Bioactive compounds in seaweed: functional food applications and legislation

Abstract

Seaweed is more than the wrap that keeps rice together in sushi. Seaweed biomass is already used for a wide range of other products in food, including stabilising agents. Biorefineries with seaweed as feedstock are attracting worldwide interest and include low-volume, high valueadded products and vice versa. Scientific research on bioactive compounds in seaweed usually takes place on just a few species and compounds. This paper reviews worldwide research on bioactive compounds, mainly of nine genera or species of seaweed, which are also available in European temperate Atlantic waters, i.e. Laminaria sp., Fucus sp., Ascophyllum nodosum, Chondrus crispus, Porphyra sp., Ulva sp., Sargassum sp., Gracilaria sp. and Palmaria palmata. In addition, Undaria pinnatifida is included in this review as this is globally one of the most commonly produced, investigated and available species. Fewer examples of other species abundant worldwide have also been included. This review will supply fundamental information for biorefineries in Atlantic Europe using seaweed as feedstock. Preliminary selection of one or several candidate seaweed species will be possible based on the summary tables and previous research described in this review. This applies either to the choice of high valueadded bioactive products to be exploited in an available species or to the choice of seaweed species when a bioactive compound is desired. Data are presented in tables with species, effect and test organism (if present) with examples of uses to enhance comparisons. In addition, scientific experiments performed on seaweed used as animal feed are presented, and EU, US and Japanese legislation on functional foods is reviewed.

Seaweed aquaculture in Norway: recent industrial developments and future perspectives

“…In addition, the market value for seaweed biomass as biofuel is low compared with other product types (Skjermo et al 2014). Seaweed biomass is a rich source of a wide range of bioactive products of potentially high market value (Holdt and Kraan 2011). Relevant applications include (i) human food, (ii) domestic animal and fish feed products, (iii) fertilizer, (iv) prebiotics, (v) cosmetics, (vi) bioactive peptides and (vii) pharmaceuticals and nutraceuticals, and these are predicted to play an important role in the emerging Norwegian bio-economy based on seaweed cultivation (Skjermo et al 2014).…”

“…Moreover, seaweeds contain a large variety of phytochemical constituents that can be used in the prevention and treatment of health diseases by various mechanisms (Holdt and Kraan 2011;Brown et al 2014). Bioactive compounds of interest include polysaccharides (e.g.…”

“…The commercial exploitation of such high value-added products will require relatively low biomass volumes in comparison to bulk products (e.g. biofuels) and is predicted to generate economic value from cultivated macroalgal biomass (Holdt and Kraan 2011;Skjermo et al 2014). However, the extraction of these substances is technology demanding thus, associated with high investment costs.…”

Cultivation of the red algae Kappaphycus alvarezii in Brazil and its pharmacological potential

“…The richness of the algae in minerals, vitamins, bioactive substances, proteins, lipids and polyphenols with antibacterial, antiviral and antifungal properties points to the potential as a supplement in functional foods or as a raw material for the extraction of bioactive compounds (Holdt & Kraan, 2011). Fayaz et al (2005) analyzed K. alvarezii for its chemical composition and found that this species is rich in protein (16.2% w/w), fiber (29.4% w/w) and carbohydrates (27.4% w/w), with a high proportion of unsaturated fatty acids (44.5% of the total; 11.0% oleic acid, 13.5% cisheptadecenoic acid, 2.3% linoleic acid) and saturated fatty acids (37.0%, composed mainly of heptadecanoic acid).…”

“…exhibited reducing power and hydroxyl radical scavenging activity higher than that of standard antioxidants. This antioxidant activity is of particular interest for cosmetic and pharmacological applications (Holdt & Kraan, 2011). Fayaz et al (2005) analyzed the antioxidant activity of extracts of K. alvarezii and observed that the chloroform:methanol (2:1) extract had 82.5% hydroxyl radical scavenging activity, while the acetone extract had 46.04% scavenging activity, both at a concentration of 1000 ppm.…”