Brown Seaweed Species Research Articles

Optimisation of biogas generation from brown seaweed residues: Compositional and geographical parameters affecting the viability of a biorefinery concept

Very recently, integrated biorefinery approaches are being developed with the aim to produce high-value products for a variety of industries in conjunction with green energy from sustainable biomass. Macroalgae (seaweed) have been regarded as more sustainable compared to terrestrial crops, since they do not occupy land for growth. Macroalgal biomass changes greatly according to species and harvest season, which affects its chemical energy potential. This study was conducted seasonally on five species of brown seaweed over a yearlong period to investigate the effects of chemical composition variations, bioproducts extraction processes and inoculum acclimatation on methane production. As a result of the bioproducts extraction, it was found the seaweed residues exhibit a great potential to produce methane. Stoichiometric methane yield and C:N ratio changed in favour of an improved digestibility with bioconversion rates greater than 70% in some instances, i.e. achieved by Laminaria species and on the West coast Fucus serratus. The two Laminaria species investigated also presented the highest CH4 production rate, with Laminaria digitata reaching 523 mL CH4 gVS−1 and L. saccharina peaking at 535 mL CH4 gVS−1 with acclimatised and non-acclimatised sludge respectively.

Fucoidan Inhibits Vascular Remodeling in Transplant Vasculopathy in Rat

Background: Fucoidan is a natural sulfated polysaccharide which exists mainly in the cell wall matrix of various species of brown seaweed. Various forms of fucoidan have also been recognized in some marine invertebrates such as sea urchins and sea cucumbers.Fucoidan inhibits the spread of cancerous cells by preventing the adhesion of tumor cells to the extracellular matrix in addition to inducing apoptosis, or programmed self-destruction, in human T-cells infected by T-cells leukemia virus type I (HTLV-1) which causes adult T-cell leukemia. The polysaccharide has also been shown to stimulate the phagocytic action of macrophages and synthesis of several immune cell types, which increases protection against infection. Fucoidan gives the immune system a big boost by enhancing phagocytosis. Additionally, it increases the number of mature white blood cells which are circulating in the body, thereby bolstering the first line of defense against infections and diseases.Moreover, fucoidan has anti-coagulant, anti-thrombotic, anti-inflammatory, antioxidant, anti-allergic, anti-tumor properties and also many others.Methods and Results: In this study, we investigated whether fucoidan is able to alleviate the vascular remodeling process triggered by immunological stimuli in rat allogenic aorta transplantation model, in addition to the evaluated potential mechanisms responsible for the observed effects. Our rat aorta transplantation model was subjected to intraperitoneal or oral treatment with fucoidan or placebo. The results of our study demonstrated that fucoidan inhibits endointimal hyperplasia formation and vascular modulation. In particular, intraperitoneal and oral administration of fucoidan reduced neointima formation in allografts retrieved 8 weeks after transplantation. Moreover, both treatments with fucoidan reduced the number of smooth muscle (SM) a-actin positive cells in intima and adventitia, decreased percentage of macrophages in intima and media, and increased the number of leukocytes in media of the allografts. Fucoidan treatments have also caused reduction in apoptosis in allograft intima and media.Conclusion: Through our study, we demonstrated the inhibitory effect of fucoidan on vascular remodeling in transplant vasculopathy within rats. Our study is the first report of the beneficial effects of fucoidan oral administration on this process, which may have important clinical implications and result in a better understanding of vascular remodeling. Keywords: fucoidan, transplant vasculopathy, vascular remodeling

Seaweeds from the Portuguese coast as a source of proteinaceous material: Total and free amino acid composition profile

The total protein content and the (total and free) amino acid composition of nine edible species of red, brown and green seaweeds collected in the Portuguese North-Central coast were quantified to assess their potential contribution to the recommended dietary intake. Whenever possible, the protein and amino acid composition was compared with that of commercial European seaweeds. The protein content was the highest (P < 0.05) in red species (19.1–28.2 g/100 g dw), followed by the green seaweed Ulva spp. (20.5–23.3 g/100 g dw), with the lowest content found in brown seaweeds (6.90–19.5 g/100 g dw). Brown seaweeds presented the lowest mean contents of essential amino acids (EAAs) (41.0% protein) but significantly (P < 0.05) higher concentrations of non-essential amino acids (36.1% protein) and free amino acids (6.47–24.0% protein). Tryptophan, methionine and leucine were the limiting EAAs in all species. In contrast, lysine was found in high concentrations, especially in red (2.71–3.85% protein) and green (2.84–4.24% protein) seaweeds.

Edible brown seaweeds: a review

Seaweeds play a vital role as a source of food and ingredients in traditional Korean medicine. Koreans consume seaweed as fresh vegetables, salad, soups, or snacks. There are several edible brown seaweed species are abundant along the shores of the Korean peninsula, such as Ecklonia cava, Hizikia fusiforme, Laminaria japonica, Pelvetia siliquosa, Sargassum fulvellum, and Undaria pinnatifida. With the growing body of scientific evidence, it is clear that these brown seaweeds are not only good substitutes for land vegetables but also a good source of bioactive secondary metabolites. The secondary metabolites identified from edible Korean brown seaweeds (phlorotannins, sulfated polysaccharides, pigments, and sterols) have the potential to be developed as functional food ingredients. However, seaweeds consumption and their industrial level applications as functional materials are limited compared to the land vegetables. Insufficient awareness about health benefits of seaweeds might be the reason for this issue. Thus, in this review health promotion properties associated with edible Korean brown seaweeds are summarized. The present study might therefore increase consumption and industrial use of brown seaweeds.

Identification and characterization of the fucoidanase gene from Luteolibacter algae H18

Fucoidan is a hetero-sulfated polysaccharide found in brown algae and has received much attention as an ingredient in functional and health foods. The marine bacterial strain Luteolibacter algae H18 degrades fucoidan from Cladosiphon okamuranus. We purified the fucoidanase from a cell-free extract of L. algae H18, used it to decrease the molecular weight of deacetylated-fucoidan, determined the N-terminal amino acid sequence of the enzyme, and identified the gene involved in the degradation of fucoidan, fct114, in a draft genome sequence of strain H18. The gene product was heterologously produced in Escherichia coli and demonstrated to catalyze the degradation of deacetylated-fucoidan into lower molecular weight fragments. The mass of the gene product Fct114 is 112kDa (1026 amino acid residues). The general properties of the enzyme were investigated by measuring the amount of reducing ends produced from deacetylated-fucoidan during the reaction. The enzyme was inactive toward fucoidans from other brown seaweed species or toward polysaccharides such as alginic acid, carrageenan, hyaluronic acid, and chondroitin sulfate. The amino acid sequence of Fct114 shared less than 25% identity and had no conserved motifs when compared with previously identified fucoidanases from other marine bacterial strains. These data suggest that Fct114 is a novel polysaccharide-degrading enzyme.

Effects of Enriching Nitrogen and Phosphorus on the Growth of Sargassum Podacanthum Cultured in Potassium-Fortified Inland Saline Water

Potassium-fortified inland saline water (K+ISW) has shown potential for growing marine species, including seaweed species. The response of a brown seaweed species, Sargassum podacanthum, to nitrogen and phosphorus enrichments were evaluated by culturing the species for 84 days in K+ISW and comparing it with Ocean Water (OW). The culture media was enriched weekly with ammonium chloride and sodium dihydrogen phosphate, with ammonium and phosphate ratios of 10:1 at five different concentrations 80:8, 120:12, 160:16, 200:20 and 240:24 μM. The culture medium with no enrichment was used as a control. The water quality and biomass of S. podacanthum were measured fortnightly. The S. podacanthum biomass increase significantly with different concentrations of the nutrient supplementations. The standing biomass and Specific Growth Rate (SGR) of S. podacanthum were similar in OW and K+ISW in the absence of any nutrient supplementation and at the supplement concentration of ammonium and phosphate 160:16 μM. However, from day 42 onwards, at the ratios of 80:8, 120:12, 200:20 and 240:24, S. podacanthum cultured in OW grew significantly faster than in K+ISW. In K+ISW, optimal growth of S. podacanthum was observed at the 160:16 and the increase in biomass was significantly higher than the initial biomass until day 70, whereas at the other four nutrient supplement concentrations, the S. podacanthum biomass remained unchanged during the entire culture period. The nitrite, total Kjeldahl nitrogen and phosphate concentrations in water were found to be significantly (p<0.05) and negatively correlated (p<0.05) with S. podacanthum biomass. Therefore, the results showed that the enrichment of 160 μM ammonium and 16 μM phosphate is required in the K+ISW for S. podacanthum to achieve optimal growth.

In vitro investigating of anticancer activity of focuxanthin from marine brown seaweed species

Breast cancer is the most common cancer type among women all over the world. Chemotherapy is the use of anticancer medicines for treating cancer but it has many side effects and cells may become resistant to these chemical medicines. Therefore, finding new compounds of natural origin could be a promising solution to this problem. The aim of the current study was to evaluate anticancer activity of fucoxanthin which is the most important carotenoid found in the marine brown seaweeds and diatoms. fucoxanthin has many properties (antioxidant, antibacterial, anticancer, antiobesity, anti-inflammatory and etc.) due to its unique structure. Samples with different concentrations (10, 25 and 50 µg/ml) and at various incubation times were collected (6, 24 and 48 hours) from four different species (Padina tenuis, Colpomenia sinuosa, Iyengaria stellate and Dictyota indica) of brown seaweeds from Qeshm Island, Persian Gulf. Moreover, the anticancer activity of fucoxanthin-containing extracts on breast cancer cells line and normal human skin fibroblast cells line was assessed by MTT [3-(4,5-dimethylthiazolyl)-2,5-diphenyl-tetrazolium bromide] assay to specify the cytotoxic effects. The results showed that fucoxanthin extract from Dictyota. indica at 24-hour treatment and 50 µg/ml concentration has the most effective anticancer activity on the breast cancer cells line, without toxic effects to the normal cells. According to the obtained results, it seems that Dictyota. Indica is a good candidate for further analysis and can be introduced to the food and pharmaceutical industries.

Monascus spp. fermented brown seaweeds extracts enhance bio-functional activities

Abstract Two species of brown seaweeds, Saccharina japonica and Undaria pinnatifida were fermented by the red molds; Monascus purpureus and Monascus kaoliang to increase their bio-functional properties. The phenolic contents of S. japonica fermented by M. purpureus (SjMp) and M. kaoliang (SjMk) were the highest 71.53 ± 2.25 and 66.50 ± 4.64 mg gallic acid equivalent/g extract, respectively, whereas the highest flavonoid content was evident in S. japonica fermented by M. purpureus (SjMp) and U. pinnatifida fermented by M. purpureus (UpMp) (27.93 ± 0.28 and 26.88 ± 1.24 mg quercetin equivalent/g extract, respectively). Reducing sugar, protein and essential fatty acids levels also increased in fermented seaweeds. The antioxidant activities of fermented seaweed extracts exhibited significantly (p

The invasive kelp Undaria pinnatifida hosts an epifaunal assemblage similar to native seaweeds with comparable morphologies

Invasive seaweeds have the potential to disrupt ecosystem functioning if they are unsuitable hosts for the small mobile invertebrates (epifauna) that are an important trophic link between benthic primary producers and higher trophic levels. The Asian kelp Undaria pinnatifida has successfully invaded many coastal regions worldwide. We compared the epifaunal assemblage on U. pinnatifida with epifauna of 7 co-occurring, canopy-forming native brown seaweed species in southern New Zealand to help understand the effect of the invasive species on shallow subtidal ecosystems. The density, diversity and composition of epifauna across the 8 seaweeds were much more strongly related to host morphology than to the geographic origin of the host. U. pinnatifida and several native seaweeds with similarly simple morphologies supported relatively depauperate epifaunal assemblages dominated by copepods. More structurally complex native seaweeds supported more abundant and diverse epifaunal assemblages containing lower proportions of copepods and higher proportions of amphipods and other epifaunal groups. Our results indicate that abundances of epifauna at the ecosystem level will be reduced if U. pinnatifida displaces more structurally complex native seaweed species that host more diverse and dense epifaunal assemblages. The findings suggest that morphological complexity may be key to predicting the impacts of invasive seaweeds on epifaunal assemblages, and potentially on food webs, in other geographic regions.

Evaluation of bioactivity of fucoidan from laminaria with in vitro human cell cultures (THP-1)

Background: Seaweeds represent one of the few remaining food sources available globally which are not being fully utilized or even over utilized. Kelps (Laminaria spp.) are one of the numerous species of brown seaweeds, a popular marine vegetable, which has been used as a source of iodine and minerals for centuries. Kelps contain anionic polysaccharides called fucoidans heteroglycans with L – fucose units. Their monosaccharide composition, physicochemical and bioactive properties vary between seaweed species. The objective of this work was to evaluate the bioactive properties of laminaria fucoidan (L. digitata and L. hyperborea) toward THP–1 macrophages, a human macrophage like cell line, and investigate its potential antioxidant and immunomodulatory characteristics.Methods: THP-1 macrophages were incubated with five fucoidan concentrations. The Oxygen Radical Absorbance Capacity (ORAC) assay was determined for cell lysates and for the fucoidan extract, in addition to Total Polyphenol Content (TPC). Cytotoxicity of fucoidan was assessed by light microscopy, followed by XTT proliferation assay. Enzyme–linked immunosorbant assays (ELISA) were performed to determine concentrations of the secreted tumor necrosis factor α (TNF-α), interleukin 6 (IL–6), and interleukin 10 (IL–10). Results: Fucoidan did not affect macrophage ability to scavenge oxygen radicals (ORAC) confirming its antioxidant properties toward activated macrophages. The laminaria fucoidan extract at 100 µg/ml concentration lowered macrophage viability. Lower concentrations of laminaria fucoidan did not have impact on cell viability. Very low concentration of fucoidan at 0.1 µg/ml triggered secretion of TNF-α. However, IL–6 and interleukin IL–10 were expressed when concentration of applied fucoidan was 10 µg/ml indicating bioactivity of laminaria fucoidan through immunomodulatory actions.Conclusions: The study demonstrated how laminaria fucoidan may have bioactive properties towards THP–1 macrophages. Changes in cytokine secretion between pro–inflammatory (TNF–α, and IL–6) and anti–inflammatory (IL–10) cytokines confirmed bioactivity of the laminaria fucoidan extracts.Keywords: Seaweeds, Kelps, Laminaria, fucoidan, bioactivity, macrophages

Fucoidan from Fucus vesiculosus suppresses hepatitis B virus replication by enhancing extracellular signal-regulated Kinase activation

BackgroundHepatitis B virus (HBV) infection is a serious public health problem leading to cirrhosis and hepatocellular carcinoma. As the clinical utility of current therapies is limited, the development of new therapeutic approaches for the prevention and treatment of HBV infection is imperative. Fucoidan is a natural sulfated polysaccharide that extracted from different species of brown seaweed, which was reported to exhibit various bioactivities. However, it remains unclear whether fucoidan influences HBV replication or not.MethodsThe HBV-infected mouse model was established by hydrodynamic injection of HBV replicative plasmid, and the mice were treated with saline or fucoidan respectively. Besides, we also tested the inhibitory effect of fucoidan against HBV infection in HBV-transfected cell lines.ResultsThe result showed that fucoidan from Fucus vesiculosus decreased serum HBV DNA, HBsAg and HBeAg levels and hepatic HBcAg expression in HBV-infected mice. Moreover, fucoidan treatment also suppressed intracellular HBcAg expression and the secretion of the HBV DNA as well as HBsAg and HBeAg in HBV-expressing cells. Furthermore, we proved that the inhibitory activity by fucoidan was due to the activation of the extracellular signal-regulated kinase (ERK) pathway and the subsequent production of type I interferon. Using specific inhibitor of ERK pathway abrogated the fucoidan-mediated inhibition of HBV replication.ConclusionThis study highlights that fucoidan might be served as an alternative therapeutic approach for the treatment of HBV infection.

Effect of Hydrolyzed Fucoidan from The Brown Seaweed Sargassum Binderi Sonder Towards Human Breast Cancer T47d Cell Lines

Fucoidan, a sulfated heteropolysaccharide, consists of L-fucose and sulfate ester groups as the main component. Over the past three decades, fucoidan structures and bioactivities have been widely studied. The chemical components (fucose, galactose, small monosaccharides and also the sulfate) and the molecular weights of fucoidans from different brown seaweed species produce different characteristics and structures of fucoidan. The activity of fucoidan against cancer cells has been reported to be affected strongly by their sulfate content and molecular weight. Low-molecular-weight fucoidans tend to have higher solubility and easily penetrate into cancer cells. The objective of this study was to investigate the effect of hydrolyzed of fucoidan on its anti cancer activity againts the breast cancer T47D cells. In this study, the fucoidan from the brown seaweed Sargassum binderi Sonder was extracted using 0.1 N HCl and was depolymerized by acid hydrolysis at various times and concentrations. Result showed that fucoidan hydrolyzed with 1 M trifluoroacetic acid (TFA) for 1.5 hours reached the maximum depolymerization process and resulted in the decrement of molecular weight from 785.12 kDa to 5.79 kDa as well as sulfate content from 18.63% to 8.69%. The IC50 values of fucoidan and low molecular weight fucoidan against the breast cancer T47D cells were 60.03 mg/mL and 182.34 mg/ respectively. This result indicated that the sulfate content of fucoidan probably affected its anticancer bioactivities.

O24 Functionality of selected seaweed extracts on selected pharmaceutical applications

Cosmetic and pharmaceutical industry is looking more and more for natural marine compounds with key identified bioactivities. The Laboratoires Gilbert are a major French industrial player developing natural origin products in cosmetic and pharmacy markets. ALGAIA is a French company providing R&D services and natural extracts from macro- and micro-algae. The present study is based on a private close collaboration between the Laboratoires Gilbert and ALGAIA. The main approach has been to extract, characterise and test bioactivities of novel seaweed extracts towards cosmetic and pharmaceutical applications. In the overall work, 1 green species, 2 red species and 3 brown seaweed species have been used as starting material for creating more than 50 different extracts. After characterization, these extracts have been screened for different bioactivities, each one implemented with different techniques. In the present work, some of the outcomes related to the brown seaweed species studied will be presented and discussed. The focus will be made between the main composition of the selected extracts including polysaccharides and phenolic compounds and their anti-inflammatory and wound healing activities in particular. The composition between the three species is by nature different but also the compounds extracted vary also by their yields and size, depending on the extraction process used. As a consequence, in our study, the results on each bioactivity tested show different levels and scope of action dependent upon the extract that has been tested. Those results will be presented and discussed in order to propose hypotheses of actions and constitute a strong base for sustainable development of innovative pharmaceutical products based on active seaweed extracts.

Differences in Metal Accumulation in the Growing Shoot Tips and Remaining Shoot Tissue in Three Species of Brown Seaweeds.

In this study we compared the accumulation of eight metals and two metalloids in the growing tips and the remaining shoot tissue of three species of brown seaweeds commonly used in biomonitoring studies (Fucus ceranoides, Fucus spiralis and Ascophyllum nodosum). Regression analysis of the data obtained showed that there was no statistically significant difference in accumulation in numerous cases; although most of the relationships were significant, many of the coefficients of determination were low. However, the concentrations of Mn and Zn in the growing tips were closely related to the concentrations in the rest of the tissue in all three species, possibly due to redistribution of these elements. Interspecies differences in bioconcentration of the elements may be partly explained by differences in the relative growth rates.

Abstract 5848: Fucoidan adminstration attenuates radiation pneumonitis and fibrosis through reducing inflammatory cytokine expression in lung tissue

Abstract Purpose: There is no well-known compound to prevent radiation pneumonitis (RP) or prophylactically use to attenuate the toxicity of RP. RP is one of major complications in chest part irradiation and limitations of radiation dose. Fucoidan is a sulfated polysaccharide found mainly in various species of brown algae and brown seaweed. Recent studies have demonstrated its anti-inflammation effect. Since RP is an radiation induced inflammatory and fibrosis related complication, we investigated the effect of fucoidan adminstration on radiation pneumonitis and fibrosis. Materials and Methods: In this study, we compared the pneumonitis and fibrosis in lung tissue specimen between the lungs irradiated (10Gy/one shot) C57BL/6 mice with or without Fucoidan adminstration (200mg/kg /day, oral gavage for 14 days). Results: The results demonstrated that fucoidan adminstration attenuates pneumonitis and fibrosis in lung tissue. We found the accumulation of neutrophils in irradiated lung tissue was decreased, and the radiation induced Masson trichrome staining fibrosis was decreased. We also investigate the inflammatory -cytokine profiles in the irradiated lung tissue by protein array. The results revealed that fucoidan adminstration changes the inflammatory -cytokine expression pattern in in the irradiated lung tissue. Conclusions: This study demonstrated that inflammatory -cytokine expression after whole lung irradiation is correlated with neutrophil accumulation and radiation induced fibrosis. Interestingly, Fucoidan adminstration changes the inflammatory -cytokine expression pattern which may lead to attenuates radiation pneumonitis and fibrosis. It is potential to be a therapeutic molecular to attenuate or prevent radiation pneumonitis. Note: This abstract was not presented at the meeting. Citation Format: Szu-Yuan Wu. Fucoidan adminstration attenuates radiation pneumonitis and fibrosis through reducing inflammatory cytokine expression in lung tissue [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5848. doi:10.1158/1538-7445.AM2017-5848

Influence of The Extract of Brown Seaweed (Turbinaria decurrens Bory) on the Histology of Colon on AOM-DSS Mouse Model

Utilization of seaweed as a commodity trading or as a raw materials industry is still relatively small compared with the diversity of seaweed species in Indonesia. Turbinaria decurrens Bory is one of the brown seaweed species that has a high enough fucoxanthin content compared with other brown seaweed species. Fucoxanthin is one of the carotenoid pigments that have long been known to have bioactivity as anti-inflammatory, antioxidant and anticarcinogenic that can neutralize free radicals. Therefore, in this study, we evaluated another function of Turbinaria decurrens Bory as a candidate for colon cancer drug. To this end, we used 36 Male Swiss Webster mice aged 5-6 weeks and divided into six groups. Group I as normal groups, Group II as AOM-DSS induced cancer group, Group III as Aspirin treated group; Group IV-VI Brown Seaweed extracts dose 1 to 3 are 3.61; 7.22; 14.41 mg/kg body weight, respectively. All groups except normal group treated by 12.5 mg/kg body weight of AOM by intraperitoneal injection followed by two cycles of DSS treatment and five days for each treatment. At the end of the experiment, mice sacrificed and the colon was isolated and subject to histology treatment. As a result, showed that AOM-DSS could make colon cancer in all mice. The administration of brown seaweed extract at the dose I could prevent the development of cancer. Increasing dose could not prevent better, but it makes worst.

Phenolic compounds from three brown seaweed species using LC-DAD–ESI-MS/MS

The phenolic compounds of extracts from Ascophyllum nodosum (ANE), Bifurcaria bifurcata (BBE) and Fucus vesiculosus (FVE) from Galicia (NW Spain) were analyzed by liquid chromatography-diode array detection coupled to negative electrospray ionization-tandem mass spectrometry (LC-DAD–ESI-MS/MS) with the interest to evaluate their potential application as functional ingredients. Phlorotannins were tentatively identified as the main phenolic compounds in the three extracts, followed by phenolic acids, and flavonoids. Fuhalols were present in ANE and BBE, while hydroxyfuhalols were identified in BBE and FVE. Eckol derivatives were present in the three extracts. Quinic acid derivatives were tentatively identified in the three seaweed species; in addition, ANE showed specifically hydroxybenzoic and rosmarinic acid derivatives, BBE showed rosmarinic acid, and FVE contained p-coumaric and ferulic acid derivatives. Regarding flavonoids, acacetin derivatives were tentatively identified in the three extracts, hispidulin and a gallocatechin derivative were specifically detected in ANE, and cypellocarpin C was present in BBE. In conclusion, all brown seaweed extracts studied could be exploited as sources of antioxidant phenolic compounds with potential applications in the food and health sectors.

Optimization of spray drying process of Sargassum muticum color extract

ABSTRACTSargassum muticum is categorized as a brown seaweed species which has been used as a dye fabric colorant in certain regions of Asia. The brown extracts of S. muticum also have antioxidant properties, which could enhance the color and nutrients in food products. However, the color extract is unstable, and also limits the application. This study was performed to encapsulate the color extract with maltodextrin and stabilize the color extract by spray drying technique using combinations of various levels of inlet temperature and feed flow rate. Initially, S. muticum powder was analyzed for moisture content, water activity, solubility, and color properties for optimization purposes. This study showed that the optimum inlet temperature and feed flow rate of the spray drying process to produce good-quality, stable, and acceptable powder properties were at 140°C and 3 rpm, respectively, with 4% of maltodextrin. Then, the powder was analyzed for density, compressibility index, hygroscopicity, particle size, and antioxidant properties. This study represents an interesting food additive to be incorporated in functional food due to the attractive brown colorant and the presence of antioxidants.

Co-digestion of terrestrial plant biomass with marine macro-algae for biogas production

This paper investigates factors affecting anaerobic degradation of marine macro-algae (or seaweed), when used as a co-substrate with terrestrial plant biomass for the production of biogas. Using Laminaria digitata, a brown marine seaweed species and green peas, results showed that when only 2% of feedstock of a reactor treating the green peas at an organic loading rate (OLR) of 2.67 kg VS m3 day−1 was replaced with the seaweed, methane production was disrupted, whilst acidogenesis, seemed to be less adversely affected, resulting in excessive volatile acids accumulation. Reactor stability was difficult to achieve thereafter. The experiment was repeated with a lower initial OLR of green peas of 0.70 kg VS m3 day−1 before the addition of the seaweed. Although similar symptoms as in first trial were observed, process stability was restored through the control of OLR and alkalinity. These measures led to an increase in overall OLR of 1.25 kg VS m3 day−1 comprising of 35% seaweed. This study has shown that certain seaweed constituents are more inhibitory to the methanogens even at trace concentrations than to the other anaerobic digestion microbial groups. Appropriate adaptation strategy, involving initial low proportion of the seaweed relative to the total OLR, and overall low OLR, is necessary to ensure effective adaptation of the microorganisms to the inhibitory constituents of seaweed. Where there is seasonal availability of seaweed, the results of this study suggest that a fresh adaptation or start-up strategy must be implemented during each cycle of seaweed availability in order to ensure sustainable process stability.

Arctic marine phytobenthos of northern Baffin Island.

Global climate change is expected to alter the polar bioregions faster than any other marine environment. This study assesses the biodiversity of seaweeds and associated eukaryotic pathogens of an established study site in northern Baffin Island (72° N), providing a baseline inventory for future work assessing impacts of the currently ongoing changes in the Arctic marine environment. A total of 33 Phaeophyceae, 24 Rhodophyceae, 2 Chlorophyceae, 12 Ulvophyceae, 1 Trebouxiophyceae, and 1 Dinophyceae are reported, based on collections of an expedition to the area in 2009, complemented by unpublished records of Robert T. Wilce and the first‐ever photographic documentation of the phytobenthos of the American Arctic. Molecular barcoding of isolates raised from incubated substratum samples revealed the presence of 20 species of brown seaweeds, including gametophytes of kelp and of a previously unsequenced Desmarestia closely related to D. viridis, two species of Pylaiella, the kelp endophyte Laminariocolax aecidioides and 11 previously unsequenced species of the Ectocarpales, highlighting the necessity to include molecular techniques for fully unraveling cryptic algal diversity. This study also includes the first records of Eurychasma dicksonii, a eukaryotic pathogen affecting seaweeds, from the American Arctic. Overall, this study provides both the most accurate inventory of seaweed diversity of the northern Baffin Island region to date and can be used as an important basis to understand diversity changes with climate change.