• Korean Chemical Engineering Research
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• v.58 no.1
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• pp.59-63
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• 2020

Radical scavenger is used to improve the durability of PEMFC polymer membrane. In this study, we investigated whether fucoidan extracted from seaweed as a radical scavenger prevents electrochemical degradation through Fenton and OCV Holding experiments. Fucoidan has an antioxidant effect, protecting the polymer membrane from hydrogen peroxide and oxygen radicals, reducing the degradation rate to 1/10. Fucoidan has been shown to be more effective than MnO₂, which is used as a radical scavenger. In the PEMFC cell, the accelerated durability evaluation method (OCV Holding) showed that fucoidan reduced the hydrogen permeability of the polymer membrane by 12% and enhanced the performance by 29.1% compared to without radical scavenger. And fucoidan was found to be more effective in the cathode side ionomer than the anode side.

• Polymer(Korea)
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• v.35 no.4
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• pp.332-336
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• 2011

Hydrogels have been investigated due to their potential in a myriad of applications. The introduction of functional moiety such as sulfide has expanded their applicability. In this study, an investigation was carried out on the introduction of fucoidan into the hydrogels of clay/acrylamide. In the resulting semi-IPN nanocomposite hydrogels, the linear polysaccharide, fucoidan, has strong ionic interactions with clay. It was also confirmed from simple mixing tests that fucoidan can physically crosslink with clay without chemical crosslinks. In the semi-IPN hydrogels, equilibrium swelling ratio increased with the content of fucoidan. Elastic modulus increased with an initial increase in the content of fucoidan, and decreased with a further increase. The work of fracture results of these hydrogels showed their tough properties. These hydrogels could provide functional properties such as mucoadhesiveness with tunable hydrogel characteristics.

• Korean Journal of Clinical Laboratory Science
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• v.49 no.4
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• pp.323-328
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• 2017

Angiogenesis is a process including members of the angiogenic factors. In particular, fibroblast growth factor 2 (FGF2) is considered the most potent angiogenic factor because it promotes cell proliferation and tube formation. A recent study reported that fucoidan derived from marine plant potentiated FGF-2 induced tube formation in human endothelial cells. On the other hand, the molecular mechanisms involved in the angiogenic activity of fucoidan and FGF2 are unknown. In this study, a fucoidan treatment promoted angiogenesis induced by FGF2. The effects of fucoidan on FGF2-induced angiogenesis were confirmed by a proliferation assay using a CellTiter96 Aqueous One solution after a treatment with fucoidan and FGF2. The tube formation and wound healing assay for the angiogenic activity were also confirmed. Reverse transcription PCR showed a change in the mRNA of vascular endothelial growth factor-A (VEGF-A), intercellular adhesion molecule-1 (ICAM-1), matrix metallopeptidase9 (MMP9), and the signal transducer and activator of transcription3 (STAT3). In summary, the Fucoidan/FGF2 treatment induced an increase in cell proliferation, improved the tube formation and wound healing activity, and altered the STAT3, VEGF-A, ICAM-1, and MMP9 mRNA expression levels. Further research will be needed to provide a scientific explanation in terms of cell-signaling and confirm the present findings.

• Journal of Life Science
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• v.20 no.1
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• pp.27-32
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• 2010

Ultraviolet-B (UVB) radiation induces the formation of reactive oxygen species (ROS) and depletes stores of cellular antioxidants. Fucoidan, polysaccharides containing L-fucose and sulfate ester groups, are constituents of brown algae. In this study, the protective effects of fucoidan on UVB-induced oxidative stress in cultured human skin fibroblast HS68 cells were assessed. Pretreatment with fucoidan significantly reduced malondialdehyde (MDA) content in a dose-dependent manner. With fucoidan pretreatment at a dose of $100\;{\mu}g/ml$, the level of intracellular glutathione was increased by 21.5%, compared to UVB irradiation alone. Fucoidan significantly reduced UVB-induced ROS generation by 40.1% and 68.4% at 10 and $100\;{\mu}g/ml$, respectively, compared to UVB irradiation alone. The positive staining rates of senescence-associated $\beta$-galactosidase were reduced by 23.1% and 16.4% with 10 and $100\;{\mu}g/ml$ of fucoidan, compared to UVB irradiation alone. Fucoidan may exert a photoprotective effect against UVB radiation-induced oxidative stress.

• YAKHAK HOEJI
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• v.48 no.6
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• pp.374-378
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• 2004

To investigate the whitening activity of Laminaria japonicus, we measured the effect of hot-water extracts on melanin production in B16 melanoma cells. Melanocyte stimulating h ormone (MSH, $1{\mu}M$)-stimulated melanin production in B16 melanoma cells was significantly inhibited by fucoidan and hot-water extracts, but not by alginate. The purified tyrosinase activity was not affected by hot-water extracts, alginate and fucoidan. However, tyrosinase expression was significantly inhibited by fucoidan and hot-water extract in Western blot. These results suggest that inhibitory mechanism of hot-water extracts on melanin production may be due to the inhibition of tyrosinase expression but not to direct inhibition of tyrosinase, such an effect of which may be dependent on fucoidan.

• Fisheries and Aquatic Sciences
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• v.22 no.11
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• pp.24.1-24.7
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• 2019

Sporophylls from sea mustard, Undaria pinnatifida, which are by-products in seaweed production industries, were taken from Hansan Island, Tongyeong, and Gijang, Busan, and investigated for their fucoidan content and corresponding antioxidant activities. The extracted fucoidan yield from sporophylls of sea mustard samples from Tongyeong (TF) and Gijang (GF) were 12.1% and 13.6%, respectively. The antioxidant activities assessment of TF and GF extracts showed relative significant difference between samples, suggesting effect of location on bioactivities of fucoidan samples. GF was 50-68% more effective than TF against DPPH and superoxide radicals samples which may be attributed to the difference in their degree of sulfation and monosaccharide composition. Meanwhile, TF exhibited greater scavenging activity against hydroxyl radicals compared to GF which could be due to protein impurities.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.104-105
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• 2001

Fucoidan은 갈조류 세포 내의 골지체에서 합성되어 세포간물질, 세포벽 구성 물질, 엽상체 표면의 삼출액 둥에 존재하는 산성 다당류의 일종으로 혈액 중에 존재하는 heparin과 그 구조가 비슷하여 혈액 항응고 작용이 있는 것으로 보고(Mori et al., 1982)되어 있으며, 그 외에도 항암작용(Noda, 1990)등 다양한 생리적 기능이 밝혀지고 있다. 또한 fucoidan은 점성이 낮고 용해성이 우수하여 수용성 식이섬유 소재로서의 이용가능성도 매우 높다. (중략)

• Journal of Marine Bioscience and Biotechnology
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• v.2 no.4
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• pp.245-249
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• 2007

High quality of purified alginate and fucoidan is required for the medical uses to prevent the unexpected side effects from the contaminated endotoxin present in the materials. We attempted to establish an efficient and fast mass scale production method for the highly purified poly-G alginate from the sea weeds. In addition, lab scale method was established to obtain the fraction of higher purity from the commercially available fucoidan source (about 85% purity).

• Journal of Microbiology and Biotechnology
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• v.18 no.4
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• pp.616-623
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• 2008

In spite of an increasing interest in fucoidans as biologically active compounds, no convenient commercial sources with fucoidanase activity are yet available. A marine bacterial strain that showed confluent growth on a minimal medium containing fucoidan, prepared from Korean Undaria pinnatifida sporophylls, as the sole carbon source was isolated and identified based on a 16S rDNA sequence analysis as a strain of Sphingomonas paucimobilis, and named Sphingomonas paucimobilis PF-1. The strain depolymerized fucoidan into more than 7 distinct low-molecular-mass fucose-containing oligosaccharides, ranging from 305 to 3,749 Da. The enzyme activity was shown to be associated with the whole cell, suggesting the possibility of a surface display of the enzyme. However, a whole-cell enzyme preparation neither released the monomer L-fucose from the fucoidan nor hydrolyzed the chromogenic substrate p-nitrophenyl-${\alpha}$-L-fucoside, indicating that the enzyme may be an endo-acting fucoidanase rather than an ${\alpha}$-L-fucosidase. Therefore, this would appear to be the first report on fucoidanolytic activity by a Sphingomonas species and also the first report on the enzymatic degradation of the Korean Undaria pinnatifida sporophyll fucoidan. Moreover, this enzyme activity may be very useful for structural analyses of fucose-containing polysaccharides and the production of bioactive fucooligosaccharides.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.3
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• pp.351-358
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• 2007

Carbohydrate-protein interactions are known to be important in gamete interactions. Several evidence indicated that a fucose-containing sulfated polysaccharide fucoidan was potential inhibitor of fertilization in vitro and thus fucose seemed to be part of the recognition signal of gamete interaction in mammals. In recent investigation we found that ${\alpha}$-L-fucosidase activity was present in boar spermatozoa and it was related to sperm binding to and penetration into zona pellucida (ZP) in vitro. The objective of this study was to determine the effects of monosaccharide L-fucose and polysaccharide fucoidan on sperm ${\alpha}$-L-fucosidase activity and relation to sperm-oocyte interaction in pig. Results indicated that the activity of sperm ${\alpha}$-L-fucosidase was largely inhibited (62%) when sperm suspension was treated with monosaccharide L-fucose. It also significantly inhibited the number of sperm binding to ZP (32%) and penetration into zona-intact oocytes (72%), but did not inhibit penetration into zona-free oocytes when fertilization medium contained L-fucose. The chlorotetracycline (CTC) assessment showed that L-fucose did not affect induction of sperm capacitation and acrosome reaction. In contrast, the activity of sperm ${\alpha}$-L-fucosidase was not inhibited when sperm suspension was treated with polysaccharide fucoidan but sperm-ZP binding was greatly inhibited (85%) and completely blocked sperm penetration into zona-intact or zona-free oocytes. The CTC assessment showed that fucoidan increased the F pattern and decreased the AR pattern sperm. These results suggested that the different inhibitory mechanisms were present between monosaccharide L-fucose and polysaccharide fucoidan on sperm-oocyte interaction, the inhibition effect of ${\alpha}$-L-fucose on sperm binding and penetrating into ZP caused sperm ${\alpha}$-L-fucosidase inhibited by ${\alpha}$-L-fucose.