The aim of the project was to investigate the effect of environmental factors on the amount and bioactivity of polyphenols and polysaccharides in seaweed and kelp. In this way, the aim was to increase knowledge of the ecology and chemistry of these species for a more cost-effective isolation of biological substances, their detailed analysis and utilization for bioactivity measurements. Samples of kelp, kelp, bubble seaweed and claw seaweed were taken in three places in the country; on the north side of Reykjanes, in Breiðafirður and Eskifjörður, a total of six times during the year, from March to June, in August and October. A method was developed to isolate fucoidan and laminaran polysaccharides from bubble seaweed and kelp. Total polyphenols were measured in all samples and bioactivity in selected samples. In addition, heavy metals and iodine were measured in selected samples.
The amount of polyphenols was measured high in bubble seaweed and claw seaweed, but low in marin core and kelp. Antioxidant activity, measured as ORAC and in cellular systems, was high in the samples containing high levels of polyphenols. Sea kelp and seaweed extract showed anti-inflammatory activity.
The results of the project significantly increase knowledge in the field of seaweed and kelp utilization. They are useful in the current development of seaweed processing for human consumption.