Determination of physicochemical properties of sulphated fucans from sporophyll of Undaria pinnatifida using light scattering technique

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.

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.

Modulation of toxicity effects of CuSO4 by sulfated polysaccharides extracted from brown algae (Sargassum tenerrimum) in Danio rerio as a model

Copper is widely used in agriculture and aquaculture due to its high disinfection properties and relatively low cost. However, the increase in copper concentration due to evaporation can lead to water reservoir pollution, which can harm the health of consumers. The present study aimed to determine the role of sulfated polysaccharides (SPs) extracted from Sargassum tenerimum algae in reducing lesions caused by the heavy metal copper. Zebrafish (Danio rerio) were used as a human model in five treatments. The negative and positive control groups were fed a diet containing zero percent of SPs, while the experimental groups were fed 0.5%, 1%, and 1.5% of SPs in three treatments for 56 days, finally CuSO4 was exposed only to the positive control group and the groups fed with SPs. Results showed a significant decrease in the activity level of ALT enzymes (39-16 U/mL), AST (67-46 U/mL), and ALP (485-237 U/mL), confirming the results obtained from histopathological studies in CuSO4 exposed groups. The addition of SPs to the diet resulted in a significant reduction (sig < 0.05) of mortalities due to the decrease of tissue damage. Additionally, due to the anti-inflammatory properties and the protective effect of SPs, a significant decrease (sig < 0.05) was observed in the relative expression of Il-1β and Tnf-α genes.

Studying the shelf life of butter containing fucoidan, by evaluating sensory and chemical properties

Fucoidan powder was added in amounts of 0.05, 0.1,0.3, and 0.5% to sour cream butter and sensory and chemical properties were tested on their shelf life for 60 days during storage. Peroxide levels initially increased until day 40 of storage and then decreased. Butter samples from the control group had the highest amount of peroxide on day 40 (15.25 ± 1.41 meq/kg butter), while samples treated with fucoidan 0.5% had the lowest amount of peroxide (6.35 ± 0.53 meq/kg butter). The acidity of butter treatments increased during storage (p < .05). Butter samples from the control group had the highest acidity at 60 days of storage (0.40 ± 0.033 mg KOH / g butter), while samples treated with 0.5% fucoidan had the lowest acidity (0.17 ± 0.013 mg KOH / g butter). The treated butter samples showed the highest stability. Fucoidan, as an antioxidant, reduces the taste, odor, and discoloration of butter added with fucoidan during storage because it completely removes odorless tasteless powder, and the free radical chain is involved in oxidation and improves product properties. The results showed that there are no significant changes in the acceptance rate of butter treated with fucoidan during 60 days of storage in the refrigerator (p > .05). The sensory scores of the treated butter showed that the sensory properties during the storage period were similar to the control samples, but on day 40 of storage, they decreased. In general, a concentration of 0.5% fucoidan delays the oxidative process and increases shelf life and is selected as a superior treatment in terms of sensory evaluation, and is introduced as a functional food.

Marine collagen-chitosan-fucoidan/chondroitin sulfate cryo-biomaterials loaded with primary human cells envisaging cartilage tissue engineering

Cartilage repair after a trauma or a degenerative disease like osteoarthritis (OA) continues to be a big challenge in current medicine due to the limited self-regenerative capacity of the articular cartilage tissues. To overcome the current limitations, tissue engineering and regenerative medicine (TERM) and adjacent areas have focused their efforts on new therapeutical procedures and materials capable of restoring normal tissue functionalities through polymeric scaffolding and stem cell engineering approaches. For this, the sustainable exploration of marine origin materials has emerged in the last years as a natural alternative to mammal sources, benefiting from their biological properties (e.g., biocompatibility, biodegradability, no toxicity, among others) for the development of several types of scaffolds. In this study, marine collagen(jCOL)-chitosan(sCHT)-fucoidan(aFUC)/chondroitin sulfate(aCS) were cryo-processed (-20 °C, -80 °C, and -196 °C) and a chemical-free crosslinking approach was explored to establish cohesive and stable cryogel materials. The cryogels were intensively characterized to assess their oscillatory behavior, thermal structural stability, thixotropic properties (around 45 % for the best formulations), injectability, and surface structural organization. Additionally, the cryogels demonstrate an interesting microenvironment in in vitro studies using human adipose-derived stem cells (hASCs), supporting their viability and proliferation. In both physic-chemical and in vitro studies, the systems that contain fucoidan in their formulations, i.e., C₁ (jCOL, sCHT, aFUC) and C₃ (jCOL, sCHT, aFUC, aCS), submitted at -80 °C, are those that demonstrated most promising results for future application in articular cartilage tissues.

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.

Comparison of in vitro and in vivo antioxidant activities of commercial fucoidans from Macrocystis pyrifera, Undaria pinnatifida, and Fucus vesiculosus

Antioxidants fucoidans from three seaweeds, Undaria pinnatifida (FUP), Macrocystis pyrifera (FMP) and Fucus vesiculosus (FFV) are sold commercially. However, it is unclear which fucoidan is the most potent antioxidant. Therefore, our objective was to compare the antioxidant activities of these fucoidans. For this purpose, six in vitro antioxidant tests were used, total antioxidant capacity, hydroxyl radical scavenging assay, ferrous and cupric chelating assay, reducing power and H2O2 scavenging assay. The data showed that the fucoidans had a low capacity to donate electrons, and a low capacity to chelate metals. The best activity obtained was in the scavenging of hydroxyl radical. When macrophages were exposed to H2O2 and fucoidans, MTT and live/dead assays showed that all fucoidans protected cells from oxidative damage. The survival rate of zebrafish embryos was significantly higher when exposed to H2O2 and fucoidans than H2O2 alone. In summary, the fucoidans evaluated were ranked according to their antioxidant activity as follows: FMP > FFV > FUP, and the results suggest that these fucoidans, mainly FMP, can be used in the formulation of medicines/foods.

Characterization and hypoglycemic effects of sulfated polysaccharides derived from brown seaweed Undaria pinnatifida

The brown seaweed Undaria pinnatifida polysaccharides show various biological activities, but their hypoglycemic activity and the underlying mechanism remain unclear. Here, three fractions of sulfated polysaccharides Up-3, Up-4, and Up-5 were prepared by microwave-assisted extraction from U. pinnatifida. In vitro assays demonstrated that Up-3 and Up-4 had strong α-glucosidase inhibitory activity, and Up-3, Up-4, and Up-5 could improve the glucose uptake in insulin-resistant HepG2 cells without affecting their viability. In vivo studies indicated Up-3 and Up-4 markedly reduced postprandial blood glucose levels. Up-U (a mixture of Up-3, Up-4, and Up-5), reduced fasting blood glucose levels, increased glucose tolerance and alleviated insulin resistance in HFD/STZ-induced hyperglycemic mice. Histopathological observation and hepatic glycogen measurement showed that Up-U alleviated the damage of the pancreas islet cell, reduced hepatic steatosis, and promoted hepatic glycogen synthesis. These findings suggest that Up-U could alleviate postprandial and HFD/STZ-induced hyperglycemia and was a potential agent for diabetes treatment.

Fucoidan from Ecklonia maxima is a powerful inhibitor of the diabetes-related enzyme, α-glucosidase

Ecklonia maxima, an endemic South African seaweed, is a potential source of beneficial bioactive compounds. Among these compounds, fucoidan, a sulphated polysaccharide has a wide range of bioactivities including anti-diabetic activity. In this study, fucoidan was extracted from E. maxima by the hot water extraction method and then characterised by colorimetric assays for sugar composition. The extraction from E. maxima yielded 6.89% fucoidan which was found to contain 4.45 ± 0.25% L-fucose and 6.01 ± 0.53% sulphate. The water extracted E. maxima fucoidan had a low molecular weight of approximately 10 kDa. Structural studies (FT-IR, NMR and XRD) confirmed the structure and integrity of the fucoidan to be similar to previously studied fucoidans in literature. Finally, the activities of starch digestive enzymes; α-amylase and α-glucosidase, were investigated in the presence of the E. maxima fucoidan extract. Fucoidan from E. maxima was observed to be a potent mixed-type inhibitor of α-glucosidase with an IC50 range of 0.27-0.31 mg.ml-1, which was significantly lower than the commercial anti-diabetic standard, acarbose. Our present study demonstrated that fucoidan from E. maxima is a more powerful inhibitor compared to some standard anti-diabetic compounds and thus shows great potential for managing type 2 diabetes.

Sulfated Polysaccharides from Macroalgae for Bone Tissue Regeneration

BACKGROUND

Utilization of macroalgae has gained much attention in the field of pharmaceuticals, nutraceuticals, food and bioenergy. Macroalgae has been widely consumed in Asian countries as food from ancient days and proved that it has potential bioactive compounds which are responsible for its nutritional properties. Macroalgae consists of a diverse range of bioactive compounds including proteins, lipids, pigments, polysaccharides, etc. Polysaccharides from macroalgae have been utilized in food industries as gelling agents and drug excipients in the pharmaceutical industries owing to their biocompatibility and gel forming properties. Exploration of macroalgae derived sulfated polysaccharides in biomedical applications is increasing recently.

METHODS

In the current review, we have provided information of three different sulfated polysaccharides such as carrageenan, fucoidan and ulvan and their isolation procedure (enzymatic precipitation, microwave assisted method, and enzymatic hydrolysis method), structural details, and their biomedical applications exclusively for bone tissue repair and regeneration.

RESULTS

From the scientific results on sulfated polysaccharides from macroalgae, we conclude that sulfated polysaccharides have exceptional properties in terms of hydrogel-forming ability, scaffold formation, and mimicking the extracellular matrix, increasing alkaline phosphatase activity, enhancement of biomineralization ability and stem cell differentiation for bone tissue regeneration.

CONCLUSION

Overall, sulfated polysaccharides from macroalgae may be promising biomaterials in bone tissue repair and regeneration.

Attenuation of oxidative stress induced mitochondrial dysfunction and cytotoxicity in fibroblast cells by sulfated polysaccharide from Padina gymnospora

In this present study, isolation, characterization and protective effect of sulfated polysaccharide (SP) isolated from the brown algae Padina gymnospora was investigated. SP was isolated and characterized through FT-IR, 1H NMR, TGA, GC-MS and CHN analysis. The molecular weight of SP was found to be 16 kDa. The isolated SP contains 29.4 ± 0.35% of sulfate, 27 ± 0.11% of fucose, 0.05 ± 0.12% of protein, respectively. Furthermore, SP exhibits its excellent radical scavenging effects were evaluated by DPPH, ABTS radical scavenging and reducing power assays. Moreover, pretreatment with SP significantly mitigates H2O2 induced cytotoxicity in L-929 cells in a dose dependent manner. Furthermore, SP pretreatment ameliorates oxidative stress induced apoptosis and DNA damage, alleviates the generation of intracellular reactive oxygen species (ROS) and restores mitochondrial membrane potential (MMP) in L-929 cells through its antioxidant potential. Together, these results suggest that SP can be exploited as a natural antioxidant in the food and pharmaceutical industries.

Sulfated polysaccharide from Sargassum tenerrimum attenuates oxidative stress induced reactive oxygen species production in in vitro and in zebrafish model

The sulfated polysaccharide (SP) was isolated from the brown alga S. tenerrimum. The chemical composition of SP composed of 57 ± 0.29% of total sugar, 1.14 ± 0.28% of protein and 25.6 ± 0.45% of sulfate. Elemental analysis of SP shows 28.8% of carbon, 4.02% of hydrogen and 0.29% of nitrogen. The molecular weight of SP was estimated as 31 kDa. Further, the SP was characterized through FT-IR, 1H-NMR, GC-MS, XRD and TGA analysis. The DPPH and ABTS radical scavenging activity of SP showed 34.03-62.70% and 22.94-38.04% at the concentration of 25-125 μg/mL respectively. In addition, SP exerted a protective role against H2O2 mediated oxidative stress in fibroblast cells through scavenging intracellular ROS. Furthermore, ROS generation and cell death were significantly decreased in SP treated zebrafish embryos at 150 μg/mL, whereas the survival rate was increased. The protective effect of SP against oxidative stress might be utilized in pharmacological industries.

Fucoidan Extracted from the New Zealand Undaria pinnatifida-Physicochemical Comparison against Five Other Fucoidans: Unique Low Molecular Weight Fraction Bioactivity in Breast Cancer Cell Lines

Fucoidan, the complex fucose-containing sulphated polysaccharide varies considerably in structure, composition, and bioactivity, depending on the source, species, seasonality, and extraction method. In this study, we examined five fucoidans extracted from the same seaweed species Undaria pinnatifida but from different geological locations, and compared them to the laboratory-grade fucoidan from Sigma (S). The five products differed in molecular composition. The amount of over 2 kDa low molecular weight fraction (LMWF) of the New Zealand crude fucoidan (S1) was larger than that of S, and this fraction was unique, compared to the other four fucoidans. The difference of molecular compositions between S and S1 explained our previous observation that S1 exhibited different anticancer profile in some cancer cell lines, compared with S. Since we observed this unique LMWF, we compared the cytotoxic effects of a LMWF and a high molecular weight fucoidan (HMWF) in two breast cancer cell lines-MCF-7 and MDA-MB-231. Results indicated that the molecular weight is a critical factor in determining the anti-cancer potential of fucoidan, from the New Zealand U. pinnatifida, as the LMWF exhibited a dose-dependent inhibition on the proliferation of breast cancer cells, significantly better than the HMWF, in both cell lines. A time-dependent inhibition was only observed in the MCF-7. Induction of caspase-dependent apoptosis was observed in the MDA-MB-231 cells, through the intrinsic apoptosis pathway alone, or with the extrinsic pathway. LMWF stimulated a dose-dependent NOS activation in the MDA-MB-231 cells. In conclusion, the fucoidan extracted from the New Zealand U. pinnatifida contains a unique LMWF, which could effectively inhibit the growth of breast cancer cell lines. Therefore, the LMWF from New Zealand U. pinnatifida could be used as a supplement cancer treatment.

Improved immunomodulatory and antioxidant properties of unrefined fucoidans from Sargassum angustifolium by hydrolysis

The effect of polymer degradation was studied on immunomodulatory and antioxidant properties of fucoidan isolated from S. angustifolium. Partially hydrolyzed fucoidans were prepared using 0.01 N hydrochloric acid after incubation for 10 and 15 min in boiling water. FT-IR analysis showed two major peaks at 850 cm^-1 corresponding to bending vibration of C-O-S of sulfate and 1256 cm^-1 derived from the stretching vibration of S-O. The native fucoidan consisted mainly of carbohydrate (49.4%), sulfate (22.9%), uronic acid (10.3%) and minor amount of protein (4.1%). The hydrolysis reduced the molecular weight of native fucoidan from 421 × 10³ g/mol to 104.1 × 10³ g/mol after 10 min boiling and 63.9 × 10³ g/mol after 15 min boiling, without a significant change in their chemical compositions. Acid degradation increased the specific volume of gyration from 0.84 to 3.32 cm³/g in hydrolyzed fucoidan polymers. Fucoidan with the lowest molecular weight showed the greatest proliferating effect on RAW264.7 cells and induced the macrophage cells to release more nitric oxide (39.0 μmol) at 50 μg/mL. The DPPH radical scavenging activity, ABTS radical scavenging activity and reducing power remarkably increased after hydrolysis. The current results showed that molecular weight has determinant effect on immunomodulatory and antioxidant activities of unrefined fucoidan and thus acid hydrolysis can be applied on commercial scale to obtain fucoidans with more beneficial effects.

Cytotoxic effect of fucoidan extracted from Sargassum cinereum on colon cancer cell line HCT-15

The present study was aimed to investigate the antioxidant and cytotoxicity activity against HCT-15 of fucoidan from Sargassum cinereum. Purification of fucoidan was done by DEAE cellulose and dialysis. Physicochemical characterization of fucoidan was analysed by calorimetric assay, FT-IR, HPLC and NMR. The extracted fucoidan contains 65.753% of fucose and 3.7±1.54% of sulphate respectively. HPLC results showed that the fucoidan contains the monosaccharide composition such as fucose, galactose, mannose and xylose. Antioxidant effect of fucoidan in Sargassum Cinereum was determined by DPPH. The maximum DPPH activity was found at the concentration of 100μg, where as the crude extract showed the scavenging activity was 63.58±0.56%. Cytotoxicity effect was done by MTT assay. Fucoidan extract caused about 50% of cell death after 24h of incubation with 75±0.9037μg/ml against HCT-15.

Fucoidan - An α-amylase inhibitor from Sargassum wightii with relevance to NIDDM

The present experiment was conducted to screen the α-amylase inhibitory activity of fucoidan extracted from Sargassum wightii collected at the coastal area of Mandapam, Tamil Nadu, India. Fucoidan was extracted from the sporophyll of S. Wightii by ethanol and CaCl2 precipitation method. The average yield was 1.8±0.16% and the extracted fucoidan was found to contain 53±0.52% of fucose and 36±0.60% of sulphate. Structural elucidation (FT-IR and NMR) and in vitro α-amylase activity of purified fucoidon were performed. Fucoidan at the concentration of 62.5, 125 and 250μg exhibited 24.81, 62.50 and 99.24% inhibition against α-amylase, respectively, in a dose dependent manner. Fucoidan from S. wightii also inhibits α-glucosidase which clearly indicates dual inhibitory activity of the compound. The IC50 value against α-amylase of fucoidan is found to be 103.83μg which is more effective than that of acarbose (16mg).

Fucoidan--a α-D-glucosidase inhibitor from Sargassum wightii with relevance to type 2 diabetes mellitus therapy

The present study was conducted to screen the α-d-glucosidase inhibitory activity of fucoidan extracted from Sargassum wightii collected at Mandapam coastal area, Tamil Nadu, India. Fucoidan was extracted from the sporophyll of S. wightii using ethanol, acetone and CaCl2 precipitation. The average yield was 1.8 ± 0.16% and the extracted fucoidan was found to contain 53 ± 0.52% of fucose and 36 ± 0.60% of sulphate. FT-IR, NMR and in vitro α-d-glucosidase activity of purified fucoidan were performed. Fucoidan at the concentration of 31.25, 62.5, 125 and 250 μg exhibited 19, 31, 38 and 71% inhibition against α-d-glucosidase respectively in a dose dependent manner. The IC50 value against α-D-glucosidase of fucoidan is found to be 132.9 μg which is more effective than that of acarbose (1mg). The diverse biological activities of Fucoidan include anticancer, anti inflammatory and antimicrobial but the α-d-glucosidase inhibitory activity of native fucoidan from S. wightii for type 2 diabetes therapy is first of its kind.

Molecular characterization and immunomodulatory activity of sulfated fucans from Agarum cribrosum

The sulfated-fucans, known as fucoidans, were isolated from Agarum cribrosum and fractionated using ion-exchange chromatography to determine their molecular characteristics and in vitro immunomodulatory activity. The crude and fractionated fucoidans (F1 and F2) consisted mostly of carbohydrates (52.4-56.0%), sulfates (12.7-23.0%) and uronic acid (14.1-21.8%), with a small amount of proteins (3.9-9.3%), and included various levels of fucose (44.0-46.7%), mannose (18.9-26.8%), galactose (16.8-33.0%), xylose (10.7-17.0%) and glucose (3.5-9.5%). The crude and fractionated fucans contained one or two subfractions with average molecular weights (Mw) ranging from 110.1 × 10(3) to 2420 × 10(3)g/mol. The fractionated fucoidan, especially the F1 fraction, strongly stimulated murine macrophages (Raw 264.7 cells), producing a considerable amount of nitric oxide (NO) and inducing expression of inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2) and interleukin-10 (IL-10) transcripts by activation of nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) pathways. The maximally immunoenhancing F1 fraction was mainly composed of (1 → 3)-linked fucose, (1 → 2)-linked mannose and (1 → 4)-linked glucuronic acid with sulfates at C-2 or both the C-2 and C-4 positions in (1 → 2,3)- and (1 → 2,3,4)-linked fucose residues.

Structural characterisation of algae Costaria costata fucoidan and its effects on CCl₄-induced liver injury

Fucoidan is a well-known natural product that is commonly found in brown algae and shows a variety of activities, including immunomodulation, antioxidation, and the combat of carcinogens. The fucoidan fractions of Costaria costata, a brown algae introduced from Japan and cultured in northern China, were studied. The fucoidan fractions were extracted, separated, and purified using a combinatorial procedure consisting of enzymolysis, ethanol precipitation, and DEAE and size-exclusion chromatographies. The fundamental characteristics of the four enriched fucoidan fractions (F1-F4), such as their sulphate content and monosaccharide composition, were investigated. FTIR and NMR spectroscopy were employed to further elucidate the structural features of the four fractions. It was found that the F1-F4 fractions all showed oxidative activity against hydroxyl radicals. The bioactive effects of the fucoidan fractions on CCl4-induced liver injury suggest their potential use as ingredients for functional foods or pharmaceuticals.

The effect of fucoidan from brown seaweed Sargassum wightii on WSSV resistance and immune activity in shrimp Penaeus monodon (Fab)

The polysaccharide-fucoidan was extracted from brown seaweed Sargassum wightii and characterized through FT-IR and (13)C &(1)H NMR analysis. The extracted fucoidan was supplemented with pellet diets at three different concentrations (0.1, 0.2 and 0.3%). The fucoidan supplemented diets were fed to Penaeus monodon for 45 days, then challenged with WSSV and the mortality percentage was recorded daily up to 21 days. During the challenge test, the control group showed 100% mortality within 10 days, but in the experimental groups, the mortality percentage (51-72% within 21 days) was decreased considerably (P < 0.05) with respect to the concentrations of fucoidan. The reduction in mortality percentage of experimental groups over control group was ranged from 50.81 to 68.06%. During challenge experiment, the immunological parameters such as THC, prophenoloxidase activity, respiratory burst activity, superoxide dismutase activity and phagocytic activity were measured before injection of WSSV (0 day) and after the injection of WSSV on 10th and 21st days, respectively. All the immunological parameters of experimental groups were significantly (P < 0.05) increased than control group. RT-PCR analysis confirmed the considerable reduction of WSSV DNA copy numbers with respect to the concentration of fucoidan. It was concluded that P. monodon fed with fucoidan of S. wightii supplemented diet had enhanced the innate immunity and increased resistance against WSSV infection.

The effect of ultrasonificated extracts of Spirulina maxima on the anticancer activity

The effect of ultrasonic extraction on extraction yields, cytotoxicity, and anticancer activity of Spirulina maxima was investigated in this study. Optimal extraction conditions were determined as 60 kHz frequency at 60°C for 30 min with 120 W intensity, which resulted in 19.3% of extraction yields and 19.1% of cytotoxicity on normal human cells. Yields from conventional water and ethanol extraction were 15.8% at 100°C and 8.3% at 80°C, respectively. It was found that the extracts obtained by ultrasonic extraction process selectively inhibited the digestive-related cancer cell lines, such as human stomach cancer cells, having 89% of the highest inhibition ratio and 4.5 of the highest selectivity. In adding 0.5 mg/mL of the extract, human promyelocytic leukemia cells' cell differentiation was increased 1.72 times over that of the control. Expression level of B cell lymphoma-2 from Hep3B cell was also effectively suppressed by the extract obtained at 60 kHz and 60°C, leading to the inhibition of the early step of carcinogenesis. This work suggests that anticancer activity of the extracts is due to water-soluble polysaccharides rather than proteins and is further supported by the result that the ultrasonification extraction process can efficiently extract relatively intact polysaccharides rather than digesting the proteins in S. maxima by matrix assisted laser desorption ionization-time of flight and high performance size exclusion chromatography chromatogram analyses. Therefore, ultrasonic extraction increases both extraction yield and the biological activity of S. maxima extracts, which might be useful as an alternative natural anticancer agent in the medical and food industries.

Effects of molecular weight and hydrolysis conditions on anticancer activity of fucoidans from sporophyll of Undaria pinnatifida

Hydrolyzed fucoidans, from sporophyll of Undaria pinnatifida, were used to determine the effects of molecular weight (Mw) and hydrolysis conditions on cancer cell growth. Native fucoidans showed anticancer activity of 37.6%. When hydrolyzed in boiling water with HCl for 5 min, fucoidans (Mw = 490 kDa) significantly increased anticancer activity to 75.9%. However, fucoidans hydrolyzed in a microwave oven showed little improvement of anticancer activity and even exhibited the inhibition activity below 30% when treated more than 90s. This suggests that anticancer activity of fucoidans could be significantly enhanced by lowering their Mw only when they are depolymerized by mild condition.