Prebiotics from marine macroalgae for human and animal health applications

Abstract

The marine environment is an untapped source of bioactive compounds. Specifically, marine macroalgae (seaweeds) are rich in polysaccharides that could potentially be exploited as prebiotic functional ingredients for both human and animal health applications. Prebiotics are non-digestible, selectively fermented compounds that stimulate the growth and/or activity of beneficial gut microbiota which, in turn, confer health benefits on the host. This review will introduce the concept and potential applications of prebiotics, followed by an outline of the chemistry of seaweed polysaccharides. Their potential for use as prebiotics for both humans and animals will be highlighted by reviewing data from both in vitro and in vivo studies conducted to date.

Keywords: human and animal health; marine macroalgae; polysaccharides; prebiotics.

Figure 1

Distribution of the dominant, sub-dominant and minor components of human fecal microflora. Major dominant phyla are denoted. *: Other components are at the family or genus level (adapted from reference [16]).

Figure 2

Mode of action of prebiotics and purported health benefits in humans and animals.

Figure 3

Green seaweed constituents: (a) α-L-rhamnose and (b) glucuronic acid [31].

Figure 4

Constituent acids of alginic acid, where (a) is β-D-mannuronic acid and (b) is α-L-guluronic acid [43].

Figure 5

Fucoidan: Branched polysaccharide sulfate ester with L-fucose building blocks as the major component with predominantly α-(1,2) linkages [43].

Figure 6

Basic chemical units of laminarin, made up of β-(1,3) and β-(1,6) linked glucose.

Figure 7

Agar constituents [31] (R=H or CH₃).

Figure 8

Basic structure of kappa-, iota-, and lambda-carrageenan [60].