Seaweed nutraceuticals and their therapeutic role in disease prevention

The potential mechanisms of Macrocystis pyrifera polysaccharides mitigating type 2 diabetes in rats

Our previous studies have proved that the anti-digestive polysaccharide from Macrocystis pyrifera possesses potential hypoglycemic and lipid-lowering activities; however, its potential mechanisms for improving diabetes have not been elucidated. The current study was aimed to determine the anti-diabetic effects and possible mechanisms of Macrocystis pyrifera polysaccharides (MPP) in diabetic rats. After 8-week MPP treatment, the serum profiles, gut bacteria composition and relative gene expressions of rats were determined. MPP administration effectively ameliorated the diabetic symptoms, dyslipidemia, liver and kidney damage, oxidative stress and chronic inflammation in diabetic rats. In addition, MPP treatment could also notably improve the microbial dysbiosis by increasing the beneficial bacteria and decreasing a bacterial pathogen in the diabetic rats. The RT-qPCR analysis indicated that MPP intervention significantly up-regulated the IRS/PI3K/AKT signaling pathway and down-regulated the relative expressions of glucose-6-phosphatase (G-6-Pase), phosphoenolpyruvate carboxykinase (PEPCK), acetyl-CoA carboxylase (ACC), hydroxymethylglutaryl CoA reductase (HMGCR) and sterol regulatory element binding protein 1c (SREBP-1c) in diabetic rats. These results demonstrated that MPP had the potential to be exploited as functional foods or pharmaceutical supplements for preventing and treating diabetes.

Optimisation of Vitamin B12 Extraction from Green Edible Seaweed (Ulva lactuca) by Applying the Central Composite Design

Vitamin B12, only found naturally in animal-based foods, is essential for brain functions and various chemical reactions in the human body. Insufficient vitamin B12 leads to vitamin B12 deficiency, common among strict vegetarians due to their limited intake of animal-based foods. Nevertheless, extensive studies have demonstrated that macroalgae, specifically the Ulva lactuca species, are rich in vitamin B12 and could be further exploited in future dietary applications. In the current study, the ideal extraction method of vitamin B12 from dried U. lactuca was developed and optimised to achieve the maximum vitamin B12 yield. The effects of several extraction parameters, including the solvent-to-solvent, methanol:water (MeOH:H₂O), and solute-to-solvent ratios, and pH on the total vitamin B12 content were analysed through a two-level factorial and central composite design. The highest vitamin B12 content, particularly cyanocobalamin (CN-Cbl), was recovered through the ultrasonic-assisted extraction (UAE) of oven-dried U. lactuca at 3 g:60 mL of solute-to-solvent and 25:75% of MeOH to H₂O ratios at pH 4. The extraction of CN-Cbl from oven-dried U. lactuca that employed the UAE method has elevated CN-Cbl content recovery compared to other extraction methods.

Modulation of T Cell Responses by Fucoidan to Inhibit Osteogenesis

Fucoidan has sparked considerable interest in biomedical applications because of its inherent (bio)physicochemical characteristics, particularly immunomodulatory effects on macrophages, neutrophils, and natural killer cells. However, the effect of fucoidan on T cells and the following regulatory interaction on cellular function has not been reported. In this work, the effect of sterile fucoidan on the T-cell response and the subsequent modulation of osteogenesis is investigated. The physicochemical features of fucoidan treated by high-temperature autoclave sterilization are characterized by UV–visible spectroscopy, X-ray diffraction, Fourier transform infrared and nuclear magnetic resonance analysis. It is demonstrated that high-temperature autoclave treatment resulted in fucoidan depolymerization, with no change in its key bioactive groups. Further, sterile fucoidan promotes T cells proliferation and the proportion of differentiated T cells decreases with increasing concentration of fucoidan. In addition, the supernatant of T cells co-cultured with fucoidan greatly suppresses the osteogenic differentiation of MC3T3-E1 by downregulating the formation of alkaline phosphatase and calcium nodule compared with fucoidan. Therefore, our work offers new insight into the fucoidan-mediated T cell and osteoblast interplay.

Bioconversion of the Brown Tunisian Seaweed Halopteris scoparia: Application to Energy

The brown Tunisian seaweed Halopteris scoparia was used as a feedstock for producing renewable bioethanol, biogas, and biodiesel to demonstrate the proof of concept for the North African energy sector. A quantitative and qualitative quantification of H. scoparia composition using different colorimetric methods was completed to highlight its bioconversion potential. These substrate inputs were subjected to anaerobic fermentation by Saccharomyces cerevisiae to produce bioethanol. The materials were also used to generate bio-hydrogen and volatile fatty acids during dark fermentation by a bacterial consortium and using the oleaginous yeast Yarrowia lipolytica. The lipids were extracted and trans-esterified to Fatty Acid Methyl Esters (FAMEs), and their profiles were then analyzed with gas chromatography (GC). A significant ratio of the bioethanol, e.g., 0.35 g ethanol/g DW substrate, was produced without pretreatment, consistent with the theoretical Gay-Lussac yield. The production of the biohydrogen and lipids were up to 1.3 mL H2/g DW substrate and 0.04 g/g DW substrate, respectively, from the raw biomass. These results were higher than those reported for other well-studied seaweeds such as L. japonica. Overall, this work contributes to the current investigations in Tunisia for producing alternative energies from algae and finding new solutions to the current energy situation and environmental challenges in Maghreb.

Seaweed and Iodine Intakes and SLC5A5 rs77277498 in Relation to Thyroid Cancer

BACKGRUOUND

This study aims to elucidate the associations among dietary seaweed (gim and miyeok/dashima) and iodine intakes, the rs77277498 polymorphism of the SLC5A5 gene codifying the sodium/iodine symporter, and thyroid cancer risk in a Korean population.

METHODS

We conducted a case-control study of 117 thyroid cancer cases and 173 controls who participated in the Cancer Screenee Cohort between 2002 and 2014 at the National Cancer Center, Korea. The amount of seaweed and iodine consumption (g/day) was estimated using the residual energy adjustment method. We calculated odds ratios (ORs) and their 95% confidence intervals (CIs) using a multivariable logistic regression model for the separate and combined effect of dietary iodine-based intake and SLC5A5 polymorphism (rs77277498, C>G) on thyroid cancer.

RESULTS

Dietary gim and iodine intakes were inversely associated with thyroid cancer, with ORs of 0.50 (95% CI, 0.30 to 0.83) and 0.57 (95% CI, 0.35 to 0.95), respectively, whereas the associations for dietary miyeok/dashima and total seaweed intakes were not significant. However, compared with individuals carrying the C/C genotype of the rs77277498 polymorphism with a low intake of all dietary factors, those carrying the G allele with a high intake had a lower risk of thyroid cancer, with ORs of 0.25 (95% CI, 0.10 to 0.56), 0.31 (95% CI, 0.12 to 0.77), 0.26 (95% CI, 0.10 to 0.62), and 0.30 (95% CI, 0.12 to 0.73) for the consumption of gim, miyeok/dashima, total seaweed, and iodine, respectively.

CONCLUSION

In summary, our results supported the evidence of the protective effects of dietary gim and iodine intake against thyroid cancer risk, and this association can be strengthened by SLC5A5 rs77277498 genotypes.

An insight to the therapeutic potential of algae-derived sulfated polysaccharides and polyunsaturated fatty acids: Focusing on the COVID-19

Covid-19 pandemic severely affected human health worldwide. The rapidly increasing COVID-19 cases and successive mutations of the virus have made it a major challenge for scientists to find the best and efficient drug/vaccine/strategy to counteract the virus pathogenesis. As a result of research in scientific databases, regulating the immune system and its responses with nutrients and nutritional interventions is the most critical solution to prevent and combat this infection. Also, modulating other organs such as the intestine with these compounds can lead to the vaccines' effectiveness. Marine resources, mainly algae, are rich sources of nutrients and bioactive compounds with known immunomodulatory properties and the gut microbiome regulations. According to the purpose of the review, algae-derived bioactive compounds with immunomodulatory activities, sulfated polysaccharides, and polyunsaturated fatty acids have a good effect on the immune system. In addition, they have probiotic/prebiotic properties in the intestine and modulate the gut microbiomes; therefore, they can increase the effectiveness of vaccines produced. Thus, they with respectable safety, immune regulation, and modulation of microbiota have potential therapeutic against infections, especially COVID-19. They can also be employed as promising candidates for the prevention and treatment of viral infections, such as COVID-19.

Biological Potential, Gastrointestinal Digestion, Absorption, and Bioavailability of Algae-Derived Compounds with Neuroprotective Activity: A Comprehensive Review

Currently, there is no known cure for neurodegenerative disease. However, the available therapies aim to manage some of the symptoms of the disease. Human neurodegenerative diseases are a heterogeneous group of illnesses characterized by progressive loss of neuronal cells and nervous system dysfunction related to several mechanisms such as protein aggregation, neuroinflammation, oxidative stress, and neurotransmission dysfunction. Neuroprotective compounds are essential in the prevention and management of neurodegenerative diseases. This review will focus on the neurodegeneration mechanisms and the compounds (proteins, polyunsaturated fatty acids (PUFAs), polysaccharides, carotenoids, phycobiliproteins, phenolic compounds, among others) present in seaweeds that have shown in vivo and in vitro neuroprotective activity. Additionally, it will cover the recent findings on the neuroprotective effects of bioactive compounds from macroalgae, with a focus on their biological potential and possible mechanism of action, including microbiota modulation. Furthermore, gastrointestinal digestion, absorption, and bioavailability will be discussed. Moreover, the clinical trials using seaweed-based drugs or extracts to treat neurodegenerative disorders will be presented, showing the real potential and limitations that a specific metabolite or extract may have as a new therapeutic agent considering the recent approval of a seaweed-based drug to treat Alzheimer’s disease.

Phytochemical and Potential Properties of Seaweeds and Their Recent Applications: A Review

Since ancient times, seaweeds have been employed as source of highly bioactive secondary metabolites that could act as key medicinal components. Furthermore, research into the biological activity of certain seaweed compounds has progressed significantly, with an emphasis on their composition and application for human and animal nutrition. Seaweeds have many uses: they are consumed as fodder, and have been used in medicines, cosmetics, energy, fertilizers, and industrial agar and alginate biosynthesis. The beneficial effects of seaweed are mostly due to the presence of minerals, vitamins, phenols, polysaccharides, and sterols, as well as several other bioactive compounds. These compounds seem to have antioxidant, anti-inflammatory, anti-cancer, antimicrobial, and anti-diabetic activities. Recent advances and limitations for seaweed bioactive as a nutraceutical in terms of bioavailability are explored in order to better comprehend their therapeutic development. To further understand the mechanism of action of seaweed chemicals, more research is needed as is an investigation into their potential usage in pharmaceutical companies and other applications, with the ultimate objective of developing sustainable and healthier products. The objective of this review is to collect information about the role of seaweeds on nutritional, pharmacological, industrial, and biochemical applications, as well as their impact on human health.

The Influence of Abiotic Factors on the Induction of Seaweed Callus

Seaweeds are a major source of functional foods, nutraceuticals, and pharmaceuticals. Seaweed can be sustainably harvested through callus culture, which yields homogenous cells and bioproducts under controlled conditions. Callus induction is a crucial early step in callus culture and is influenced by several abiotic factors. This review aims to discuss the influence of abiotic factors on callus induction in seaweeds, a prerequisite for the application and development of seaweed callus culture. We used three online databases (Springer, Science Direct, and Wiley) to search for the literature on seaweed callus induction published between 1987 and 2020. Thirty-three articles for review were identified and analyzed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The analysis covers 56 seaweed species (3% Chlorophyta, 44% Phaeophyta, and 53% Rhodophyta) under various abiotic treatments, including light irradiance (23%), temperature (15%), media type (21%), plant growth regulators (26%), gelling conditions (9%), and other factors (6%). The information on these abiotic factors is intended to be a practical reference and to foster the further study of the callus culture of seaweed. More studies are needed to determine how to maintain and increase callus mass in suspension culture for the industrial production of seaweed and its metabolites.

Comprehensive Lipidomic Analysis of Three Edible Brown Seaweeds Based on Reversed-Phase Liquid Chromatography Coupled with Quadrupole Time-of-Flight Mass Spectrometry

A comprehensive lipidomic analysis was performed onto three edible brown seaweeds, namely Laminaria japonica, Undaria pinnatifida, and Scagassum natans, using reversed-phase liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (RPLC-Q-TOF-MS/MS). In total, 675 lipid molecules, including glycolipids (GLs), phospholipids, sphingolipids (SLs), betaine lipids, and glycerolipids, were identified and semiquantified. With the exception of the high content of diacylglycerols found in L. japonica (54.6% of total lipids), GLs were the dominant component in the three brown seaweeds (27.7-56.7% of total lipids), containing a high proportion of eicosapentaenoic acid. Interestingly, SLs represented by ceramide and hexosylceramide containing phytosphingosine and α-hydroxy fatty acid structures were detected in the three brown seaweeds. A large number of acylated GLs were identified and reported for the first time in these seaweeds, including acylated monogalactosyldiacylglycerol and acylated digalactosyldiacylglycerol containing nonoxidized fatty acids. The bioactive lipids identified herein could be considered potential biomarkers for identifying these seaweeds, evaluating their nutritional value and further promoting their utilization.

Assessing the Environmental and Economic Sustainability of Functional Food Ingredient Production Process

Development and application of novel technologies in food processing is vital for ensuring the availability of adequate, safe, and convenient food with the desired quality and functional properties. Environmental and economic sustainability of technologies is essential prior to their application in the food processing sector. The objective of this research is to determine the environmental and economic feasibility of ultrasound-assisted extraction (UAE) for recovering functional food ingredients from seaweed. Experimental data is used to conduct a life cycle assessment (LCA) to investigate the environmental performance with a functional unit (FU) of obtaining 1 g of extracted polyphenols, measured as gallic acid equivalents (mg GAE)/g seaweed. A life cycle impact assessment is performed with ReCiPe 2016 at midpoint. The cost of manufacturing (COM) of phenolic-rich extracts (as functional ingredient, bioactive, or nutraceutical) is estimated using time-driven activity-based costing (TDABC). The environmental profile findings show that across all categories, the UAE has considerably lower impacts than the conventional method, with electricity as the most important impact contributor, followed by solvent production. An economic assessment estimates the COM over a one-year period at a large scale using the UAE to be EUR 1,200,304, EUR 2,368,440, and EUR 4,623,290 for extraction vessel capacities of 0.05, 0.1, and 0.15 m3, respectively. Raw materials (including the type of raw material) and operational labour costs are the primary contributors to the COM. The findings thus present evidence to support the adoption of an environmentally and economically viable technology for functional ingredient production.

Macroalgal Proteins: A Review

Population growth is the driving change in the search for new, alternative sources of protein. Macroalgae (otherwise known as seaweeds) do not compete with other food sources for space and resources as they can be sustainably cultivated without the need for arable land. Macroalgae are significantly rich in protein and amino acid content compared to other plant-derived proteins. Herein, physical and chemical protein extraction methods as well as novel techniques including enzyme hydrolysis, microwave-assisted extraction and ultrasound sonication are discussed as strategies for protein extraction with this resource. The generation of high-value, economically important ingredients such as bioactive peptides is explored as well as the application of macroalgal proteins in human foods and animal feed. These bioactive peptides that have been shown to inhibit enzymes such as renin, angiotensin-I-converting enzyme (ACE-1), cyclooxygenases (COX), α-amylase and α-glucosidase associated with hypertensive, diabetic, and inflammation-related activities are explored. This paper discusses the significant uses of seaweeds, which range from utilising their anthelmintic and anti-methane properties in feed additives, to food techno-functional ingredients in the formulation of human foods such as ice creams, to utilising their health beneficial ingredients to reduce high blood pressure and prevent inflammation. This information was collated following a review of 206 publications on the use of seaweeds as foods and feeds and processing methods to extract seaweed proteins.

Present and Future of Seaweed Cultivation and Its Applications in Colombia

Colombia has a diverse range of marine ecosystems in the coastal and insular areas of the Caribbean Sea and the Pacific Ocean. Seaweed research has focused mainly on the identification and taxonomic distribution of 628 species identified so far, mainly in the Caribbean Sea. Among the most widely cultivated genera of seaweeds in open-sea pilot systems in Colombia are Hydropuntia, Gracilaria, Hypnea, Kappaphycus, and Eucheuma. These genera have shown low yields as a consequence of high tissue fragility, epiphytism, sedimentation, and nitrogen deficiency. In addition, the evaluation of the biological activity of selected seaweed compounds has advanced considerably, focusing on their composition and their use for direct consumption by humans and animals. Despite the diversity of seaweeds, as well as certain technical and scientific advances, Colombia is still lagging behind other countries in seaweed exploitation, both in Latin America and worldwide. This current status raises the need to increase research, technological (agro-tech) appropriation, and the adoption of effective public policies that will boost algal businesses. In addition, seaweed cultivation could support the current blue economy transition in Colombia, which could eventually allow the country to enter the global seaweed market.

Nonpharmacological Treatment Strategies for the Management of Canine Chronic Inflammatory Enteropathy—A Narrative Review

Chronic inflammatory enteropathy (CIE) refers to a heterogeneous group of idiopathic diseases of the dog characterised by persistent gastrointestinal (GI) clinical signs. If conventional dietary treatment alone would be unsuccessful, management of CIE is traditionally attained by the use of pharmaceuticals, such as antibiotics and immunosuppressive drugs. While being rather effective, however, these drugs are endowed with side effects, which may impact negatively on the animal’s quality of life. Therefore, novel, safe and effective therapies for CIE are highly sought after. As gut microbiota imbalances are often associated with GI disorders, a compelling rationale exists for the use of nonpharmacological methods of microbial manipulation in CIE, such as faecal microbiota transplantation and administration of pre-, pro-, syn- and postbiotics. In addition to providing direct health benefits to the host via a gentle modulation of the intestinal microbiota composition and function, these treatments may also possess immunomodulatory and epithelial barrier-enhancing actions. Likewise, intestinal barrier integrity, along with mucosal inflammation, are deemed to be two chief therapeutic targets of mesenchymal stem cells and selected vegetable-derived bioactive compounds. Although pioneering studies have revealed encouraging findings regarding the use of novel treatment agents in CIE, a larger body of research is needed to address fully their mode of action, efficacy and safety.

Therapeutic Potential of Seaweed-Derived Bioactive Compounds for Cardiovascular Disease Treatment

Cardiovascular diseases are closely related to hypertension, type 2 diabetes mellitus, obesity, and hyperlipidemia. Many studies have reported that an unhealthy diet and sedentary lifestyle are critical factors that enhance these diseases. Recently, many bioactive compounds isolated from marine seaweeds have been studied for their benefits in improving human health. In particular, several unique bioactive metabolites such as polyphenols, polysaccharides, peptides, carotene, and sterol are the most effective components responsible for these activities. This review summarizes the current in vitro, in vivo, and clinical studies related to the protective effects of bioactive compounds isolated from seaweeds against cardiovascular disorders, including anti-diabetic, anti-hypertensive, anti-hyperlipidemia, and anti-obesity effects. Therefore, this present review summarizes these concepts and provides a basis for further in-depth research.

Evaluation of Antidiabetic Activity of Sargassum tenerrimum in Streptozotocin-Induced Diabetic Mice

Diabetes mellitus has become the most predominant disease in most of the developing and developed countries. Diabetes could occur at any stage of life for which a change in sedentary life style is the possible solution. Despite the introduction of several medications, to curtail the side effects associated with diabetes mellitus, there is no medication or treatment for complete cure. Existing medications and treatments are targeted to mitigate the intensity of the disease which abruptly could result in organ failure. Rather than the available types of treatments, natural medication is reported to produce commendable results. Extracts of many medicinal plants and seaweeds have been documented to possess anti-diabetic properties. A brown alga, S. tenerrimum, found on the west coast of India, is chosen in this study to analyse the anti-diabetic property of its methanolic extract. This extract was used to treat streptozotocin-induced diabetic mice. An experimental design was framed based on acute toxicity studies to determine the change in blood glucose level, body weight, lipid profile, liver enzymes (SGPT and SGOT) and the renal function markers (urea and creatinine). After 15 days of treatment, an increase in body weight and HDL cholesterol was observed while the total cholesterol, VLDL, LDL, serum triglyceride, SGOT, SGPT, creatinine and urea decreased with 250 mg/Kg.bw of S. tenerrimum methanolic extract in Streptozotocin-induced diabetic mice group. This difference is significant (p<0.05) when compared with a healthy non-diabetic mice group and a treated diabetic mice group. This proves that the methanolic extract of S. tenerrimum possess anti-diabetic property. Further research could explore the active compounds that can be used in the formulation of herbal medicine for diabetes mellitus.

Anticancer Effects of Seaweed-Derived Bioactive Compounds

Cancer remains a major life-threatening disease worldwide. The development of anticancer drugs using natural products obtained from marine organisms has been proposed as an alternative approach. Seaweeds are the mainstay of marine ecosystems; therefore, they are highly enriched with diverse bioactive compounds. In the past decade, a vast number of natural compounds, such as polysaccharides, polyphenols, carotenoids, and terpenoids, have been isolated from seaweeds. Seaweeds have bioactive compounds that show cytotoxicity in various cancer cell lines. These compounds prevent tumor growth by inducing apoptotic cell death and arrest growth by interfering with different kinases and cell cycle pathways. This review discussed the anticancer properties of various bioactive compounds isolated from different types of seaweeds and their therapeutic potential against cancers.

Mechanistic Insight into Apoptotic Induction in Human Rhabdomyosarcoma and Breast Adenocarcinoma Cells by Chnoospora minima: A Sri Lankan Brown Seaweed

The current study determined the cytotoxic and apoptotic potential of the polyphenol-rich methanol extract of Chnoospora minima (C. minima) and its fractions against human breast adenocarcinoma (MCF-7) and rhabdomyosarcoma (RMS) cells. MTT and neutral red assays were used to determine cytotoxicity. The clonogenic assay evaluated the antineoplastic activity, while the apoptotic activity was determined by cellular morphological changes, caspase 3/7 activity, and DNA fragmentation. Morphological alterations in apoptosis were observed by an inverted phase-contrast microscope and Hoechst 33342 staining methods. The total phenolic, flavonoids, alkaloids, and antioxidant activity in the hexane and chloroform fractions were determined, based on their cytotoxic activity. The hexane fraction of C. minima effectively reduced the cell growth that is concentration-dependent in human RMS and MCF-7 cell lines. It also exhibited low cytotoxicity on Vero cells. The characteristic cellular and nuclear apoptotic morphological features were observed. A noticeable caspase 3/7 activation and the fragmented DNA were detected only in the hexane fraction treated RMS cells, whereas MCF-7 cells showed low caspase 3/7 activation due to a lack of caspase 3 and no evidence of having a typical ladder pattern of apoptosis. Further analysis revealed that the hexane fraction-treated RMS cells upregulated the p53 gene twofold (2.72) compared to the p21 (0.77) gene, whereas in the MCF-7 cells, a 2.21-fold upregulation of p53 was observed compared to the p21 (0.64) gene. The hexane fraction exhibited moderate total phenolics, flavonoids, alkaloids content, and antioxidant activity. According to the different antioxidant mechanisms, hexane and chloroform fractions showed the highest antioxidant activities by FRAP and ORAC assays, respectively. GC-MS analysis of hexane fraction revealed the presence of methyl tetradecanoate (38.314%) as the most abundant compound. The study's findings highlighted that the non-polar compounds present in the hexane fraction of C. minima suppressed cell proliferation and induced apoptosis-mediated cell death in RMS and MCF-7 cells, mainly via the activation of the p53 gene. Hence, the isolation of compounds is warranted. However, more studies are required to understand the mechanistic insights of these observations.

Chondracanthus teedei var. lusitanicus: The Nutraceutical Potential of an Unexploited Marine Resource

Presently, there is a high demand for nutritionally enhanced foods, so it is a current challenge to look at new raw food sources that can supplement beneficially the human diet. The nutritional profile and key secondary metabolites of red seaweeds (Rhodophyta) are gaining interest because of this challenge. In this context, the possible use of the red seaweed Chondracanthus teedei var. lusitanicus (Gigartinales) as a novel nutraceutical source was investigated. As a result, we highlight the high mineral content of this seaweed, representing 29.35 g 100 g⁻¹ of its dry weight (DW). Despite the low levels of calcium and phosphorus (0.26 and 0.20 g 100 g⁻¹ DW, respectively), this seaweed is an interesting source of nitrogen and potassium (2.13 and 2.29 g⁻¹ DW, accordingly). Furthermore, the high content of carbohydrates (56.03 g 100 g⁻¹ DW), which acts as dietary fibers, confers a low caloric content of this raw food source. Thus, this study demonstrates that C. teedei var. lusitanicus is in fact an unexploited potential resource with the capability to provide key minerals to the human diet with promising nutraceutical properties.

Seaweed Aquaculture in Indonesia Contributes to Social and Economic Aspects of Livelihoods and Community Wellbeing

Seaweed farming in Indonesia is carried out throughout much of the archipelago and is mainly undertaken by smallholder farmers. Indonesia is the largest global producer of the red seaweeds Kappaphycus and Eucheuma, which are used to produce carrageenan, and is a major producer of Gracilaria, which is used to produce agar. Seaweed farming is attractive to farmers in rural coastal communities because capital and operating costs are low, farming techniques are not technically demanding, labour requirements are relatively low (allowing farmers to engage in other livelihoods), and production cycles are short (30–45 days), providing regular income. Using reported values for seaweed-farming income, we conclude that seaweed farming can, but does not always, lift rural households above the Indonesian poverty line. In addition to direct financial benefits, seaweed farming also contributes to human and social capital within seaweed farming households and communities. Achieving continued economic and social benefits from seaweed farming will require additional policy development, as well as research and development to support improved and more consistent seaweed productivity and improved product quality at the farm level, provision of effective extension and technical support services, and diversification of the existing value chains in order to reduce the impacts of price fluctuations that are associated with limited global commodity chains.

Enhancement of Immune Checkpoint Inhibitor-Mediated Anti-Cancer Immunity by Intranasal Treatment of Ecklonia cava Fucoidan against Metastatic Lung Cancer

Although fucoidan, a well-studied seaweed-extracted polysaccharide, has shown immune stimulatory effects that elicit anticancer immunity, mucosal adjuvant effects via intranasal administration have not been studied. In this study, the effect of Ecklonia cava-extracted fucoidan (ECF) on the induction of anti-cancer immunity in the lung was examined by intranasal administration. In C57BL/6 and BALB/c mice, intranasal administration of ECF promoted the activation of dendritic cells (DCs), natural killer (NK) cells, and T cells in the mediastinal lymph node (mLN). The ECF-induced NK and T cell activation was mediated by DCs. In addition, intranasal injection with ECF enhanced the anti-PD-L1 antibody-mediated anti-cancer activities against B16 melanoma and CT-26 carcinoma tumor growth in the lungs, which were required cytotoxic T lymphocytes and NK cells. Thus, these data demonstrated that ECF functioned as a mucosal adjuvant that enhanced the immunotherapeutic effect of immune checkpoint inhibitors against metastatic lung cancer.

Characterization of alginate extracted from Sargassum latifolium and its use in Chlorella vulgaris growth promotion and riboflavin drug delivery

Alginates derived from macroalgae have been widely used in a variety of applications due to their stability, biodegradability and biocompatibility. Alginate was extracted from Egyptian Sargassum latifolium thallus yielding 17.5% w/w. The chemical composition of S. latifolium is rich in total sugars (41.08%) and uronic acids (47.4%); while, proteins, lipids and sulfates contents are 4.61, 1.13 and 0.09%, respectively. NMR, FTIR and TGA analyses were also performed. Crystallinity index (0.334) indicates alginate semicrystalline nature. Sodium alginate hydrolysate was evaluated as Chlorella vulgaris growth promoter. The highest stimulation (0.7 g/L biomass) was achieved by using 0.3 g/L alginate hydrolysate supplementation. The highest total soluble proteins and total carbohydrates were 179.22 mg/g dry wt and 620.33 mg/g dry wt, respectively. The highest total phenolics content (27.697 mg/g dry wt.), guaiacol peroxidase activity (2.899 µmol min-1 g-1) were recorded also to 0.3 g/L alginate hydrolysate supplementation. Riboflavin-entrapped barium alginate-Arabic gum polymeric matrix (beads) was formulated to achieve 89.15% optimum drug entrapment efficiency (EE%). All formulations exhibited prolonged riboflavin release over 120 min in simulated gastric fluid, followed Higuchi model (R2 = 0.962-0.887) and Korsmeyer-Peppas model with Fickian release (n ranges from 0.204 to 0.3885).

Hypertriglyceridemia treated with Fucus vesiculosus - A case series

Hypertriglyceridemia is an independent risk factor of coronary heart disease (as established through various previously conducted studies) and it's rising incidence is creating a need for the immediate attention of it's management. Instead of focusing on the controversies involving the toxicity caused due to the long-term use of statin therapy in conventional mode of treatment, opting for a safer alternative system of treatment seems important. Five cases of diagnosed HTG, with triglyceride levels above 200 were treated with homoeopathic medicine - Fucus vesiculosus, in mother tincture form. The primary outcome measure was to evaluate the reduction in the blood triglyceride levels. All the five cases showed a reduction in triglyceride levels to normal range within 4 months of starting the treatment with the Fucus vesiculosus mother tincture. Also, it was observed that the borderline cholesterol levels and high LDL levels in 2 cases were found to reduce to normal. Treatment involving Fucus vesiculosus in cases diagnosed with HTG showed significant reduction in triglyceride levels along with other parameters of lipid profile. Further authentication of results with significant sample sizes may be taken up.

Analysis of Minerals and Heavy Metals Using ICP-OES and FTIR Techniques in Two Red Seaweeds (Gymnogongrus griffithsiae and Asparagopsis taxiformis) from Tunisia

In this study, the mineral and heavy metals (arsenic (As), cadmium (Cd), copper (Cu), iron (Fe), mercury (Hg), potassium (K), manganese (Mn), sodium (Na), phosphorus (P), and lead (Pb)) in two red Tunisian seaweeds Gymnogongrus griffithsiae (G. griffithsiae) and Asparagopsis taxiformis (A. taxiformis), were evaluated. Mineral and trace element analyses were achieved using inductively coupled plasma optical emission spectrometry (ICP-OES). Fourier transform infrared (FTIR) spectroscopy was used to predict the major functional groups that would be implicated in the seaweeds mineral uptake. Our results showed that the studied A. taxiformis species had much higher mineral and heavy metal concentrations than G. griffithsiae. Na (200.60 mg/kg) was the most abundant element followed by K (137.84 mg/kg) > P (35.93 mg/kg) for A. taxiformis species. However, only Na (165.23 mg/kg) and P (51.19 mg/kg) were detected in G. griffithsiae alga. As regards heavy and toxic metals, allowable concentrations have been found in both seaweeds. The concentration ranges for the most undesirable heavy metals were as follows: Pb (0.39-0.51 mg/kg), As (0.11-0.40 mg/kg), Cd (0.01-0.02 mg/kg), and Hg (0.00-0.02 mg/kg). According to FTIR analysis, the major functional groups present in the studied seaweeds were carboxyl, hydroxyl, sulfate, and phosphate groups that are considered as excellent binding sites for metal retention.

Characterization of an Agarophyton chilense Oleoresin Containing PPARγ Natural Ligands with Insulin-Sensitizing Effects in a C57Bl/6J Mouse Model of Diet-Induced Obesity and Antioxidant Activity in Caenorhabditis elegans

The biomedical potential of the edible red seaweed Agarophyton chilense (formerly Gracilaria chilensis) has not been explored. Red seaweeds are enriched in polyunsaturated fatty acids and eicosanoids, which are known natural ligands of the PPARγ nuclear receptor. PPARγ is the molecular target of thiazolidinediones (TZDs), drugs used as insulin sensitizers to treat type 2 diabetes mellitus. Medical use of TZDs is limited due to undesired side effects, a problem that has triggered the search for selective PPARγ modulators (SPPARMs) without the TZD side effects. We produced Agarophyton chilense oleoresin (Gracilex®), which induces PPARγ activation without inducing adipocyte differentiation, similar to SPPARMs. In a diet-induced obesity model of male mice, we showed that treatment with Gracilex® improves insulin sensitivity by normalizing altered glucose and insulin parameters. Gracilex® is enriched in palmitic acid, arachidonic acid, oleic acid, and lipophilic antioxidants such as tocopherols and β-carotene. Accordingly, Gracilex® possesses antioxidant activity in vitro and increased antioxidant capacity in vivo in Caenorhabditis elegans. These findings support the idea that Gracilex® represents a good source of natural PPARγ ligands and antioxidants with the potential to mitigate metabolic disorders. Thus, its nutraceutical value in humans warrants further investigation.

The Therapeutic Potential of the Anticancer Activity of Fucoidan: Current Advances and Hurdles

Several types of cancers share cellular and molecular behaviors. Although many chemotherapy drugs have been designed to weaken the defenses of cancer cells, these drugs may also have cytotoxic effects on healthy tissues. Fucoidan, a sulfated fucose-based polysaccharide from brown algae, has gained much attention as an antitumor drug owing to its anticancer effects against multiple cancer types. Among the anticancer mechanisms of fucoidan are cell cycle arrest, apoptosis evocation, and stimulation of cytotoxic natural killer cells and macrophages. Fucoidan also protects against toxicity associated with chemotherapeutic drugs and radiation-induced damage. The synergistic effect of fucoidan with existing anticancer drugs has prompted researchers to explore its therapeutic potential. This review compiles the mechanisms through which fucoidan slows tumor growth, kills cancer cells, and interacts with cancer chemotherapy drugs. The obstacles involved in developing fucoidan as an anticancer agent are also discussed in this review.

A Comprehensive Analysis into the Therapeutic Application of Natural Products as SIRT6 Modulators in Alzheimer's Disease, Aging, Cancer, Inflammation, and Diabetes

Natural products have long been used as drugs to treat a wide array of human diseases. The lead compounds discovered from natural sources are used as novel templates for developing more potent and safer drugs. Natural products produce biological activity by binding with biological macromolecules, since natural products complement the protein-binding sites and natural product-protein interactions are already optimized in nature. Sirtuin 6 (SIRT6) is an NAD+ dependent histone deacetylase enzyme and a unique Sirtuin family member. It plays a crucial role in different molecular pathways linked to DNA repair, tumorigenesis, glycolysis, gluconeogenesis, neurodegeneration, cardiac hypertrophic responses, etc. Thus, it has emerged as an exciting target of several diseases such as cancer, neurodegenerative diseases, aging, diabetes, metabolic disorder, and heart disease. Recent studies have shown that natural compounds can act as modulators of SIRT6. In the current review, a list of natural products, their sources, and their mechanisms of SIRT6 activity modulation has been compiled. The potential application of these naturally occurring SIRT6 modulators in the amelioration of major human diseases such as Alzheimer's disease, aging, diabetes, inflammation, and cancer has also been delineated. Natural products such as isoquercetin, luteolin, and cyanidin act as SIRT6 activators, whereas vitexin, catechin, scutellarin, fucoidan, etc. work as SIRT6 inhibitors. It is noteworthy to mention that quercetin acts as both SIRT6 activator and inhibitor depending on its concentration used. Although none of them were found as highly selective and potent modulators of SIRT6, they could serve as the starting point for developing selective and highly potent scaffolds for SIRT6.

Innovative Ultrasound-Assisted Approaches towards Reduction of Heavy Metals and Iodine in Macroalgal Biomass

The aim of this work was to evaluate the potential of ultrasound (US), alone or in combination with mild heating and/or EDTA towards reduction of As, Cd, I, and Hg content of Laminaria hyperborea. Concentrations of As, Cd, I, and Hg of 56.29, 0.596, 7340, and <0.01 mg kg⁻¹ of dry weight, respectively, were found in L. hyperborea blades. Treatment with US at 50 °C increased approx. 2-fold the amount of As released, although did not affect significantly the content of Cd or I, as compared to control (no US) samples. Reducing the temperature to 8 °C significantly decreased the effect of US, but heating at 80 °C did not cause a significant effect as compared to treatments at 50 °C. On the other hand, treatment with 0.1 N EDTA at 50 °C enhanced the percentage of Cd released by approximately 7-fold, regardless of sonication. In the present work, the combination of US and EDTA at 50 °C for 5 min led to a significant reduction of the As (32%), Cd (52%) and I (31%) content in L. hyperborea, thus improving the product’s safety for consumers.

The Application of Seaweed Polysaccharides and Their Derived Products with Potential for the Treatment of Alzheimer's Disease

Neurodegenerative diseases are among the most widespread diseases affecting humans, and the number of patients is only rising. Seaweed polysaccharide extracts show significant neuroprotective and reparative activities. Seaweed polysaccharides might provide the next big breakthrough in neurodegenerative disease treatment. This paper reviews the applications of seaweed polysaccharides as potential treatments of neurodegenerative diseases. The particular focus is on fucoidan, ulvan, and their derivatives as potential agents to treat Alzheimer's disease. This review provides a critical update on the progress in this important research area.

Traditional Applications of Tannin Rich Extracts Supported by Scientific Data: Chemical Composition, Bioavailability and Bioaccessibility

Tannins are polyphenolic compounds historically utilized in textile and adhesive industries, but also in traditional human and animal medicines or foodstuffs. Since 20th-century, advances in analytical chemistry have allowed disclosure of the chemical nature of these molecules. The chemical profile of extracts obtained from previously selected species was investigated to try to establish a bridge between traditional background and scientific data. The study of the chemical composition of these extracts has permitted us to correlate the presence of tannins and other related molecules with the effectiveness of their apparent uses. The revision of traditional knowledge paired with scientific evidence may provide a supporting background on their use and the basis for developing innovative pharmacology and food applications based on formulations using natural sources of tannins. This traditional-scientific approach can result useful due to the raising consumers' demand for natural products in markets, to which tannin-rich extracts may pose an attractive alternative. Therefore, it is of interest to back traditional applications with accurate data while meeting consumer's acceptance. In this review, several species known to contain high amounts of tannins have been selected as a starting point to establish a correlation between their alleged traditional use, tannins content and composition and potential bioaccessibility.

Brown Algae Potential as a Functional Food against Hypercholesterolemia: Review

Brown algae have been part of the human diet for hundreds of years, however, in recent years, commercial and scientific interest in brown algae has increased due to the growing demand for healthier diet by the world population. Brown algae and its metabolites, such as carotenoids, polysaccharides, phlorotannins, and proteins, have been associated with multiple beneficial health effects for different diseases, such as cardiovascular diseases, one of the main causes of death in Europe. Since high blood cholesterol levels are one of the major cardiovascular risks, this review intends to provide an overview of current knowledge about the anti-hypercholesterolemic effect of different brown algae species and/or their isolated compounds.

Recent Advances in Marine-Based Nutraceuticals and Their Health Benefits

The oceans have been the Earth's most valuable source of food. They have now also become a valuable and versatile source of bioactive compounds. The significance of marine organisms as a natural source of new substances that may contribute to the food sector and the overall health of humans are expanding. This review is an update on the recent studies of functional seafood compounds (chitin and chitosan, pigments from algae, fish lipids and omega-3 fatty acids, essential amino acids and bioactive proteins/peptides, polysaccharides, phenolic compounds, and minerals) focusing on their potential use as nutraceuticals and health benefits.

Anti-Obesity Effects of Sargassum thunbergii via Downregulation of Adipogenesis Gene and Upregulation of Thermogenic Genes in High-Fat Diet-Induced Obese Mice

Obesity is a metabolic disease characterized by an increased risk of type 2 diabetes, hypertension, and cardiovascular disease. We have previously reported that compounds isolated from brown alga, Sargassum thunbergii (ST; Sargassum thunbergii (Mertens ex Roth) Kuntze), inhibit adipogenesis in 3T3-L1 cells. However, the in vivo anti-obesity effects of these compounds have not been previously reported. Therefore, the objective of this study was to determine the effects of ST on weight loss, fat accumulation, as well as risk factors for type 2 diabetes and cardiovascular disease in high-fat diet (HFD)-induced obese mice. ST treatment significantly decreased body weight and fat accumulation in HFD-induced obese mice, while reducing insulin and factors related to cardiovascular diseases (triglyceride and total cholesterol) in serum. ST-induced downregulation of PPARγ in white adipose tissue, and upregulation of the thermogenic genes, UCP-1 and UCP-3, in brown adipose tissue was also observed. In addition, oral administration of ST reduced the occurrence of fatty liver, as well as the amount of white adipose tissue in HFD mice. Cumulatively, these results suggest that ST exerts anti-obesity effects and may serve as a potential anti-obesity therapeutic agent.

Macroalgae-A Sustainable Source of Chemical Compounds with Biological Activities

Nowadays, one of the most important research directions that concerns the scientific world is to exploit the earth's resources in a sustainable way. Considering the increasing interest in finding new sources of bioactive molecules and functional products, many research studies focused their interest on demonstrating the sustainability of exploiting marine macroalgal biomass as feedstock for wastewater treatment and natural fertilizer, conversion into green biofuels, active ingredients in pharmaceutical and nutraceutical products, or even for the production of functional ingredients and integration in the human food chain. The objective of the present paper was to provide an overview on the recent progress in the exploitation of different macroalgae species as a source of bioactive compounds, mainly emphasizing the latter published data regarding their potential bioactivities, health benefits, and industrial applications.

Fucosterol Suppresses the Progression of Human Ovarian Cancer by Inducing Mitochondrial Dysfunction and Endoplasmic Reticulum Stress

Ovarian cancer is difficult to diagnose early and has high rates of relapse and mortality. Therefore, the treatment of ovarian cancer needs to be improved. Recently, several studies have been conducted in an attempt to develop anticancer drugs from naturally derived ingredients. Compared to traditional chemotherapy, natural compounds can overcome drug resistance with lower side effects. Fucosterol, a phytosterol present in brown algae, reportedly possesses many bioactive effects, including anticancer properties. However, the anticancer effects of fucosterol in ovarian cancer remain unexplored. Therefore, we investigated the effects of fucosterol on progression in human ovarian cancer cells. Fucosterol inhibited cell proliferation and cell-cycle progression in ovarian cancer cells. Additionally, fucosterol regulated the proliferation-related signaling pathways, the production of reactive oxygen species, mitochondrial function, endoplasmic reticulum stress, angiogenesis, and calcium homeostasis. Moreover, it decreased tumor formation in a zebrafish xenograft model. These results indicate that fucosterol could be used as a potential therapeutic agent in ovarian cancer.

A Comprehensive Review of the Nutraceutical and Therapeutic Applications of Red Seaweeds (Rhodophyta)

The red seaweed group (Rhodophyta) is one of the phyla of macroalgae, among the groups Phaeophyceae and Chlorophyta, brown and green seaweeds, respectively. Nowadays, all groups of macroalgae are getting the attention of the scientific community due to the bioactive substances they produce. Several macroalgae products have exceptional properties with nutraceutical, pharmacological, and biomedical interest. The main compounds studied are the fatty acids, pigments, phenols, and polysaccharides. Polysaccharides are the most exploited molecules, which are already widely used in various industries and are, presently, entering into more advanced applications from the therapeutic point of view. The focuses of this review are the red seaweeds' compounds, its proprieties, and its uses. Moreover, this work discusses new possible applications of the compounds of the red seaweeds.

Extraction and Modification of Macroalgal Polysaccharides for Current and Next-Generation Applications

Marine macroalgal (seaweed) polysaccharides are highly promising for next-generation applications in several industries. However, despite the reported comprehensive potential of these polysaccharides, commercial products are scarce on the market. Seaweed cultivations are increasing in number and production quantity, owing to an elevated global trend of utilization interest in seaweed. The extraction of polysaccharides from seaweed generally generates low yields, but novel methods are being developed to facilitate and improve the extraction processes. Current areas of applications for seaweed polysaccharides mainly take advantage of the physicochemical properties of certain polysaccharides, such as gelling, thickening and emulsifying. However, many of the numerous bioactivities reported are still only at research level and lack clinical evidence for commercialization. It has been suggested the construction of smaller units may generate better defined molecules that are more suitable for biomedical applications. Enzymatic modification is a promising tool for the generation of more defined, targeted biomolecules. This review covers; structural differences between the most predominant marine algal polysaccharides, extraction processes, modification alternatives, as well as a summary of current and potential next-generation application areas.