Phlorotannins and macroalgal polyphenols: Potential as functional food ingredients and role in health promotion

Marine macroalgae are rapidly gaining recognition as a source of functional ingredients that can be used to promote health and prevent disease. There is accumulating evidence from in vitro studies, animal models, and emerging evidence in human trials that phlorotannins, a class of polyphenol that are unique to marine macroalgae, have anti-hyperglycaemic and anti-hyperlipidaemic effects. The ability of phlorotannins to mediate hyperglycaemia and hyperlipidaemia makes them attractive candidates for the development of functional food products to reduce the risk of cardiovascular diseases and type 2 diabetes. This chapter gives an overview of the sources and structure of phlorotannins, as well as how they are identified and quantified in marine algae. This chapter will discuss the dietary intake of macroalgal polyphenols and the current evidence regarding their anti-hyperglycaemic and anti-hyperlipidaemic actions in vitro and in vivo. Lastly, this chapter will examine the potential of marine algae and their polyphenols to be produced into functional food products through investigating safe levels of polyphenol consumption, processing techniques, the benefits of farming marine algae, and the commercial potential of marine functional products.