Characterization of flavor substances in cooking and seasoned cooking brown seaweeds by GC-IMS and E-nose

The flavor of algae was one of the key factors for consumer acceptance. The objective of this study was to investigate the characteristic volatile compounds in cooking and seasoned cooking edible brown seaweeds (Undaria pinnatifida and Laminaria japonica). The gas chromatography-ion mobility spectrometry (GC-IMS) and electronic nose (E-nose) analysis showed that baking resulted in significant difference in flavor of brown seaweeds. However, the overall effect of cooking was not as significant as that of the seasoning solution treatment. Additionally, brown seaweeds treated with the seasoning solution were more acceptable. Undaria pinnatifida was found to contain 72 volatile flavor compounds, while Laminaria japonica had a total of 70. This study proved the applicability of GC-IMS combined with E-nose technology to detect the changes of volatile components of brown seaweeds after processing, providing beneficial knowledge and basic theory for the deep processing of brown seaweeds.

Effect of Seaweed-Derived Fucoidans from Undaria pinnatifida and Fucus vesiculosus on Coagulant, Proteolytic, and Phospholipase A2 Activities of Snake Bothrops jararaca, B. jararacussu, and B. neuwiedi Venom

BACKGROUND

Snakebite envenomation (SBE) causes diverse toxic effects in humans, including disability and death. Current antivenom therapies effectively prevent death but fail to block local tissue damage, leading to an increase in the severity of envenomation; thus, seeking alternative treatments is crucial.

METHODS

This study analyzed the potential of two fucoidan sulfated polysaccharides extracted from brown seaweeds Fucus vesiculosus (FVF) and Undaria pinnatifida (UPF) against the fibrinogen or plasma coagulation, proteolytic, and phospholipase A2 (PLA2) activities of Bothrops jararaca, B. jararacussu, and B. neuwiedi venom. The toxicity of FVF and UPF was assessed by the hemocompatibility test.

RESULTS

FVF and UPF did not lyse human red blood cells. FVF and UPF inhibited the proteolytic activity of Bothrops jararaca, B. jararacussu, and B. neuwiedi venom by approximately 25%, 50%, and 75%, respectively, while all venoms led to a 20% inhibition of PLA2 activity. UPF and FVF delayed plasma coagulation caused by the venoms of B. jararaca and B. neuwiedi but did not affect the activity of B. jararacussu venom. FVF and UPF blocked the coagulation of fibrinogen induced by all these Bothropic venoms.

CONCLUSION

FVF and UPF may be of importance as adjuvants for SBE caused by species of Bothrops, which are the most medically relevant snakebite incidents in South America, especially Brazil.

Effect of Fucoidan on Structure and Bioactivity of Chinese Steamed Bread

Fucoidan refers to a group of sulphated polysaccharides obtained from brown seaweed, with numerous biological activities. In this study, fucoidan was fortified into Chinese steamed bread (CSB) at different concentrations (0, 1%, 3% and 5%) and the effect of fucoidan on the dough properties, structure properties and bioactivity were investigated. The results showed that fucoidan could change the viscosity of unfermented dough, and a high concentration of fucoidan could remove the free radicals produced by the SH-SS exchange reaction (GS-) in the dough, which significantly reduced the content of disulfide bond and reduced the expanded volume of fermented dough (p < 0.05). In addition, fucoidan forms a physical barrier on the surface of starch particles and hinders the reaction between protein-to-protein; therefore, fucoidan increased the hardness, gumminess and chewiness in CSB, and reduced the specific volume in CSB. Furthermore, the fucoidan-fortified CSB samples were found to have both the ability to significantly reduce the predicted glycemic index (pGI) (p < 0.05) and improve antioxidant activity (p < 0.05). Collectively, these findings could provide a theoretical basis for the applications of fucoidan as a functional component in fermented foods.

Temporal and Within-Sporophyte Variations in Triphenyltin Chloride (TPTCL) and Its Degradation Products in Cultivated Undaria pinnatifida

Undaria pinnatifida can effectively deal with organotin pollution through its excellent accumulation and degradation capabilities found under laboratory conditions. However, nothing is known regarding its accumulation, degradation performance, and related impact factors in the wild farming area. In this study, we monitored triphenyltin chloride (TPTCL) contents and degradation products in different algal parts (blades, stipes, sporophylls, and holdfasts) of cultivated U. pinnatifida from December 2018 to May 2019. Our results showed that sporophytes had an accumulation and degradation capacity for TPTCL. The TPTCL contents and degradation products varied with the algal growth stages and algal parts. TPTCL accumulated in the blades at the growth stage and the blades, stipes, sporophylls, and holdfasts at the mature stage. The TPTCL content among algal parts was blades (74.92 ± 2.52 μg kg-1) > holdfasts (62.59 ± 1.42 μg kg-1) > sporophylls (47.24 ± 1.41 μg kg-1) > stipes (35.53 ± 0.55 μg kg-1). The primary degradation product DPTCL accumulated only in the blades at any stage, with a concentration of 69.30 ± 3.89 μg kg-1. The secondary degradation product MPTCL accumulated in the blades at the growth stage and in the blades, stipe, and sporophyll at the mature stage. The MPTCL content among algal parts was blades (52.80 ± 3.48 μg kg-1) > sporophylls (31.08 ± 1.53 μg kg-1) > stipes (20.44 ± 0.85 μg kg-1). The accumulation pattern of TPTCL and its degradation products seems closely related to nutrient allocation in U. pinnatifida. These results provide the basis for applying cultivated U. pinnatifida in the bioremediation of organotin pollution and the food safety evaluation of edible algae.

Undaria pinnatifida ameliorates nasal inflammation by inhibiting eosinophil and mast cell activation and modulating the NF-κB/MAPKs signaling pathway

BACKGROUND

Allergic rhinitis (AR) is the most prevalent form of atopic disease. Undaria pinnatifida has potent antioxidative, antidiabetic, and anti-inflammatory properties.

AIMS

We investigated the immunomodulatory effect of Undaria pinnatifida extract (UPE) on allergic inflammation in an AR mouse model.

MATERIALS & METHODS

Mice were sensitized and intranasally challenged with ovalbumin (OVA), and the Th1/Th2 and Th17/Treg-related cytokines and histopathology were exanimated after UPE treatments. Enzyme-linked immunosorbent assay was performed using serum samples and NALF to detect OVA-specific immunoglobulins and inflammatory cytokines. Mitogen-activated protein kinases (MAPKs) were measured by western blotting analysis, and an in vitro study measured mast cell activation induced by compound 48/80.

RESULTS

After UPE treatment, nasal and lung allergy symptoms, nasal mucosal swelling, and goblet cell hyperplasia were ameliorated. Oral UPE regulated the balance of Th1/Th2 and Th17/Treg cell differentiation in AR mice in a dose-dependent manner. In addition, UPE attenuated the migration of eosinophils and mast cells to the nasal mucosa by suppressing nuclear factor kappa B (NF-κB)/MAPKs. The levels of anti-OVA IgE and IgG1 were also decreased.

DISCUSSION

UPE inhibited inflammation by regulating the NF-κB/MAPKs signaling pathway and supressing the activation of critical immune cells such as eosinophils and mast cells.

CONCLUSION

UPE may have therapeutic potential for AR.

Long-term response of the microbial community to the degradation of DOC released from Undaria pinnatifida

With the aim to study the mechanism underlying the macroalgal carbon sequestration driven by microbes, we investigated the microbial community using metagenomics methods and its long-term degradation of dissolved organic carbon (DOC) derived from Undaria pinnatifida. It was observed that after removing U. pinnatifida, the concentration of the DOC decreased significantly (p < 0.05) within 4 days. Over a period of 120 days of degradation, the concentration of remaining DOC (26%) remained stable. The succession of microbial community corresponded to the three stages of DOC concentration variation. Moreover, the structure of microbes community and its metabolic function exhibited evident patterns of succession. The concentration of DOC was correlated negatively with the abundances of Planctomycetaceae (p < 0.01), and was correlated positively with the abundances of Roseobacteraceae and Rhodobacteraceae (p < 0.01). In addition, the metabolic pathways related to "Glycolysis/Gluconeogenesis", "Alanine, aspartate, and glutamate metabolism", "Citrate cycle (TCA cycle)" and "Tryptophan metabolism" was significantly correlated with the variations in DOC concentration (p < 0.05). These findings indicate that the variation in the DOC concentration was closely linked to the succession of Planctomycetaceae, Roseobacteraceae, Rhodobacteraceae, and the degradation of DOC derived from U. pinnatifida appeared to be influenced by metabolic functions.

Synbiotic Fermentation of Undaria pinnatifida and Lactobacillus brevis to Produce Prebiotics and Probiotics

It has been optimized thermal acid hydrolytic pretreatment and enzymatic saccharification (Es) in flask culture of Undaria pinnatifida seaweed, which is a prebiotic. The optimal hydrolytic conditions were a slurry content of 8% (w/v), 180 mM H2SO4, and 121°C for 30 min. Es using Celluclast 1.5 L at 8 U/mL produced 2.7 g/L glucose with an efficiency of 96.2%. The concentration of fucose (a prebiotic) was 0.48 g/L after pretreatment and saccharification. The fucose concentration decreased slightly during fermentation. Monosodium glutamate (MSG) (3%, w/v) and pyridoxal 5'-phosphate (PLP) (30 μM) were added to enhance gamma-aminobutyric acid (GABA) production. To further improve the consumption of mixed monosaccharides, adaptation of Lactobacillus brevis KCL010 to high concentrations of mannitol improved the synbiotic fermentation efficiency of U. pinnatifida hydrolysates.

Development of a microplate-based novel toxicity bioassay using Chlorophyta and Phaeophyceae macroalgae

Macroalgae are one of the main producers in marine environments. However, only a few toxicity test methods have been established that use reference strains of macroalgae to evaluate the effects of chemicals on the growth and reproduction of macroalgae to monitor water quality. We selected reference strains of Chlorophyta, Ulva aragoënsis; Phaeophyceae, Ectocarpus siliculosus; and wakame, Undaria pinnatifida, as test species to establish a microplate-based method to investigate the toxicity of potassium dichromate, 3,5-dichlorophenol, and two common herbicides (diuron and simazine). We determined the growth of the three macroalgae in their early life stages and during the sporangia formation stage in E. siliculosus under laboratory conditions. We observed that the growth and sporangia formation in these algae were impaired in a dose-dependent manner. Additionally, we investigated the sensitivity of these macroalgae by comparing the toxicity values of toxicants used in this study with those obtained from a database. Compared to other microalgae and plant species, macroalgae showed a relatively high sensitivity to organic compounds, including herbicides. Growth tests using U. aragoënsis and E. siliculosus produced reliable results at 0-32 and 25-32 practical salinity units (PSU), respectively. The tests established in this study could test the toxicity of chemical substances in macroalgae and are thus expected to contribute to a better understanding of the environmental risks of chemical substances on aquatic biota. The tests could be applied to all effluent toxicity tests used for the management of seawater and brackish water quality.

Kinetic Extraction of Fucoxanthin from Undaria pinnatifida Using Ethanol as a Solvent

Fucoxanthin (Fx) has been proven to exert numerous biological properties, which makes it an interesting molecule with diverse industrial applications. In this study, the kinetic behavior of Fx was studied to optimize three variables: time (t-3 min to 7 days), temperature (T-5 to 85 °C), and concentration of ethanol in water (S-50 to 100%, v/v), in order to obtain the best Fx yield from Undaria pinnatifida using conventional heat extraction. The Fx content (Y1) was found through HPLC-DAD and expressed in µg Fx/g of algae sample dry weight (AS dw). Furthermore, extraction yield (Y2) was also found through dry weight analysis and was expressed in mg extract (E)/g AS dw. The purity of the extracts (Y3) was found and expressed in mg Fx/g E dw. The optimal conditions selected for Y1 were T = 45 °C, S = 70%, and t = 66 min, obtaining ~5.24 mg Fx/g AS; for Y2 were T = 65 °C, S = 60%, and t = ~10 min, obtaining ~450 mg E/g AS; and for Y3 were T = 45 °C, S = 70%, and t = 45 min, obtaining ~12.3 mg Fx/g E. In addition, for the selected optimums, a full screening of pigments was performed by HPLC-DAD, while phenolics and flavonoids were quantified by spectrophotometric techniques and several biological properties were evaluated (namely, antioxidant, antimicrobial, and cholinesterase inhibitory activity). These results could be of interest for future applications in the food, cosmetic, or pharmaceutical industries, as they show the Fx kinetic behavior and could help reduce costs associated with energy and solvent consumption while maximizing the extraction yields.

Valorisation of the Invasive Macroalgae Undaria pinnatifida (Harvey) Suringar for the Green Synthesis of Gold and Silver Nanoparticles with Antimicrobial and Antioxidant Potential

Bacterial and fungal infections are a challenging global problem due to the reported increasing resistance of pathogenic microorganisms to conventional antimicrobials. Nanomaterials are a promising strategy to fight infections caused by multidrug-resistant microbes. In this work, gold (Au@UP) and silver (Ag@UP) nanoparticles were produced for the first time by green synthesis using an aqueous extract of the invasive macroalgae Undaria pinnatifida (UP). The nanoparticles were characterized by a wide range of physicochemical techniques. Au@UP and Ag@UP demonstrated to be spherical and crystalline with an average size of 6.8 ± 1.0 nm and 14.1 ± 2.8 nm, respectively. Carbohydrates and proteins of the UP extract may participate in the synthesis and capping of the nanoparticles. The UP extract, Ag@UP, and Au@UP were assessed for their antimicrobial activity against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, and Candida auris. Ag@UP showed the highest antimicrobial activity with very low MIC and MBC values for all the tested bacteria, and Au@UP demonstrated to be very effective against biofilm-producing bacteria. The antifungal properties of both Ag@UP and Au@UP were remarkable, inhibiting hyphae formation. This study points towards a very promising biomedical exploitation of this invasive brown algae.

Gametophyte phase of commercial kelps, the potential food supplements for essential fatty acids and n-3 polyunsaturated fatty acids

For heteromorphic algae with alternating generations, the thallus and gametophyte phases are different morphologies in free-living life history. The thalli are popular used as traditional vegetables and herbal drugs, whereas the gametophyte phases are little involved. To better understand the functional lipids in the gametophyte phase of three commercial kelps, Saccharina japonica, Undaria pinnatifida, and Costaria costata, the contents of total lipids (TLs), fatty acid (FA) profiles, and transcriptomic analysis were performed. For the studied kelps, the TL contents in gametophyte phase were always almost twice more than those in the thallus, and the kelp species, their life stage, and the gender were critical factors affecting lipid accumulation. The gametophyte phases of U. pinnatifida and C. costata were rich in essential FA C18:2 n - 6 and C18:3 n - 3. The S. japonica gametophyte phase contained abundant C20:5 n - 3 and C18:4 n - 3, possessed an ideal ratio of n - 6/n - 3 polyunsaturated fatty acid below 1.0, and was supported by the transcriptome data which showed that the key sjD12/15 (n - 3) gene of gametophyte partially upregulated than sporophyte. The results suggested that S. japonica gametophyte phase was the worthiest of further development and utilization as a functional food. PRACTICAL APPLICATION: It is the first report on the fatty acid characteristics of three gametophyte phases of Saccharina japonica, Undaria pinnatifida, and Costaria costata and find that the S. japonica was worthy of further development and utilization as a functional food owing to its satisfactory fatty acid composition.

Emerging Technologies to Extract Fucoxanthin from Undaria pinnatifida: Microwave vs. Ultrasound Assisted Extractions

Macroalgae are an extensive resource for the obtention of bioactive compounds, mainly phenolic compounds, phlorotannins, and pigments. Fucoxanthin (Fx) is the most abundant pigment present in brown algae and has shown several useful bioactivities that can be used to fortify products in the food and cosmetic industries. Nevertheless, to date, there is still insufficient literature reporting on the extraction yield of Fx from U. pinnatifida species from green technologies. In this regard, the present study aims to optimize the extraction conditions to obtain the highest Fx yield from U. pinnatifida through emerging techniques, namely microwave-assisted extraction (MAE) and ultrasound-assisted extraction (UAE). These methods will be compared with the conventional methodologies of heat-assisted extraction (HAE) and Soxhlet-assisted extraction (SAE). According to our results, even though the extraction yield could be slightly higher when using MAE than UAE, the Fx concentration obtained from the alga was double when using UAE. Thus, the Fx ratio in the final extract reached values of 124.39 mg Fx/g E. However, the optimal conditions should also be considered since UAE needed 30 min to perform the extraction, whereas MAE was able to obtain 58.83 mg Fx/g E in only 3 min and 2 bar, meaning less energy expenditure and minimum cost function. To our knowledge, this study obtains the highest concentrations of Fx ever reported (58.83 mg Fx/g E for MAE and 124.39 mg Fx/g E for UAE), with low energy consumption and short times (3.00 min for MAE and 35.16 min for UAE). Any of these results could be selected for further experiments and proposed for industrial scaling-up.

One-Step Preparative Separation of Fucoxanthin from Three Edible Brown Algae by Elution-Extrusion Countercurrent Chromatography

A method for batch preparation of fucoxanthin from brown algae was established, which possessed the advantages of high yield and high purity. The ultrasonic-assisted extraction method was used to obtain a crude extract from Sargassum fusiforme as the separation sample. Then the crude extract was separated by elution-extrusion countercurrent chromatography. The optimum preparation conditions of fucoxanthin were determined as follows: n-hexane-ethanol-water (20:9:11, v:v:v) as a two-phase solvent system, the mobile phase flow rate was 5 mL min-1, the revolution speed was 800 r min-1, the loading capacity was 60 mg 10 mL-1 and the temperature was 25 °C. By this method, 12.8 mg fucoxanthin with a purity of 94.72% was obtained from the crude extract of Sargassum fusiforme. In addition, when the loading capacity was 50 mg 10 mL-1, the purity of fucoxanthin reached 96.01%. Two types of by-products, chlorophyll and pheophytin, could also be obtained during the process of separation. This optimal method was further applied to separate fucoxanthin from Laminaria japonica and Undaria pinnatifida, and 6.0 mg and 9.7 mg fucoxanthin with a purity of 96.24% and 92.62% were acquired, respectively. Therefore, it was demonstrated that the preparation method of fucoxanthin established in this study had an applicability to brown algae, which improved the utilization value of raw materials.

In Vitro and In Vivo Dendritic Cell Immune Stimulation Effect of Low Molecular Weight Fucoidan from New Zealand Undaria pinnatifida

Low molecular weight fucoidan (LMWF) has been reported to have immunomodulation effects through the increase of the activation and function of macrophages. In this study, the regulating effect of LMWF from Undaria pinnatifida grown in New Zealand on dendritic cells (DCs) was investigated. We discovered that LMWF could stimulate DCs' maturation and migration, as well as CD4+ and CD8+ T cells' proliferation in vitro. We proved that this immune promoting activity is activated through TLR4 and its downstream MAPK and NF-κB signaling pathways. Further in vivo (mouse model) investigation showed that LMWF has a strong immunological boosting effect, such as facilitating the proliferation of immune cells and increasing the index of immune organs. These findings suggest that LMWF has a positive immunomodulatory effect and is a promising candidate to supplement cancer immunotherapy.

Anti-Inflammatory Activity of Fucoidan Extracts In Vitro

Fucoidans are sulfated, complex, fucose-rich polymers found in brown seaweeds. Fucoidans have been shown to have multiple bioactivities, including anti-inflammatory effects, and are known to inhibit inflammatory processes via a number of pathways such as selectin blockade and enzyme inhibition, and have demonstrated inhibition of inflammatory pathologies in vivo. In this current investigation, fucoidan extracts from Undaria pinnatifida, Fucus vesiculosus, Macrocystis pyrifera, Ascophyllum nodosum, and Laminaria japonica were assessed for modulation of pro-inflammatory cytokine production (TNF-α, IL-1β, and IL-6) by human peripheral blood mononuclear cells (PBMCs) and in a human macrophage line (THP-1). Fucoidan extracts exhibited no signs of cytotoxicity in THP-1 cells after incubation of 48 h. Additionally, all fucoidan extracts reduced cytokine production in LPS stimulated PBMCs and human THP-1 cells in a dose-dependent fashion. Notably, the 5-30 kDa subfraction from Macrocystis pyrifera was a highly effective inhibitor at lower concentrations. Fucoidan extracts from all species had significant anti-inflammatory effects, but the lowest molecular weight subfractions had maximal effects at low concentrations. These observations on various fucoidan extracts offer insight into strategies that improve their efficacy against inflammation-related pathology. Further studies should be conducted to elucidate the mechanism of action of these extracts.

Influence of Domestic Cooking on Quality, Nutrients and Bioactive Substances of Undaria pinnatifida

Undaria pinnatifida (UP) is a brown algae commonly consumed as food in Asian countries. The purpose of this study was to compare the effects of different domestic cooking methods (i.e., air frying (AF), microwaving, and high temperature and pressure (HTP) cooking) on the nutritional and bioactive substances in UP, as well as on UP color and texture, in order to identify methods to retain beneficial components better. In this study, microwave treatment resulted in better retention of color, polysaccharide (4.17 ± 0.07 mg glucose equivalents (GE)/g dry weight (dw) ), total phenol content (TPC) (1.50 ± 0.0062 mg gallic acid equivalents (GAE)/g dw) as well as chlorophyll a (18.18 ± 0.41 mg/g fresh weight (fw) ) and fucoxanthin (281.78 ± 17.06 μg/g dw). HTP treatment increased the TPC of UP (1.69 ± 0.0075 mg GAE/g dw), and AF treatment resulted in a lower loss of total amino acids (2.14 ± 0.15%). Overall, microwave cooking appeared to be the best among the three in producing cooked UP with high quality. This study provided a useful guideline in selection of cooking for UP which could retain more health-beneficial substances and yield products with better eating qualities to improve human diet.

Proteins extracted from seaweed Undaria pinnatifida and their potential uses as foods and nutraceuticals

Isolation and utilization of proteins from seaweeds have been a novel trend in the world at present due to the increasing demand for healthy non-animal proteins. The attention of scientific community has been paid on the protein derived from seaweed Undaria pinnatifida due to their high nutritional quality and bioactivity. This article aims to provide an integrated overview on methods of extraction, isolation and purification of U. pinnatifida-derived proteins and composition, nutritional value and potential nutraceutical and food applications with an interest to stimulate further research to optimize the utilization. Potential food applications of U. pinnatifida derived proteins are nutritional components in human diet, food ingredients and additives, alternative meat and meat analogues and animal and fish feed. Excellent antioxidant, antihypertension, anticoagulant, anti-diabetes, antimicrobial and anti-cancer activities possessed by proteins of U. pinnatifida enable the use of these proteins in various nutraceutical applications. A number of studies have been carried out on antioxidant and antihypertensive activities of U. pinnatifida proteins, whereas other bioactivites are yet to be further studied. Hence, more research works are crucial to be done in order to facilitate and promote the emerging novel foods and nutraceuticals, using proteins from seaweed U. pinnatifida.

Undaria pinnatifida fucoidan nanoparticles loaded with quinacrine attenuate growth and metastasis of pancreatic cancer

Pancreatic cancer is a devastating gastrointestinal tumor with limited Chemotherapeutic options. Treatment is restricted by its poor vascularity and dense surrounding stroma. Quinacrine is a repositioned drug with an anticancer activity but suffers a limited ability to reach tumor cells. This could be enhanced using nanotechnology by the preparation of quinacrine-loaded Undaria pinnatifida fucoidan nanoparticles. The system exploited fucoidan as both a delivery system of natural origin and active targeting ligand. Lactoferrin was added as a second active targeting ligand. Single and dual-targeted particles prepared through nanoprecipitation and ionic interaction respectively were appraised. Both particles showed a size lower than 200 nm, entrapment efficiency of 80% and a pH-dependent release of the drug in the acidic environment of the tumor. The anticancer activity of quinacrine was enhanced by 5.7 folds in dual targeted particles compared to drug solution with a higher ability to inhibit migration and invasion of cancer. In vivo, these particles showed a 68% reduction in tumor volume compared to only 20% for drug solution. In addition, they showed a higher animals' survival rate with no hepatotoxicity. Hence, these particles could be an effective option for the eradication of pancreatic cancer cells.

Comparison of edible brown algae extracts for the inhibition of intestinal carbohydrate digestive enzymes involved in glucose release from the diet

Type II diabetes is considered the most common metabolic disorder in the developed world and currently affects about one in ten globally. A therapeutic target for the management of type II diabetes is the inhibition of α- glucosidase, an essential enzyme located at the brush border of the small intestinal epithelium. The inhibition of α-glucosidase results in reduced digestion of carbohydrates and a decrease in postprandial blood glucose. Although pharmaceutical synthetic inhibitors are available, these are usually associated with significant gastrointestinal side effects. In the present study, the impact of inhibitors derived from edible brown algae is being investigated and compared for their effect on glycaemic control. Carbohydrate- and polyphenolic-enriched extracts derived from Ascophyllum nodosum, Fucus vesiculosus and Undaria pinnatifida were characterised and screened for their inhibitory effects on maltase and sucrase enzymes. Furthermore, enzyme kinetics and the mechanism of inhibition of maltase and sucrase were determined using linear and nonlinear regression methods. All tested extracts showed a dose-dependent inhibitory effect of α-glucosidase with IC50 values ranging from 0⋅26 to 0⋅47 mg/ml for maltase; however, the only extract that was able to inhibit sucrase activity was A. nodosum, with an IC50 value of 0⋅83 mg/ml. The present study demonstrates the mechanisms in which different brown seaweed extracts with varying composition and molecular weight distribution differentially inhibit α-glucosidase activities. The data highlight that all brown seaweed extracts are not equal in the inhibition of carbohydrate digestive enzymes involved in postprandial glycaemia.

Undaria pinnatifida improves obesity-related outcomes in association with gut microbiota and metabolomics modulation in high-fat diet-fed mice

Dietary fiber has beneficial effects on obesity-related diseases and gut microbiota, contributing a key role in the interaction between dietary metabolism and host metabolism. Our objective was to investigate the cause of the improvement in multiple types of physiological states with seaweed Undaria pinnatifida treatment on high-fat diet-fed mice and to evaluate whether its consequent anti-adiposity and anti-hyperlipidemic effects are associated with gut microbiota and its metabolomics regulation. U. pinnatifida administration in our experiment was shown to significantly decrease high-fat diet-induced body weight gain, as well as epididymal and abdominal adiposity. U. pinnatifida intake also significantly reduced liver weight and serum triacylglycerol accumulation. We also found that improving effects of U. pinnatifida on high-fat diet-induced metabolic dysfunctions were associated with significant increase in specific bacteria, such as Bacteroides acidifaciens and Bacteroides ovatus, as well as metabolites, including short-chain fatty acids and tricarboxylic acid cycle intermediates. Our result provides a cheap dietary strategy to host metabolism improvement and obesity management. KEY POINTS: • U. pinnatifida improved adipose accumulation and lipid metabolism. • B. acidifaciens and B. ovatus contributed to the beneficial effects of U. pinnatifida. • SCFAs and TCA cycle intermediates were critical to the metabolic outcomes. • Our study provides a cheap dietary strategy for obesity management.

Brown Seaweeds for the Management of Metabolic Syndrome and Associated Diseases

Metabolic syndrome is characterized by the coexistence of different metabolic disorders which increase the risk of developing type 2 diabetes mellitus and cardiovascular diseases. Therefore, metabolic syndrome leads to a reduction in patients' quality of life as well as to an increase in morbidity and mortality. In the last few decades, it has been demonstrated that seaweeds exert multiple beneficial effects by virtue of their micro- and macronutrient content, which could help in the management of cardiovascular and metabolic diseases. This review aims to provide an updated overview on the potential of brown seaweeds for the prevention and management of metabolic syndrome and its associated diseases, based on the most recent evidence obtained from in vitro and in vivo preclinical and clinical studies. Owing to their great potential for health benefits, brown seaweeds are successfully used in some nutraceuticals and functional foods for treating metabolic syndrome comorbidities. However, some issues still need to be tackled and deepened to improve the knowledge of their ADME/Tox profile in humans, in particular by finding validated indexes of their absorption and obtaining reliable information on their efficacy and long-term safety.

Sexual Difference in the Optimum Environmental Conditions for Growth and Maturation of the Brown Alga Undaria pinnatifida in the Gametophyte Stage

Undaria pinnatifida is an annual brown kelp growing naturally in coastal areas as a major primary producer in temperate regions and is cultivated on an industrial scale. Kelps have a heteromorphic life cycle characterized by a macroscopic sporophyte and microscopic sexual gametophytes. The sex-dependent effects of different environmental factors on the growth and maturation characteristics of the gametophyte stage were investigated using response surface methodology. Gametophytes were taken from three sites in Japan: Iwate Prefecture, Tokushima Prefecture, and Kagoshima Prefecture in order to confirm the sexual differences in three independent lines. Optimum temperature and light intensity were higher for males (20.7-20.9 °C and 28.6-33.7 µmol m-2 s-1, respectively) than females (16.5-19.8 °C and 26.9-32.5 µmol m-2 s-1), and maturity progressed more quickly in males than females. Optimum wavelengths of light for growth and maturation of the gametophytes were observed for both blue (400-500 nm, λmax 453 nm) and green (500-600 nm; λmax 525 nm) lights and were sex-independent. These characteristics were consistent among the three regional lines. Slower growth optima and progress of maturation could be important for female gametophytes to restrict fertilization and sporophyte germination to the lower water temperatures of autumn and winter, and suggest that the female gametophyte may be more sensitive to temperature than the male. The sexual differences in sensitivity to environmental factors improved the synchronicity of sporeling production.

Rapid toxicity assessment of six antifouling booster biocides using a microplate-based chlorophyll fluorescence in Undaria pinnatifida gametophytes

Biocides of antifouling agents can cause problems in marine ecosystems by damaging to non-target algal species. Aquatic bioassays are important means of assessing the quality of water containing mixtures of contaminants and of providing a safety standard for water management in an ecological context. In this study, a rapid, sensitive and inexpensive test method was developed using free-living male and female gametophytes of the brown macroalga Undaria pinnatifida. A conventional fluorometer was employed to evaluate the acute (48 h) toxic effects of six antifouling biocides: 4,5-Dichloro-2-octyl-isothiazolone (DCOIT), diuron, irgarol, medetomidine, tolylfluanid, zinc pyrithione (ZnPT). The decreasing toxicity in male and female gametophytes as estimated by EC50 (effective concentration at which 50% inhibition occurs) values was: diuron (0.037 and 0.128 mg l-1, respectively) > irgarol (0.096 and 0.172 mg l-1, respectively) > tolylfluanid (0.238 and 1.028 mg l-1, respectively) > DCOIT (1.015 and 0.890 mg l-1, respectively) > medetomidine (12.032 and 12.763 mg l-1, respectively). For ZnPT, 50% fluorescence inhibition of U. pinnatifida gametophytes occurred at concentrations above 0.4 mg l-1. The Undaria method is rapid, simple, practical, and cost-effective for the detection of photosynthesis-inhibiting biocides, thus making a useful tool for testing the toxicity of antifouling agents in marine environments.

Sulfated modification, characterization and monosaccharide composition analysis of Undaria pinnatifida polysaccharides and anti-tumor activity

Undaria pinnatifida (U. pinnatifida) polysaccharides (UPPS) are considered to be the major bioactive components of U. pinnatifida. The aim of the present study was to investigate the separation, sulfated modification, characterization and monosaccharide composition of UPPS. The optimal processing conditions were as follows: Distilled water-to-solid ratio, 50 ml/g; extraction time, 300 min; and extraction temperature, 90˚C. The major polysaccharide fraction of U. pinnatifida (UPPS-B1) was purified via DEAE-52 and Sephadex G-200 column chromatography. The chlorosulfonic acid-pyridine method was applied for sulfation modification. UPPS-B1 and sulfated (S)-UPPS-B1 were characterized via chemical analysis, ultraviolet-visible and Fourier-transformed infrared spectroscopy, gas chromatography and high-performance liquid chromatography. The total sugar content of UPPS-B1 and S-UPPS-B1 was 79.78 and 77.28%, respectively. The sulfate radical content of UPPS-B1 and S-UPPS-B1 was 8.53 and 29.12%, whilst the content of uronic acid was 9.29 and 7.98%, respectively. The average molecular weight of UPPS-B1 and S-UPPS-B1 was determined to be 37 and 110 kD, respectively. UPPS-B1 was considered to be a heteropolysaccharide composed of xylose, mannose, glucose and galactose at a ratio of 7.9:8.7:12.0:9.8. In addition, S-UPPS-B1 was a heteropolysaccharide composed of xylose, mannose, glucose and galactose at a ratio of 1.0:9.7:6.4:1.6. The results of the tumor growth inhibition experiment demonstrated that UPPS-B1 exhibited anti-tumor activity in vivo, which was improved following sulfation to yield S-UPPS-B1.

Structural Dependence of Sulfated Polysaccharide for Diabetes Management: Fucoidan From Undaria pinnatifida Inhibiting α-Glucosidase More Strongly Than α-Amylase and Amyloglucosidase

Fucoidan refers to a group of sulfated polysaccharide that is commonly obtained from various species of brown seaweed. Fucoidan has gained increased popularity among researchers in the recent years due to its numerous biological activities, including its inhibitory effects against starch hydrolyzing enzymes such as α-amylase and α-glucosidase. This highlights the potential of fucoidan as an antidiabetic agent in the management and prevention of diabetes mellitus. In this study, the inhibitory effects of fucoidan isolated from the New Zealand Undaria pinnatifida seaweed species against three starch hydrolyzing enzymes—α-amylase, α-glucosidase, and amyloglucosidase—was investigated. It was demonstrated that while the fucoidan exhibited significant inhibitory effects against all the three starch hydrolases, it is an uncompetitive inhibitor of α-amylase and amyloglucosidase, and is a competitive inhibitor of α-glucosidase. Moreover, it exhibited significantly stronger inhibitory effects against α-glucosidase than α-amylase, thus having the desirable characteristics as an antidiabetic agent.

Oral Fucoidan Attenuates Lung Pathology and Clinical Signs in a Severe Influenza a Mouse Model

Fucoidans are known to be effective inhibitors of inflammation, and of virus binding and cellular entry. Undaria pinnatifida-derived fucoidan (UPF) was assessed in a severe influenza A (H1N1, PR8) infection model in mice. Initially, UPF was gavaged at 3.52 mg daily in a treatment model. Gross lung pathology (consolidation) was significantly reduced as compared to controls. UPF was then presented as a feed supplement at a rate of either nil, 3.52 mg/day or 7.04 mg/day in a prophylactic model, dosed three days before infection. A significant improvement was observed in the clinical signs of ill-health, as well as a reduction in gross lung pathology in animals treated with the higher dose, although there was no significant reduction in lung viral titres.

Physiological and ultrastructural responses of the brown seaweed Undaria pinnatifida to triphenyltin chloride (TPTCL) stress

Triphenyltin chloride (TPTCL) is a well-known marine pollutant that may constitute major environmental threats to seaweed mariculture. In the present study, the toxic effects of TPTCL on physiology and ultrastructure of cultivated sporophytes of Undaria pinnatifida were investigated under different TPTCL concentrations ranging from 0 to 100 μg L-1. Significant negative effects of increased TPTCL concentration were detected in the relative growth rates, survival percentages and chlorophyll a contents of young and adult sporophytes. Low TPTCL concentrations could significantly stimulate the activities of enzymes related to nitrogen metabolism. The chloroplast, mitochondria and nucleus inside cells were greatly damaged by TPTCL. Meanwhile, significant increases of electron dense deposits and physodes were found. Additionally, young sporophytes exhibited greater tolerance to TPTCL stress than adult sporophytes. The results of this study indicate that coastal TPTCL pollution could reduce the productivity and quality of cultivated U. pinnatifida.

Undaria pinnatifida Fucoidan-Rich Extract Recovers Immunity of Immunosuppressed Mice

We investigated the immune restoration activity of Undaria pinnatifida fucoidan-rich extract in cyclophosphamide-induced immunosuppressed mice. C57BL/6 mice were intraperitoneally injected with 80 mg/kg of cyclophosphamide (CP) and orally administered with either drinking water (DW), red ginseng extract (RG), or one of three different doses of Undaria pinnatifida fucoidan-rich extract (DSU02 50, 100, and 150 mg/kg). After 14 days, liver, spleen, and whole blood were isolated from each animal. The frequencies of NK and CD3+, CD4+, and CD8+ T cells were significantly increased in splenocytes isolated from the DSU02 100 mg/kg and DSU02 150 mg/kg groups (NK1.1+, 5.4% or 4.9% vs 3.8%; CD3+, 39.3% or 37.9% vs 32.3%; CD4+, 22% or 20.2% vs 17.4%; CD8+, 12.7% or 11.6% vs 10.1%). NK cytotoxicity was enhanced in the DSU02-fed groups at all doses (CP-treated DW, 93.4%; RG, 107.2%; DSU02 50, 107.3%; DSU02 100, 107.3%; DSU02 150, 107.1%), and the proliferation of T cells (CD3+, CD4+, and CD8+) was also greater in the DSU02 100 mg/kg and DSU02 150 mg/kg administered groups compared with the unfed group. Plasma concentrations of TNF-α, IgM, and total IgG from the DSU02 150 mg/kg group were also significantly higher compared with the other groups (TNF- α: CP-treated DW - 21.5 pg/ml, DSU02 150 - 47.1 pg/ml; IgM: CP-treated DW - 82.9 ng/ml, DSU02 150 - 110.8 ng/ml; total IgG: CP-treated DW - 114.4 ng/ml, DSU02 150 - 162.7 ng/ml). We suggest that Undaria pinnatifida fucoidan-rich extract could be a promising candidate for a marine natural immune stimulator.

Effect of nasal irrigation on allergic rhinitis control in children; complementarity between CARAT and MASK outcomes

Background

Nasal irrigations (NI) are increasingly used as an over-the-counter adjunctive treatment for allergic rhinitis (AR), but clinical studies on their effectiveness are limited.

Methods

An open-label, controlled, non-randomized, real-life study was conducted to evaluate the effectiveness of NI with a new hypertonic solution as add-on treatment for AR. Children and adolescents with AR were prescribed symptomatic treatment. The active group also received an additional sea-water NI solution supplemented with algae extracts. The primary endpoint was symptom control, assessed by the control of allergic rhinitis and asthma test (CARAT) questionnaires. Moreover, the MASK/Allergy Diary was used to track symptoms and daily medication use that were combined in a novel total symptom/medication score (TSMS).

Results

We assessed 76 patients. Overall, there was a significant improvement of CARAT results (median Z-score change of 1.1 in the active/NI group vs. 0.4 in the control group; p = 0.035). Among patients > 12 years old (n = 51), there was a significant improvement in CARAT10 results among participants receiving NI (21.0 to 25.5; p < 0.001), but not in the regular treatment group (21.5 to 24.0; p = 0.100). For children < 12 years old (n = 25), the ΝΙ group had significantly improved symptom control (CARATKids results: 5.0 to 2.0; p = 0.002), in contrast to the control group (4.0 to 2.5; p = 0.057). MASK data on allergic symptoms were comparable between groups. However, the NI group had lower TSMS, more days with < 20% symptoms and fewer days using symptomatic treatment (26.9% vs. 43.5%; p = 0.005).

Conclusion

Addition of NI with a sea-water solution to regular treatment improved AR symptom control. CARAT questionnaires and MASK application can be useful outcome tools in real-life studies.

Effects of Undaria pinnatifida (Wakame) on Postprandial Glycemia and Insulin Levels in Humans: a Randomized Crossover Trial

Postprandial hyperglycemia is a known risk factor for the development of several health disorders, including type 2 diabetes, obesity and cardiovascular disease. This study aimed to investigate the acute effect of Undaria pinnatifida (Wakame), a discriminative constituent of the Japanese diet, on postprandial blood glucose and insulin levels. The study was conducted using a crossover method among 26 subjects. Blood was sampled for glucose and insulin measurements at 0, 30, 60, 90 and 120 min after a subject consumed either 200 g of rice or 200 g rice with 4 g of dried wakame. Blood glucose and insulin levels were significantly lower at 30 min after consuming rice with wakame than after consuming rice alone. Moreover, the incremental areas under the curves for glucose and insulin were lower when wakame was included. Wakame intake can improve postprandial glucose homeostasis. Wakame intake may offer a simple behavioural strategy that can reduce glycemic excursions in prediabetes. This study was registered with the UMIN Clinical Trial Registry (UMIN000031050).

Antimicrobial properties of acrylic resins doped with Undaria pinnatifida exposed to light-emitting diode: In silico and in vitro assessments on multispecies biofilm-producing microbiota

BACKGROUND

This study sought to evaluates the efficiency of anti-microbial activity of acrylic resins doped with different concentrations of Undaria pinnatifida after activation with light-emitting diode (LED) at producing photodynamic damage to multispecies biofilm-producing microbiome.

MATERIAL AND METHODS

In this study, bioinformatics tools and computer simulation molecular modeling were used to evaluate the capacity of ferredoxin (FDX), an electron acceptor in metabolic pathways of U. pinnatifida, which can discharge electrons produced from photo-excited chlorophyll-a (Chl-a) by LED irradiation. Acrylic resin discs containing different concentration of U. pinnatifida (0, 0.5, 1, and 2%) were fabricated and were subjected to LED irradiation immediately before each experiment. After continuously rinsed (up to 30 days), the antimicrobial activity of acrylic resins doped with U. pinnatifida following photo-activation was determined by disc agar diffusion, biofilm formation inhibition, and eluted component assays versus bacterial species linked to caries that constitute a mixed biofilm including Streptococcus mutans, S. sanguinis, and Lactobacillus acidophilus, as well as Candida albicans as main etiology of candidal stomatitis.

RESULTS

Modeling and a virtual screening analysis of FDX indicated that it is a stable protein with an iron-sulfur center that can discharge electrons produced from photo-excited Chl-a and transfers them to FDX-NADP+ reductase for NADP+ reduction in photosystem I, which is essential in the Calvin cycle for carbon assimilation. FDX acts as an electron transfer agent in the redox reactions. The results showed that growth inhibition zones were not seen around acrylic resin discs in any group. In biofilm test, the colony counts of all test microorganisms significantly decreased (36%-87%) by an increase in the percentage of U. pinnatifida in acrylic resins after photo-activation (P < 0.05). Acrylic resins doped with 2% wt. U. pinnatifida following photo-activation using LED was inhibited biofilm formation by the test microorganisms, up to 30 days of rinsing.

CONCLUSION

Based on the results presented here, an acrylic resin containing U. pinnatifida, even at the lowest concentration, following photo-activation using LED have antimicrobial properties against planktonic and biofilm forms of the cariogenic microorganisms as well as C. albicans.

Chemistry and immunostimulatory activity of a polysaccharide from Undaria pinnatifida

An immunologically active polysaccharide named as UPP-2 (1035.52 kDa) was isolated from Undaria pinnatifida using traditional water extraction followed by DEAE Sepharose fast flow chromatography. UPP-2 was proven to be a low sulfated polysaccharide with relatively abundant uronic acid (13.08 ± 0.67%). UPP-2 mainly consisted of xylose (64.55%), glucose (23.81%), arabinose (5.90%) and mannose (4.26%), and its main glycosidic linkage types included →2)-α-D-Xylp-(1→, →4)-α-D-Glcp-(1→, α-D-Xylp-(1→ and →2,4)-β-D-Xylp-(1 → . Results indicated that UPP-2 significantly promoted the proliferation and pinocytic capacity of RAW264.7 cells, and upregulated the mRNA expressions of iNOS, TNF-α, IL-6 and IL-1β at 100-600 μg/mL with a maximum of 195, 42, 768 and 539 times of those of the negative control, respectively. Moreover, UPP-2 significantly increased the secretions of nitric oxide, TNF-α and IL-6 at 100-600 μg/mL (8.0, 73.1 and 188.7 times compared to those of the negative control, respectively), as well as promoted the production of IL-1β obviously at 600 μg/mL. Overall, UPP-2 could be served as a potential dietary supplement or functional food based on its immunostimulatory activity.

Structure characterization and antioxidant activity of fucoidan isolated from Undaria pinnatifida grown in New Zealand

Fucoidan from brown seaweed species, Undaria pinnatifida, has numerous bioactive properties such as antioxidant and anticancer activities. The objective of this research was to quantify the chemical composition of fucoidan isolated from U. pinnatifida harvested in New Zealand and to determine its molecular structure and antioxidant capacity. Crude fucoidan (Fcrude) and purified fucoidan with molecular weight cut off (MWCO) of 300 kDa (F300) were compared against a fucoidan standard (FStd). FStd contained significantly higher sulfate content as compared to Fcrude and F300. Based on FTIR and 2D HSQC analysis, it was proposed that the purified fucoidan was composed of an alternating fucose-galactose backbone linked together via 1,3 glycosidic bonds with sulfation at C2 and C4 positions. Fucoidan samples from New Zealand exhibited secondary antioxidant capacity close to that of butylated hydroxyanisole (BHA), with low-molecular-weight fucoidan had significantly higher capacity than that of BHA.

Arsenic speciation and biotransformation by the marine macroalga Undaria pinnatifida in seawater: A culture medium study

Freshwater and marine organisms are capable of metabolizing arsenic (As) efficiently and regulating the As biogeochemical cycles. In this study, Undaria pinnatifida was exposed to As(V) (0, 0.1, and 1 μM) and phosphate (P; 1 and 10 μM) in seawater under laboratory-controlled conditions for up to seven days to analyze As biotransformation. The growth rates and chlorophyll fluorescence of the alga were unaffected by As stress, and statistically insignificant differences were observed among the cultures (p > 0.05). As(V) was readily accumulated by this macroalga through phosphate transporters, transformed intracellularly, and excreted into the medium, depending on the As(V) to P molar ratios. The concentration of As(V) and biotransformed species As(III) and DMAA(V) varied significantly in the algal cultures on the basis of the exposure period (p < 0.05). The concentration of As(III) was initially higher but decreased with the incubation period, whereas the concentration of DMAA(V) increased gradually. At the end of the incubation, 0.04 and 0.32 μM DMAA(V) were recorded in the media containing 0.1 and 1 μM As(V) with a constant 1.0 μM P, respectively. The results also indicated that the cellular uptake of As(V) and subsequent release of DMAA(V) were inhibited by P in the medium. The biotransformation was consistent with the As(V) detoxification mechanism based on reduction and methylation, which was enhanced by the lower As(V) to P molar ratios. These findings can be helpful in understanding the contribution of macroalgae to As biogeochemistry in marine environments and the potential risks of As dietary intake.

Biocatalysis of Fucodian in Undaria pinnatifida Sporophyll Using Bifidobacterium longum RD47 for Production of Prebiotic Fucosylated Oligosaccharide

Fucosylated oligosaccharide (FO) is known to selectively promote the growth of probiotic bacteria and is currently marketed as a functional health food and prebiotic in infant formula. Despite widespread interest in FO among functional food customers, high production costs due to high raw material costs, especially those related to fucose, are a significant production issue. Therefore, several actions are required before efficient large-scale operations can occur, including (i) identification of inexpensive raw materials from which fucosylated oligosaccharides may be produced and (ii) development of production methods to which functional food consumers will not object (e.g., no genetically modified organisms (GMOs)). Undaria pinnatifida, commonly called Miyeok in Korea, is a common edible brown seaweed plentiful on the shores of the Korean peninsula. In particular, the sporophyll of Undaria pinnatifida contains significant levels of l-fucose in the form of fucoidan (a marine sulfated polysaccharide). If the l-fucose present in Undaria pinnatifida sporophyll was capable of being separated and recovered, l-fucose molecules could be covalently joined to other monosaccharides via glycosidic linkages, making this FO manufacturing technology of value in the functional food market. In our previous work, β-galactosidase (EC 3.2.2.23) from Bifidobacterium longum RD47 (B. longum RD47) was found to have transglycosylation activity and produce FO using purified l-fucose and lactose as substrates (reference). In this research, crude fucodian hydrolysates were separated and recovered from edible seaweed (i.e., U. pinnatifida sporophyll). The extracted l-fucose was purified via gel permeation and ion exchange chromatographies and the recovered l-fucose was used to synthesize FO. B. longum RD47 successfully transglycosilated and produced FO using l-fucose derived from Undaria pinnatifida and lactose as substrates. To the best of our knowledge, this is the first report of synthesized FO using Bifidobacterium spp.

Pathway Analysis of Fucoidan Activity Using a Yeast Gene Deletion Library Screen

Fucoidan, the sulfated fucose-rich polysaccharide derived from brown macroalgae, was reported to display some anti-cancer effects in in vitro and in vivo models that included apoptosis and cell cycle arrest. The proposed mechanisms of action involve enhanced immune surveillance and direct pro-apoptotic effects via the activation of cell signaling pathways that remain largely uncharacterized. This study aimed to identify cellular pathways influenced by fucoidan using an unbiased genetic approach to generate additional insights into the anti-cancer effects of fucoidan. Drug⁻gene interactions of Undaria pinnatifida fucoidan were assessed by a systematic screen of the entire set of 4,733 halpoid Saccharomyces cerevsiae gene deletion strains. Some of the findings were confirmed using cell cycle analysis and DNA damage detection in non-immortalized human dermal fibroblasts and colon cancer cells. The yeast deletion library screen and subsequent pathway and interactome analysis identified global effects of fucoidan on a wide range of eukaryotic cellular processes, including RNA metabolism, protein synthesis, sorting, targeting and transport, carbohydrate metabolism, mitochondrial maintenance, cell cycle regulation, and DNA damage repair-related pathways. Fucoidan also reduced clonogenic survival, induced DNA damage and G1-arrest in colon cancer cells, while these effects were not observed in non-immortalized human fibroblasts. Our results demonstrate global effects of fucoidan in diverse cellular processes in eukaryotic cells and further our understanding about the inhibitory effect of Undaria pinnatifida fucoidan on the growth of human cancer cells.

Effect of polysaccharide from Undaria pinnatifida on proliferation, migration and apoptosis of breast cancer cell MCF7

Sulfated polysaccharide from Undaria pinnatifida (SPUP) has significant anti-breast cancer activity. However, its anticarcinogenic mechanism still remains unclear. The aim of this article is to observe the effect of SPUP on proliferation, migration and apoptosis of human breast cancer cell line MCF7. Firstly, the effect of SPUP on proliferation was evaluated through MTT assay, plate clonality assay and immunofluorescence test of PCNA. The results showed that SPUP could significantly reduce MCF7 cells proliferation in a time- and dose-dependent manner. Based on transwell and scratch wound healing assays, then, inhibitory action of SPUP for MCF7 cells migration was observed. Finally, apoptosis and cycle arrest of SPUP for MCF7 cells also were found by the results from both flow cytometry analysis and Hoechst 33342 staining of apoptotic cells. Overall, these results showed anti-breast cancer mechanism of SPUP could be possibly related to inhibit migration, proliferation and induce apoptosis of cancer cells.

Low Molecular Weight Mannogalactofucans Derived from Undaria pinnatifida Induce Apoptotic Death of Human Prostate Cancer Cells In Vitro and In Vivo

Low molecular weight mannogalactofucans (LMMGFs) prepared by enzymatic degradation of high molecular weight Undaria galactofucan (MF) were evaluated for their anti-cancer effects against human prostate cancer. Correlation NMR and linkage analyses confirmed that LMMGFs consist mainly of α-fucose and β-galactose units: α-fucose units are 1,3-linked; β-galactose units are terminal, 1,3- and/or 1,6-linked; both sugars are partially sulphated, fucose at positions O-2 and/or O-4 and galactose at O-3. Mannose residue, as a minor sugar, presents as the 1,4-linked terminal units. LMMGFs more significantly induced cell cycle arrest at the G0/G1 phase and cell death via suppression of the Akt/GSK-3β/β-catenin pathway than MF in human PC-3 prostate cancer cells. LMMGFs upregulated mRNA expression of death receptor-5 (DR-5), the ratio of Bax to Bcl-2, the cleavage of caspases and PARP, the depolarisation of mitochondrial membrane potential, and ROS generation. LMMGFs (200-400 mg/kg) effectively reduced both tumour volume and size in a xenografted mouse model. These results demonstrated that LMMGFs attenuate the growth of human prostate cancer cells both in vitro and in vivo, suggesting that LMMGFs can be used as a potent functional ingredient in health-beneficial foods or as a therapeutic agent to prevent or treat androgen-independent human prostate cancer. Graphical Abstract.

Between-habitat variability in the population dynamics of a global marine invader may drive management uncertainty

Understanding population dynamics of established invasive species is important for designing effective management measures and predicting factors such as invasiveness and ecological impact. The kelp Undaria pinnatifida has spread to most temperate regions of the world, however a basic understanding of population dynamics is lacking for many regions. Here, Undaria was monitored for 2 years, at 9 sites, across 3 habitats to investigate habitat-related variation in population structure, reproductive capacity and morphology. Populations on marina pontoons were distinct from those in reef habitats, with extended recruitment periods and higher abundance, biomass, maturation rates and fecundity; potentially driven by lower inter-specific and higher intra-specific competition within marinas. This suggests that artificial habitats are likely to facilitate the spread, proliferation and reproductive fitness of Undaria across its non-native range. More broadly, generalising population dynamics of invasive species across habitat types is problematic, thus adding high complexity to management options.

Investigation of Different Molecular Weight Fucoidan Fractions Derived from New Zealand Undaria pinnatifida in Combination with GroA Therapy in Prostate Cancer Cell Lines

Fucoidan, a sulfated polysaccharide extracted from brown seaweeds, has been shown to possess various antioxidant, anticoagulant, antiviral, and anticancer functions. In this study, we focused on low molecular weight fucoidan (LMWF) which was extracted from New Zealand Undaria pinnatifida, and investigated its anti-proliferative effects, combined with a quadruplex-forming oligonucleotide aptamer (GroA, AS1411), a powerful cell surface Nucleolin inhibitor, in prostate cancer cells. We examined LMWF (<10 kDa) and compared it with laboratory grade Fucoidan purchased from Sigma (FS), all extracted from the same seaweed species U. pinnatifida. We found that LMWF significantly improved the anti-proliferative effect of GroA, as it decreased cancer cell growth and viability and increased cell death. This research may provide the foundation for LMWF to be used against prostate cancers as a supplement therapy in combination with other therapeutic agents.

Immune Activation of RAW264.7 Macrophages by Low Molecular Weight Fucoidan Extracted from New Zealand Undaria pinnatifida

Fucoidan, a sulfated polysaccharide extracted from brown seaweeds, has been shown to possess various bioactivities. In particular, low molecular weight fucoidan (LMWF) has been shown to have better bioactivities. In this study, a LMWF (<10 kDa) was extracted from New Zealand Undaria pinnatifida and investigated for its immune modulation effects. LMWF at a concentration range from 1 to 50 μg/mL exerted an effective immune activation in RAW264.7 macrophages. LMWF treatment promoted significant NO release, iNOS expression, and TNF-α and IL-6 secretion in a concentration-dependent manner. It also significantly stimulated the activation of NF-κB and MAPK signaling pathways, and specific inhibitors of NF-κB and MAPK pathways diminished the stimulation, confirming the activation pathways. These results indicate that LMWF possesses potential health benefits through immune-stimulation, which may lead to future pharmaceutical development.

Evaluation Fucoidan Extracts From Undaria pinnatifida and Fucus vesiculosus in Combination With Anticancer Drugs in Human Cancer Orthotopic Mouse Models

OBJECTIVE

To determine the activity of fucoidan from Undaria pinnatifida (UPF) and Fucus vesiculosus (FVF) when given in combination of chemotherapy drugs using selected human breast or ovarian cancer orthotopic mouse models.

METHODS

Mice were inoculated with 1 × 106 cells of TOV-112d, MCF-7, or ZR-75 subcutaneously or SKOV3-GFP-Luc intraperitoneally on day 0. MCF-7 and ZR-75 mice were administered with estradiol valerate 2 mg/kg in 0.2 mL castor oil subcutaneously two days prior to cell inoculation. Mice were randomized to one of six arms (N = 10/arm) paclitaxel, UPF/paclitaxel, FVF/paclitaxel, tamoxifen, UPF/tamoxifen, or FVF/tamoxifen. Tumors were measured three times per week for 28 days.

RESULTS

Improved activity was observed with UPF or FVF in combination with tamoxifen in both the MCF-7 and ZR-75D breast cancer mouse models. Decreased activity of paclitaxel was observed when given in combination with UPF or FVF in both breast cancer mouse models. The combination of FVF/tamoxifen in the TOV-112d ovarian cancer mouse model had improved activity but no there was difference observed with the UPF/tamoxifen in either ovarian cancer mouse model. No difference was observed with combination of UPF or FVF with paclitaxel in human ovarian cancer SKOV3 or TOV-112d orthotopic mouse models.

CONCLUSION

This study did confirm that UPF/FVF in combination with tamoxifen did not decrease tamoxifen activity in both breast and ovarian cancer, with some potential to improve activity compared to tamoxifen alone in breast cancers. Previous in vitro studies had suggested UPF and FVF had overall synergistic activity with paclitaxel; however, in the current in vivo human cancer mouse model studies there was no change in paclitaxel activity when given in combination with UPF or FVF in either of the two human ovarian cancer models. Furthermore, this study demonstrated that UPF or FVF given in combination with paclitaxel had a potential antagonistic effect in breast cancer models. Additional studies are warranted to delineate mechanisms contributing to variation in the in vivo activity when given in combination with paclitaxel. As a first step, a clinical pharmacokinetic study evaluating impact of FVF/UPF given in combination with chemotherapy in patients with solid tumors is underway.

Removal treatments alter the recruitment dynamics of a global marine invader - Implications for management feasibility

Frameworks designed to prioritise the management of invasive non-native species (INNS) must consider many factors, including their impacts on native biodiversity, ecosystem services, and human health. Management feasibility should also be foremost in any prioritisation process, but is often overlooked, particularly in the marine environment. The Asian kelp, Undaria pinnatifida, is one of the most cosmopolitan marine INNS worldwide and recognised as a priority species for monitoring in the UK and elsewhere. Here, experimental monthly removals of Undaria (from 0.2 m2 patches of floating pontoon) were conducted at two marinas to investigate their influence on recruitment dynamics and the potential implications for management feasibility. Over the 18-month experiment there was no consistent reduction in Undaria recruitment following removals. Cleaning of pontoon surfaces (i.e. removal of all biota) led to significant short-term reductions in recruitment but caused a temporal shift in normal recruitment patterns. Non-selective removal (i.e. all macroalgae) generally promoted recruitment, while selective removal (i.e. Undaria only) had some limited success in reducing overall recruitment. The varied results indicate that the feasibility of limiting Undaria is likely to be very low at sites with established populations and high propagule pressure. However, where there are new incursions, a mixture of cleaning of invaded surfaces prior to normal periods of peak recruitment followed by selective removal may have some potential in limiting Undaria populations within these sites. Multi-factorial experimental manipulations such as this are useful tools for gathering quantitative evidence to support the prioritisation of management measures for marine INNS.

Unrevealing variation of microbial communities and correlation with environmental variables in a full culture-cycle of Undaria pinnatifida

Bacteria are the most abundant organisms in natural environment and dominant drivers of multiple geochemical functions. Drawing a global picture of microbial community structure and understanding their ecological status remain a grand challenge. As a typical artificial process, aquaculture provides a large amount of foods and creates great economic benefits for human beings. However, few studies are aimed at the microbial community in the aquaculture environment of aquatic plants. We analyzed microbial communities from 21 water samples in a coastal aquaculture area during the whole cultural process of Undaria pinnatifida by using high-throughout sequencing of 16S rRNA gene. The progression of U. pinnatifida aquaculture can be divided into three stages, named Seeding, Growth, and Maturity, respectively. Microbial community structures in water of the aquaculture area were significantly changed during the progression of U. pinnatifida aquaculture. The relative abundance of Flavobacteriia and Thaumarchaeota classes increased in Growth stage, and β-proteobacteria and Acidimirobiia classes decreased with the growth of U. pinnatifida. Meanwhile, environmental factors shaping the microbial community structures were uncovered during the U. pinnatifida aquaculture by using canonical correspondence analysis and Mantel test, in which temperature, dissolved oxygen, pH and nitrogen could be the major influencing factors. In addition, the microbial functions based on KEGG pathways were predicted from the microbial community compositions by PICRUSt. The comparison of predicted functions suggested that Environmental Information Processing and Genetic Information Processing were the functional categories with the most obvious shift in abundance among different stages of U. pinnatifida aquaculture. The findings of this study allowed us to better understand the microbial community in coastal aquaculture systems and the impact of seaweed cultivation on coastal ecosystems.

Sterepinic Acids A⁻C, New Carboxylic Acids Produced by a Marine Alga-Derived Fungus

Sterepinic acids A⁻C (1⁻3), new carboxylic acids with two primary alcohols, have been isolated from a fungal strain of Stereum sp. OUPS-124D-1 attached to the marine alga Undaria pinnatifida. Dihydro-1,5-secovibralactone (4), a new vibralactone derivative, was isolated from the same fungal metabolites together with known vibralactone A (5), and 1,5-secovibralactone (6). The planar structures of these compounds have been elucidated by spectroscopic analyses using IR, HRFABMS, and NMR spectra. To determine the absolute configuration of the compounds, we used the phenylglycine methyl ester (PGME) method. These compounds exhibited less activity in the cytotoxicity assay against cancer cell lines.

Oral Administration of Edible Seaweed Undaria Pinnatifida (Wakame) Modifies Glucose and Lipid Metabolism in Rats: A DNA Microarray Analysis

SCOPE

Wakame is an edible seaweed that is a common constituent in the Japanese diet. Previous studies showed that wakame consumption is associated with the prevention of metabolic syndrome, but the molecular mechanisms underlying the protective effects are poorly understood.

METHODS AND RESULTS

To determine if the expression of hepatic genes is affected by ingestion of the brown seaweed Undaria pinnatifida (wakame), rats were fed a diet containing 0, 0.1, or 1.0 g per 100 g dried wakame powder for 28 days. Administration of 1% wakame significantly decreased serum total cholesterol levels. Hepatic gene expression was investigated using DNA microarray analysis, and the results showed that wakame suppresses the lipogenic pathway by downregulating SREBF-1. Moreover, bile acid biosynthesis and gluconeogenesis were promoted by upregulation of the PPAR signaling pathway, which leads to a reduction in the accumulation of cholesterol and promotion of β-oxidation.

CONCLUSIONS

These results suggest that wakame ingestion affects glucose and lipid metabolism by altering the expression of SREBF-1 and PPAR signal-related genes.

Rapid physicochemical characterization of innovative fucoidan/fructan powders by ATR-FTIR

Functional food has been highly demanded lately because of its benefits in counteracting diseases. Fucoidan and agave fructan are ingredients that enhance the growth of beneficial bacteria in the gut (prebiotics). This mixture has great potential to develop innovative products but it has never been explored before. Because of fucoidan is more expensive than agave fructan, the innovative proposed mixture is vulnerable to adulteration. This research was aimed to assess the accuracy of Fourier transform infrared spectroscopy with attenuated total reflectance (ATR-FTIR) coupled with chemometrics to identify and predict concentration of both polysaccharides in powder mixtures (0-100%). Absorption bands at 1240-1255 and 836-840 cm-1 were attributed to fucoidan and a strong peak at ~ 936 cm-1 confirmed the fructan presence. Peak areas were best fitted into linear models ( R adj 2  ≥ 0.92, RMSE ≤ 3.54%). This achievement may be useful to certificate ingredients contained in fucoidan-fructan mixtures, preventing adulteration.

Preclinical Evaluation of Safety of Fucoidan Extracts From Undaria pinnatifida and Fucus vesiculosus for Use in Cancer Treatment

OBJECTIVES

To evaluate potential hepatic metabolism-mediated drug interactions with fucoidan from Undaria pinnatifida (UPF) or Fucus vesiculosus (FVF) and potential growth inhibition activity with either fucoidan alone or with chemotherapy. In vivo studies were done to confirm safety and investigate fucoidan-mediated immune modulation.

METHODS

Cytochrome P450 (CYP450) 3A4, 2C8, 2C9, and 2D6 inhibition experiments were conducted in vitro followed by an ex vivo human hepatocytes model to evaluate the CYP450 induction potential of each fucoidan at highest theoretical concentrations. Four hepatic metabolism phase II pathways-glutathione S transferase (GST), quinone oxidoreductase (QOR), catechol-O-methyltransferases (COMT), and uridine di-phosphate (UDP)-glucuronosyltransferase (UGT)-were evaluated with validated immunoassays. Growth inhibition assays were performed with each fucoidan alone and in combination with chemotherapy agents in a panel of human cancer cell lines. In vivo studies evaluated safety and immune modualtion.

RESULTS

CYP450 inhibition was observed with FVF. The GST, QOR, and UGT pathways had no changes. UPF and FVF both interacted with COMT. No growth inhibitory activity in cancer cell lines was observed. UPF and FVF had synergistic activity with paclitaxel or tamoxifen and additive activity with topotecan. In vivo, FVF decreased HeLa human cervical tumor growth and both FVF and UPF decreased TOV-112D human ovarian tumor growth. Otherwise, no significant change in tumor growth was observed. FVF immune modulation of IgG and IL-6 was observed (p<0.03).

CONCLUSION

At higher doses, UPF and FVF may have limited potential for drug-supplement interactions, with either CYP450 or COMT hepatic metabolism pathways. Additional studies are warranted to evaluate to confirm findings of fucoidans in combination with chemotherapy.

A review of three decades of research on the invasive kelp Undaria pinnatifida in Australasia: An assessment of its success, impacts and status as one of the world's worst invaders

Marine invasive macroalgae can have severe local-scale impacts on ecological communities. The kelp Undaria pinnatifida is one of the most successful marine invasive species worldwide, and is widely regarded as one of the worst. Here, we review research on Undaria in Australasia, where the kelp is established throughout much of New Zealand and south-eastern Australia. The presence of Undaria for at least three decades in these locations makes Australasia one of the longest-invaded bioregions globally, and a valuable case study for considering Undaria's invasion success and associated impacts. In Australasia, Undaria has primarily invaded open spaces, turf communities, and gaps in native canopies within a relatively narrow elevation band on rocky shores. Despite its high biomass, Undaria has relatively few direct impacts on native species, and can increase community-wide attributes such as primary productivity and the provision of biogenic habitat. Therefore, Australasian Undaria research provides an example of a decoupling between the success and impact of an invasive species. Undaria will most likely continue to spread along thousands of kilometres of rocky coastline in temperate Australasia, due to its tolerance to large variations in temperature, ability to exploit disturbances to local communities, and the continued transfer among regions via vessel movements and aquaculture activities. However, the spread of Undaria remains difficult to manage as eradication is challenging and seldom successful. Therefore, understanding potential invasion pathways, maintaining native canopy-forming species that limit Undaria success, and effectively managing anthropogenic vectors of Undaria spread, should be key management priorities.

Protective Effects of Mekabu Aqueous Solution Fermented by Lactobacillus plantarum Sanriku-SU7 on Human Enterocyte-Like HT-29-luc Cells and DSS-Induced Murine IBD Model

Most wakame Undaria pinnatifida, a brown algae, products are made from the frond portion. In this study, the polysaccharide content and antioxidant property of aqueous extract solutions (AESs) of the four parts (frond: wakame, stem of the frond: kuki-wakame, sporophyll: mekabu, and kuki-mekabu) of wakame were investigated. Polysaccharide content was high in both the wakame and mekabu. Superoxide anion (O2-) radical-scavenging capacities were high in the mekabu. These AESs could be fermented by Lactobacillus plantarum Sanriku-SU7. The O2- radical-scavenging activity of the kuki-wakame, mekabu, and kuki-mekabu were increased by the fermentation. Fermented mekabu clearly showed a protective effect on human enterocyte-like HT-29-luc cells and in a mouse model of dextran sodium sulphate-induced inflammatory bowel disease (IBD). These results suggest that the mekabu fermented by L. plantarum Sanriku-SU7 has anti-IBD effect related to O2- radical-scavenging.