Seaweed as a source of novel nutraceuticals: sulfated polysaccharides and peptides

Seaweeds and derived bioactive compounds as food alternatives: Current status and future perspective in Africa

The urgency for food security and diversification has necessitated extensive exploration of all potential food options. Seaweeds, now considered potential functional foods are widely consumed across Asia and parts of Europe. In Africa, reports on consumption trends and food-related applications are scarce. About only 1% of the annually harvested ∼120,000 (fresh weight) tonnes of commercially useful eucheumatoids are utilized locally in the continent's top-producing country, Tanzania. Ultimately, the intensification of current efforts shall promote up-scaling of the seaweed industry. In this review, we have discussed the nutritional profile and nutraceutical potential of commercially viable species, paying attention to consumer safety measures. Also, prospective food-related application of seaweeds based on current international and local African consumption trends is reviewed. The review further addresses factors that hinder consumer acceptance in Africa and the up-scaling of the seaweed industry at large. This review aims to provide some theoretical reference for future developments and application of seaweed as food in Africa.

Conceptual design and environmental evaluation of the Biorefinery approach for R-phycoerythrin extraction and purification

Marine algae are considered promising resources both at present and in the near future. Their availability, together with their molecular structure and properties, increases their applicability in various sectors: food and feed, cosmetics, pharmaceuticals and bioenergy. However, the "bio" qualification does not always imply a lower impact compared to fossil-based process schemes. Therefore, to verify the suitability of algae-based scenarios from a sustainable and circular perspective, it is necessary to assess their sustainability potential through process modelling (scaling up from laboratory scale to evaluate their potential at commercial level), environmental assessment (using the Life Cycle Assessment (LCA) method) and circularity analysis (by quantifying circularity indicators focusing on recovery, waste management and effective use of resources). In this context, this research report focused on the techno-economic assessment (TEA) and LCA of three alternative scenarios based on the extraction of R-phycoerythrin from offshore harvested macroalgae: water extraction followed by enzymatic digestion (S01), ultrasound-assisted extraction (S02) and water extraction (S03). In addition, the evaluation of environmental, social and circularity indicators and the application of the Greenness Grid methodology were included. According to the results obtained, S01 is the most promising alternative among the three scenarios due to its process productivity, lower environmental impact and potential sustainable scenario score according to the Green Chemistry assessment. Regarding the economic perspective, S03 is the only one that does not reach economic viability. Future studies should focus on improving process efficiency, promoting the use of renewable energy resources and supporting technological progress in emerging extraction processes.

Extraction and Purification of Biopolymers from Marine Origin Sources Envisaging Their Use for Biotechnological Applications

Biopolymers are a versatile and diverse class of materials that has won high interest due to their potential application in several sectors of the economy, such as cosmetics, medical materials/devices, and food additives. In the last years, the search for these compounds has explored a wider range of marine organisms that have proven to be a great alternative to mammal sources for these applications and benefit from their biological properties, such as low antigenicity, biocompatibility, and biodegradability, among others. Furthermore, to ensure the sustainable exploitation of natural marine resources and address the challenges of 3R's policies, there is a current necessity to valorize the residues and by-products obtained from food processing to benefit both economic and environmental interests. Many extraction methodologies have received significant attention for the obtention of diverse polysaccharides, proteins, and glycosaminoglycans to accomplish the increasing demands for these products. The present review gives emphasis to the ones that can be obtained from marine biological resources, as agar/agarose, alginate and sulfated polysaccharides from seaweeds, chitin/chitosan from crustaceans from crustaceans, collagen, and some glycosaminoglycans such as chondroitin sulfate and hyaluronic acids from fish. It is offered, in a summarized and easy-to-interpret arrangement, the most well-established extraction and purification methodologies used for obtaining the referred marine biopolymers, their chemical structure, as well as the characterization tools that are required to validate the extracted material and respective features. As supplementary material, a practical guide with the step-by-step isolation protocol, together with the various materials, reagents, and equipment, needed for each extraction is also delivered is also delivered. Finally, some remarks are made on the needs still observed, despite all the past efforts, to improve the current extraction and purification procedures to achieve more efficient and green methodologies with higher yields, less time-consuming, and decreased batch-to-batch variability.

Ultrasound-assisted low-temperature extraction of polysaccharides from Lavandula angustifolia Mill.: optimization, structure characterization, and anti-inflammatory activity

Lavandula angustifolia Mill. is a traditional Chinese medicinal herb with high economic and pharmacological value. In this study, we optimized the conditions for low-temperature ultrasound-assisted extraction of L. angustifolia Mill. polysaccharides using response surface methodology (RSM), and two homopolysaccharides LAPW1 (33.6 kDa) and LAPS1 (95.9 kDa) were obtained after isolation and purification by DEAE-650 M and Superdex™ 200 chromatography. The primary structure of LAPS1 was determined using "partial acid hydrolysis, methylation, two-dimensional (2D NMR) spectroscopy" as the core method. The results revealed that LAPS1 is a heteropolysaccharide whose main chain consists of [-1)-β-Galp-(6→1)-α-Araf-(5→]3-1-α-Araf-(3→1)-α-Araf-(5→[1)-β-Galp-(6→1)-α-Araf-(5→]3-1-α-Araf-(5→1)-α-Araf-(5→[-1)-β-Galp-(6→1)-α-Araf-(5→]3. In vitro experiments revealed that LAPW1 and LAPS1 significantly reduced the production of the inflammatory cytokines Interleukin-1β (IL-1β), Interleukin-6 (IL-6), and Tumor Necrosis Factor (TNF), as well as the expression of Nitric Oxide Synthase 2 (NOS2) and release of nitric oxide (.NO) free radical in the inflammatory model established by lipopolysaccharide (LPS) stimulated RAW264.7. Besides, the zebrafish inflammatory model, stimulated by CuSO4, was employed to assess the impact of polysaccharides on neutrophil migration, indicating a notable decrease in zebrafish neutrophils and confirming their potential anti-inflammatory activity. These results indicate that polysaccharides from L. angustifolia Mill. be used in the development of functional foods and pharmaceutical products.

Algae-derived compounds: Bioactivity, allergenicity and technologies enhancing their values

As a rapidly growing source of human nutrients, algae biosynthesize diverse metabolites which have promising bioactivities. However, the potential allergenicity of algal components hinder their widespread adoption. This review provides a comprehensive review of various macro and micronutrients derived from algal biomass, with particular focus on bioactive compounds, including peptides, polyphenols, carotenoids, omega-3 fatty acids and phycocyanins. The approaches used to produce algal bioactive compounds and their health benefits (antioxidant, antidiabetic, cardioprotective, anti-inflammatory and immunomodulatory) are summarised. This review particularly focuses on the state-of-the-art of precision fermentation, encapsulation, cold plasma, high-pressure processing, pulsed electric field, and subcritical water to reduce the allergenicity of algal compounds while increasing their bioactivity and bioavailability. By providing insights into current challenges of algae-derived compounds and opportunities for advancement, this review contributes to the ongoing discourse on maximizing their application potential in the food nutraceuticals, and pharmaceuticals industries.

Use of micro and macroalgae extracts for the control of vector mosquitoes

Mosquitoes are one of the most dangerous vectors of human diseases such as malaria, dengue, chikungunya, and Zika virus. Controlling these vectors is a challenging responsibility for public health authorities worldwide. In recent years, the use of products derived from living organisms has emerged as a promising approach for mosquito control. Among these living organisms, algae are of great interest due to their larvicidal properties. Some algal species provide nutritious food for larvae, while others produce allelochemicals that are toxic to mosquito larvae. In this article, we reviewed the existing literature on the larvicidal potential of extracts of micro- and macroalgae, transgenic microalgae, and nanoparticles of algae on mosquitoes and their underlying mechanisms. The results of many publications show that the toxic effects of micro- and macroalgae on mosquitoes vary according to the type of extraction, solvents, mosquito species, exposure time, larval stage, and algal components. A few studies suggest that the components of algae that have toxic effects on mosquitoes show through synergistic interaction between components, inhibition of feeding, damage to gut membrane cells, and inhibition of digestive and detoxification enzymes. In conclusion, algae extracts, transgenic microalgae, and nanoparticles of algae have shown significant larvicidal activity against mosquitoes, making them potential candidates for the development of new mosquito control products.

Impact of Harvest Month and Drying Process on the Nutritional and Bioactive Properties of Wild Palmaria palmata from Atlantic Canada

The macroalga Palmaria palmata could be a sustainable and nutritional food resource. However, its composition may vary according to its environment and to processing methods used. To investigate these variations, wild P. palmata from Quebec were harvested in October 2019 and June 2020, and dried (40 °C, ≃5 h) or stored as frozen controls (-80 °C). The chemical (lipids, proteins, ash, carbohydrates, fibers), mineral (I, K, Na, Ca, Mg, Fe), potential bioactive compound (carotenoids, polyphenols, β-carotene, α-tocopherol) compositions, and the in vitro antioxidant activity and angiotensin-converting enzyme (ACE) inhibition potential of water-soluble extracts were determined. The results suggested a more favorable macroalgae composition in June with a higher content of most nutrients, minerals, and bioactive compounds. October specimens were richer only in carbohydrates and carotenoids. No significant differences in antioxidant or anti-ACE inhibitory activities were found between the two harvest months. The drying process did not significantly impact the chemical and mineral compositions, resulting in only small variations. However, drying had negative impacts on polyphenols and anti-ACE activities in June, and on carotenoids in October. In addition, a concentration effect was observed for carotenoids, β-carotene and α-tocopherol in June. To provide macroalgae of the highest nutritional quality, the drying process for June specimens should be selected.

Variation of the Nutritional Composition and Bioactive Potential in Edible Macroalga Saccharina latissima Cultivated from Atlantic Canada Subjected to Different Growth and Processing Conditions

Macroalgae are a new food source in the Western world. The purpose of this study was to evaluate the impact of harvest months and food processing on cultivated Saccharina latissima (S. latissima) from Quebec. Seaweeds were harvested in May and June 2019 and processed by blanching, steaming, and drying with a frozen control condition. The chemical (lipids, proteins, ash, carbohydrates, fibers) and mineral (I, K, Na, Ca, Mg, Fe) compositions, the potential bioactive compounds (alginates, fucoidans, laminarans, carotenoids, polyphenols) and in vitro antioxidant potential were investigated. The results showed that May specimens were significantly the richest in proteins, ash, I, Fe, and carotenoids, while June macroalgae contained more carbohydrates. The antioxidant potential of water-soluble extracts (Oxygen Radical Absorbance Capacity [ORAC] analysis-625 µg/mL) showed the highest potential in June samples. Interactions between harvested months and processing were demonstrated. The drying process applied in May specimens appeared to preserve more S. latissima quality, whereas blanching and steaming resulted in a leaching of minerals. Losses of carotenoids and polyphenols were observed with heating treatments. Water-soluble extracts of dried May samples showed the highest antioxidant potential (ORAC analysis) compared to other methods. Thus, the drying process used to treat S. latissima harvested in May seems to be the best that should be selected.

Alginate industrial waste streams as a promising source of value-added compounds valorization

The alginate industry processes more than hundred thousand tons per year of algae in Europe, discarding around 80% of the algae biomass as different solid/liquid residual streams. In this work, Saccharina latissima and Ascophyllum nodosum, their generated alginates and all residual fractions generated in the process were characterized in terms of lipid, ash, protein content, and the carbohydrate composition and antioxidant capacities analyzed. The first fraction after acid treatment (ca. 50% of the initial dry biomass) was rich in phlorotannins (15 mg GAE/g) and bioactive fucoidans (15-70%), with a high sulfation degree in A. nodosum. Two fractions generated from the solid residue, one soluble and another insoluble (Ra and Rb, respectively), constituted 9% and 5-8% of the initial biomass and showed great potential as a source of soluble protein (30% for S. latissima), and cellulose (70%) or fucoidan, respectively. Valorization strategies are suggested for these waste streams, evidencing their high potential as bioactive, texturizing or nutritional added-value ingredients for cosmetic, food, feed or pharmaceutical applications.

The Efficacy of Double-Heart Nursing in Combination with Seaweed Polysaccharide for Patients with Coronary Heart Disease Complicated with Diabetes: A Pilot, Randomized Clinical Trial

Objective

To study and explore the effect of double-heart nursing combined with seaweed polysaccharide on improving the self-efficacy and quality of life of patients with coronary heart disease and diabetes.

Methods

Eligible 214 patients with coronary heart disease and diabetes who were diagnosed and treated in our hospital between year 2017 and 2020 were randomized at a ratio of 1 : 1 to either control group (seaweed polysaccharide) or observation group (double-heart nursing combined with seaweed polysaccharide). The self-efficacy and quality of life of the two groups of patients after treatment were compared.

Results

The observation group reported a lower blood glucose level after treatment vs. the control group [(6.28 ± 4.49/8.24 ± 2.01) vs. (7.74 ± 4.18/11.41 ± 3.12)] (p < 0.05); a lower incidence of lesions in the observation group versus the control group after treatment (p < 0.05); and significantly lower SAS and SDS scores of the observation group vs. the control group was observed [(41.27 ± 4.08/43.81 ± 2.93) vs. (62.74 ± 3.48/61.58 ± 3.85)] (p < 0.05). Regarding the self-efficacy, the observation group was superior to the control group after treatment (p < 0.05). The treatment with double-heart nursing combined with seaweed polysaccharide was associated with the improvement of the quality of life with respect to social function, psychological function, and material life (each p < 0.05). The observation obtained a significantly higher satisfaction rate in comparison with the control group [107 (98.13%) vs.95 (88.80%)] (p < 0.05).

Conclusion

Seaweed polysaccharide and double-heart nursing might be practical in improving the self-efficacy and quality of life of patients with coronary heart disease and diabetes mellitus, compared with conventional clinical treatment alone.

Health benefits and potential applications of fucoidan (FCD) extracted from brown seaweeds in aquaculture: An updated review

Nowadays, the application of immunomodulators in aquaculture has become of an urgent need because of high incidence of fish and shrimp diseases. For a long time, researchers have paid great interest to find suitable, relatively economical, and environmentally safe immunostimulant products to be used either as feed or water additives to boost immunity and increase the resistance of fish and shrimp against the challenging pathogens. Probiotics, prebiotics, synbiotics, phytobiotics, herbal extracts, microalgae, macroalgae, and essential oils have been extensively evaluated. Brown seaweeds (Phaeophyceae) are a large group of multi-cellular macroalgae that are widely distributed in marine aquatic environments. They are abundant in several bioactive sulfated polysaccharides known as fucoidan (FCD). Research studies demonstrated the beneficial functions of FCD in human medicine because of its immunomodulating, antioxidant, anti-allergic, antitumor, antiviral, anti-inflammatory, and hepatoprotective effects. In aquaculture, several researchers have tested the benefits and potential applications of FCD in aquafeed. This literature review provides an updated information and key references of research studies that focused principally on using FCD in aquaculture. Its effects on growth, intestinal health, antioxidant capacity, and immune responses of several finfish and shellfish species will be discussed. This review paper will also highlight the potential efficacy and mechanisms of FCD in the modulation of toxicity signs and increasing the resistance of fish and shrimp against bacterial and viral infections. Hence, this contribution will be valuable to maintain aquaculture sustainability and to improve the health and welfare of farmed fish and shrimp.

Anti-inflammatory, anti-infectious and anti-cancer potential of marine algae and sponge: A review

Marine organisms are potentially a pretty good source of highly bioactive secondary metabolites that are best known for their anti-inflammation, anti-infection, and anti-cancer potential. The growing threat of bacterial resistance to synthetic antibiotics, is a potential source to screen terrestrial and marine natural organisms to discover promising anti-inflammatory and antimicrobial agents which can synergistically overcome the inflammatory and infectious disases. Algae and sponge have been studied enormously to evaluate their medicinal potential to fix variety of diseases, especially inflammation, infections, cancers, and diabetes. Cytarabine is the first isolated biomolecule from marine organism which was successfully practiced in clinical setup as chemotherapeutic agent against xylogenous leukemia both in acute and chronic conditions. This discovery opened the horizon for systematic evaluation of broad range of human disorders. This review is designed to look into the literature reported on anti-inflammatory, anti-infectious, and anti-cancerous potential of algae and sponge to refine the isolated compounds for value addition process.

Antimicrobial and Antioxidant Potential of Scenedesmus obliquus Microalgae in the Context of Integral Biorefinery Concept

Small-scale photobioreactors (PBRs) in the inoculum stage were designed with internal (red or green) and external white LED light as an initial step of a larger-scale installation aimed at fulfilling the integral biorefinery concept for maximum utilization of microalgal biomass in a multifunctional laboratory. The specific growth rate of Scenedesmus obliquus (Turpin) Kützing biomass for given cultural conditions was analyzed by using MAPLE software. For the determination of total polyphenols, flavonoids, chlorophyll “a” and “b”, carotenoids and lipids, UHPLC-HRMS, ISO-20776/1, ISO-10993-5 and CUPRAC tests were carried out. Under red light growing, a higher content of polyphenols was found, while the green light favoured the flavonoid accumulation in the biomass. Chlorophylls, carotenoids and lipids were in the same order of magnitude in both samples. The dichloromethane extracts obtained from the biomass of each PBR synergistically potentiated at low concentrations (0.01–0.05 mg/mL) the antibacterial activity of penicillin, fluoroquinolones or oregano essential oil against the selected food-borne pathogens (Staphylococcus aureus, Escherichia coli and Salmonella typhimurium) without showing any in vitro cytotoxicity. Both extracts exhibited good cupric ion-reducing antioxidant capacity at concentrations above 0.042–0.08 mg/mL. The UHPLC-HRMS analysis revealed that both extracts contained long chain fatty acids and carotenoids thus explaining their antibacterial and antioxidant potential. The applied engineering approach showed a great potential to modify microalgae metabolism for the synthesis of target compounds by S. obliquus with capacity for the development of health-promoting nutraceuticals for poultry farming.

Advance research in biomedical applications on marine sulfated polysaccharide

Marine ecosystem associated organisms are an affluent source of bioactive compounds. Polysaccharides with unique structural and practical entities have gained special studies interest inside the current biomedical zone. Polysaccharides are the main components of marine algae, plants, animals, insects, and microorganisms. In recent times research on seaweed is more persistent for extraction of natural bioactive "Sulfated polysaccharides" (SPs). The considerable amount of SP exists in the algae in the form of fucans, fucoidans, carrageenans, ulvan, etc. Major function of SPs is to act as a defensive lattice towards the infective organism. All SPs possess the high potential and possess a broad range of therapeutic applications as antitumor, immunomodulatory, vaccine adjuvant, anti-inflammatory, anticoagulant, antiviral, antiprotozoal, antimicrobial, antilipemic, therapy of regenerative medicine, also in drug delivery and tissue engineering application. This review aims to discuss the biomedicine applications of sulfated polysaccharides from marine seaweeds.

Marine Algae-Derived Bioactive Compounds: A New Wave of Nanodrugs?

Marine algae are rich in bioactive nutraceuticals (e.g., carbohydrates, proteins, minerals, fatty acids, antioxidants, and pigments). Biotic (e.g., plants, microorganisms) and abiotic factors (e.g., temperature, pH, salinity, light intensity) contribute to the production of primary and secondary metabolites by algae. Easy, profitable, and sustainable recovery methods include novel solid-liquid and liquid-liquid extraction techniques (e.g., supercritical, high pressure, microwave, ultrasound, enzymatic). The spectacular findings of algal-mediated synthesis of nanotheranostics has attracted further interest because of the availability of microalgae-based natural bioactive therapeutic compounds and the cost-effective commercialization of stable microalgal drugs. Algal extracts can serve as stabilizing/capping and reducing agents for the synthesis of thermodynamically stable nanoparticles (NPs). Different types of nanotherapeutics have been synthesized using physical, chemical, and biological methods. Marine algae are a fascinating source of lead theranostics compounds, and the development of nanotheranostics has been linked to enhanced drug efficacy and safety. Indeed, algae are remarkable nanobiofactories, and their pragmatic properties reside in their (i) ease of handling; (ii) capacity to absorb/accumulate inorganic metallic ions; (iii) cost-effectiveness; and (iv) capacity of eco-friendly, rapid, and healthier synthesis of NPs. Preclinical and clinical trials shall enable to really define effective algal-based nanotherapies. This review aims to provide an overview of the main algal compounds that are nutraceuticals and that can be extracted and purified for nanotheranostic purposes.

Production of Ulvan Oligosaccharides with Antioxidant and Angiotensin-Converting Enzyme-Inhibitory Activities by Microbial Enzymatic Hydrolysis

Seaweed oligosaccharides have attracted attention in food, agricultural, and medical applications recently. Compared to red and brown seaweeds, fewer studies have focused on the biological activity of green seaweed’s oligosaccharides. This study aimed to produce bioactive ulvan oligosaccharides via enzymatic hydrolysis from green seaweed Ulva lactuca. Ulvan, a water-soluble polysaccharide, was obtained by hot water extraction. Two isolated marine bacteria, Pseudomonas vesicularis MA103 and Aeromonas salmonicida MAEF108, were used to produce multiple hydrolases, such as ulvanolytic enzymes, amylase, cellulase, and xylanase, to degrade the ulvan extract. An ultrafiltration system was used to separate the enzymatic hydrolysate to acquire the ulvan oligosaccharides (UOS). The characteristics of the ulvan extract and the UOS were determined by yield, reducing sugar, uronic acid, sulfate group, and total phenols. The FT-IR spectrum indicated that the ulvan extract and the UOS presented the bands associated with O-H, C=O, C-O, and S=O stretching. Angiotensin I converting enzyme (ACE) inhibition and antioxidant activities in vitro were evaluated in the ulvan extract and the UOS. These results provide a practical approach to producing bioactive UOS by microbial enzymatic hydrolysis that can benefit the development of seaweed-based products at the industrial scale.

Anemonia sulcata and Its Symbiont Symbiodinium as a Source of Anti-Tumor and Anti-Oxoxidant Compounds for Colon Cancer Therapy: A Preliminary in Vitro Study

Simple Summary

Colorectal cancer is one of the most frequent types of cancer in the population. Recently, invertebrate marine animals have been investigated for the presence of natural products which can damage tumor cells, prevent their spread to other tissues or avoid cancer develop. We analyzed the anemone Anemonia sulcata with and without the presence of its microalgal symbiont (Symbiodinium) as a source of bioactive molecules for the colorectal cancer therapy and prevention. Colon cancer tumor cells were exposed to Anemone extracts observing a remarkable cell death and a great antioxidant capacity. These preliminary results support that Anemonia sulcata could be a source of bioactive compounds against colorectal cancer and that the absence of its symbiont may enhance these properties. Further studies will be necessary to define the bioactive compounds of Anemonia sulcata and their mechanisms of action.

Abstract

Recently, invertebrate marine species have been investigated for the presence of natural products with antitumor activity. We analyzed the invertebrate Anemonia sulcata with (W) and without (W/O) the presence of its microalgal symbiont Symbiodinium as a source of bioactive compounds that may be applied in the therapy and/or prevention of colorectal cancer (CRC). Animals were mechanically homogenized and subjected to ethanolic extraction. The proximate composition and fatty acid profile were determined. In addition, an in vitro digestion was performed to study the potentially dialyzable fraction. The antioxidant and antitumor activity of the samples and the digestion products were analyzed in CRC cells in vitro. Our results show a high concentration of polyunsaturated fatty acid in the anemone and a great antioxidant capacity, which demonstrated the ability to prevent cell death and a high antitumor activity of the crude homogenates against CRC cells and multicellular tumor spheroids, especially W/O symbiont. These preliminary results support that Anemonia sulcata could be a source of bioactive compounds with antioxidant and antitumor potential against CRC and that the absence of its symbiont may enhance these properties. Further studies will be necessary to define the bioactive compounds of Anemonia sulcata and their mechanisms of action.

Therapeutic Effect of Seaweed Derived Xanthophyl Carotenoid on Obesity Management; Overview of the Last Decade

Present-day lifestyles associated with high calorie-fat intake and accumulation, as well as energy imbalance, have led to the development of obesity and its comorbidities, which have emerged as some of the major health issues globally. To combat the disease, many studies have reported the anti-obesity effects of natural compounds in foods, with some advantages over chemical treatments. Carotenoids, such as xanthophyll derived from seaweeds, have attracted the attention of researchers due to their notable biological activities, which are associated mainly with their antioxidant properties. Their involvement in oxidative stress modulation, the regulation of major transcription factors and enzymes, and their antagonistic effects on various obesity parameters have been examined in both in vitro and in vivo studies. The present review is a collation of published research over the last decade on the antioxidant properties of seaweed xanthophyll carotenoids, with a focus on fucoxanthin and astaxanthin and their mechanisms of action in obesity prevention and treatment.

Human exposure assessment to macro- and trace elements in the most consumed edible seaweeds in Europe

Seaweed consumption has increased considerably in Europe as a result of new trends in food. The macroelement (Na, Ca, K, Mg) and trace element (B, Ba, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Sr, V, Zn) levels in different species of edible brown seaweeds were determined by inductively coupled plasma optical emission spectrometry (ICP-OES). European Himanthalia elongata species had the highest recorded concentrations of K (57480 mg/kg dry weight). Asian Undaria pinnatifida species had the highest Fe content (58.8 mg/kg dw). Five grams/day of dehydrated seaweed of the Asian U. pinnatifida species mainly contributes to the admissible daily intake of Mg (9.32% adults) and Na (7.05% adults). In any case which exceeds the maximum intake values of any of the elements analyzed, the macro- and trace element levels can vary considerably in a short period of time, so it is necessary to assess the toxic risk in edible seaweeds.

Natural products against cancer: Review on phytochemicals from marine sources in preventing cancer

Marine natural products have as of now been acknowledged as the most important source of bioactive substances and drug leads. Marine flora and fauna, such as algae, bacteria, sponges, fungi, seaweeds, corals, diatoms, ascidian etc. are important resources from oceans, accounting for more than 90% of the total oceanic biomass. They are taxonomically different with huge productive and are pharmacologically active novel chemical signatures and bid a tremendous opportunity for discovery of new anti-cancer molecules. The water bodies a rich source of potent molecules which improve existence suitability and serve as chemical shield against microbes and little or huge creatures. These molecules have exhibited a range of biological properties antioxidant, antibacterial, antitumour etc. In spite of huge resources enriched with exciting chemicals, the marine floras and faunas are largely unexplored for their anticancer properties. In recent past, numerous marine anticancer compounds have been isolated, characterized, identified and are under trials for human use. In this write up we have tried to compile about marine-derived compounds anticancer biological activities of diverse flora and fauna and their underlying mechanisms and the generous raise in these compounds examined for malignant growth treatment in the course of the most recent quite a long while.

Brown seaweed (AquaArom) supplementation increases food intake and improves growth, antioxidant status and resistance to temperature stress in Atlantic salmon, Salmo salar

Seaweeds represent a vast resource that remains underutilized as an ingredient in aquafeeds. Here we probed the effect of addition of AquaArom, a seaweed meal derived from brown seaweeds (Laminaria sp., kelp), to fish feed on growth performance, antioxidant capacity and temperature responsiveness of mitochondrial respiration. A commercial salmonid feed was mixed with 0 (control), 3, 6 and 10% seaweed and fed to Atlantic salmon (Salmo salar) smolts for 30 days. The smolts consumed more of the seaweed-supplemented food relative to the control and there were no mortalities. Compared with the control, the final fish weight, standard length, weight gain and SGR were higher in fish fed diets supplemented with the 3 and 10% seaweed, while growth performance for fish maintained on 6% seaweed remained neutral. Importantly, seaweed supplementation increased protein efficiency ratio (PER) and tended to improve food conversion ratio (FCR). Although the hepatosomatic and visceral indices did not change, whole gut and intestinal weights and lengths were higher in fish maintained on seaweed-supplemented diets suggesting increased retention time and a larger surface area for food digestion and nutrient absorption. Measurement of antioxidant status revealed that seaweed supplementation dose-dependently increased plasma total antioxidant capacity as well as the level of glutathione, and activities of catalase and superoxide dismutase in liver mitochondria. Moreover, seaweed supplementation reduced the effect of acute temperature rise on mitochondrial respiration and proton leak. Overall, these data suggest that AquaArom can be mixed with fish food up to 10% to increase food consumption and enhance growth performance, as well as to improve antioxidant capacity and alleviate adverse effects of stressors such as temperature in fish.

Isolation and Immunocharacterization of Lactobacillus salivarius from the Intestine of Wakame-Fed Pigs to Develop Novel "Immunosynbiotics"

Emerging threats of antimicrobial resistance necessitate the exploration of effective alternatives for healthy livestock growth strategies. 'Immunosynbiotics', a combination of immunoregulatory probiotics and prebiotics with synergistic effects when used together in feed, would be one of the most promising candidates. Lactobacilli are normal residents of the gastrointestinal tract of pigs, and many of them are able to exert beneficial immunoregulatory properties. On the other hand, wakame (Undaria pinnafida), an edible seaweed, has the potential to be used as an immunoregulatory prebiotic when added to livestock feed. Therefore, in order to develop a novel immunosynbiotic, we isolated and characterized immunoregulatory lactobacilli with the ability to utilize wakame. Following a month-long in vivo wakame feeding trial in 8-week-old Landrace pigs (n = 6), sections of intestinal mucous membrane were processed for bacteriological culture and followed by identification of pure colonies by 16S rRNA sequence. Each isolate was characterized in vitro in terms of their ability to assimilate to the wakame and to differentially modulate the expression of interleukin-6 (IL-6) and interferon beta (IFN-β) in the porcine intestinal epithelial (PIE) cells triggered by Toll-like receptor (TLR)-4 and TLR-3 activation, respectively. We demonstrated that feeding wakame to pigs significantly increased the lactobacilli population in the small intestine. We established a wakame-component adjusted culture media that allowed the isolation and characterization of a total of 128 Lactobacilli salivarius colonies from the gut of wakame-fed pigs. Interestingly, several L. salivarius isolates showed both high wakame assimilation ability and immunomodulatory capacities. Among the wakame assimilating isolates, L. salivarius FFIG71 showed a significantly higher capacity to upregulate the IL-6 expression, and L. salivarius FFIG131 showed significantly higher capacity to upregulate the IFN-β expression; these could be used as immunobiotic strains in combination with wakame for the development of novel immunologically active feeds for pigs.

Risks and benefits of consuming edible seaweeds

Recent interest in seaweeds as a source of macronutrients, micronutrients, and bioactive components has highlighted prospective applications within the functional food and nutraceutical industries, with impetus toward the alleviation of risk factors associated with noncommunicable diseases such as obesity, type 2 diabetes, and cardiovascular disease. This narrative review summarizes the nutritional composition of edible seaweeds; evaluates the evidence regarding the health benefits of whole seaweeds, extracted bioactive components, and seaweed-based food products in humans; and assesses the potential adverse effects of edible seaweeds, including those related to ingestion of excess iodine and arsenic. If the potential functional food and nutraceutical applications of seaweeds are to be realized, more evidence from human intervention studies is needed to evaluate the nutritional benefits of seaweeds and the efficacy of their purported bioactive components. Mechanistic evidence, in particular, is imperative to substantiate health claims.

In Vivo Evaluation of the Antioxidant Activity and Protective Action of the Seaweed Gracilaria birdiae

The red seaweed Gracilaria birdiae (GB) is farmed and used as food in northeast Brazil. However, the economic potential of this seaweed has been explored little. To enable direct consumption and/or product diversification from GB, it is necessary to evaluate its effect in vivo. In this study, the food of mice was improved with the addition of GB. After 21 days, the consumption of seaweed reduced the weight gain and blood glucose levels in mice. In addition, it increased the trolox equivalent antioxidant capacity and glutathione reductase and catalase levels compared to those of the control group. In addition, some mice also received carbon tetrachloride (CCl4). In this case, histological, enzymatic, and antioxidant tests showed that the seaweed could protect animals from damage caused by this toxic agent. In addition, GB aqueous extract (AE) inhibited 50% of 3T3-L1 cell differentiation into adipocytes, whereas GB ethanolic extract was not effective. AE is composed mainly of sulfated polysaccharides. The results of the present study indicate that the alga GB protected the mice from CCl4-induced damage, indicating that the seaweed exhibits protective action in vivo. In addition, GB decreased the animal weight gain, which was mainly due to the action of the sulfated polysaccharides synthesized by this seaweed.

Treatment of reactive hypoglycemia with the macrobiotic Ma-pi 2 diet as assessed by continuous glucose monitoring: The MAHYP randomized crossover trial

BACKGROUND AND AIMS

Nutritional therapy is recommended for management of reactive hypoglycemia (RH), a condition characterized by hypoglycemia that occurs within four hours after a meal. The macrobiotic Ma-Pi 2 diet improves glycemic control in subjects with type 2 diabetes. We explored the effect of this diet on outcomes in non-diabetic individuals with RH.

MATERIALS AND METHODS

Twelve subjects with RH were randomized to the Ma-Pi 2 diet for three days and a control diet for three days in a randomized crossover design. Subjects received snacks on two days out of each three-day period only, and were monitored using continuous glucose monitoring. The 24-h period was divided into daytime (08:00-22:30h [subdivided into 'daytime without snacks' and 'daytime with snacks']) and night-time (22:31-07:59h). The effects of the two diets on the number of RH events (blood glucose <70mg/dL [3.9mmol/L]) and the percentage distribution of glucose readings within each of 16 glycemic intervals from <40mg/dL (2.2mmol/L) to >180mg/dL (4.4mmol/L) were determined.

RESULTS

There were significantly fewer RH events on the Ma-Pi 2 diet than the control diet during daytime without snacks (-2.5 events; 95% CI: -7.5, 0.0; P=0.022) and daytime with snacks (-4.25 events; 95% CI: -7.5; -2.0; P=0.013) but no difference at night. The percentage of glucose readings in the interval 71-80mg/dL (3.9-4.4mmol/L) was significantly higher on the control diet during daytime with and without snacks (P=0.03 for both), while the percentage of glucose readings in the interval 91-100mg/dL (5.1-5.6mmol/L) was significantly higher on the Ma-Pi 2 diet during daytime without snacks (P=0.02).

CONCLUSIONS

The macrobiotic Ma-Pi 2 diet reduced blood glucose excursions during the day, thereby facilitating glycemic control in subjects with RH. The Ma-Pi 2 diet represents an effective nutritional tool for management of RH.

A Systematic Approach to Discover and Characterize Natural Plant Biostimulants

The use of natural plant biostimulants is proposed as an innovative solution to address the challenges to sustainable agriculture, to ensure optimal nutrient uptake, crop yield, quality, and tolerance to abiotic stress. However, the process of selection and characterization of plant biostimulant matrices is complex and involves a series of rigorous evaluations customized to the needs of the plant. Here, we propose a highly differentiated plant biostimulant development and production platform, which involves a combination of technology, processes, and know-how. Chemistry, biology and omic concepts are combined/integrated to investigate and understand the specific mode(s) of action of bioactive ingredients. The proposed approach allows to predict and characterize the function of natural compounds as biostimulants. By managing and analyzing massive amounts of complex data, it is therefore possible to discover, evaluate and validate new product candidates, thus expanding the uses of existing products to meet the emerging needs of agriculture.

Reviews on Mechanisms of In Vitro Antioxidant Activity of Polysaccharides

It is widely acknowledged that the excessive reactive oxygen species (ROS) or reactive nitrogen species (RNS) induced oxidative stress will cause significant damage to cell structure and biomolecular function, directly or indirectly leading to a number of diseases. The overproduction of ROS/RNS will be balanced by nonenzymatic antioxidants and antioxidant enzymes. Polysaccharide or glycoconjugates derived from natural products are of considerable interest from the viewpoint of potent in vivo and in vitro antioxidant activities recently. Particularly, with regard to the in vitro antioxidant systems, polysaccharides are considered as effective free radical scavenger, reducing agent, and ferrous chelator in most of the reports. However, the underlying mechanisms of these antioxidant actions have not been illustrated systematically and sometimes controversial results appeared among various literatures. To address this issue, we summarized the latest discoveries and advancements in the study of antioxidative polysaccharides and gave a detailed description of the possible mechanisms.

Marine polysaccharides from algae with potential biomedical applications

There is a current tendency towards bioactive natural products with applications in various industries, such as pharmaceutical, biomedical, cosmetics and food. This has put some emphasis in research on marine organisms, including macroalgae and microalgae, among others. Polysaccharides with marine origin constitute one type of these biochemical compounds that have already proved to have several important properties, such as anticoagulant and/or antithrombotic, immunomodulatory ability, antitumor and cancer preventive, antilipidaemic and hypoglycaemic, antibiotics and anti-inflammatory and antioxidant, making them promising bioactive products and biomaterials with a wide range of applications. Their properties are mainly due to their structure and physicochemical characteristics, which depend on the organism they are produced by. In the biomedical field, the polysaccharides from algae can be used in controlled drug delivery, wound management, and regenerative medicine. This review will focus on the biomedical applications of marine polysaccharides from algae.

Antiviral effect of sulfated Chuanmingshen violaceum polysaccharide in chickens infected with virulent Newcastle disease virus

Newcastle disease virus (NDV) belonging to the Paramyxovirinae subfamily is one of the most devastating pathogens in poultry. Although vaccines are widely applied to control the infection, outbreaks of Newcastle disease (ND) repeatedly happen. Currently, there are no alternative control measures available for ND. In the present study, we found that sulfated Chuanmingshen violaceum polysaccharide (sCVPS) were potent inhibitors of NDV in specific pathogen free chickens infected with a virulent strain. With sCVPS treatment, the survival rate increased by almost 20% and virus titers in test organs, including brain, lung, spleen and thymus, were significantly decreased. The sCVPS also exhibited the ability to prevent viral transmission by reducing the amount of virus shed in saliva and feces. Higher concentrations of interferon α and γ in serum were detected in chickens treated with sCVPS, indicating that one of the antiviral mechanisms may be attributed to the property of immunoenhancement. Histopathological examination showed that sCVPS could alleviate the tissue lesions caused by NDV infection. These results suggest that sCVPS are expected to be a new alternative control measure for NDV infection and further studies could be carried out to evaluate the antiviral activity of sCVPS against other paramyxoviruses.

Effects of dietary fermented seaweed and seaweed fusiforme on growth performance, carcass parameters and immunoglobulin concentration in broiler chicks

This study was conducted to investigate the effects of brown seaweed (Undaria pinnatifida) by-product and seaweed fusiforme (Hizikia fusiformis) by-product supplementation on growth performance and blood profiles including serum immunoglobulin (Ig) in broilers. Fermentation of seaweeds was conducted by Bacillus subtilis and Aspergillus oryzae. In a 5-wk feeding trial, 750 one-d-old broiler chicks were divided into 5 groups, and were assigned to the control diet or experimental diets including control+0.5% brown seaweed (BS) by-product, control+0.5% seaweed fusiforme (SF) by-product, control+0.5% fermented brown seaweed (FBS) by-product, and control+0.5% fermented seaweed fusiforme (FSF) by-product. As a consequence, body weight gain (BWG) and gain:feed of seaweed by-product groups were clearly higher, when compared to those of control diet group from d 18 to 35 and the entire experimental period (p<0.05). In mortality rate, seaweed by-product groups were significantly lower when compared to control diet group during entire experimental period (p<0.05). However, Feed Intake of experimental diets group was not different from that of the control group during the entire experimental period. Whereas, Feed Intake of fermented seaweed by-product groups was lower than that of non-fermented seaweed groups (p<0.05). Total organ weights, lipids, and glutamic oxalacetic transaminase (GOT) of all treatment groups were not different from those of control group. However, glutamic pyruvate transaminase (GPT) of all treatment groups was higher than that of control group at d 17 (p<0.05). In case of serum Igs concentration, the concentration of IgA antibody in BS, SF, FSF treatment groups was significantly higher than in control group at d 35 (p<0.01). IgA concentration in FBS supplementation groups was negligibly decreased when compared to the control group. IgM concentration in the serums of all treatment groups was significantly higher than in control group (p<0.05) and in fermented seaweed by-product groups were much higher than in non-fermented seaweed groups (p<0.05). On the other hand, IgG concentrations in all treatment groups were lower than in control group (p<0.05). Taken together, our results suggest that by-product dietary supplementation of BS, SF, FBS, and FSF in poultry may provide positive effects of growth performance and immune response.

Antifatigue effect of Gracilaria eucheumoides in mice

Gracilaria eucheumoides Linn (Gracilariaceae; G. eucheumoides) is abundant in dietary fiber, which aids the clearance of excess cholesterol from the blood and maintains stable blood glucose levels. The aim of the present study was to investigate the antifatigue effect of G. eucheumoides in mice and the physiological and molecular mechanisms underlying this effect. Mice were randomly divided into four groups and three of the groups were administered different doses of G. eucheumoides extract. A loaded swimming test demonstrated that the swimming times of the low-, medium- and high-dose groups were longer than those of the control group. Examinations revealed that the liver and muscle glycogen, lactate dehydrogenase and blood glucose concentration levels of the treatment groups were higher than those of the control group (P<0.05). However, this was not the case for lactic acid concentration (P>0.05). Quantitative polymerase chain reaction showed that the gene expression levels of glucose transport protein 4 and AMP-activated protein kinase in the medium-dose group exhibited the largest increases, compared with the other treatment groups, and were 3.0- and 1.8-fold higher than those in the control group, respectively. The results of the present study indicated that G. eucheumoides exerts an antifatigue effect on mice.

Seaweeds as potential therapeutic interventions for the metabolic syndrome

Seaweeds are a characteristic part of the traditional diet in countries such as Japan and Korea; these countries also have a lower prevalence of metabolic syndrome than countries such as the USA and Australia. This suggests that seaweeds may contain compounds that reduce the characteristic signs of obesity, diabetes, hypertension, fatty liver and inflammation in the metabolic syndrome. Potentially bioactive compounds from seaweeds include polysaccharides, peptides, pigments, minerals and omega-3 fatty acids. This review emphasises current research on these compounds in isolated cells, animal models and patients. Key problems for future research include chemical characterisation of the bioactive principles, defining pharmacological responses in all aspects of the metabolic syndrome, determining if a therapeutic dose has been administered, and defining oral bioavailability of the active ingredients.

Marine algal natural products with anti-oxidative, anti-inflammatory, and anti-cancer properties

For their various bioactivities, biomaterials derived from marine algae are important ingredients in many products, such as cosmetics and drugs for treating cancer and other diseases. This mini-review comprehensively compares the bioactivities and biological functions of biomaterials from red, green, brown, and blue-green algae. The anti-oxidative effects and bioactivities of several different crude extracts of algae have been evaluated both in vitro and in vivo. Natural products derived from marine algae protect cells by modulating the effects of oxidative stress. Because oxidative stress plays important roles in inflammatory reactions and in carcinogenesis, marine algal natural products have potential for use in anti-cancer and anti-inflammatory drugs.

Therapeutic importance of sulfated polysaccharides from seaweeds: updating the recent findings

Seaweeds, being prolific sources of bioactive components have garnered unprecedented interest in recent times. The complex polysaccharides from the brown, red and green seaweeds possess broad spectrum therapeutic properties. Especially, the sulfated polysaccharides, viz. fucans, carrageenans and ulvans have exhibited strong antioxidant, antitumor, immunostimulatory, anti-inflammatory, pulmonary fibrosis anticoagulant/antithrombotic, lipid lowering, antiviral, antibacterial, antiprotozoan, hyperplasia prevention, gastrointestinal, regenerative and nano medicine applications. Considering the immense biomedical prospects of sulfated polysaccharides, the profound and emerging functional properties published in recent times will be discussed here with experimental evidences. The limitations of the seaweed-derived sulfated polysaccharides in healthcare will be summarized. Strategies to maximize extraction and bioavailability will be pondered.