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Microalgae and seaweed have been consumed as food for several decades to combat starvation and food shortages worldwide. The most famous edible microalgae species are Nostoc, Spirulina, and Aphanizomenon, in addition to seaweeds, which are used in traditional medicine and food, such as Nori, which is one of the most popular foods containing Pyropia alga as a major ingredient. Recently, many applications use algae-derived polysaccharides such as agar, alginate, carrageenan, cellulose, fucoidan, mannan, laminarin, ulvan, and xylan as gelling agents in food, pharmaceuticals, and cosmetics industries. Moreover, pigments (carotenoids particularly astaxanthins, chlorophylls, and phycobilins), minerals, vitamins, polyunsaturated fatty acids, peptides, proteins, polyphenols, and diterpenes compounds are accumulated under specific cultivation and stress conditions in the algal cells to be harvested and their biomass used as a feedstock for the relevant industries and applications. No less critical is the use of algae in bioremediation, thus contributing significantly to environmental sustainability. This review will explore and discuss the various applications of microalgae and seaweeds, emphasising their role in bioremediation, recent products with algal added-value compounds that are now on the market, and novel under-developing applications such as bioplastics and nanoparticle production. Nonetheless, special attention is also drawn towards the limitations of these applications and the technologies applied, and how they may be overcome. [ABSTRACT FROM AUTHOR]

Five Australian seaweed species, Phyllosphora comosa, Ecklonia radiata, Durvillaea potatorum, Sargassum fallax, and Cystophora siliquosa, thrive along the country's shorelines. Some of these seaweeds have recognized health benefits but have not been fully investigated in terms of their bioactive components and mechanisms of action. We employed ultrasonication with 70% methanol to extract phenolic compounds from these seaweeds and investigated a range of bioactivities for these extracts, including anti‐inflammatory activity exploring urease inhibition, nitric oxide scavenging activity, protein denaturation inhibition, and protease inhibition. Anti‐diabetic activities were investigated using α‐amylase and α‐glucosidase inhibition assays. Anti‐proliferative and anti‐mitotic activities were evaluated using yeast‐cell and green‐gram models, respectively. Our findings showed that C. siliquosa inhibited nitric oxide, urease, and protease activities, with S. fallax, P. comosa, and E. radiata exhibiting substantial inhibition of protein denaturation. E. radiata displayed inhibitory effects on both α‐amylase and α‐glucosidase, whereas P. comosa targeted only the α‐glucosidase enzyme, indicating different mechanisms of anti‐diabetic activity. In these anti‐mitotic assays, C. siliquosa exhibited low cell viability and a significant anti‐proliferative effect, particularly within 24 h, while E. radiata demonstrated notable inhibition at 48 h. LC‐ESI‐QTOF‐MS/MS investigation identified 48 phenolic compounds, including 19 phenolic acids, 20 flavonoids, and 9 other polyphenols. The presence of these compounds in extracts correlated with observed biological activities. These results support the potential health benefits of these seaweeds and link this activity to the presence of bioactive phenolics. [ABSTRACT FROM AUTHOR]

A celebrated result of Gromov ensures the existence of a contact structure on any connected, non-compact, odd-dimensional Lie group. In general, such structures are not invariant under left translation. The problem of finding which Lie groups admit a left-invariant contact structure resolves to the question of determining when a Lie algebra g is contact; that is, admits a one-form φ ∈ g ⁎ such that φ ∧ (d φ) k ≠ 0. In full generality, this remains an open question; however we settle it for the important category of the evocatively named seaweed algebras by showing that an index-one seaweed is contact precisely when it is quasi-reductive. Seaweeds were introduced by Dergachev and Kirillov who initiated the development of their index theory – since completed by Joseph, Panyushev, Yakimova, and Coll, among others. Recall that a contact Lie algebra has index one – but not characteristically so. Leveraging recent work of Panyushev, Baur, Moreau, Duflo, Khalgui, Torasso, Yakimova, and Ammari, who collectively classified quasi-reductive seaweeds, our equivalence yields a full classification of contact seaweeds. We remark that since type-A and type-C seaweeds are de facto quasi-reductive (by a result of Panyushev), in these types index one alone suffices to ensure the existence of a contact form. [ABSTRACT FROM AUTHOR]

BACKGROUND: The drive towards ensuring the sustainability of bioresources has been linked with better valorising primary materials and developing biorefinery pipelines. Seaweeds constitute valuable coastal resources with applications in the bioenergy, biofertiliser, nutrition, pharmaceutical and cosmetic sectors. Owing to the various sought‐after metabolites they possess, several seaweed species are commercially exploited throughout Western Europe, including Ireland. Here, four commercially relevant brown (Fucus serratus and Fucus vesiculosus) and red (Chondrus crispus and Mastocarpus stellatus) seaweed species were sampled during a spring tide in July 2021 on moderately exposed shores across three coastal regions in the west of Ireland. RESULTS: Significant regional differences were identified when specimens were analysed for carbohydrates (max. 80.3 μg glucose eq mg−1 DW), proteins (max. 431.3 μg BSA eq. mg−1 DW), lipids (max. 158.6 mg g−1 DW), pigment signature and antioxidant potential. Protein content for F. serratus recorded a twofold difference between northern and southern specimens. The antioxidant potential of F. vesiculosus and M. stellatus returned greater activity compared to F. serratus and C. crispus, respectively. Multivariate analysis showed a clear latitudinal pattern across the three western coastal regions (north, west and south) for both F. vesiculosus and F. serratus. CONCLUSION: F. vesiculosus thalli from the northwest were richer in pigment content while the F. serratus thalli from the northwest were richer in antioxidants. Such biogeographic patterns in the biochemical make‐up of seaweeds need consideration for the development of regional integrated aquaculture systems and the optimisation of the biomass content for targeted downstream applications. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The present study provides information on the effects of BPA on ROS production-related phenomena in the chlorophytes Ulva rigida and U. intestinalis, and on the mechanism they establish against BPA toxicity, at environmentally relevant concentrations (0.1–3 μg L−1). Up-regulated H2O2 generation seems to be a key factor causing oxidative damage. Interspecific differences, in terms of the mechanism and the temporal response to BPA toxicity were observed. BPA effects on U. rigida were more intense and appeared earlier (on 1D at 0.1 μg L−1) compared to U. intestinalis and mostly after 7D (LOEC: 0.3 μg L−1, Terminal time, Tt: 7D). In U. rigida, on 1-5D, the 'mosaic' type effect patterns ('models' 3A/3B) with 'unaffected' and 'affected' areas (dark content, positive H2DCF-DA staining signal/H2O2 production and chlorophyll autofluorescence signal loss) indicated a time-dependent manner. After 7D, only U. rigida cells with dark content formed aggregates, showing positive H2O2 production ('model' 4) or in some cells oxidative damages triggering retrograde signaling in the neighboring 'unaffected' areas ('model' 5). H2O2 overproduction (CTCF ratio) in U. rigida, on 1D at the lowest concentration and after 7D at 0.3–1/3 μg L−1, respectively, seems to stimulate (poly)phenolic production, in a dose- and time-dependent manner. U. intestinalis did not display severe BPA impact (i.e., 'models' 4, 5) at any exposures, although at a later time indicated a lower LOEC (0.1 μg L−1, Tt: 9D) than that in U. rigida. In U. intestinalis, H2O2 production does not appear to stimulate high (poly)phenolic amounts. [ABSTRACT FROM AUTHOR]

Globalization and climate change are both contributing to an increase in the number of potentially invasive algae in coastal areas. In terms of biodiversity and financial losses, the invasiveness of algae has become a significant issue in Orbetello Lagoon. Indeed, studies from the Tuscany Regional Agency for Environmental Protection show that the reduction in dissolved oxygen caused by algal diffusion is detrimental to fisheries and biodiversity. Considering that wakame and numerous other potentially invasive seaweeds are consumed as food in Asia, we assess the nutritional and nutraceutical qualities of two potentially invasive seaweeds: Valonia aegagrophila and Chaetomorpha linum. We found that both algae are a valuable source of proteins and essential amino acids. Even if the fat content accounts for less than 2% of the dried weight, its quality is high, due to the presence of unsaturated fatty acids. Both algae are rich in antioxidants pigments and polyphenols, which can be exploited as nutraceuticals. Most importantly, human gastrointestinal digestion increased the quantity of polyphenols and originated secondary metabolites with ACE inhibitory activity. Taken together, our data strongly promote the use of Valonia aegagrophila and Chaetomorpha linum as functional foods, with possible application in the treatment of hypertension and cardiovascular diseases. [ABSTRACT FROM AUTHOR]

Seaweeds are marine floras constituting in part to over 90% of the oceanic biomass. Despite the enrichments of seaweeds, their potentials are largely unexplored. Hence, this study evaluated the phytochemical screening, antimicrobial, anti-inflammatory and cytotoxicity activities of methanolic extracts of Ecklonia radiata and Jania verrucosa. E. radiata and J. verrucosa were collected from sites on the rocky shores of the Mbashe and Port St. John rivers on the Eastern Cape coast of South Africa during spring low tides. Qualitative phytochemical screening was carried out using standard protocol. The assessment of anti-inflammatory activity was done by inhibition of albumin denaturation assay and antimicrobial analysis was performed against six different pathogenic clinical isolates. The cytotoxicity effect of the methanolic extracts were further investigated on MDA-MB-231, HepG2, CaCo-2 and KMST-6 by (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) tetrazolium reduction assay (MTT assay). Phytochemical analysis revealed the presence of tannins, phenols, glycosides, and alkaloid for both extracts. The methanolic extracts of both seed weeds also possess antiinflammatory activity by inhibiting albumin denaturation. The average minimum inhibitory concentration (MIC) values of the plant extracts ranged from 160-10000 μg/mL. J. verrucosa methanolic extract had the most significant biological activity with the lowest MIC value (160 μg/ml). The cytotoxicity result showed that cells treated with the methanolic extracts of E. radiata and J. verrucosa have more cytotoxicity effect on MDA-MB-231 treated cells followed by HepG2 and CaCo-2. Non-cancerous cell line (KMST-6) however showed some selectivity in their activities. Among the cancer cell lines, HepG2 treated cells were significantly suppressed (p < 0.05) with both extracts compared to 5μM camptothecin (standard drug). In conclusion, E. radiata and J. verrucosa have potential for chemoprevention of human breast, good antiinflammatory and antibacterial activities. [ABSTRACT FROM AUTHOR]

The algae of the genus Gelidium can be found as frequent and abundant inhabitants in the rocky intertidal zone of the Mexican Atlantic. Six species of this genus have been reported in this region, but only Gelidium americanum has been confirmed with morphological and molecular tools, despite how important both tools have proven to be for the group. This research aimed to evaluate the Mexican specimens previously identified as Gelidium through morphological and molecular approaches, using rbcL and COI-5P markers. This study examined 20 specimens found living attached to the shell of a gastropod Stramonita rustica in the mid-high intertidal zone of the Mexican Atlantic and ten specimens found living on rocks. Phylogenetic analyses resolved these specimens to be an independent species closely related to G. gonzalezii, G. yangmeikengense, and G. indonesianum. Genetic distances and morphological information confirmed this. Gelidium rodrigueziae sp. nov. is described as a new species. It is distinguished from its related species by having a simpler branching pattern, a smaller number and size of medullary cells, and the smaller quantity and distribution of restricted internal rhizoid filaments around the medulla. [ABSTRACT FROM AUTHOR]

The drug target protein β-secretase 1 (BACE1) is one of the promising targets in the design of the drugs to control Alzheimer's disease (AD). Patients with neurodegenerative diseases are increasing in number globally due to the increase in the average lifetime. Neuro modulation is the only remedy for overcoming these age related diseases. In recent times, marine bioactive compounds are reported from Phaeophyceae (Brown Algae), Rhodophyta (Red Algae) and Chlorophyta (Green Algae) for neuro-modulation. Hence, an important attempt is made to understand the binding and stability of the identified bioactive compounds from the above marine algae using BACE1 as the molecular target. The docking study shows that the bioactive compound Fucotriphlorethol A (– 17.27 kcal/mol) has good binding affinity and energy compared to other compounds such as Dieckol (– 16.77 kcal/mol), Tetraphlorethol C (– 15.12 kcal/mol), 2-phloroeckol (– 14.98 kcal/mol), Phlorofucofuroeckol (– 13.46 kcal/mol) and the co-crystal (– 8.59 kcal/mol). Further, molecular dynamics simulations studies had been carried out for β-secretase 1 complex with Fucotriphlorethol A and Phlorofucofuroeckol for 100 ns each. Results are compared with that of the co-crystal inhibitor. Molecular dynamics simulations studies also support the stability and flexibility of the two bioactive compounds Fucotriphlorethol A and Phlorofucofuroeckol with BACE1. [ABSTRACT FROM AUTHOR]

This review highlights the substantial nutritional worth of seaweeds by examining their nutritional content and bioactivity. Seaweeds provide several health advantages, including cardio-protection, anti-tumor, antioxidative, antibacterial, anti-inflammatory, and immunostimulatory properties owing to their high content of polysaccharides, proteins, PUFAs, minerals, and bioactive chemicals. Bodybuilders love them because they are high in fiber and low in calories. Seaweeds are an interesting target for drug development because of their potential use in medicine and disease prevention. Nonetheless, a number of seaweeds remain underutilized, and further research on seaweed extracts is essential. For effective usage, further knowledge of bioactivity and mechanisms of action is also required. Seaweeds may also be used as fertilizer and biofuel. [ABSTRACT FROM AUTHOR]

In response to a global shift towards health-conscious and environmentally sustainable food choices, seaweed has emerged as a focus for researchers due to its large-scale cultivation potential and the development of bioactive substances. This research explores the potential anticancer properties of seaweed extracts, focusing on analyzing the impact of four common edible seaweeds in Taiwan on prostate cancer (PCa) cells' activity. The study used bioassay-guided fractionation to extract Cl80 from various seaweeds with androgen receptor (AR)-inhibitory activity. Cl80 demonstrated effective suppression of 5α-dihydrotestosterone (DHT)-induced AR activity in 103E cells and attenuated the growth and prostate-specific antigen (PSA) protein expression in LNCaP and 22Rv1 cells. Additionally, Cl80 exhibited differential effects on various PCa cell lines. Concentrations above 5 μg/mL significantly inhibited LNCaP cell proliferation, while 22Rv1 cells were more resistant to Cl80. PC-3 cell proliferation was inhibited at 5 μg/mL but not completely at 50 μg/mL. A clonogenic assay showed that at a concentration of 0.5 μg/mL, the colony formation in LNCaP and PC-3 cells was significantly reduced, with a dose-dependent effect. Cl80 induced apoptosis in all PCa cell types, especially in LNCaP cells, with increased apoptotic cells observed at higher concentrations. Cl80 also decreased the mitochondrial membrane potential (ΔΨm) in a dose-dependent manner in all PCa cell lines. Furthermore, Cl80 suppressed the migration ability of PCa cells, with significant reductions observed in LNCaP, 22Rv1, and PC-3 cells at various concentrations. These compelling findings highlight the promising therapeutic potential of C. lentillifera J.Agardh and its isolated compound Cl80 in the treatment of PCa. [ABSTRACT FROM AUTHOR]

Summary: The kinetic properties of Rubisco, the most important carbon‐fixing enzyme, have been assessed in a small fraction of the estimated existing biodiversity of photosynthetic organisms. Until recently, one of the most significant gaps of knowledge in Rubisco kinetics was marine macrophytes, an ecologically relevant group including brown (Ochrophyta), red (Rhodophyta) and green (Chlorophyta) macroalgae and seagrasses (Streptophyta). These organisms express various Rubisco types and predominantly possess CO2‐concentrating mechanisms (CCMs), which facilitate the use of bicarbonate for photosynthesis. Since bicarbonate is the most abundant form of dissolved inorganic carbon in seawater, CCMs allow marine macrophytes to overcome the slow gas diffusion and low CO2 availability in this environment. The present review aims to compile and integrate recent findings on the biochemical diversity of Rubisco and CCMs in the main groups of marine macrophytes. The Rubisco kinetic data provided demonstrate a more relaxed relationship among catalytic parameters than previously reported, uncovering a variability in Rubisco catalysis that has been hidden by a bias in the literature towards terrestrial vascular plants. The compiled data indicate the existence of convergent evolution between Rubisco and biophysical CCMs across the polyphyletic groups of marine macrophytes and suggest a potential role for oxygen in shaping such relationship. [ABSTRACT FROM AUTHOR]

Seaweeds, rich in high-value polysaccharides with thickening/gelling properties (e.g., agar, carrageenan, and alginate), are extensively used in the food industry for texture customization and enhancement. However, conventional extraction methods for these hydrocolloids often involve potentially hazardous chemicals and long extraction times. In this study, three red seaweed species (Chondrus crispus, Gelidium Corneum, and Gracilaria gracilis) commercialized as food ingredients by local companies were chosen for their native gelling biopolymers, which were extracted using water-based methodologies (i.e., (1) hydration at room temperature; (2) stirring at 90 °C; and (3) centrifugation at 40 °C) for production of sustainable food gels. The potential use of these extracts as bioinks was assessed employing an extrusion-based 3D printer. The present work aimed to study the gelation process, taken place during printing, and assess the effectiveness of the selected green extraction method in producing gels. To improve the definition of the printed gel, two critical printing parameters were investigated: the addition of locust bean gum (LBG) at different concentrations (0, 0.5, 1, 1.5, 2, and 2.5%) and printing temperature (30, 40, 60, and 80 °C). Rheological results from a controlled-stress rheometer indicated that gels derived from G. corneum and G. gracilis exhibited a lower gel strength (lower G′ and G″) and excessive material spreading during deposition (lower viscosity) than C. crispus. Thus, G′ was around 5 and 70 times higher for C. crispus gels than for G. corneum and G. gracilis, respectively. When increasing LBG concentration (0.5 to 2.5% w/w) and lowering the printing temperature (80 to 30 °C), an enhanced gel matrix definition for G. corneum and G. gracilis gels was found. In contrast, gels from C. crispus demonstrated greater stability and were less influenced by these parameters, showcasing the potential of the seaweed to develop sustainable clean label food gels. Eventually, these results highlight the feasibility of using algal-based extracts obtained through a green procedure as bioinks where LBG was employed as a synergic ingredient. [ABSTRACT FROM AUTHOR]

Featured Application: This article reports the bioactivity activity of macroalgae pigments against fungal agents of human skin diseases. Since this topic has not been thoroughly explored, this article presents a compilation of techniques to obtain the highest pigment yield, optimizing the methodology for both the extraction and separation of pigments, together with the anti-dermatophytic activity. Seaweeds have been explored as a natural resource of compounds of interest due to their bioactivities. Although many studies report the interest and the application of seaweeds in various areas, from food or human health to the economy, these data mostly focus on raw extracts and not on specific compounds, such as seaweed pigments. Fungal infections of the skin, nails, and hair caused by dermatophytes are the most common fungal infections worldwide. These pathologies require long periods of topical and/or systemic treatment associated with adverse effects and increased antifungal resistance. So, this study had two objectives: the first was to isolate and characterize the pigments of the seaweeds Calliblepharis jubata and Fucus vesiculosus; the second was to assess their antifungal activity. The extraction of pigments was performed using a method of extraction by exhaustion, and the purification was achieved via column chromatography. Three techniques were used to characterize the pigments: thin-layer chromatography (TLC), UV–visible spectrophotometry, and Fourier-transform infrared spectroscopy (FTIR). The antifungal activity against the three most common dermatophytes, Trichophyton rubrum, Trichophyton mentagrophytes, and Microsporum canis, was evaluated using a microdilution methodology, following the EUCAST international standards. It was possible to observe that the extracts obtained from the seaweed C. jubata, corresponding to the purified pigment phycobiliprotein, and the crude extract (an enriched extract) showed antifungal activity against the three fungal agents of human skin infection. [ABSTRACT FROM AUTHOR]

Fleshy macroalgae dominate the hard bottom, shallow waters along the Western Antarctic Peninsula (WAP). Although there are numerous reports on their ecology, geographic distribution, and to a lesser extent, vertical (depth) distribution in the northern portions of the WAP, much less is known farther south along the central portion of the WAP. Here we provide the first report of the vertical distributions of brown and red fleshy macroalgae in this region based on scuba-derived collections at 14 study sites between southern Anvers Island (64.8°S, 64.4°W) in the north and central Marguerite Bay (68.7°S, 67.5°W) in the south. Although several overstory brown macroalgal species that can be common along the northern WAP including Desmarestia anceps and Cystosphaera jacquinotii are mostly absent from the central WAP, the vertical distributions of the brown macroalgae Desmarestia menziesii and Himantothallus grandifolius are similar to the northern WAP even though their percent cover is much lower. Likewise, the vertical distribution of the 14 most widespread red macroalgae, where they occur, mirrored those known from the northern part of the WAP even though macroalgal cover, biomass, and total species richness declined markedly to the south across this region due to increasing sea ice concentrations. [ABSTRACT FROM AUTHOR]

Studies examining the relationship between seaweeds and the diversity of associated organisms have been attempted far less than those focusing on the influence of terrestrial plants. That is troublesome considering the growing number of studies reporting the decline or local loss of macroalgae because of ocean warming and climate change. Since the fate of macroalgae will have an influence on associated organisms, this brief overview examined the different roles played by macroalgae, making the distinction between morphological features associated with individual seaweed species and those associated with populations or habitats. Most studies at both (individual and population) levels have identified positive relationships between morphological features such as structural complexity (including fractal dimensions) and invertebrate biodiversity, and the abundance of various faunistic groups. Some of these relationships are stronger than others, often with complex outcomes, suggesting that the current and future ecological benefits provided by macroalgae are strongly species- and habitat-dependent. While the displacement or local-scale loss of seaweeds may continue because of climate change, the features identified here may become useful in light of conservation and restoration efforts. [ABSTRACT FROM AUTHOR]

Seaweeds or marine macroalgae are the oldest members of the plant kingdom, with a history extending back many hundreds of millions of years. Based on photosynthetic pigments, marine macroalgae can be classified into three groups, namely green algae commonly known as Chlorophyta, brown algae or Phaeophyta, and red algae also called Rhodophyta. In response to different kinds of environmental stress, marine algae develop defense strategies resulting in a significant level of structural chemical diversity, from different metabolic pathways. In this review a brief description of the most important seaweed compounds and their bioactivities are presented in this study. Seaweeds contain minerals, amino acids, proteins, fatty acids, lipids, polysaccharides, dietary fibers, vitamins, and various secondary metabolites, such as phenols, alkaloids, terpenes, and pigments. Many of these constituents possess high economic values and can be extracted to obtain antioxidative, anti-inflammatory, anticancer, antimicrobial, antifungal, antiviral, anti-obesity, antidiabetic, and antihypertensive products. Therefore, a new trend to isolate and identify bioactive compounds and constituents from marine algae has emerged. [ABSTRACT FROM AUTHOR]

Exopolysaccharides of marine microbial origin are in demand in industry. Seaweeds are marine macroalgae that harbor diverse microorganisms with unique properties. In this perspective, the present study was focused on screening and isolation of marine bacteria from seaweeds for the production of an exopolysaccharide, curdlan gum, which is a linear (1 → 3)-β-d-glucan neutral exopolysaccharide produced by bacteria under conditions of nitrogen starvation. It has unique thermo gelation properties and extensive applications. A total of 78 marine bacteria were screened and isolated from different seaweeds and assessed for their potential for curdlan gum production using aniline blue agar. Curdlan gum was recovered using acidic precipitation. High-yield isolate, screened from red seaweed (Gracilaria foliifera) was designated as "RSW2n" and chosen as a potential producer. The identity of the isolate RSW2n was revealed as Enterobacter cloacae subsp. dissolvens based on its morphology, biochemical characteristics, and 16S rRNA gene sequencing. Optimization of the process parameters such as initial pH, inoculum percentage, production time, and production medium volume by single factor at a time method yielded 4.2 g/L of curdlan gum using Enterobacter cloacae strain RSW2n. Characterization of curdlan gum produced by this marine isolate was carried out using XRD and FT-IR analyses. Further, production of curdlan gum by Enterobacter cloacae RSW2n with different carbon sources (glucose, sucrose, fructose, maltose, glycerol, dates syrup, palm oil and starch) was studied. [ABSTRACT FROM AUTHOR]

Non-native species (NNS) represent a threat to biodiversity, and their occurrence and distribution should be periodically updated and made easily available to researchers and policymakers. An updated inventory of macroalgal NNS currently present in the Azores was produced based on published reports. Data concerning the first report and the distribution in the archipelago are provided for each species, as well as their respective native ranges and possible vectors of introduction. The resulting list comprises 42 taxa, i.e., 8.05% of the marine flora presently reported in the Azores, with 16 new NNS recorded over the last decade. The most isolated islands of the Western Group presented lower numbers of NNS (4.25% and 6.25%). In contrast, the two islands with the most used marina for transatlantic recreational sailing presented higher numbers (12.90% and 16.87%). Shipping is the main introduction vector (68%), whereas most macroalgal NNS are originally from the Pacific Ocean (31%) and the Indo-Pacific (31%). The presence of 13 species is restricted to single islands, and no species is reported exclusively in the Western group. Asparagopsis armata is the only algal NNS reported from all islands of the Azores. Future work is proposed to support policymaking. [ABSTRACT FROM AUTHOR]

In a few Southeast Asian nations, seaweeds have been a staple of the cuisine since prehistoric times. Seaweeds are currently becoming more and more popular around the world due to their superior nutritional value and medicinal properties. This is because of rising seaweed production on a global scale and substantial research on their composition and bioactivities over the past 20 years. By reviewing several articles in the literature, this review aimed to provide comprehensive information about the primary and secondary metabolites and various classes of bioactive compounds, such as polysaccharides, polyphenols, proteins, and essential fatty acids, along with their bioactivities, in a single article. This review also highlights the potential of seaweeds in the development of nutraceuticals, with a particular focus on their ability to enhance human health and overall well-being. In addition, we discuss the challenges and potential opportunities associated with the advancement of pharmaceuticals and nutraceuticals derived from seaweeds, as well as their incorporation into different industrial sectors. Furthermore, we find that many bioactive constituents found in seaweeds have demonstrated potential in terms of different therapeutic attributes, including antioxidative, anti-inflammatory, anticancer, and other properties. In conclusion, seaweed-based bioactive compounds have a huge potential to play an important role in the food, nutraceutical, and pharmaceutical sectors. However, future research should pay more attention to developing efficient techniques for the extraction and purification of compounds as well as their toxicity analysis, clinical efficacy, mode of action, and interactions with regular diets. [ABSTRACT FROM AUTHOR]

The IUCN Red List of Threatened Species is an authoritative tool in biodiversity conservation. Whilst IUCN criteria have been applied successfully to groups such as birds and mammals, a Red List assessment of British seaweeds in 2021 revealed that the categories to which seaweed species were assigned were dependent on how the criteria were applied. Here, this seaweed assessment is used as a case study with which to evaluate the IUCN methodology for use with 'non-standard' groups of organisms. A data-driven assessment of red (Rhodophyta), green (Chlorophyta) and brown (Phaeophyceae) seaweeds, which applied three (A, B and D) of the five IUCN criteria (A–E), categorized 13% of 617 British species as threatened. Following peer review, only 7% of species were categorized as threatened (1% Critically Endangered—CR, 3% Endangered—EN, 3% Vulnerable—VU), and 55% as Data Deficient. This reduction in species categorized as threatened suggests that strict application of the IUCN criteria may, at least for the seaweeds, over-estimate threat. As a result of this assessment, recommendations include the need for a more unified monitoring system and a review of the suitability for/application of the IUCN assessment criteria to some types of organisms. For example, in clonal populations, it is not possible to count individuals, and complex life histories cause additional complications. IUCN criteria must be applicable to a wide range of organisms, including seaweeds. [ABSTRACT FROM AUTHOR]

Diabetes mellitus, a metabolic autoimmune disease caused by the consequences of expanding urbanization on lifestyle, is the third leading cause of death worldwide. However, unpleasant side effects and insufficient glucose control are drawbacks of contemporary diabetic treatment. Due to the undesirable side effects of the currently available antidiabetic drugs, the investigation for an effective natural-based antidiabetic therapy is essential to combating diabetes and its adverse effects. Algae are currently gaining popularity in the pharmaceutical and cosmetic sectors due to their ability to produce a wide range of bioactive compounds. Seaweed extracts have been shown to have promising bioactive molecules with anti-inflammatory, antioxidant, and hypoglycemic effects, making them suitable for the treatment of diabetes. The study aimed to provide valuable insights into the potential therapeutic benefits of marine green algae extracts in the management of diabetes in Alloxan-induced diabetic albino rats. The induction of diabetes in rats occurred intravenously administrated via a single dose of Alloxan at 150 mg/kg b. w. Then, rats were divided into four different groups: negative control group; diabetic control group; diabetic treated group receiving green algae crude extract and diabetic treated group receiving red algae crude extract. Data analysis of the biochemical investigations was performed using appropriate statistical methods to determine the significance of algae extract on diabetic animal models after 6 weeks of treatment. Preliminary results showed that the administration of seaweed (Green and Red Algae) extracts significantly reduced the hyperglycemic, hypercholesterolemia, and hyperlipidemia levels in diabetic-treated rats as compared to the diabetic untreated rats. Based on the above findings, the current research provided antidiabetic activity of marine algae against diabetes and its complications. [ABSTRACT FROM AUTHOR]

Seaweeds have been generally utilized as food and alternative medicine in different countries. They are specifically used as a raw material for wine, cheese, soup, tea, noodles, etc. In addition, seaweeds are potentially good resources of protein, vitamins, minerals, carbohydrates, essential fatty acids and dietary fiber. The quality and quantity of biologically active compounds in seaweeds depend on season and harvesting period, seaweed geolocation as well as ecological factors. Seaweeds or their extracts have been studied as innovative sources for a variety of bioactive compounds such as polyunsaturated fatty acids, polyphenols, carrageenan, fucoidan, etc. These secondary metabolites have been shown to have antioxidant, antimicrobial, antiviral, anticancer, antidiabetic, anti-inflammatory, anti-aging, anti-obesity and anti-tumour properties. They have been used in pharmaceutical/medicine, and food industries since bioactive compounds from seaweeds are regarded as safe and natural. Therefore, this article provides up-to-date information on the applications of seaweed in different industries such as pharmaceutical, biomedical, cosmetics, dermatology and agriculture. Further studies on innovative extraction methods, safety issue and health-promoting properties should be reconsidered. Moreover, the details of the molecular mechanisms of seaweeds and their bioactive compounds for physiological activities are to be clearly elucidated. [ABSTRACT FROM AUTHOR]

Simple Summary: The French Polynesian islands represent a unique insular system in the Pacific Ocean. Previous surveys of the marine flora of French Polynesia were mostly established on traditional morphology-based taxonomy. DNA barcoding allowed us to provide a major revision of French Polynesian marine flora, with an updated total of 702 species from French Polynesia, including 119 species of Chlorophyta, 169 Cyanobacteria, 92 Ochrophyta, 320 Rhodophyta, and 2 species of seagrasses (Alismatales)—nearly a two-fold increase from previous estimates. In addition to improving and refining our knowledge of French Polynesian marine flora, this study also provides a valuable DNA barcode reference library for identification purposes and future taxonomic and conservation studies. A significant part of the diversity uncovered corresponds to unidentified lineages, which will need careful taxonomic examination. Located in the heart of the South Pacific Ocean, the French Polynesian islands represent a remarkable setting for biological colonization and diversification, because of their isolation. Our knowledge of this region's biodiversity is nevertheless still incomplete for many groups of organisms. In the late 1990s and 2000s, a series of publications provided the first checklists of French Polynesian marine algae, including the Chlorophyta, Rhodophyta, Ochrophyta, and Cyanobacteria, established mostly on traditional morphology-based taxonomy. We initiated a project to systematically DNA barcode the marine flora of French Polynesia. Based on a large collection of ~2452 specimens, made between 2014 and 2023, across the five French Polynesian archipelagos, we re-assessed the marine floral species diversity (Alismatales, Cyanobacteria, Rhodophyta, Ochrophyta, Chlorophyta) using DNA barcoding in concert with morphology-based classification. We provide here a major revision of French Polynesian marine flora, with an updated listing of 702 species including 119 Chlorophyta, 169 Cyanobacteria, 92 Ochrophyta, 320 Rhodophyta, and 2 seagrass species—nearly a two-fold increase from previous estimates. This study significantly improves our knowledge of French Polynesian marine diversity and provides a valuable DNA barcode reference library for identification purposes and future taxonomic and conservation studies. A significant part of the diversity uncovered from French Polynesia corresponds to unidentified lineages, which will require careful future taxonomic investigation. [ABSTRACT FROM AUTHOR]

Conventional conservation techniques such as drying, salting or freezing do not allow for preserving the original characteristics of seaweeds. The present work aims to study the impact of minimal processing, in particular "Modified Atmosphere Packaging" (MAP), on the physicochemical characteristics and food safety of two seaweed species, "laver" (Porphyra umbilicalis) and "sea-lettuce" (Ulva lactuca), stored at 6 °C for 15 days. Different parameters were evaluated using analytical methods, namely the composition of headspace gases, color, texture, microorganisms, and volatile organic compounds (VOCs). The main findings of this study were that the MAP treatment was able to inhibit the respiration rate of minimally processed seaweeds, also preserving their color and texture. There was a remarkable reduction in the microbial load for P. umbilicalis treated under modified and vacuum atmospheres, and U. lactuca exhibited relatively steady values with no notable differences between the treatments and the control. Therefore, during the 15-day study period, both seaweeds met the requirements for food safety. GC–TOF-MS allowed to conclude that both MAP and vacuum treatments were more efficient in maintaining the odor characteristics of U. lactuca compared to P. umbilicalis with no significant differences throughout the storage days. Metabolic responses to diverse sources of abiotic stress seemed to account for most of the changes observed. [ABSTRACT FROM AUTHOR]

According to the National Institute of Health, more than 80% of microbial infections are biofilm-associated, including chronic lung, wound and ear infections. Pseudomonas aeruginosa is an opportunistic pathogen that causes chronic nosocomial infection in immune-compromised and cystic fibrosis patients worldwide and is a common cause of urinary tract and burn infections. Its ability to form biofilm makes them highly resistant to antibiotics and the host's immune defense system. Biofilm produced by Pseudomonas aeruginosa is made up of exopolysaccharides such as pel, alginate and psl. Different strategies are reported in the control of biofilm formation. The present work focuses on targeting pellicle (pel) polysaccharide biosynthesis in Pseudomonas aeruginosa using a computational approach. Pel polysaccharide biosynthesis involves seven proteins present in the cytoplasmic, inner, periplasmic and outer membranes of Pseudomonas aeruginosa. In the current study, Pel D was taken as the target for inhibition of pel polysaccharide production. The marine environment provides a novel array of metabolites with unique structural features and bioactivities. Recently, metabolites derived from seaweeds or marine macroalgae have attracted increasing consideration for the development of novel drugs. In this perspective, thirty-nine metabolites reported in brown seaweed Sargassum were chosen as the source for druggable molecules (ligands). The structures of these metabolites were retrieved from the Seaweed Metabolite Database. Molecular docking was performed using PyRx software. Four metabolites of Sargassum were found to exhibit high binding affinity with target protein when compared to ibuprofen, a non-steroidal anti-inflammatory candidate drug reported for inhibition of biofilm control in Pseudomonas aeruginosa. The top four metabolites with high binding affinity were assessed for physicochemical, pharmacokinetic and drug-likeness properties through in silico analysis. Hence this study will pave the direction for exploring the potential of less explored seaweed metabolites as therapeutic mediators for the control of Pseudomonas biofilm infection. [ABSTRACT FROM AUTHOR]

Foods enriched with nutritional compounds and biological activities, especially antioxidants, are considered healthier for human and/or animal consumption. Seaweeds are rich sources of biologically active metabolites and are used as functional foods. In this study, proximate compositions, physicobiochemical characteristics and oil oxidative stability were analyzed for 15 abundant tropical seaweeds (four green—Acrosiphonia orientalis, Caulerpa scalpelliformis, Ulva fasciata, Ulva lactuca; six brown—Iyengaria stellata, Lobophora variegate, Padina boergesenii, Sargassum linearifolium, Spatoglossum asperum, Stoechospermum marginatum; and five red—Amphiroa anceps, Grateloupia indica, Halymenia porphyriformis, Scinaia carnosa, Solieria chordalis). All seaweeds were analyzed for the proximate composition, including moisture content, ash content, total sugar content, total proteins, total lipids, crude fiber, carotenoid content, total chlorophyll content, proline, iodine content, nitrogen-free extract, total phenolic content and total flavonoid content. Green seaweeds showed higher nutritional proximate composition, followed by brown and red seaweeds. Among the different seaweeds, Ulva, Caulerpa, Sargassum, Spatoglossum and Amphiroa showed high nutritional proximate composition compared to other seaweeds. High cation scavenging, free radical scavenging and total reducing activities were observed for Acrosiphonia, Caulerpa, Ulva, Sargassum, Spatoglossum and Iyengaria. It was also observed that 15 tropical seaweeds contained negligible amounts of antinutritional compounds, including tannic acid, phytic acid, saponins, alkaloids and terpenoids. Nutritionally, green and brown seaweeds provided higher sources of energy (150–300 calories per 100 g) compared to red seaweeds (80–165 calories per 100 g). Additionally, this study also confirmed that tropical seaweeds improved the oxidative stability of food oils and, therefore, might be recommended as natural antioxidant additives. The overall results confirm that tropical seaweeds are potential sources of nutrition and antioxidants and may be explored as functional food, dietary supplementation or animal feed. Additionally, they may also be explored as food supplements for fortifying food products, as food toppings or for garnishing and seasoning foods. However, a human or animal toxicity analysis is required before any conclusive recommendation for daily food or feed intake can be made. [ABSTRACT FROM AUTHOR]

A study was conducted to evaluate in vitro efficacy of seaweed (Sargassum myriocystum and Sargassum wightii) and seagrass (Cymodocea serrulata and Syringodium isoetifolium) extract against the mycelial growth of Macrophomina phaseolina at different concentrations of 5, 10, 15 and 20% along with control by poison food technique. The result revealed that, the extract of S. wightii (20%) exhibited the highest suppression of mycelial growth (10, 25 and 38 mm) at 24, 48 and 72 h after incubation. Among the antagonists tested against Macrophomina phaseolina, the fungal Trichoderma viride was found to be the most effective in reducing mycelial growth than the bacterial antagonist Pseudomonas fluorescens. Both the antagonistic fungi and bacteria have compatibility with seaweed and seagrass extracts in the concentrations. [ABSTRACT FROM AUTHOR]

Many studies have quantified the ecological impacts of individual foundation species (FS). However, emerging data suggest that FS often co‐occur, potentially inhibiting or facilitating one another, thereby causing indirect, cascading effects on surrounding communities. Furthermore, global warming is accelerating, but little is known about how interactions between co‐occurring FS vary with temperature.Shallow aquatic sedimentary systems are often dominated by three types of FS: slower‐growing clonal angiosperms, faster‐growing solitary seaweeds and shell‐forming filter‐ and deposit‐feeding bivalves. Here, we tested the impacts of one FS on another by analyzing manipulative interaction experiments from 148 papers with a global meta‐analysis.We calculated 1942 (non‐independent) Hedges' g effect sizes, from 11,652 extracted values over performance responses, such as abundances, growth or survival of FS and their associated standard deviations and replication levels. Standard aggregation procedures generated 511 independent Hedges' g that were classified into six types of reciprocal impacts between FS.We found that (i) seaweeds had consistent negative impacts on angiosperms across performance responses, organismal sizes, experimental approaches and ecosystem types; (ii) angiosperms and bivalves generally had positive impacts on each other (e.g. positive effects of angiosperms on bivalves were consistent across organismal sizes and experimental approaches, but angiosperm effect on bivalve growth and bivalve effect on angiosperm abundance were not significant); (iii) bivalves positively affected seaweeds (particularly on growth responses); (iv) there were generally no net effects of seaweeds on bivalves (except for the positive effect on growth) or angiosperms on seaweeds (except for the positive effect on 'other processes') and (v) bivalve interactions with other FS were typically more positive at higher temperatures, but angiosperm‐seaweed interactions were not moderated by temperature.Synthesis. Despite variations in experimental and spatiotemporal conditions, the stronger positive interactions at higher temperatures suggest that facilitation, particularly involving bivalves, may become more important in a future warmer world. Importantly, addressing research gaps, such as the scarcity of FS interaction experiments from tropical and freshwater systems and for less studied species, as well as testing for density‐dependent effects, could better inform aquatic ecosystem conservation and restoration efforts and broaden our knowledge of FS interactions in the Anthropocene. [ABSTRACT FROM AUTHOR]

St. Martin's Reef (SMR) about 14 km west of the St. Martin's Island, Teknaf, Cox's Bazar, Bangladesh was not known during last over 50 years of seaweed researches. Recent six collections made with the assistance of Bangladesh Navy revealed 8 seaweeds species which are Pterocladiella maribagoensis Boo and Geraldino, Hypnea spinella (C. Agardh) Kützing, Peyssonnelia polymorpha (Zanar.) Schmitz, Jania pumila Lam., J. ungulata f. brevior (Yendo) Yendo (Rhodophyta); Caulerpa racemosa var. clavifera (Turner) Bosse, Bryopsis plumosa (Huds.) C. Ag. and Halimeda tuna (Ellis & Solander) Lam. (Chlorophyta). Of these six seaweeds such as Pterocladiella maribagoensis Boo et Geraldino, Hypnea spinella (C. Agardh) Kützing, Jania pumila Lamx., J. ungulata f. brevior (Yendo) Yendo, Bryopsis plumosa (Huds.) C. Ag. and Halimeda tuna (Ellis & Solander) Lam. have been newly recorded and described from the SMR in Bay of Bengal (Bangladesh territory). Presence of Peyssonnelia polymorpha and Bryopsis plumosa in the collections and physical and chemical water environments recorded indicated it as a true newly forming reef. The present illustrated account is however may be considered as base-line information on seaweed flora of the new SMR in the North-east Bangladesh coast. A total of six seaweeds have been newly recorded making the total seaweeds to 216 mostly from the SMI and nearby SMR. [ABSTRACT FROM AUTHOR]

Marine macroalgae are emerging as sustainable and healthy food, and a source of lipids with nutritional and bioactive properties. Nonetheless, the lipidome of macroalgae is little explored compared to other photosynthetic organisms. Most of the literature is devoted to the analysis of fatty acid (FA) from macroalgae, because of they are a source of long‐chain omega‐3 and omega‐6 polyunsaturated FA, which can be used as an alternative to fish oil. However, FA occurs mostly esterified in other lipids, such as polar lipids, that still overlooked. The data published on the study of polar lipids (phospholipids, glycolipids, betaine lipids) pinpoint their remarkable characteristics and bioactive properties which mainly remain unexplored. The lipidome of macroalgae seems to be species‐specific, while some lipid classes appear to be characteristic of phyla. Lipidome plasticity of macroalgae is verified to change under abiotic and biotic factors which may modulate the functionality and add‐value of the biomass. This biochemical plasticity represents an advantage to obtain ingredients for target applications and niche of markets. This review provides an overview on macroalgae lipidome characterization, addressing analysis workflow based on liquid chromatography coupled to mass spectrometry, and discussing the bioactive properties and biotechnological applications of macroalga lipids. Practical Applications: The current state of the art on marine macroalgae lipidomics is reviewed, including the lipid characterization using modern liquid chromatography‐mass spectrometry, the distribution of polar lipids by macroalgae species and phylum, their bioactive properties, and potential biotechnological applications. In a time of increasing awareness of sustainably produced marine resources, the lipids from macroalgae are still underexplored. This review provides information for smart valorization of macroalgae as source of add‐value lipids contributing to the development of blue bioeconomy. [ABSTRACT FROM AUTHOR]

Biorefinery, hydrocolloid industry, seaweed processor, seaweeds, waste valorization Keywords: biorefinery; hydrocolloid industry; seaweed processor; seaweeds; waste valorization EN biorefinery hydrocolloid industry seaweed processor seaweeds waste valorization 1020 1027 8 06/06/23 20230601 NES 230601 INTRODUCTION An increasing demand for carbon-neutral, sustainable alternatives to petrochemical products has invigorated interests around the industrial utilization of biomass and biomass-derived feedstocks.[[1]] In addition, a closed-loop system in which feed materials and energy are recovered or recycled has been identified as a key framework for facilitating the transition to eco-effective industrial systems, thereby encouraging its widespread adoption across industrial sectors based on different bioresources.[[1]] Seaweeds have been a key subject of extensive investigations with respect to facilitating circular biomass-based economy because of its clear advantages over terrestrial crops.[[2]] In particular, the cultivation potential of seaweeds in large-scale offshore farms has promoted them as a promising candidate for carbon capture with minimal external nutrient requirements and almost zero competition for agricultural land.[[3]] Moreover, seaweeds themselves have considerable economic value not just because of their fast growth rates, but due to their unique chemical composition.[5] As an alternative feedstock to ligno-cellulosic biomass,[3] seaweeds contain a suite of functional ingredients, including polysaccharides, proteins, lipids and polyphenols. Although the availability of each of these waste materials depends on the species and quality of raw seaweed materials being processed and the choice of processing conditions at different facilities,[15] literature survey and personal communications with industry experts indicated that these waste materials could be more than 50% of raw seaweed biomass. [Extracted from the article]

The essay addresses the reasons why fashion design is manifesting an increasing interest in the marine environment as a context where to identify new sustainable materials for fashion, focusing on the particular case of seaweeds. Through the analysis of some significant international case studies, the recent applications of a variety of biomaterials derived from algae are observed. This phenomenon is interpreted not only as a response to the emergencies of innovation and sustainability in fashion design, but also confirms the framework of a new materialism according to a posthuman perspective. Water shifts from being perceived as a natural element exploited and polluted by fashion into a place of making kin between human and non-human through the use of seaweeds. This is possible thanks to the collaboration of design, chemistry, biology and technology, that are orchestrated to redefine the expressive codes of contemporary fashion within a multispecies landscape. [ABSTRACT FROM AUTHOR]

Brown seaweed is rich in phenolic compounds and has established health benefits. However, the phenolics present in Australian beach-cast seaweed are still unclear. This study investigated the effect of ultrasonication and conventional methodologies using four different solvents on free and bound phenolics of freeze-dried brown seaweed species obtained from the southeast Australian shoreline. The phenolic content and their antioxidant potential were determined using in vitro assays followed by identification and characterization by LC-ESI-QTOF-MS/MS and quantified by HPLC-PDA. The Cystophora sp. displayed high total phenolic content (TPC) and phlorotannin content (FDA) when extracted using 70% ethanol (ultrasonication method). Cystophora sp., also exhibited strong antioxidant potential in various assays, such as DPPH, ABTS, and FRAP in 70% acetone through ultrasonication. TAC is highly correlated to FRAP, ABTS, and RPA (p < 0.05) in both extraction methodologies. LC-ESI-QTOF-MS/MS analysis identified 94 and 104 compounds in ultrasound and conventional methodologies, respectively. HPLC-PDA quantification showed phenolic acids to be higher for samples extracted using the ultrasonication methodology. Our findings could facilitate the development of nutraceuticals, pharmaceuticals, and functional foods from beach-cast seaweed. [ABSTRACT FROM AUTHOR]

Seaweed associated bacteria can be exploited for sustainable production and conservation of seaweeds, although limited information exists in several coastal waters in West Africa. Here, the diversity and abundance of bacteria on five seaweeds, Sargassum vulgare, Padina durvillaei, Hydropuntia dentata, Hypnea musciformis and Ulva fasciata, and surrounding seawaters across five coastal sites in the Central and Western regions of Ghana were investigated. Biochemical tests and MALDIâ€"TOF identification system were used to determine the bacteria diversity and abundance on the seaweeds and seawater. A total of 530 bacterial isolates, belonging to 28 species (and mostly Proteobacteria and Firmicutes) were identified. A higher diversity of bacteria species was found associated with the seaweeds (83%) than in seawater (17%). Bacterial composition was similar among taxonomically-related seaweeds. The brown (S. vulgare) and red (H. musciformis) seaweeds recorded the most and least diverse bacterial assemblage, respectively. Seasonally, bacterial diversity and abundance were marginally higher in the wet season. The study provides important baseline information on the spatial, temporal and taxonomic distribution of bacteria associated with commercially valuable seaweed species in the coastal areas of Ghana. The results are also important for the sustainable exploitation and conservation of these important macroalgae in Ghana and elsewhere. [ABSTRACT FROM AUTHOR]

Macroalgae exhibit beneficial bioactivities for human health. Thus, the aim of the present study was to examine the antioxidant and anticancer potential of 14 macroalgae species' extracts, namely, Gigartina pistillata, Gigartina teedei, Gracilaria gracilis, Gracilaria sp., Gracilaria bursa pastoris, Colpomenia sinuosa, Cystoseira amentacea, Cystoseira barbata, Cystoseira compressa, Sargassum vulgare, Padina pavonica, Codium fragile, Ulva intestinalis, and Ulva rigida, from the Aegean Sea, Greece. The antioxidant activity was assessed using DPPH, ABTS•+, •OH, and O2•− radicals' scavenging assays, reducing power (RP), and protection from ROO•-induced DNA plasmid damage assays. Moreover, macroalgae extracts' total polyphenol contents (TPCs) were assessed. Extracts' inhibition against liver HepG2 cancer cell growth was assessed using the XTT assay. The results showed that G. teedei extract's IC50 was the lowest in DPPH (0.31 ± 0.006 mg/mL), ABTS•+ (0.02 ± 0.001 mg/mL), •OH (0.10 ± 0.007 mg/mL), O2•− (0.05 ± 0.003 mg/mL), and DNA plasmid breakage (0.038 ± 0.002 mg/mL) and exhibited the highest RP (RP0.5AU 0.24 ± 0.019 mg/mL) and TPC (12.53 ± 0.88 mg GAE/g dw). There was also a significant correlation between antioxidant activity and TPC. P. pavonica (IC50 0.93 ± 0.006 mg/mL) exhibited the highest inhibition against HepG2 cell growth. Conclusively, some of the tested extracts exhibited significant chemopreventive properties, and so they may be used for food products. [ABSTRACT FROM AUTHOR]

The ecosystem services can be divided using two major classification systems, the Millennium Ecosystem Assessment (MEA) and the Common International Classification of Ecosystem Services (CICES). In the MEA system, the ecosystem services are divided into four major service clusters: supporting, provisioning, regulating, and cultural. On the other hand, the CICES system regards the "MEA supporting services" as organism natural function (and not an ecosystem service). Thus, this function is the basis for all the three CICES ecosystem services (provisioning, regulating, and cultural) provided by one organism. These ecosystem services can be analyzed for the type of habitat, fauna or flora. Seaweeds, or marine macroalgae, are one of the key organisms in estuarine and seawater habitats ecosystems, which currently is of extreme importance due to the climate changes and the blue–green economy. Seaweeds and humankind have been interlinked from the beginning, mainly as a food source, fibers, biochemicals, natural medicine, ornamental resources, art inspiration, and esthetic values in several coastal communities. Moreover, currently they are being studied as green carbon, carbon sequestration, and as a possible source for the biomedical and pharmaceutical areas. This review is a concise review of all ecological services provided by seaweeds and their impact in the human life and maintenance of the ecosystem status quo. The future of seaweeds use is also approached, regarding the promotion of seaweed ecological services and its dangers in the future. [ABSTRACT FROM AUTHOR]

Although several enzymatic approaches have been applied with this intent, the sequential use of enzymes covering both cellulolytic and proteolytic activity has never been performed in seaweeds. Sequential use of these enzymes improved the overall extraction yield by up to 160%, 30% and 80% in the different seaweeds when compared to the control condition (water extraction), use of a carbohydrases' cocktail alone and use of proteases alone, respectively. Regarding the proximate composition of extracts, it proved to be an efficient approach for the solubilization of carbohydrates (up to 28% in G. vermiculophylla, 66% in P. dioica, 77% in U. rigida and 35% in F. vesiculosus) and protein (up to 55% in G. vermiculophylla, 47% in P. dioica, 52% in U. rigida and 42% in F. uesiculosus). For all biomasses, the combination of enzymes induced a significant increase in antioxidant activity, not only by the increase of phenolic compounds but also by the hydrolysis of protein to peptides. Moreover, extracts from red seaweeds displayed prebiotic activity which can be ascribed to their increased content in oligosaccharides and protein/peptides. Overall, the sequential use of enzymes with different activities demonstrated to be an efficient approach for extracting functional fractions to be used as functional ingredients to improve the nutritional value (e.g. in proteins) and/or to include antioxidant and prebiotic features in the food product. [ABSTRACT FROM AUTHOR]

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Tasmania is an island state in south-eastern Australia that has a long and rich history of seaweed use, research, and development. It is a cool-temperate system with 750 macroalgal species currently described. Tasmanian Aboriginal peoples have lived on this land for at least 40,000 years utilising seaweed as food, shelter, water carriers and medicine, as well as for ceremonial reasons. Modern taxonomic investigations began with French naturalist Jacques-Julien Houtou de La Billardière in 1791, and there are 184 type specimens of seaweeds originating from Tasmania. Ecological and physiological studies of seaweed in Tasmania have focussed on the dominant large brown seaweeds (Laminariales and Fucales) and have contributed significantly to the global understanding of these systems, particularly related to community resilience, seaweed-urchin interactions, their habitat-forming role for other species, responses to global change, and restoration of lost habitat. Ocean warming and changing oceanography have caused a 95% decline in surface canopy cover of Macrocystis pyrifera in eastern Tasmania since the 1950s and led to a focus on restoring these lost forests. Tasmanian seaweed communities have a uniquely high proportion (up to ∼90%) of seaweeds that rely solely on CO2 for photosynthesis, which has implications for responses to ocean acidification. Tasmania has industries that use brown seaweeds for fucoidan extraction and beach-cast harvest for alginates, fertilisers, and feeds for agriculture. New aquaculture initiatives include integrated multi-trophic aquaculture, offshore kelp mariculture and Asparagopsis cultivation for bioactive products to reduce methane emissions in ruminants, as and the development of unexploited species including Caulerpa spp. for food. [ABSTRACT FROM AUTHOR]

The development and recycling of biomass production can partly solve issues of energy, climate change, population growth, food and feed shortages, and environmental pollution. For instance, the use of seaweeds as feedstocks can reduce our reliance on fossil fuel resources, ensure the synthesis of cost-effective and eco-friendly products and biofuels, and develop sustainable biorefinery processes. Nonetheless, seaweeds use in several biorefineries is still in the infancy stage compared to terrestrial plants-based lignocellulosic biomass. Therefore, here we review seaweed biorefineries with focus on seaweed production, economical benefits, and seaweed use as feedstock for anaerobic digestion, biochar, bioplastics, crop health, food, livestock feed, pharmaceuticals and cosmetics. Globally, seaweeds could sequester between 61 and 268 megatonnes of carbon per year, with an average of 173 megatonnes. Nearly 90% of carbon is sequestered by exporting biomass to deep water, while the remaining 10% is buried in coastal sediments. 500 gigatonnes of seaweeds could replace nearly 40% of the current soy protein production. Seaweeds contain valuable bioactive molecules that could be applied as antimicrobial, antioxidant, antiviral, antifungal, anticancer, contraceptive, anti-inflammatory, anti-coagulants, and in other cosmetics and skincare products. [ABSTRACT FROM AUTHOR]

The exploration of bioactive phytochemical quantities of two underutilized Sri Lankan seaweeds Ulva lactuca (UL) and Ulva fasciata (UF) revealed significant phenolic, flavonoid, ulvan, carotenoid, chlorophyll, tannin, saponin, alkaloid contents, and DPPH radical scavenging activities. To evaluate their application in developing seaweed incorporated cereal-based functional snacks, wheat crackers were formulated using 0% (control), 2%, and 4% seaweed powder as a flour replacement. Developed seaweed incorporated crackers had elevated sensory acceptability, protein, and ash contents and DPPH radical scavenging activities, confirming the capacity of UL and UF seaweed utilization in producing potentially functional snacks with improved sensory and nutritional attributes. [ABSTRACT FROM AUTHOR]

Seaweeds have a variety of biological activities, and their aromatic characteristics could play an important role in consumer acceptance. Here, changes in aroma compounds were monitored during microbial fermentation, and those most likely to affect sensory perception were identified. Ulva sp. and Laminaria sp. were fermented and generally recognized as safe microorganisms, and the profile of volatile compounds in the fermented seaweeds was investigated using headspace solid-phase microextraction with gas chromatography–mass spectrometry. Volatile compounds, including ketones, aldehydes, alcohols, and acids, were identified during seaweed fermentation. Compared with lactic acid bacteria fermentation, Bacillus subtilis fermentation could enhance the total ketone amount in seaweeds. Saccharomyces cerevisiae fermentation could also enhance the alcohol content in seaweeds. Principal component analysis of volatile compounds revealed that fermenting seaweeds with B. subtilis or S. cerevisiae could reduce aldehyde contents and boost ketone and alcohol contents, respectively, as expected. The odor of the fermented seaweeds was described by using GC–olfactometry, and B. subtilis and S. cerevisiae fermentations could enhance pleasant odors and reduce unpleasant odors. These results can support the capability of fermentation to improve the aromatic profile of seaweeds. [ABSTRACT FROM AUTHOR]

Seaweeds could be alternative feedstuffs for ruminants, but their utilization in practical feeding is difficult because they deteriorate rapidly. We investigated the possibility of preserving Saccharina latissima and Porphyra umbilicalis in multinutrient blocks (MB), which is a cost-effective preservation method for high-moisture feeds. Three different MB were prepared: without seaweed (control; CMB), with 25% of fresh S. latissima (SLMB), and with 36% of fresh P. umbilicalis (PUMB). Both seaweeds and MB were fermented in vitro with ruminal fluid from sheep. The nitrogen and fiber content of P. umbilicalis was 4- and 4.5-fold greater, respectively, than in S. latissima, but P. umbilicalis produced less gas than S. latissima. Both CMB and PUMB had similar in vitro dry matter degradability (65.8 and 65.1%, respectively), but SLMB had lower values (p < 0.05; 58.2%). There were no differences among MB in methane and total VFA production, but the VFA pattern was shifted to acetate in SLMB and to butyrate in PUMB. The results indicate that multinutrient blocks could be a feasible option to preserve and store seaweeds for ruminant feeding without compromising ruminal fermentation, but in vivo studies are needed to assess the effects on intake and animal performance. [ABSTRACT FROM AUTHOR]

The marine environment presents itself as a treasure chest, full of a vast diversity of organisms yet to be explored. Among these organisms, macroalgae stand out as a major source of natural products due to their nature as primary producers and relevance in the sustainability of marine ecosystems. Sulfated polysaccharides (SPs) are a group of polymers biosynthesized by macroalgae, making up part of their cell wall composition. Such compounds are characterized by the presence of sulfate groups and a great structural diversity among the different classes of macroalgae, providing interesting biotechnological and therapeutical applications. However, due to the high complexity of these macromolecules, their chemical characterization is a huge challenge, driving the use of complementary physicochemical techniques to achieve an accurate structural elucidation. This review compiles the reports (2016–2021) of state-of-the-art methodologies used in the chemical characterization of macroalgae SPs aiming to provide, in a simple way, a key tool for researchers focused on the structural elucidation of these important marine macromolecules. [ABSTRACT FROM AUTHOR]

In the last two decades, major taxonomic modifications have taken place on marine macroalgae with important changes at the genera level and discovery of cryptic species worldwide. These updates have an important role by serving as a baseline for future ecological interpretations related to on-going climate changes in the marine environment. Hence, this study aimed to elaborate a comprehensive and revised checklist of seaweeds and seagrasses reported in the literature over the years for Syrian Mediterranean Sea shorelines. It was found that the marine flora is quite diverse with a recounted total of 290 species of which 52 are Chlorophyta, 178 Rhodophyta and 60 Ochrophyta (Phaeophyceae). The Syrian shores also host five marine angiosperms (seagrasses), even though Zostera marina Linnaeus has been unaccounted for in recent years. This study will further contribute to a better understanding of seaweed distribution within the Levant basin. [ABSTRACT FROM AUTHOR]