Ascophyllum nodosum contains many valuable compounds, including polyphenols, peptides, and carotenoids that have been shown to exhibit biological activities. These compounds are not a priority ingredient in seaweed meal products for the current users. Hence, the aim of the study was to investigate the chemical and bioactive characteristics of A. nodosum as affected by seasonal variation and evaluate the potential benefits of alternative processing and the utilization of side streams for product development. The analysis of raw materials, press liquid, and press cake from alternative processing and the commercial seaweed meal at different harvesting periods indicated that the chemical composition is linked to the reproductive state of the algae. Phenolic content and ORAC activity increased following the seaweed’s fertile period, making alternative processing more promising in July and October compared to June. Several valuable ingredients were obtained in the press liquid, including polyphenols, which can be used in the development of new high-value bioactive products. The suggested alternative processing does not have a negative effect on the composition and quality of the current seaweed meal products. Hence, the extraction of valuable ingredients from the fresh biomass during the processing of seaweed meal could be a feasible option to increase the value and sustainability of seaweed processing.
Merki: Antioxidant activity
Tengiliður
Rósa Jónsdóttir
Fagstjóri
rosa.jonsdottir@matis.is
Fæðubótarefni úr íslensku þangi / Functional ingredients from Icelandic seaweed
Markmið rannsóknarinnar var að þróa vinnslu á fæðubótarefnum úr íslensku þangi með því að hámarka útdrátt og hreinsunarferil lífefna og mæla lífvirkni þeirra. Bóluþangi var safnað mánaðarlega í eitt ár og efnainnihald og lífvirkni mæld í tilraunaglösum og í frumukerfum. Vinnsla fjölfenóla var sköluð upp og geymsluþol rannsakað. Árstíðabundin sveifla í C‐vítamín innihaldi var mjög skýr og náði hámarki um sumarið. Einnig var mikill munur á magni joðs sem var mun hærra um veturinn samanborið við sýni tekin um sumarið. Andoxunarvirkni fjölfenóla var mjög há, bæði mæld sem ORAC og DPPH og í frumum. Niðurstöður rannsókna í angafrumlíkani benda eindregið til bólguhemjandi áhrifa fjölfenóla úr bóluþangi. Magn fucoxanthins mældist að meðaltali lægst um sumarið en hæst um veturinn þó munurinn væri ekki marktækur. Fucoxanthin úr þangi safnað í janúar og júlí mældist með 90% og 80% andoxunarvirkni í frumum. Niðurstöður þessa verkefnis sýna eindregið að vel kemur til greina að vinna lífvirk efni úr bóluþangi í fæðubótarefni.
The aim of the project was to develop functional ingredients from brown seaweed (Fucus vesiculosus) for use in nutraceutical and functional foods by optimizing extraction of bioactive compounds and characterize their properties to demonstrate possible health benefits. Fucus vesiculosus was collected monthly for one year for chemical characterization and to study bioactivity using in‐vitro chemical and cellular tests. The polyphenol extraction process was scaled up and shelf life of the extract studied. The seasonal variation in vitamin‐C content was clear reaching maximum level during the summer. A large difference was seen in the iodine content which was much higher in the winter compared to the summer. The antioxidant activity of the polyphenols was high, measured as ORAC and DPPH and in cell models. The dendritic cell (DC) model showed indications of anti‐inflammatory effect of polyphenols. The amount of fucoxanthin was on average lowest in the summer but highest in the winter. Cellular antioxidant activity of fucoxanthin samples from January and July was 90% and 80%, respectively. The results of this project indicate that it is feasible to produce functional ingredients from Icelandic seaweed.
Skýrsla lokuð til 01.01.2015