Marine macroalgae as sources of protein and bioactive compounds in feed for monogastric animals

Abstract

Marine macroalgae are considered as promising sustainable alternatives to conventional terrestrial animal feed resources. The advantages include high growth rate, potential cultivation in saltwater, and no occupation of arable land. Macroalgae are broadly classified as brown (Phaeophyta), red (Rhodophyta) and green (Chlorophyta) algae, and are a diverse group of marine organisms. The nutritional value of macroalgae is highly variable. The protein and essential amino acid content can be low, especially in brown species, and indigestible polysaccharides adversely affect the energy value. Optimal use of macroalgae in feeds requires suitable processing, and biorefinery approaches may increase protein content and improve nutrient availability. Macroalgae are rich in unique bioactive components and there is a growing interest in the potentially beneficial health effects of compounds such as laminarin and fucoidan in different macroalgal and macroalgal products. This review summarizes current literature on different aspects of the use of macroalgae as sources of protein and health-promoting bioactive compounds in feed for monogastric animal species.

Phenolic, flavonoid, and amino acid compositions reveal that selected tropical seaweeds have the potential to be functional food ingredients

“…Seaweeds are considered a good source of protein, as they contain all essential amino acids, acidic amino acids, and conditional essential amino acids (Tanna & Mishra, ). Amino acid profiling of selected seaweeds confirmed that they contain higher concentration of some essential amino acids than the milk and egg protein consumed worldwide (Øverland, Mydland, & Skrede, ). There are numerous reports on the amino acid composition of seaweed species from various locations.…”

Seaweeds in Pig Nutrition

“…A major component of brown seaweed cell walls is a salt form of alginic acid, alginate with the content ranging from 140-400 g/kg DM [30]. Brown seaweed walls are also rich in fucoidans, which are saccharide units with different degrees of sulphation.…”

“…Diatoms structural characteristics, and thus the different types of functional components have various biological applications. The fucoidan content varies in relation to seaweed species and season, although the content ranges from 20 to 200 g/kg DM, with the highest value in Fucus vesiculosus [17,30,31]. Laminarin, composed of (1,3)-b-D-glucopyranose residues, is the main reserve carbohydrate of brown seaweeds with a content ranging from 0 to 300 g/kg DM.…”

“…and Saccharina latissima a high content of laminarin has been reported, while, Ascophyllum nodosum and, Fucus spp. presented a low laminarin content [17,30,31]. Laminarin presents prebiotic, immunomodulator and antioxidant activities [32].…”

“…The total polysaccharide content (% DM) is 29-67% in green algae (Chlorophyta), 10-59% in red algae (Rhodophita) and 10-75% in brown algae (Phaecophyta). [29].A major component of brown seaweed cell walls is a salt form of alginic acid, alginate with the content ranging from 140-400 g/kg DM [30]. Brown seaweed walls are also rich in fucoidans, which are saccharide units with different degrees of sulphation.…”