Assessing the role of ulvan as immunonutrient in Solea senegalensis.

Immunonutrition is a promising and viable strategy for the development of prophylactic measures in aquaculture. Ulvan, a sulphated marine polysaccharide from green seaweeds, has many biological activities including the immunomodulatory ones. The aim of this study was to assess the short and long-term effects of an ulvan-rich extract obtained from U. ohnoi as immunonutrient in Senegalese sole juveniles. In this work, an ulvan-rich extract from Ulva ohnoi has been obtained by the hot water method and isolated by ethanol precipitation. The FTIR analysis revealed that the ulvan-rich extact had very similar characteristics to previously published ulvan spectra. The total sulfate and protein content was 24.85 ± 3.98 and 0.91 ± 0.04 %, respectively. In vitro assays performed in Senegalese sole (Solea senegalensis) macrophages showed that the ulvan obtained in this study did not compromise the cell viability at concentrations up to 1 mg ml-1 and expression levels of lyg, irf1, il6, il10, c7, tf and txn were significantly upregulated in a concentration dependent-manner. Finally, S. senegalensis juveniles were fed basal diets and diets supplemented with the ulvan-rich extract at ratios 1 and 2 % for 30 days and then, challenged with Photobacterium damselae subsp. piscicida (Phdp). Thereafter, ulvan was withdrawn from the diet and all juveniles were fed the basal diet for 30 days. At 30 days post withdrawal (dpw), juveniles were challenged with Phdp. The expression profiles of a set of genes related to the immune system in spleen were evaluated as well as the lysozyme, peroxidase and bactericidal activity in plasma. Dietary effects of 1 % ulvan resulted in a boost of the immune response and increased disease resistance at short-term whereas juveniles fed diets supplemented with 2 % ulvan showed a significant decrease in the bactericidal activity and lack of protection against Phdp. At long-term (30 days after the withdrawal of ulvan), an improved response was observed in juveniles previously fed 1 % ulvan.

Water-Soluble Saccharina latissima Polysaccharides and Relation of Their Structural Characteristics with In Vitro Immunostimulatory and Hypocholesterolemic Activities.

Brown macroalgae are an important source of polysaccharides, mainly fucose-containing sulphated polysaccharides (FCSPs), associated with several biological activities. However, the structural diversity and structure-function relationships for their bioactivities are still undisclosed. Thus, the aim of this work was to characterize the chemical structure of water-soluble Saccharina latissima polysaccharides and evaluate their immunostimulatory and hypocholesterolemic activities, helping to pinpoint a structure-activity relationship. Alginate, laminarans (F1, neutral glucose-rich polysaccharides), and two fractions (F2 and F3) of FCSPs (negatively charged) were studied. Whereas F2 is rich in uronic acids (45 mol%) and fucose (29 mol%), F3 is rich in fucose (59 mol%) and galactose (21 mol%). These two fractions of FCSPs showed immunostimulatory activity on B lymphocytes, which could be associated with the presence of sulphate groups. Only F2 exhibited a significant effect in reductions in in vitro cholesterol's bioaccessibility attributed to the sequestration of bile salts. Therefore, S. latissima FCSPs were shown to have potential as immunostimulatory and hypocholesterolemic functional ingredients, where their content in uronic acids and sulphation seem to be relevant for the bioactive and healthy properties.

Chemical Composition, Antioxidant, and Antitumor Activity of Fucoidan from the Brown Alga Dictyota dichotoma.

Brown macroalgae are a rich source of fucoidans with many pharmacological uses. This research aimed to isolate and characterize fucoidan from Dictyota dichotoma var. dichotoma (Hudson) J.V. Lamouroux and evaluate in vitro its antioxidant and antitumor potential. The fucoidan yield was 0.057 g/g algal dry wt with a molecular weight of about 48.6 kDa. In terms of fucoidan composition, the sulfate, uronic acid, and protein contents were 83.3 ± 5.20 mg/g fucoidan, 22.5 ± 0.80 mg/g fucoidan, and 26.1 ± 1.70 mg/g fucoidan, respectively. Fucose was the primary sugar component, as were glucose, galactose, mannose, xylose, and glucuronic acid. Fucoidan exhibited strong antioxidant potential that increased by more than 3 times with the increase in concentration from 0.1 to 5.0 mg/mL. Moreover, different concentrations of fucoidan (0.05-1 mg/mL) showed their ability to decrease the viability of Ehrlich ascites carcinoma cells in a time-dependent manner. These findings provided a fast method to obtain an appreciable amount of natural fucoidan with established structural characteristics as a promising compound with pronounced antioxidant and anticancer activity.

Improved Metal Cation Optosensing Membranes through the Incorporation of Sulphated Polysaccharides.

Optosensing chitosan-based membranes have been applied for the detection of heavy metals, especially in drinking water. The novelty of this study is based on the use of sulphated polysaccharides, in such optosensing membranes, aiming at an improved analytical performance. The sulphated polysaccharides, such as ulvan, fucoidan and chondroitin sulfate, were extracted from by-products and wastes of marine-related activities. The membranes were developed for the analysis of aluminum. The variation in the visible absorbance of the sensor membranes after the contact between the chromophore and the aluminum cation was studied. The membranes containing sulphated polysaccharides showed improved signals when compared to the chitosan-only membrane. As for the detection limits for the membranes containing ulvan, fucoidan and chondroitin sulfate, 0.17 mg L-1, 0.21 mg L-1 and 0.36 mg L-1 were obtained, respectively. The values were much lower than that obtained for the chitosan-only membrane, 0.52 mg L-1, which shows the improvement obtained from the sulphated polysaccharides. The results were obtained with the presence of CTAB in analysis solution, which forms a ternary complex with the aluminum cation and the chromophore. This resulted in an hyperchromic and batochromic shift in the absorption band. When in the presence of this surfactant, the membranes showed lower detection limits and higher selectivity.

Evaluating the antibacterial and antibiofilm potential of sulphated polysaccharides extracted from green algae Chlamydomonas reinhardtii.

AIM OF THE STUDY: In this study, antibacterial and antibiofilm potential of sulphated polysaccharides (SPs) extracted from Chlamydomonas reinhardtii (Cr) was evaluated against Neisseria mucosa, Escherichia coli, Streptococcus sp. and Bacillus subtilis. METHODS AND RESULTS: Antibacterial potential of Cr-SPs was evaluated by agar-cup diffusion, time-kill and colony-forming ability (CFU), minimum inhibitory and bactericidal concentration assays. Antibiofilm potential was evaluated by biofilm inhibition, eradication, extracellular-DNA, metabolic activity and microscopy assays. Cr-SPs at 0·5 mg ml-1 showed 34·52, 48·6, 66·1 and 55·6% reduced CFU in B. subtilis, Streptococcus, N. mucosa and E. coli respectively. Minimum inhibitory concentration of Cr-SPs was as low as 480 µg ml-1 for Streptococcus, N. mucosa and 420 µg ml-1 for B. subtilis and E. coli. At 1 mg ml-1 , Cr-SPs showed 50% biofilm inhibition, whereas 4-8 mg ml-1 showed 100% inhibition. Cr-SPs also effectively dissolved preformed biofilms. Dose-dependent reduction in extracellular DNA revealed that Cr-SPs interacts with the extra polymeric substance of the biofilm and destroys them. Light microscopy reconfirmed the above results. CONCLUSION: Cr-SPs not only inhibited biofilm formation but also effectively dissolved preformed-biofilms. SIGNIFICANCE AND IMPACT OF THE STUDY: The current study showed the promising potential of Cr-SPs as antibiofilm agents. Further validation will help in developing Cr-SPs as natural antibiotics against biofilm-causing bacteria.

Metabolites of Seaweeds as Potential Agents for the Prevention and Therapy of Influenza Infection.

CONTEXT: Seaweed metabolites (fucoidans, carrageenans, ulvans, lectins, and polyphenols) are biologically active compounds that target proteins or genes of the influenza virus and host components that are necessary for replication and reproduction of the virus. OBJECTIVE: This review gathers the information available in the literature regarding to the useful properties of seaweeds metabolites as potential agents for the prevention and therapy of influenza infection. MATERIALS AND METHODS: The sources of scientific literature were found in various electronic databases (i.e., PubMed, Web of Science, and ScienceDirect) and library search. The retrospective search depth is 25 years. RESULTS: Influenza is a serious medical and social problem for humanity. Recently developed drugs are quite effective against currently circulating influenza virus strains, but their use can lead to the selection of resistant viral strains. In this regard, new therapeutic approaches and drugs with a broad spectrum of activity are needed. Metabolites of seaweeds fulfill these requirements. This review presents the results of in vitro and in vivo experimental and clinical studies about the effectiveness of these compounds in combating influenza infection and explains the necessity of their use as a potential basis for the creation of new drugs with a broad spectrum of activity.

Evaluation of the antidepressant- and anxiolytic-like effects of a hydrophilic extract from the green seaweed Ulva sp. in rats.

OBJECTIVES: The green seaweed Ulva sp. contains a large amount of ulvans, a family of sulphated polysaccharides. The present study was designed to investigate in rats the antidepressant- and anxiolytic-like effects of a hydrophilic extract of Ulva sp. (MSP) containing about 45% of ulvans. METHODS: After a 14-day administration of MSP at doses of 10, 20 and 40 mg/kg/day, 48 and 60 male adult Wistar rats were respectively tested in the elevated plus-maze (EPM) and the forced swimming test (FST). In the FST, MSP effects were compared to the reference antidepressant drug imipramine (IMI) (10 mg/kg/day). Acute and sub-chronic toxicities of the extract were also assessed in male and female rats following OECD guidelines. RESULTS: MSP treatment did not modify anxiety-related behaviour in the EPM. In contrast, MSP induced a dose-dependent reduction of immobility behaviour in the FST. At the highest tested dose of 40 mg/kg, MSP displayed a significant antidepressant-like effect similar to IMI. MSP did not modify the exploratory behaviour of rats in the open field test and did not produce any toxic effect. DISCUSSION: MSP may potentially represent a good adjunct or alternative to existing antidepressant therapeutics. Further studies are necessary to confirm the mechanism of action of MSP and its modulation of brain functioning.

Bioactive carbohydrate polymers from marine sources as potent nutraceuticals in modulating obesity: a review.

The majority of bioactive polysaccharides are present in some marine creatures. These polysaccharides are considered as promising anti-obesity agents, their anti-obesity properties involve a number of mechanisms, including suppression of lipid metabolism and absorption, impact on satiety, and prevention of adipocyte differentiation. Obesity is linked to type 2 diabetes, cardiovascular disease, and other metabolic syndromes. In this review various bioactive polysaccharides like chitin, chitosan, fucosylated chondroitin sulphate, chitooligosaccharides and glycosaminoglycans have been discussed for their anti-obesity effects through various pathways. Critical evaluation of observational studies and intervention trials on obesity, lipid hypertrophy, dyslipidemia, and type 2 diabetes was done with a primary focus on specific marine fauna polysaccharide as a source of seafood that is consumed all over the world. It has been observed that consumption of individual seafood constituents was effective in reducing obesity. Thus, marine derived novel bioactive polysaccharides have potential applications in food and pharmaceutical industries.

Antidiabetic potentials of crude and purified sulphated polysaccharides isolated from Gracilaria gracilis, a seaweed from South Africa.

Over 90 % of all cases of diabetes that have been diagnosed are type 2 diabetes (T2D), a disease exacerbated by an increase in sedentary behaviour, bad eating habits, and obesity. This study investigated the antidiabetic properties of Gracilaria gracilis, using in vitro and ex vivo experimental models. The sulphated polysaccharides (SPs) from crude extracts of the seaweed powder was prepared via hot (100°C) and cold (25°C) aqueous extraction procedures before purification via an anion exchange chromatographic technique. Both the crude and purified extracts were characterised by Fourier-transform infrared spectroscopy (FT-IR), LC-MS analysis, and Nuclear Magnetic Resonance (NMR) spectroscopy. The crude cold-aqueous and purified hot-aqueous SPs from G. gracilis had the strongest α-glucosidase inhibitory effect with IC50 value of 0.15 and 0.07 mg/ml, respectively. The purified cold-aqueous SP was the most potent inhibitor of α-glucosidase with an IC50 value of 0.17 mg/ml. The crude and purified SP-rich extracts inhibited pancreatic lipase (hot aqueous SP = 0.03 mg/ml) activity and effectively stimulated glucose uptake in yeast cells. Moreover, they showed significantly (p < 0.05) better intestinal glucose absorption inhibitory properties at the highest concentration (1 mg/ml) and displayed significantly (p < 0.05) better muscle glucose uptake compared to the commercial antidiabetic drug, metformin, at the same concentration. Overall, the current findings indicate that G. gracilis SPs may inhibit carbohydrate-hydrolysing enzymes, limit the release of simple sugars from the gut whilst effectively stimulating the use of glucose by peripheral tissue thus may be suitable to develop antidiabetic food supplements after further animal and clinical trials.

Physiochemical changes, metabolite discrepancies of brown seaweed-derived sulphated polysaccharides in the upper gastrointestinal tract and their effects on bioactive expression.

Brown seaweed-derived polysaccharides, notably fucoidan and laminarin, are known for their extensive array of bioactivities and physicochemical properties. However, the effects of upper digestive tract modification on the bioactive performance of fucoidan and laminarin fractions (FLFs) sourced from Australian native species are largely unknown. Here, the digestibility and bioaccessibility of FLFs were evaluated by tracking the dynamic changes in reducing sugar content (CR), profiling the free monosaccharide composition using LC-MS, and comparing high-performance gel permeation chromatography profile variation via LC-SEC-RI. The effects of digestive progression on bioactive performance were assessed by comparing the antioxidant and antidiabetic potential of FLFs and FLF digesta. We observed that molecular weight (Mw) decreased during gastric digestion indicating that FLF aggregates were disrupted in the stomach. During intestinal digestion, Mw gradually decreased and CR increased indicating cleavage of glycosidic bonds releasing free sugars. Although the antioxidant and antidiabetic capacities were not eliminated by the digestion progression, the bioactive performance of FLFs under a digestive environment was reduced contrasting with the same concentration level of the undigested FLFs. These data provide comprehensive information on the digestibility and bioaccessibility of FLFs, and shed light on the effects of digestive progression on bioactive expression.

Relevance of the Extraction Stage on the Anti-Inflammatory Action of Fucoidans.

The anti-inflammatory action of fucoidans is well known, based on both in vitro and some in vivo studies. The other biological properties of these compounds, their lack of toxicity, and the possibility of obtaining them from a widely distributed and renewable source, makes them attractive novel bioactives. However, fucoidans' heterogeneity and variability in composition, structure, and properties depending on seaweed species, biotic and abiotic factors and processing conditions, especially during extraction and purification stages, make it difficult for standardization. A review of the available technologies, including those based on intensification strategies, and their influence on fucoidan composition, structure, and anti-inflammatory potential of crude extracts and fractions is presented.

Bioactive Polysaccharides from Microalgae: A Close Look at the Biomedical Applications.

There is a current tendency towards bioactive natural products that can be used in different areas such as food, pharmaceutical, and biomedical. In the last decades, polysaccharides have attracted increasing interest because of their potent nontoxic effects, therapeutic properties, and diversified range of applications. Polysaccharides are complex and heterogeneous macromolecules constituted of different monosaccharides and, in some cases, of glucuronic acid and sulphate groups. Polysaccharides with biological activity can be derived from plants, animals and microorganisms, especially microalgae. Microalgae are considered one of the most promising sources of these compounds that have already proved to have several important biological properties. In this sense, our objective is to elucidate the use of bioactive polysaccharides from microalgae in biomedical applications, emphasizing the biological activity of these compounds. Furthermore, the microalgal biomass production systems and polysaccharides extraction methods were presented and discussed.

Bioprospection of Antiviral and Antitumor Compounds from Some Marine Algae from Egyptian Shores.

BACKGROUND: The marine algae are considered a diverse source of bioactive compounds. Many active compounds have been isolated from algae and show good biological activities. MATERIALS AND METHODS: The aim of this study is to detect the antiviral and anticancer activities in some extracts of marine algae. Extraction, purification and identification of some marine algae common in Egypt were conducted. Extraction of Ulva lactuca, Sargassum dentifolium, and Cystoseiara myrica was conducted. A sequence of extractions, including extraction by ethanol, boiling water, hydrochloric acid and sodium hydroxide were carried out. The obtained extracts were evaluated for their antitumour and antiviral activities against liver tumour cells, brain tumour cell lines, measles virus, mumps virus and hepatitis B virus (HBV). The extracts of the best activities were subjected for purification by size exclusion chromatography and anion exchange chromatography for ethanolic extracts or precipitation by cetylpyridinium chloride (CPC) then by size exclusion chromatography and anion exchange chromatography for aqueous extracts. Separation by GLS/MS was performed. The structures of the active compounds have been identified through different chemical analyses, including sugar analysis, configurational analysis, High-Performance Liquid Chromatography (HPLC), infrared spectroscopy (IR), Gas-Liquid Chromatography-Mass Spectroscopy (GLC-MS) and 1H,13C nuclear magnetic resonance (NMR) at ZV. RESULTS: The active compounds from the water extracts have been identified mainly as polysaccharides and sulphated polysaccharides. The antitumour and the antiviral activities of ethanolic extracts are attributable to compound identified as Ethyl Palmitate. These natural compounds did not show cytotoxic effect. CONCLUSION: These outputs could be preliminary for further biological studies aiming to therapeutic application.

Sulphated modification of a polysaccharide obtained from fresh persimmon (Diospyros kaki L.) fruit and antioxidant activities of the sulphated derivatives.

Free radicals and other reactive oxygen species (ROS) are believed to play significant roles in ageing as well as in a number of degenerative or pathological diseases. This paper reports the preparation, characterisation and potential antioxidant activity of a type of chemically sulphated polysaccharide isolated from fresh persimmon (Diospyros kaki L.) fruit. Three sulphated derivatives with variable degrees of substitution (0.8, 1.7 and 2.5) were obtained by the chlorosulphonic acid-pyridine method. The sulphated derivatives all showed dose-dependent reducing power and free radical scavenging effect of 1,1-dipheny-l-2-picrylhydrazyl, superoxide anion and hydroxyl. Our results showed that the sulphated modification of polysaccharides significantly increased their antioxidant activities and may be an effective way to prepare these valuable derivatives.

Physicochemical characterization and antioxidant activity of sulphated polysaccharides derived from Porphyra haitanensis.

This study was designed to fully characterize Porphyra haitanensis polysaccharides, and to evaluate their antioxidant activity. The polysaccharides primarily contained galactose and 3,6-anhydrogalactose in a molar ratio of 1.2:1.0, respectively and sulfate content about 3.8%. The molecular weight of polysaccharides is 2.5 × 105 Da. Scanning electron microscopy and atomic force microscopy of the polysaccharides pointed towards an irregular network with more or less hexagonal and a few rectangular pores. The chemical structure was confirmed through Fourier transform infrared spectroscopy, and 1D and 2D nuclear magnetic resonance structural characterization wherein â†’ 4-3,6-anhydro-α-L-galactopyranose-(1 â†’ 3)-ß-D-galactopyranose segments. The extracted polysaccharides revealed relatively high 2, 2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid radical scavenging activity (53.16% at 2 mg/mL), moderate 2,2-diphenyl-1-picrylhydrazyl radical scavenging efficacy (34.63% at 2 mg/mL), and low hydroxyl radical scavenging potential (23.80% at 2 mg/mL). Further purification of these polysaccharides, hence, is advised for their potential role as antioxidants in the food, pharmaceutical and cosmeceutical industry.

Seaweed polysaccharides as macromolecular crowding agents.

Development of mesenchymal stem cell-based tissue engineered implantable devices requires prolonged in vitro culture for the development of a three-dimensional implantable device, which leads to phenotypic drift, thus hindering the clinical translation and commercialisation of such approaches. Macromolecular crowding, a biophysical phenomenon based on the principles of excluded-volume effect, dramatically accelerates and increases extracellular matrix deposition during in vitro culture. However, the optimal macromolecular crowder is still elusive. Herein, we evaluated the biophysical properties of various concentrations of different seaweed in origin sulphated polysaccharides and their effect on human adipose derived stem cell cultures. Carrageenan, possibly due to its high sulphation degree, exhibited the highest negative charge values. No correlation was observed between the different concentrations of the crowders and charge, polydispersity index, hydrodynamic radius and fraction volume occupancy across all crowders. None of the crowders, but arabinogalactan, negatively affected cell viability. Carrageenan, fucoidan, galactofucan and ulvan increased extracellular matrix (especially collagen type I and collagen type V) deposition. Carrageenan induced the highest osteogenic effect and galactofucan and fucoidan demonstrated the highest chondrogenic effect. All crowders were relatively ineffective with respect to adipogenesis. Our data highlight the potential of sulphated seaweed polysaccharides for tissue engineering purposes.

The COVID 19 novel coronavirus pandemic 2020: seaweeds to the rescue? Why does substantial, supporting research about the antiviral properties of seaweed polysaccharides seem to go unrecognized by the pharmaceutical community in these desperate times?

Presently, there is lack of a vaccine that would lead to immunization against the virus COVID-19, but here are some of the characteristics that various seaweeds have and which may provide a glimpse into potential solutions of this global health problem in the near future and possibly forearm us for any future such pandemics. Many species of marine algae contain significant quantities of complex structural sulphated polysaccharides that have been shown to inhibit the replication of enveloped viruses. Other compounds, both of red algae (e.g., the lectin griffithsin and the phycocolloid carrageenan), and other sulphated polysaccharides extracted from green algae (i.e., ulvans) and brown algae (i.e., fucoidans) could be potential antiviral therapeutic agents against SARS-CoV-2.

Structural analysis and potential immunostimulatory activity of Nannochloropsis oculata polysaccharides.

The relevance of microalgae biotechnology for producing high-value compounds with biomedical application, such as polysaccharides, has been increasing. Despite this, the knowledge about the composition and structure of microalgae polysaccharides is still scarce. In this work, water-soluble polysaccharides from Nannochloropsis oculata were extracted, fractionated, structurally analysed, and subsequently tested in terms of immunostimulatory activity. A combination of sugar and methylation analysis with interaction data of carbohydrate-binding proteins using carbohydrate microarrays disclosed the complex structural features of the different polysaccharides. These analyses showed that the water-soluble polysaccharides fractions from N. oculata were rich in (ß1→3, ß1→4)-glucans, (α1→3)-, (α1→4)-mannans, and anionic sulphated heterorhamnans. The immunostimulatory assay highlighted that these fractions could also stimulate murine B-lymphocytes. Thus, the N. oculata water-soluble polysaccharides show potential to be further explored for immune-mediated biomedical applications.

Deciphering the anti-Parkinson's activity of sulphated polysaccharides from Chlamydomonas reinhardtii on the α-Synuclein mutants A30P, A53T, E46K, E57K and E35K.

Parkinsonism-linked mutations in alanine and glutamic acid residues of the pre-synaptic protein α-Synuclein (α-Syn) affect specific tertiary interactions essential for stability of the native state and make it prone to more aggregation. Many of the currently available drugs used for the treatment of Parkinson's disease (PD) are not very effective and are associated with multiple side effects. Recently, marine algae have been reported to have sulphated polysaccharides which offers multiple pharmaceutical properties. With this background, we have isolated sulphated polysaccharides from Chlamydomonas reinhardtii (Cr-SPs) and investigated their effects on inhibition of fibrillation/aggregation of α-Syn mutants through a combination of spectroscopic and microscopic techniques. The kinetics of α-Syn fibrillation establishes that Cr-SPs are very effective in inhibiting fibrillation of α-Syn mutants. The morphological changes associated with the fibrillation/aggregation process have been monitored by transmission electron microscopy. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis gel image suggests that Cr-SPs increase the amount of soluble protein after completion of the fibrillation/aggregation process. The circular dichroism results showed that Cr-SPs efficiently delay the conversion of native protein into ß-sheet-rich structures. Thus, the current work has considerable therapeutic implications towards deciphering the potential of Cr-SPs to act against PD and other protein aggregation-related disorders.

Upgrading the antioxidant properties of fucoidan and alginate from Cystoseira trinodis by fungal fermentation or enzymatic pretreatment of the seaweed biomass.

The seaweed Cystoseira trinodis was fermented by different fungi prior to extraction of fucoidan and alginate to enhance their antioxidative potential. All the investigated fungi were able to produce fucoidanase (1.05-3.41 U/ml) and alginate lyase (7.27-18.59 U/mL). Different fungal species induced a reduction in the molecular weight (MW) of fucoidan and alginate in comparison to the unfermented control. The MW of fucoidan reduced by 41-81.5%, while the MW of alginate was reduced by 28-75%, depending on the fungal species. Significant increases in the fucose and sulphate contents of fucoidan and mannuronic/guluronic acid ratio of alginate were induced by fungal fermentation. Fungal pretreatment enhanced the ferric reducing antioxidant power, total antioxidant capacity and hydroxyl radical scavenging activity of both fucoidan and alginate. Additionally, enzymatic pretreatment of the macroalgal biomass assisted in the recovery of fucoidan and alginate with low molecular weight and enhanced antioxidative potential.