Reports

Seaweed supplementation to mitigate methane (CH4) emissions by cattle

Published:

27/09/2021

Authors:

Dr. Ásta H. Pétursdóttir (Matís), Dr. Helga Gunnlaugsdóttir (Matís), Natasa Desnica (Matís), Aðalheiður Ólafsdóttir (Matís), Susanne Kuenzel (University of Hohenheim), Dr. Markus Rodehutscord (University of Hohenheim), Dr. Chris Reynolds (University of Reading), Dr. David Humphries (University of Reading), James Draper (ABP).

Supported by:

EIT Food

contact

Ásta Heiðrún E. Pétursdóttir

Head of Public Health and Food Safety

asta.h.petursdottir@matis.is

SeaCH4NGE results include a detailed analysis of the chemical composition of seaweed, including heavy metals and nutritional composition. Iodine concentration proved to be the main limiting factor regarding seaweed as a feed supplement. The decrease in methane observed in laboratory methane production experiments (in vitro) is likely due to compounds called fluorotannin rather than bromoform, a known substance that can reduce methane production in ruminants. In vitro screening of the seaweed showed a moderate decrease in methane, but lower methane production was dependent on seaweed species. The reduction was dose-dependent, ie by using more algae, a greater methane reduction could be seen in vitro. The same two types of seaweed were used in the Rusitec experiment (in vitro), which is a very comprehensive analysis that provides further information. An in-vivo study in cows showed that feeding cattle with a mixture of brown algae has a relatively small effect on methane emissions. However, fluorotannins are known to have other beneficial effects when consumed by ruminants. The report also includes a survey of British cow farmers' attitudes towards algae feeding and climate change.

Skýrslan er lokuð / This report is closed

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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

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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