Seaweeds and their speciality compounds in health and nutrition

Abstract

s / Journal of Nutrition & Intermediary Metabolism 1 (2014) 1e55 7 pseudocereals. The available evidence is largely inferential and based on laboratory studies. Favourable physiological responses have been demonstrated in animals, but randomised controlled trials in humans are few, small in scale and the findings inconsistent. In contrast, elite cereal varieties with enhanced nutritional attributes, such as high-fibre barleys that deliver scientifically substantiated health benefits, are now either on the market or in the development pipeline. Importantly, these nutritional traits are expressed in high yielding modern cultivars. The resultant products show great promise in meeting growing consumer demand for healthier, affordable grain-based foods. As wholegrains, pseudocereals are nutrient-dense foods that provide more options for consumers seeking to improve the nutritional quality and variety of their diets, especially individuals on a gluten-free diet. However, further research is required to elucidate and substantiate the health benefits of pseudocereals. Funding source(s): N/A. SEAWEEDS AND THEIR SPECIALITY COMPOUNDS IN HEALTH AND NUTRITION J.H. Fitton . Marinova Pty Ltd, Hobart, Tasmania, Australia E-mail: helen.fitton@marinova.com.au Seaweeds, or marine macroalgae have long been a part of the human diet (1). Coastal harvesting and transport of macroalgae inland for food use still occurs today in South America. In this way, inland populations avoid iodine deficiency and enjoy sea vegetables in their diet. Marine macroalgae have also been used as medicines by ancient civilizations such as those at Monte Verde in Chile, a site that dates back an astonishing 12,000 years (2). Marine macroalgae are a rich source of colloids that are used in foods and pharmaceuticals. The main commercial ‘phycocolloids’ are agar, alginate and carrageenan, familiar as thickening agents in foods. Aside from these colloids, there is a remarkable array of bioactives in current use or devel- opment. These include carbohydrate compounds such as b-glucan and fucoidan, in addition to pigments like fucoxanthin and polyphenols (3). Marinova is an Australian manufacturer of fucoidan. Fucoidan is a non- gelling sulfated fucose rich polysaccharide found only in brown macro- algae. It is non-toxic, yet displays marked bioactivity as an anti-viral, anti- bacterial, anti-inflammatory and immunomodulatory compound. Several new studies point to potential as an adjunct to cancer therapies (4). Historically, fucoidanwas used as a selectin blocking agent. Selectins are cell surface receptors on white blood cells that perform a ‘braking function’ for the cells, allowing them to roll on an organs endothelial surface and ulti- mately enter that tissue space. Fucoidan inhibits ‘P’ and ‘L’ selectins and thus leukocyte adhesion and rolling thereby reducing inflammation in tissues. A new animal health product demonstrates this direct anti-inflammatory activity. Thoroughbred horses are at risk of gastric ulceration during periods away from a natural grazing environment and oral fucoidan has a calmative effect and reduces the need for pharmaceutical intervention. The anti-viral activity of fucoidan is caused by receptor blocking activity, rather than a virucidal action. Fucoid an prevents the entry of viruses to cells, thereby preventing viral replication. Fucoidan from Undaria pinna- tifida (commonly known as wakame), is a highly effective inhibitor of clinical strains of herpes viruses, including those resistant to acyclovir (4). A similar level of inhibitory activity is seen in strains of influenza viruses demonstrating fucoidan has excellent potential as an anti-viral agent. Fucoidan also inhibits the adhesion of the stomach ulcer causative agent Helicobacter pylori. In recent studies, fucoidan compounds were demon- strated to significantly reduce adhesion to gastric cells in vitro. There is a need for novel approaches to treating Helicobacter pylori infection as resistance to current antibiotics increases. Fucoidan compounds offer a new strategy as adjunct therapies. Fucoidan stimulates both innate and specific immunity and can be ther- apeutically useful. Immunomodulation by fucoidan has been reported by a number of research groups. For example, in a double blind placebo controlled trial, fucoidan increased the immune response to seasonal vaccination in an elderly population (5). Lastly, a co-extracted fucoidan containing a large concentration of poly- phenol has been developed by Marinova. This has a remarkable level of antioxidant activity directed against the superoxide anion the main precursor of free radicals. This free radical neutralising activity together with the anti-inflammatory nature of fucoidan makes the extract thera- peutically appealing. In a clinical trial with topical application of this extract, there were significant inhibitory effects of UV damage, in addition to significant reductions in age related pigmentation. To conclude, whole seaweeds, and specialty compounds derived from seaweeds have great value in foods, supplements, pharmaceuticals and animal health applications. Future research into these compounds holds great promise for novel products. Funding source(s): Marinova Pty Ltd.