Tag: Seaweed

Reports

Distribution of arsenic species by seaweed parts, especially arsenic lipids

Published:

02/04/2024

Authors:

Rebecca Sim, Ásta H. Pétursdóttir, Natasa Desnica, Jörg Feldmann, Guðmundur Haraldsson, Karl Gunnarsson, Liberty O'Brien, Marta Weyer and Hildur I. Sveinsdóttir.

Supported by:

Icelandic Research Fund

Contact

Rebecca Sim

Ph.D. Student

rebecca@matis.is

Distribution of arsenic species within the macroalgae 
– an emphasis on arsenolipids

Algae are rich in minerals and desirable bioactive substances, but they can also absorb large amounts of trace elements, such as toxic heavy metals, including the element arsenic. Arsenic is found as inorganic arsenic in the sea and is taken up in that chemical form by the algae. In the algae, however, arsenic is detected not only as inorganic arsenic but as a wide range of arsenic compounds, so-called organic compounds of arsenic, for example arsenosaccharides and arsenolipids. There is still a lot of mystery about the origin of these compounds. In general, organic forms of arsenic have been considered quite harmless, unlike inorganic arsenic, which is a known carcinogen. However, recent studies on arsenolipids have shown that they can be as cytotoxic as inorganic arsenic. It is also believed that arsenosugar can possibly have long-term negative effects with regular consumption. Levels of arsenolipids are generally not high in algae, but the starting point of their production is thought to occur in algae. Algae are part of the regular food intake in the Eastern part of the world and are becoming increasingly popular in the West, so more information about these compounds is urgently needed to fully assess the risks associated with their consumption as well as to ensure that appropriate regulations are put in place regarding their maximum levels in foodstuffs. In order to understand the toxicological effects of algae consumption, it is extremely important that more data be collected on all the different chemical forms of arsenic, in particular on arsenolipids, but limited information is currently available on them. Samples of red, green and brown algae were collected near Grindavík and Kjalarnes, at two different points in time. The samples were thoroughly analyzed for heavy metals and arsenic analysis was carried out to better understand the chemical form in which the arsenic was present. Selected samples of brown, red and green algae were measured for species analysis of arsenolipids using mass spectrometry HPLC-ICP-M/ESI-MS/MS and HPLC-qToF-MS. In addition, brown macroalgae were divided into biological fractions to determine whether the distribution of arsenic species is uniform throughout the seaweed. Limited information exists globally on arsenolipids in seaweed, so this extensive profiling of them in different species of algae will help elucidate how these enigmatic organic compounds are formed and where they are stored. The data can also be used for risk assessment of arsenic species in seaweed for human consumption and can therefore influence future food safety legislation.
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In recent years seaweed has gained popularity as a health food due to its high content of minerals and vitamins. However, seaweeds may also accumulate high levels of potentially toxic elements – in particular arsenic, which may become incorporated into larger biological molecules such as sugars and lipids. It is unclear how these organic arsenic compounds are formed/stored and if they may serve a biological purpose (ie, detoxification or energy storage). However, toxicological studies into arsenic-containing lipids have demonstrated cytotoxicity comparable to that of arsenite, a known carcinogen, and arsenic-containing sugars are suspected to display toxicity with chronic exposure. This project aims to investigate variations in the distribution of arsenic compounds throughout several classes and species of seaweed. Samples of brown, red and green macroalgae were collected from two locations in Iceland across two different months and analyzed for several potentially toxic elements as well as hydrophilic arsenic speciation using HPLC-ICP-MS. Brown macroalgae were additionally sectioned into anatomical parts to determine if the distribution of arsenic species differs throughout the thallus. Select samples were chosen for state-of-the-art lipophilic arsenic speciation using HPLC-ICP-MS/ESI-MS/MS and HPLC-qToF-MS. Limited information is available on arsenic speciation in seaweed thus it is hoped that this extensive profiling of several different species will help elucidate how these unusual compounds are formed and stored. The data from this project will also contribute to the necessary information needed for the risk assessment of arsenic species in seaweed for human consumption and may have an impact on future food safety legislation.

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Peer-reviewed articles

New wave of flavours–On new ways of developing and processing seaweed flavours

Seaweeds have a naturally salty taste owing to their high content of minerals like potassium, besides sodium, which can be used as a healthy sodium replacer in food. In addition, some seaweeds contain a range of potential flavor components which can be released by mild processing and used to naturally enhance the flavor of food. In the present study, flavor ingredients from brown seaweed to use as a food component were developed. The work included enzymatic processing, by subsequently applying an alginase (Alg3) and Umamizyme to freeze dried and milled Ascophyllum nodosum and Saccharina latissima seaweed biomass. The chemical composition was determined by means of monosaccharide, polyphenol, and sodium content. Flavor profiles of the produced flavor extracts were evaluated by e-tongue and a cell assay, as well as by sensory panelists. The seaweed extracts were incorporated into food models and their sodium replacing and flavor enhancing properties were objectively evaluated by trained sensory panelists. The aim was to offer innovative processing solutions and new healthy flavor ingredients to meet salt reduction targets and flavor enhancing properties using seaweed. The results obtained flavor ingredients that are richer in umami and salty taste with the potential to replace sodium and create flavor enhancing ingredients for certain food products.

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Peer-reviewed articles

Aging gracefully? Semi-dry storage as a maturation process to develop the sensory characteristics of the edible red seaweed dulse (Palmaria palmata).

The potential of seaweeds as food is gaining increasing interest among Western consumers. This trend is supported by the nutritional benefits of several species such as Palmaria palmata. Product flavor is a major factor governing consumer acceptance. Developing more attractive flavors in edible seaweeds is a key to sustain the current health food movement based on this resource in Europe. Semi-dry (SD) storage of P. palmata was investigated as a means to increase its sensory quality. SD-samples containing 20% moisture and dried (D) samples (6% moisture) stored up to 126 days were studied. SD-samples stored for a long period (61 and 126 days) developed a distinct sweet, rich, complex flavor and odor as well as a softer texture compared to SD-samples stored for a shorter period (12 days) and D-samples stored for 126 days. Variations in nutritional compounds and physico-chemical properties among samples along with increasing levels and diversity of volatile compounds in SD-samples during storage compared to D-126 suggest that a variety of flavor compounds arise from biochemical reactions involving lipids, proteins and carbohydrates. These reactions are either endogenous or the result of the activity of microorganisms naturally present in the seaweed. They are promoted by a higher moisture content than in dried material (20% vs 6%) and long storage times. These results provide a basis which can be applied to control the storage conditions of seaweeds to produce flavor-rich ingredients attractive to Western consumers.

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Peer-reviewed articles

Data on the sensory characteristics and chemical composition of the edible red seaweed dulse (Palmaria palmata) after dry and semi-dry storage.

The data article refers to the paper “Semi-dry storage as a maturation process for improving the sensory characteristics of the edible red seaweed dulse (Palmaria palmata) ”. The data refers to the analysis of samples of the edible seaweed species Palmaria palmata during storage in a dry (D, containing ca. 6 % moisture) and semi-dry state (SD, containing ca. 20 % moisture). The article includes data from the analysis of samples taken at 0, 12, 61 and 126 days of storage to evaluate the effect of moisture content and storage time on the sensory characteristics of the product. The variations in flavor, odor and texture between samples were measured by sensory evaluation. Data from the analysis of flavor-active compounds (free amino acids and volatile compounds), macronutrient content (soluble proteins and carbohydrates, lipid and mineral fractions), physico-chemical properties (water activity, water and oil-binding capacities, swelling capacity) , color and microbial load are also reported. The information provided in this article can be used by industrial stakeholders (seaweed producers, food industry) to optimize processing and storage conditions of edible seaweeds and by scientists to build upon further knowledge to improve the quality of seaweeds in food applications.

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Reports

Ecological impact on bioactive chemicals in brown seaweeds and their utilization

Published:

01/09/2015

Authors:

Rósa Jónsdóttir, Ásta Heiðrún Pétursdóttir, Halldór Benediktsson, Hilma B. Eiðsdóttir, Karl Gunnarsson, Jóna Freysdóttir

Supported by:

Fisheries Project Fund

Contact

Rósa Jónsdóttir

Research Group Leader

rosa.jonsdottir@matis.is

Ecological impact on bioactive chemicals in brown seaweeds and their utilization

The aim of the project was to investigate the effects of environmental factors on the amount and bioactivity of polyphenols and polysaccharides in seaweed and kelp. The aim was to increase knowledge of the ecology and chemistry of these species for more efficient isolation of biological substances, their further analysis and utilization for bioactivity measurements. Samples of seaweed, marine core, pimples and claw seaweed were taken at three locations in the country; in the northern part of Reykjanes, in Breiðafjörður and Eskifjörður, a total of six times a year, from March to June, in August and October. A method was developed to isolate fucoidan and laminaran polysaccharides from bubble seaweed and claw seaweed. Total polyphenols were measured in all samples but bioactivity in selected samples. In addition, heavy metals and iodine were measured in selected samples. The amount of polyphenols was high in smallpox and seaweed, but low in marine nuclei and gillnets. Antioxidant activity, measured as ORAC and in the cellular system, was high in the samples containing high levels of polyphenols. Seaweed and seaweed showed anti-inflammatory activity. The results of the project significantly increase knowledge in the field of utilization of seaweed and kelp. They are useful in the development of seaweed processing for human consumption that is currently underway.

The aim of the project was to study the effect of environmental factors on polyphenols and polysaccharides in seaweed. Thereby be able to better recognize the ecology and chemistry of these species for more efficient isolation of the biochemical, their further analysis and utilization in bioactive measurements. Samples of Saccharina latissima, Alaria esculenta, Ascophyllum nodosum and Fucus vesiculosus were collected at three different locations, Reykjanes, Breiðafjörður and Eskifjörður, from March to October, in total six times. Method to isolate fucoidan and laminaran polysaccharides was developed. Total polyphenol content (TPC) was measured in all samples and bioactivity in selected samples. In addition, contaminants and iodine were analyzed in selected samples. The TPC was high in F. vesiculosus and A. nodosum but rather low in A. esculenta and S. latissima. The antioxidant acitivty, measured as ORAC value and in cells, was high in samples containing high amount of TPC. F. vesiculosus and A. esculenta had anti-inflammatory properties. The results of the project have increased the knowledge about the utilization of seaweed in Iceland substantially.

Report closed until 31.12.2017

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Reports

New bioactive skin care products

Published:

01/10/2014

Authors:

Hörður G. Kristinsson, Rósa Jónsdóttir

Supported by:

AVS (V 012‐12)

New bioactive skin care products

In recent years, methods have been developed to isolate bioactive substances from seaweed and they have been successfully developed into traditional face creams. The goal of this project was to create a new skin product that contains these new powerful bioactive ingredients with targeted activity against the aging of the skin. The project completed the development of a new product, a powerful eye cream that is specially designed to work on the skin around the eyes and contains bioactive substances made from Icelandic seaweed (Fucus vesiculosus) along with other very powerful and active selected ingredients, eye cream that has have been fairly well received and are considered to have good activity.  

In the past years, new methods to isolate bioactive ingredients from seaweed have been developed and used for cosmetic day cream with good results. In this project a new cosmetic product was developed. This product is a bioactive ultra rich eye cream that is designed and developed to aid in the maintenance of the skin around the eyes. Among its carefully selected and effective constituents are bioactive ingredients, which are extracted from Fucus vesiculosus harvested on the clean shores of Iceland. The product has received good remarks and got positive remarks.

Report closed until 01.11.2016

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Reports

Symposium on seaweed for food February 26th 2011. Summary

Published:

01/06/2011

Authors:

Þóra Valsdóttir, Karl Gunnarsson, Róbert A. Stefánsson, Rósa Jónsdóttir

Supported by:

AVS

Contact

Þóra Valsdóttir

Project Manager

thora.valsdottir@matis.is

Symposium on seaweed for food February 26th 2011. Summary

An open seminar, Forðabúr fjörunnar, was held in Stykkishólmur in February 2011 with the aim of encouraging increased utilization of algae in Iceland, connecting the parties who have been working in this field and coming up with ideas for actions and projects that promote development. in algae processing. The seminar presented the results of recent research in the field of food algae, companies introduced themselves and encouraged discussions about opportunities and strategies in connection with the utilization of food algae off the coast of Iceland. Almost 50 participants attended the seminar and a variety of discussions ensued. The seminar included a proposal for the establishment of an interest group of parties working in the algae industry, which would, among other things, have the role of promoting the acquisition and dissemination of knowledge and experience to and between members.

Symposium on utilization of seaweed for food was held in Stykkishólmur February 26th 2011. The aim of the symposium was to encourage utilization of seaweed in Iceland, give stakeholders opportunity to meet and elicit ideas for actions and projects which can contribute to further development of the seaweed industry in Iceland. At the symposium results from recent research on seaweed and seaweed companies were presented. Opportunities and strategy for improved utilization and value of seaweed were discussed. The first step in establishing Icelandic seaweed consortium was taken.

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Reports

Algae products. Hugmyndir að vörum / Food products from seaweed

Published:

01/06/2011

Authors:

Þóra Valsdóttir, Karl Gunnarsson

Supported by:

AVS

Contact

Þóra Valsdóttir

Project Manager

thora.valsdottir@matis.is

Algae products. Hugmyndir að vörum / Food products from seaweed

Today, the large algae that are used for food in this country are mainly sold dried and processed. There has been little development in their processing and operation to this day. In order to encourage increased utilization and innovation in this field, information was collected on products of large algae on the market in other countries. What particularly hinders the growth of the food algae market here in Iceland and in the neighboring countries is that the tradition for their use has been limited to small and limited social groups. There are therefore many consumers who know little about the use of food algae and more often than not have a negative attitude towards them. The transfer of more traditional vegetable processing methods to algae and mixing in known, general, products such as pasta and rice or in prepared dishes can be a way of introducing food algae to a larger group of consumers.

Today seaweed exploited for food production in Iceland is mainly sold dried and / or cured according to tradition. With the aim to stimulate utilization and innovation in the sector, information was collected on seaweed products in several countries.

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Reports

Gold in the fists of Ægis / Antioxidants from Icelandic marine sources

Published:

01/05/2010

Authors:

Rósa Jónsdóttir, Patricia Hamaguchi, Guðrún Ólafsdóttir, Tao Wang

Supported by:

AVS R&D Fund of Ministry of Fisheries in Iceland

Contact

Rósa Jónsdóttir

Research Group Leader

rosa.jonsdottir@matis.is

Gold in the fists of Ægis / Antioxidants from Icelandic marine sources

The purpose of this project was to screen for anti-corrosive substances from Icelandic seafood such as algae, capelin and sagebrush, to be used as a food additive, target food or as a dietary supplement. Particular attention was paid to the possible use of polyphenols from algae as natural antioxidants to prevent the development of fish products and fish muscle proteins (isolates). This was done by screening for antioxidant activity with several types of antioxidant tests. The most promising antioxidant was chosen to better study its antioxidant properties in food models, i.e. washed cod muscle system, cod protein system and in fish burgers. The results showed, among other things, that polyphenols from the seaweed (Fucus vesiculosus) have high antioxidant properties and are promising for use as a dietary supplement or in food to promote greater stability, taste and nutritional value.

The aim of this project was to explore the natural antioxidant activity of marine sources like seaweed, capelin and cod spleen to use as food additives, functional ingredients or nutritional supplements. The potential application of algal polyphenols as novel natural antioxidants to prevent lipid oxidation of fish muscle and fish protein based products was of special interest. This was done by screening for antioxidant activity using different types of antioxidant assays. The most promising antioxidants were selected and their antioxidant properties studied further in fish model systems and fish patties. The results showed that phlorotannins isolated from bladderwrack (Fucus vesiculosus) had very high antioxidant properties and has a potential as nutritional supplements or food additive to enhance oxidative stability, flavor quality and nutritional value.

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Reports

"Fat is the bait" - bait from fishery byproducts

Published:

01/11/2007

Authors:

Rósa Jónsdóttir, Soffía Vala Tryggvadóttir, Margrét Bragadóttir, Haraldur Einarsson, Höskuldur Björnsson, Sveinbjörn Jónsson

Supported by:

AVS Fisheries Research Fund

Contact

Rósa Jónsdóttir

Research Group Leader

rosa.jonsdottir@matis.is

"Fat is the bait" - bait from fishery byproducts

The aim of the project was to develop and produce composite baits for longline fishing from underutilized raw materials with newly developed snow technology that has been granted a patent. The chemical composition of bait raw material and the use of algae as antidote in bait were examined, in addition to which fishing experiments were carried out. In connection with the project, an application machine was designed and built, and experiments carried out with it in the spring of 2007 ended with 97% application. The use of algae as an antioxidant in bait was not very effective. The bait was quite developed right at the beginning of the storage experiment, so most likely the algae did not work properly. Vitamin C ice cream coating seemed to provide some protection, although vacuum packaging was most important. Many of the experiments that were carried out on the bait aimed to compare the bait with traditional baits made from the same material. Usually, less power was obtained from the bag bait, which can be traced in part to storage, but more problems are needed for storing bag bait than conventional bait. These experiments aim to test whether the bag bait has any repellent effect on fish approaching it. When interpreting the results, however, it must be borne in mind that raw material can be used in bag bait that cannot be used in traditional bait, better utilization of bait raw material is obtained and it is probably best for bag bait to be frozen in the sea. Towards the end of the project, fishing experiments indicated that bag bait yielded similar catches as traditional bait. During the last fishing trip in November 2006, haddock catches were better on bag bait than normal bait, but a flaw in the set-up of the experiment somewhat diminishes the veracity of the result. In addition, vitamin C-fortified bag bait gave slightly more catch than bag bait without vitamin C.

The aim of the project was to develop and produce effective bait for long line fishing from under-utilized raw material using newly developed snow technology that has been patented. The chemical composition of bait raw material and the use of seaweed as an antioxidant in the bait were studied and fishing experiments were done. In connection with the project a baiting machine was designed and produced. Experiments using the machine gave 97% of baited hooks. The use of seaweed as an antioxidant was not successful. The antioxidant activity of the seaweed was probably limited because the bait raw material was already oxidized in the beginning of the storage study. Icing the bait with vitamin C did give some protection although the most important factor seems to be the vacuum packaging. The aim of the fishing experiment was to study the attractiveness of the artificial bait. Most of the fishing experiments were done by studding the artificial bait against the traditional bait using the same raw material. The catch was often less from the artificial bait compared to traditional bait. This can possibly be explained by lower storage stability of the artificial bait due to oxidation. Using artificial bait mainly based on waste from fish processing plants and / or pelagic fish instead of expensive traditional bait material is however promising. The latest fishing experiments showed better results given similar catch for both the artificial and traditional bait. In the last experiment in November 2006 the haddock catch was better for the artificial bait that the traditional bait although it has to be mentioned that the experimental design was incomplete. Artificial bait with vitamin C added gave also better result than the artificial bait without vitamin C.

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