Enzyme-made seaweed compounds show much prebiotic and nutraceutical potential
Researchers point to the enzyme-assisted extraction and hydrolysis of macromolecules as pivotal in enhancing compound properties that include prebiotic, antioxidant and anti-inflammatory effects.
“Advanced enzymatic processing is a key trend for the efficient extraction and digestion of value-added bioactive compounds from seaweeds,” said the team, led by Dr Wei Zhang, professor of medical biotechnology at Flinders University in Australia.
“The potential of these compounds for a number of functional food applications is being increasingly recognised, particularly with regard to prebiotic supplements.”
Interest in prebiotics as functional foods has helped the global prebiotics market swell to over €2.5 bn ($2.9 bn) in 2015 as rising consumer awareness of gut health issues, backed up by compelling research, continues to accelerate.
Prebiotic food products and supplements manufacturers Roquette, Abbott Nutrition, and FrieslandCampina are just a handful of companies currently jostling for market position.
Another player, Beneo have made much headway with its inulin and oligofructose food ingredients made from chicory.
Its food ingredients have found their way into consumer products in the food & beverage, functional foods & dietary supplements and confectionary.
In 2016, Beneo and Belgian sugar producer Raffinerie Tirlemontoise agreed to invest €4.6 million in R&D at its Belgian laboratory facility, with a focus on analytical and microbiological research.
Seaweed as a functional food
Consumer interest is also fuelling demand for new functional foods that can contribute to health-promotion or disease prevention, beyond providing basic nutrition.
Much commercial product development and patent activities on seaweed-derived bioactive compounds are concentrated in the Far East, where the food is a popular staple food in the region.
Japanese company Takara Shuzo and Biolsystems Company from Korea have patented the isolation of oligosaccharides from red seaweeds such as Gelidium, Pteocladia, and Hypnea that claim to have benefits in addressing diabetes and rheumatism.
The Riken Vitamin company based in Tokyo, has developed Wakame jelly containing peptides extracted from brown seaweed Undaria pinnatifida that claim to have antihypertensive activity.
Antioxidant components comprising phlorotannin from brown seaweed Ascophyllum nodosum are patented for use as functional ingredients in food formulations.
Closer to home, Seaweed & Co – which sources its wild Ascophyllum seaweed from the Scottish Hebrides islands, sells this ingredient via food supplement channels for salt replacement and nutritional enhancement with EU-approved, iodine-based health claims.
EU seaweed regulation
According to Dr Zhang’s review, seaweed use in food and functional food supplements has found a mixed consensus amongst the relevant EU regulatory authorities.
In France, 21 species of macroalgae, including brown seaweeds (Ascophyllum nodosum, Undaria pinnatifida, Laminaria japonica, etc.), red seaweeds (Palmaria palmata, Porphyra umbilicalis, Gracilaria verrucosa, etc.), and green seaweeds (Ulva and Enteromorpha species), are authorized as vegetables and condiments for food consumption.
Belgium's report from the Superior Health Council recommended the consumption of Hizikia fusiforme was of concern due to high levels of inorganic arsenic, and the consumption of other seaweeds should be limited to 7 g dried material per day.
While Norway's National Institute of Nutrition and Seafood Research (NIFES) suggested that high levels of inorganic arsenic and cadmium were found in Norwegian brown seaweeds, a low risk of food safety hazards was observed.
Despite the opportunities, the research team were wary of the challenges that remained in improving enzyme techniques in terms of its productivity and profitability.
“Enzyme intensification using other physical inputs, and enzymes with activities specific to seaweed structures, should be further investigated,” they recommended.
“Furthermore, the scaled up industrial process should be designed to support commercial implementation.
The adherence of products to safety legislation are also critical and complex subjects requiring attention in order to push forward with the commercial development of seaweed ingredients for functional food and nutraceutical products.
Source: Trends in Food Science & Technology
Published online ahead of print: doi.org/10.1016/j.tifs.2017.10.002
“The development of seaweed-derived bioactive compounds for use as prebiotics and nutraceuticals using enzyme technologies.”
Authors: Wei Zhang et al.