Brown algae are well known as a source of biologically active compounds, especially those having antioxidant activities, such as phlorotannins. In this study we examined the antioxidant activities of crude phlorotannins extracts (CPEs) obtained from Sargassum hemiphyllum (SH) and fractionated according to the molecular weights. When CPEs were administrated at a dose of 30 mg/kg to Kunming mice pre-treated with carbon tetrachloride (CCl4), the levels of oxidative stress indicators in the liver, kidney and brain were significantly reduced in vivo. All the components of various molecular weight fractions of CPEs exhibited greater scavenging capacities in clearing hydroxyl free radical and superoxide anion than the positive controls gallic acid, vitamin C and vitamin E. Particularly, the components greater than 30 kD obtained from ethyl acetate phase showed the highest antioxidant capacities. These results indicated that SH is a potential source for extracting phlorotannins, the algal antioxidant compounds.
Animals ; Antioxidants ; isolation & purification ; pharmacology ; Ascorbic Acid ; pharmacology ; Brain ; drug effects ; metabolism ; pathology ; Carbon Tetrachloride ; antagonists & inhibitors ; toxicity ; Carbon Tetrachloride Poisoning ; drug therapy ; metabolism ; pathology ; Chemical Fractionation ; methods ; Gallic Acid ; pharmacology ; Hydroxyl Radical ; antagonists & inhibitors ; metabolism ; Kidney ; drug effects ; metabolism ; pathology ; Liquid-Liquid Extraction ; methods ; Liver ; drug effects ; metabolism ; pathology ; Male ; Mice ; Mice, Inbred Strains ; Oxidation-Reduction ; Oxidative Stress ; drug effects ; Phaeophyta ; chemistry ; Sargassum ; chemistry ; Superoxides ; antagonists & inhibitors ; metabolism ; Tannins ; isolation & purification ; pharmacology ; Vitamin E ; pharmacology

OBJECTIVETo investigate the chemical constituents of the brown alga Leathesia nana.

METHODCompounds were isolated by normal phase silica gel, Sephadex LH-20 chromatography and reverse phase HPLC techniques. Their structures were elucidated with spectroscopic methods including IR, MS and NMR.

RESULTSix compounds were isolated from ethanolic extract of the brown alga L. nana and their structures were identified as 2,2',3,3'-tetrabromo-4,4',5,5'-tetrahydroxydiphenyl methane, 2,2',3-tribromo-3', 4,4', 5-tetrahydroxy-6'-ethyloxymethyldiphenyl methane, 2,3-dibromo-4,5-dihydroxybenzyl alcohol, 2,3-dibromo-4,5-dihydroxybenzyl methyl ether, 3-bromo-4-hydroxybenzoic acid and 2-bromo-4,5-dihydroxybenzaldehyde.

CONCLUSIONAll these compounds were obtained from this species for the first time.

Benzhydryl Compounds ; chemistry ; isolation & purification ; Ethanol ; Phaeophyta ; chemistry ; Phenols ; chemistry ; isolation & purification

OBJECTIVETo evaluate the antioxidant activities and total phenolic contents of brown seaweeds belonging to Turbinaria spp. [Turbinaria conoides (T. conoides) and Turbinaria ornata (T. ornata) collected from Gulf of Mannar of southeastern coast of India in various in vitro systems.

METHODSThe antioxidant activity was evaluated using different in vitro systems, viz., 1, 1-diphenyl-2-picrylhydrazyl (DPPH), 2, 2'-azino-bis-3 ethylbenzothiozoline-6-sulfonic acid diammonium salt (ABTS), H2O2/HO radical scavenging, Fe(2+) ion chelating ability, and reducing potential. Folin-Ciocalteu method was used to determine the total phenolic content of the extracts, and the results were expressed as mg of gallic acid equivalents (GE)/g of the seaweed extracts. Thiobarbituric acid-reactive substances assay was employed to assess the ability of the seaweed extracts to inhibit lipid oxidation.

RESULTSEthyl acetate (EtOAc) fraction of T. conoides registered significantly higher phenolic content (105.97 mg GE/g) than that of T. ornata (69.63 mg GE/g). Significantly higher antioxidant potential as determined by DPPH (64.14%) radical scavenging activity was registered in EtOAc fraction of T. ornata. A higher ABTS(•+) radical scavenging (IC50 3.16 µg/mL), Fe(2+) chelating (IC50 0.46 mg/mL), H2O2 scavenging (IC50 4.25 mg/mL), lipid peroxidation inhibitory (TBARS, IC50 0.21 mg/mL), and reducing abilities (IC50 52.67 mg/mL) (P<0.05) were realized in EtOAc fraction of T. ornata than other fractions.

CONCLUSIONSThis study indicated the potential use of T. conoides and T. ornata as candidate species to be used as food supplements/functional foods to increase shelf-life of food items for human consumption, and nutraceuticals to deter deleterious free radical-induced life-threatening diseases.

Antioxidants ; analysis ; chemistry ; India ; Phaeophyta ; chemistry ; Phenols ; analysis ; Plant Extracts ; analysis ; chemistry ; Species Specificity

Fucoidan is a sulfated polysaccharide derived from brown algae that has been reported to perform multiple biological activities, including immunostimulation. In this study, we investigated whether fucoidan has beneficial effects on endotoxemia induced by LPS, a septic model in mice. The focus of this study was on survival rates and spleen function of the mice upon treatment. We found that fucoidan had prophylactic effects on the survival rate of mice with endotoxemia. Flow cytometric analysis using antibodies for subset-specific markers revealed that fucoidan profoundly reversed the depleted population of dendritic cells in mice with endotoxemia. According to Western blot analysis, the spleen cells of LPS/fucoidan-treated mice showed a higher expression of anti-apoptotic molecules compared to those of LPS-treated mice. Also, fucoidan-treated spleen cells were more responsive to mitogens. Taken together, these results demonstrate that fucoidan pre-treatment has beneficial effects on the survival rate and function of the spleen in mice with endotoxemia. This study may broaden the use of fucoidan in clinical fields, especially endotoxemia.
Animals ; Antibodies ; Blotting, Western ; Dendritic Cells ; Endotoxemia ; Immunization ; Mice ; Mitogens ; Phaeophyta ; Polysaccharides ; Spleen ; Survival Rate

Fucoidan, a fucose-rich sulfated polysaccharide derived from brown seaweed in the class Phaeophyceae, has been widely studied for its possible health benefits. However, the potential of fucoidan as a possible treatment for hyperpigmentation is not fully understood. This study investigated the effects of fucoidan on melanogenesis and related signaling pathways using Mel-Ab cells. Fucoidan significantly decreased melanin content. While fucoidan treatment decreased tyrosinase activity, it did not do so directly. Western blot analysis indicated that fucoidan downregulated microphthalmia-associated transcription factor and reduced tyrosinase protein expression. Further investigation showed that fucoidan activated the extracellular signal-regulated kinase (ERK) pathway, suggesting a possible mechanism for the inhibition of melanin synthesis. Treatment with PD98059, a specific ERK inhibitor, resulted in the recovery of melanin production. Taken together, these findings suggest that fucoidan inhibits melanogenesis via ERK phosphorylation.
Blotting, Western ; Hyperpigmentation ; Insurance Benefits ; Melanins ; Microphthalmia-Associated Transcription Factor ; Monophenol Monooxygenase ; Phaeophyta ; Phosphorylation ; Phosphotransferases ; Seaweed

BACKGROUND/OBJECTIVES: Seaweeds have been reported to have various health beneficial effects. In this study, we investigated the potential anti-obesity and anti-inflammatory effects of four types of domestic brown seaweeds in a high-fat diet-induced obese mouse model and bone marrow-derived macrophages (BMDM). MATERIALS/METHODS: Male C57BL/6N mice were fed low-fat diet (LFD), high-fat diet (HFD) or HFD containing Undaria Pinnatifida, HFD containing Laminaria Japonica (LJ), HFD containing Sargassum Fulvellum, or HFD containing Hizikia Fusiforme (HF) for 16 weeks. RESULTS: Brown seaweed supplementation did not affect long-term HFD-associated changes in body weight or adiposity, although mice fed HFD + LJ or HFD + HF gained slightly less body weight compared with those fed HFD at the beginning of feeding. Despite being obese, mice fed HFD + LJ appeared to show improved insulin sensitivity compared to mice fed HFD. Consistently, we observed significantly reduced blood glucose concentrations in mice fed HFD + LJ compared with those of mice fed HFD. Although no significant differences in adipocyte size were detected among the HFD-fed groups, consumption of seaweeds decreased formation of HFD-induced crown-like structures in gonadal adipose tissue as well as plasma inflammatory cytokines. BMDM from mice fed HFDs with seaweeds showed differential regulation of pro-inflammatory cytokines such as IL-1beta and IL-6 compared with BMDM from mice fed HFD by LPS stimulation. CONCLUSION: Although seaweed consumption did not prevent long-term HFD-induced obesity in C57BL/6N mice, it reduced insulin resistance (IR) and circulation of pro-inflammatory cytokines. Therefore, seaweeds may ameliorate systemic inflammation and IR in obesity partially due to inhibition of inflammatory signaling in adipose tissue cells as well as bone marrow-derived immune cells.
Adipocytes ; Adipose Tissue ; Adiposity ; Animals ; Blood Glucose ; Body Weight ; Cytokines ; Diet, Fat-Restricted ; Diet, High-Fat ; Gonads ; Humans ; Inflammation ; Insulin Resistance ; Interleukin-6 ; Laminaria ; Macrophages ; Male ; Mice ; Mice, Obese* ; Obesity ; Plasma ; Sargassum ; Seaweed ; Undaria

In this study, antioxidant and free radical scavenging activities of the natural antioxidative compound, pyrogallol-phloroglucinol-6,6'-bieckol (PPB) isolated from brown algae, Ecklonia cava was assessed in vitro by measuring the radical scavenging activities (DPPH, alkyl, hydroxyl, and superoxide) using electron spin resonance (ESR) spectrometry, intracellular reactive oxygen species (ROS) scavenging activity, and DNA damage assay. According to the results of these experiments, the scavenging activity PPB against difference radicals was in the following order: DPPH, alkyl, hydroxyl, and superoxide radicals (IC50; 0.90, 2.54, 62.93 and 109.05 microM). The antioxidant activities of PPB were higher than that of the commercial antioxidant, ascorbic acid. Furthermore, PPB effectively inhibited DNA damage induced by H2O2. These results suggest that the natural antioxidative compound, PPB, can be used by the natural food industry.
Ascorbic Acid ; DNA Damage ; Electron Spin Resonance Spectroscopy ; Food Industry ; Phaeophyta ; Reactive Oxygen Species ; Spectrum Analysis ; Superoxides

When exposed to gamma-rays, hair follicular cells immediately go through apoptosis, which hampers their rapid differentiation essential for the regeneration of hair. Phloroglucinol (PG) is a phenolic compound of Ecklonia cava, brown algae abundant in Jeju island, Korea. Containing plentiful polyphenols, PG is known for its instructive effects by inhibiting apoptosis, scavenging oxygen radicals, and protecting cells against oxidative stress. In this study, we demonstrate that PG rescues radiosensitive hair follicular cells from gamma radiation-induced apoptosis and DNA damage. To identify protective capacity of PG on hair follicles, we irradiated with 8.5 Gy (1.5 Gy/min) of gamma-rays to the whole body of C57BL/6 mice at day 6 after depilation with or without PG. In mice exposed to radiation, the expression of proapoptotic molecule p53 was downregulated in the skin of PG treated group. On immunohistochemical observation of the skin, PG inhibited the immunoreactivity of p53 and cleaved caspase-3. PG treatment protected hair follicular cells from cell death due to gamma-radiation. Our results suggest that PG presents radioprotective effects by inhibiting apoptosis of radiosensitive hair follicular cells and can protect hair follicular cells from gamma-ray induced damage.
Animals ; Apoptosis ; Caspase 3 ; Cell Death ; DNA Damage ; Hair Follicle* ; Hair Removal ; Hair* ; Korea ; Mice ; Oxidative Stress* ; Phaeophyta ; Phenol ; Phloroglucinol* ; Polyphenols ; Reactive Oxygen Species ; Regeneration ; Skin

Fucoidan, a sulfated polysaccharide is found in several types of edible brown algae. It has shown numerous biological activities; however, the molecular mechanisms on the activity against atopic dermatitis have not been reported yet. We now examined the effects of fucoidan on chemokine production co-induced by TNF-alpha/IFN-gamma, and the possible mechanisms underlying these biological effects. Our data showed that fucoidan inhibited the TNF-alpha/IFN-gamma-induced production of thymus and activation-regulated chemokine (TARC) and macrophagederived chemokine (MDC) mRNA in human keratinocytes HaCaT cells. Also, fucoidan suppressed phosphorylation of nuclear factor kappa B (NF-kappaB) and activation of signal transducer and activator of transcription (STAT)1 in a dose-dependent manner. In addition, fucoidan significantly inhibited activation of extracellular-signal-regulated kinases (ERK) phosphorylation. These data indicate that fucoidan shows anti-inflammatory effects by suppressing the expression of TNF-alpha/IFN-gamma-induced chemokines by blocking NF-kappaB, STAT1, and ERK1/2 activation, suggestive of as used as a therapeutic application in inflammatory skin diseases, such as atopic dermatitis.
Chemokine CCL17 ; Chemokines ; Dermatitis, Atopic ; Humans* ; Keratinocytes* ; NF-kappa B* ; Phaeophyta ; Phosphorylation ; Phosphotransferases ; RNA, Messenger ; Skin Diseases ; STAT1 Transcription Factor ; Transducers

Marine can be considered as a rather unexplored source of biological material. Production of algal oligosaccharides by using valuable enzymes from marine origin has become an important way to utilize marine resources. As one of algal tool enzymes, the use of alginate lyases has been focused mainly on development and application of alginate oligosaccharides with bioactive function in recent years. In this paper, we reviewed the research of alginate lyases over the past decade in several aspects, including their origin, diversity, substrate specification, mode of action, structure and catalysis mechanism, assay of enzyme activity, enzyme characterization, as well as our own experience on this subject. At the end of the review, the application prospects of alginate lyases are presented.
Alginates ; metabolism ; Glucuronic Acid ; metabolism ; Hexuronic Acids ; metabolism ; Marine Biology ; methods ; Oligosaccharides ; metabolism ; Phaeophyta ; enzymology ; Polysaccharide-Lyases ; classification ; isolation & purification ; metabolism ; Substrate Specificity