportions of long-chain n-3 polyunsaturated fatty acids, particularly eicosapentaenoic acid, elevated total carotenoid contents dominated by fucoxanthin, the highest total phenolic and flavonoid contents, and antioxidant activities. Green macroalgae were characterised by fatty acid profiles rich in saturated and C18 polyunsaturated fatty acids, while carotenoid compositions were dominated by lutein and siphonoxanthin. Red macroalgae exhibited comparatively simpler lipid and pigment patterns, characterised by palmitic acid and zeaxanthin as dominant components and lower total carotenoid levels. Principal component analysis revealed taxonomic structuring, with brown algae clearly separated from green and red groups, while seasonal differences were minor. Antioxidant activity closely clustered with carotenoids and total phenolic content, suggesting their combined contribution to radical-scavenging capacity. Overall, brown species appear as promising candidates for functional foods and nutraceutical applications. Full article

Sulfated polysaccharides (SPs), biologically active macromolecules from marine and terrestrial organisms, hold significant potential in revolutionizing cancer therapy. Characterized by their unique sulfate ester groups and structural diversity, SPs exhibit a broad spectrum of bioactivities, including immunomodulation, apoptosis induction, metastasis suppression, and angiogenesis inhibition. Prominent SPs, such as fucoidan from brown algae and carrageenan from red algae, have shown remarkable anticancer properties, either as standalone agents or in synergy with conventional therapies like chemotherapy and radiotherapy. Their mechanisms of action involve targeting critical pathways such as NF-kB, VEGF, and PI3K/Akt, disrupting cancer cell proliferation, invasion, and tumor microenvironment dynamics. SPs also enhance immune system responses, reduce chemotherapy-induced side effects, and exhibit antioxidant properties, making them versatile candidates in cancer treatment. Innovations like SP-based nanoparticles are addressing bioavailability and drug delivery challenges, providing targeted and sustained therapeutic effects while minimizing off-target toxicity. Despite their promise, challenges such as structural complexity, scalability, and clinical validation hinder their widespread adoption. This review provides a comprehensive analysis of SPs’ therapeutic potential, mechanisms, and emerging applications in oncology. It emphasizes the need for advanced extraction, characterization techniques, and clinical research to unlock their full potential, paving the way for novel, efficient, and safer cancer therapies. Full article

Brown algae are a valuable source of bioactive secondary metabolites, particularly polyphenols and sulfated polysaccharides with photoprotective and antioxidant activities. Among them, fucoidan stands out for its biocompatibility, biodegradability, and demonstrated photoprotective effects, mainly through antioxidant and anti-photoaging properties, making it a promising natural component for UV-protective formulations. This study developed polyelectrolyte complex sub-micron particles based on fucoidan and chitosan (F/Cs) to encapsulate quercetin (Q) as a natural UV-active antioxidant. Fucoidan from Sargassum filipendula was extracted and fractionated by ultrafiltration. An RCBD was used to optimize pH and F/Cs mass ratio. The optimal blank formulation (F/Cs = 1:1, pH 5.0) yielded sub-micron colloidal carriers with a mean hydrodynamic diameter of 421 ± 23 nm (PDI 0.252 ± 0.059) with ζ = +43.5 ± 1.6 mV. Quercetin-loaded particles (F/Cs/Q = 1:1:0.5) presented 915 ± 87 nm (PDI 0.278 ± 0.093) and ζ = +54.6 ± 1.2 mV. UV–Vis spectra evidenced UVB and partial UVA absorption for fucoidan and broad UVA/UVB coverage for quercetin, preserved upon encapsulation. Antioxidant activity was retained post-encapsulation (EC50, DPPH: 0.094 mg/mL; ABTS: 0.0749 mg/mL). These results demonstrate the potential of fucoidan–chitosan colloidal systems as multifunctional, biodegradable carriers for natural photoprotective agents, supporting their application in next-generation dermatological and cosmeceutical formulations. Full article

Alginate, a naturally occurring polysaccharide derived from brown algae, has emerged as a versatile cornerstone in the field of biomedical materials. Its widespread adoption is driven by its exceptional biocompatibility and the unique cation-dependent gelation defined by the “egg-box” model. This review examines the fundamental chemistry of alginate, detailing how its crosslinking mechanisms dictate the physicochemical properties essential for clinical performance. The discussion bridges the gap between polymer structure and diverse biomedical applications, including drug delivery, tissue engineering, and the clinical management of gastrointestinal reflux and wound care. Furthermore, the article evaluates the role of alginate-based systems in the biomedical and metabolic management of obesity and diabetes. By analyzing how alginate influences satiety, glycemic index modulation, and lipid absorption through biophysical mechanisms, this review highlights the transition from fundamental chemical architecture to practical clinical utility. By integrating structural chemistry with physiological impact, this work underscores the evolving potential of alginate-based materials as supportive and functional strategies in modern clinical care. Full article

Inflammatory bowel disease (IBD) is triggered by genetic predisposition and chronic inflammation, with aberrant activation of the innate immune complex NLRP3 inflammasome playing a pivotal role in its pathogenesis. In this study, we investigated the effects of a hot water extract from the brown alga Endarachne binghamiae (EB-WE) on the inhibition of NLRP3 inflammasome activation, with a focus on its antioxidant properties, in various inflammation models. In bone marrow-derived macrophages (BMDMs), NLRP3 inflammasome activation was induced using LPS and ATP, and EB-WE pretreatment (100, 200 µg/mL) significantly reduced the secretion of IL-1β and IL-18. Confocal immunofluorescence analysis further confirmed that EB-WE suppressed the formation of the NLRP3-ASC/caspase-1 complex. Furthermore, the in vivo anti-IBD efficacy of EB-WE was assessed using a DSS-induced mouse model, in which colonic inflammation and NLRP3-mediated responses were prominent. Oral administration of EB-WE (2 or 5 mg/day) markedly ameliorated clinical symptoms, such as weight loss, diarrhea, and rectal bleeding, and significantly reduced the disease activity index (DAI). EB-WE also decreased serum pro-inflammatory cytokine levels and the expression of NLRP3 inflammasome-related molecules in colon tissue at both the gene and protein levels. In both BMDMs and the IBD mouse model, we further analyzed the upstream regulatory pathway involving NOX2-iNOS. EB-WE efficiently inhibited the activation of the NOX-iNOS axis and NF-κB phosphorylation, thereby alleviating inflammasome activation associated with DSS-induced oxidative stress and neutrophil/macrophage infiltration. Collectively, these results demonstrate that EB-WE effectively suppresses the formation and activation of the NLRP3 inflammasome by modulating the NOX-iNOS axis and the NF-κB pathway via antioxidant mechanisms. These findings suggest that EB-WE holds promise as a novel marine-derived natural therapeutic agent for the treatment of chronic inflammatory diseases. Full article

The impact of light quality on pre-germling formation was studied in the edible macroalga Cladosiphon okamuranus, cultivated in subtropical Japan. While the conditions for germination remain unclear, successful cultivation typically occurs in deeper nursery sites where light quality might play a crucial role. Initially, we compared light wavelengths at various depths, revealing that blue light (400–500 nm) predominated at approximately 7.5 m, where aquaculture nets were used for germination. Two experiments were conducted using discoid thalli. In the first, thalli were grown under four light conditions (white, blue, red, and a combination of blue and red) in sterilized seawater or nutrient-enriched PESI medium. Blue light resulted in the highest pre-germling formation rates in sterilized seawater, and notable rates were observed in the PESI medium across all wavelengths except red. The second experiment involved culturing thalli in sterilized seawater under white, blue, and red light at varying intensities (25 or 100 µmol photons m⁻² s⁻¹). The consistent promotion of pre-germling formation was observed with blue light, whereas red light produced no effects. These findings highlight the importance of blue light for germination in C. okamuranus, which can aid in optimizing nursery site and incubation conditions. Full article

Obesity is a chronic systemic disorder frequently associated with multiorgan complications of inflammatory and metabolic origin. This study aimed to evaluate the histoprotective effects of Sargassum muticum, an invasive brown seaweed harvested from the Moroccan Atlantic coast, in cafeteria diet-induced obese rats. Thirty-five Wistar rats were divided into five groups: standard control, obese control (cafeteria diet), two obese groups treated with Sargassum muticum at 10% and 20%, and one group treated with orlistat at 30 mg/kg. After eight weeks, tissue samples were collected for a histopathological analysis. In untreated obese rats, histological examination revealed multiple abnormalities, including submucosal edema, vascular congestion, gastric inflammatory infiltration, pulmonary hemorrhage and lipid vacuoles, as well as hepatic, cardiac, pancreatic, and testicular lesions. Treatment with S. muticum, particularly at 20%, markedly improved these alterations, characterized by a significant reduction in inflammatory infiltration, vascular congestion, lipid vacuolization, and tissue degeneration, together with improved preservation of tissue architecture. These effects were superior to those observed with orlistat. The anti-inflammatory, antioxidant, and metabolic properties of S. muticum are likely due to its richness in bioactive compounds, notably phlorotannins, fucoxanthin, and sulfated polysaccharides. These findings confirm the therapeutic potential of S. muticum in preventing histopathological complications of obesity and pave the way for translational studies and potential nutraceutical applications in human obesity management. Full article

The biological activities of fucoidan from brown algae have attracted considerable attention. Degradation to low-molecular-weight fucoidan reduces viscosity and improves bioavailability, enhancing antioxidant and anti-inflammatory effects. Fucoidan was degraded using acetic acid combined with ⁶⁰Co γ-ray irradiation and fractionated by Bio-Gel P10 chromatography to obtain four fractions (AIF1–AIF4). The fractions were structurally characterized and assessed for in vitro radical-scavenging activity and modulation of oxidative stress markers in H₂O₂-induced RAW264.7 macrophages. Compared with the model group, all fractions significantly increased catalase (CAT) and superoxide dismutase (SOD) activities, with the highest increase of approximately 1.33 U/mgprot for CAT and 20.32 U/mgprot for SOD, while decreasing malondialdehyde (MDA) and intracellular reactive oxygen species (ROS) levels. Among the four fractions, AIF4, with the lowest molecular weight, exhibited the highest antioxidant activity. LMWF treatment also upregulated the mRNA expression of antioxidant-related genes (HO-1, SOD1, SOD2) and signaling molecules (PI3K and Akt), accompanied by increased protein levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and PI3K/Akt pathway components. These findings indicate that LMWF is closely associated with the regulation of the PI3K/Akt–Nrf2 signaling axis under oxidative conditions and support its potential application as a dietary antioxidant ingredient. Full article

Brown macroalgae are a valuable source of bioactive polysaccharides, particularly alginates and fucoidans, with significant potential for cosmetic and pharmaceutical applications. In this study, polysaccharides were extracted from four species (Padina pavonica, Sargassum ilicifolium, S. latifolium, and Turbinaria decurrens) collected along the Djibouti coastline. Structural characterization by FT-IR and ¹H-NMR revealed pronounced interspecific variability. Alginates displayed distinct mannuronate/guluronate (M/G) ratios, with Sargassum latifolium showing the highest and T. decurrens the lowest, reflecting differences in polymer composition and structural flexibility. Fucoidan spectra exhibited characteristic sulfate bands at 1217–1220 and 840 cm⁻¹, with lower transmission values for T. decurrens indicating a relatively higher degree of sulfation. Biological assays demonstrated that alginate extracts exhibited moderate antioxidant activity, whereas fucoidans showed significantly stronger radical scavenging (DPPH) and ferric reducing (FRAP) capacities, in some cases comparable to vitamin C. Fucoidans also displayed potent inhibition of skin-aging enzymes, with elastase inhibition reaching 62.1% for P. pavonica and tyrosinase inhibition peaking at 63% for S. ilicifolium at 0.5 mg/mL. These results highlight the critical role of structural features, particularly sulfation patterns, in determining biological activity. Overall, Djiboutian brown algal polysaccharides combine antioxidant and enzyme inhibitory properties, confirming their potential as multifunctional and sustainable marine-derived ingredients for cosmetic formulations. Full article

Alginate, primarily sodium alginate, is a biopolymer derived from brown algae or bacterial sources that forms hydrogels via ionic crosslinking with certain divalent cations. Its incorporation into soils, earthen materials, cementitious composites, and asphalt mixtures improves mechanical performance and durability. This review collates recent advances in alginate-based treatments for geotechnical and construction applications, highlighting how alginate dosage, substrate type, gelation method, mixing strategy, and curing regime influence mechanical strength, physical properties, and self-healing efficiency. In soil stabilization, alginate treatments increase unconfined compressive strength (UCS) by 0.2–1.5 MPa in sand, with some studies reporting increases of over 2 MPa. Reported UCS improvements in alginate-treated clayey soils generally fall within the range of 50–150% compared to untreated samples, although isolated studies document increases exceeding 200%, depending on material composition and curing conditions. In cementitious systems, alginate-based capsules and hydrogels facilitate self-healing, achieving high closure rates of 70–100% for microcracks <0.4 mm, with some studies achieving complete sealing of macrocracks up to 4 mm while also recovering significant mechanical strength. Depending on dosage and formulation, alginate can also serve as a viscosity-modifying admixture, increasing the plastic viscosity and yield stress of the fresh mix, with this thickening effect becoming pronounced at dosages above approximately 0.1 w/w% by cementitious binder mass. For asphalt pavements, alginate-encapsulated rejuvenators facilitate high healing efficiency under cyclic loading and thermal cycling; rheological tests confirm elevated complex modulus and improved viscoelastic response. This review also synthesizes an explanatory framework for the divergent results found in the literature, advocates for standardized experimental protocols and material characterization, and outlines future research directions to advance alginate as a suitable alternative to conventional stabilizers. Full article

This scoping review mapped the available evidence on marine algae-derived bioactive compounds, focusing on their biological activities related to collagen stabilization, matrix metalloproteinase (MMP) inhibition, and enamel remineralization in dental hard tissues. Four electronic databases (PubMed, Scopus, Embase, and Web of Science) were systematically searched following a predefined protocol. Original experimental studies involving human or animal dental hard tissues were included. Nine studies met the inclusion criteria. Brown algal derivatives, including fucoxanthin, fucosterol, and phloroglucinol, exhibited significant MMP inhibition and, in selected compounds, collagen cross-linking, contributing to enhanced mechanical properties and improved stability of collagen-rich matrices. In contrast, red algae extracts such as Lithothamnion calcareum primarily promoted enamel remineralization, achieving surface microhardness recovery comparable to or superior to 0.05% sodium fluoride. Alginate, a brown algae-derived polysaccharide, also demonstrated functional potential as a scaffold biomaterial through strong hydroxyapatite adsorption and suitability for three-dimensional scaffold fabrication. Overall, marine algae-derived compounds demonstrate biologically relevant activities that modulate collagen stability, enzymatic function, and mineral deposition processes. These findings highlight the pharmacological potential of marine bioactive compounds, with dental hard tissues representing a primary application context. However, further validation using clinically relevant models is required. Full article

Alginate is a widely used and versatile biopolymer with an ever-expanding range of applications in the pharmaceutical and biomedical industries. This highlights the importance of developing sustainable and renewable production sources. Conventional extraction methods, although effective, are often energy-intensive and rely on harsh chemicals. In this context, brown algae are a promising alternative due to their abundance and renewability. This study investigated the potential of Saccorhiza polyschides and Sargassum muticum as sources of sodium alginate (SA), thus optimising an extraction process that combines acid treatment with an alkaline step. The extracted biopolymers were characterised using FTIR, H-NMR, STA, SEM/EDX, viscosity measurements, dynamic light scattering, and spectrophotometric assays of residual polyphenols and proteins. The optimised extraction conditions produced yields above 20% of high-purity alginate. When compared with commercial SA, the extracted materials showed comparable quality while relying on a simplified, solvent-reduced protocol that improves process efficiency and reduces the environmental impact. These results demonstrate that S. polyschides and S. muticum are promising, locally available sources of high-quality sodium alginate, and that industrially relevant yields (>20%) can be achieved through an environmentally conscious two-step extraction process. Full article