News release

From: Griffith University

Seaweed may be a popular food item, but it has certain properties which have the ability to create a shield within the human body, effectively blocking norovirus infection.

To date, there are no approved vaccines or anti-viral treatments for human norovirus, the leading cause of acute gastroenteritis outbreaks worldwide with more than 685 million infections each year.

New collaborative research between Griffith University and Australian biotechnology company Marinova, investigated whether compounds from a range of brown and green seaweeds could block the illness in the early stages of infection.

Senior author Dr Grant Hansman from Griffith’s Institute for Biomedicine and Glycomics said noroviruses infect people by attaching to molecules in the intestine called histo-blood group antigens (HBGAs).

“We tested the seaweed compounds fucoidan and ulvan to see how well they prevented norovirus virus-like particles from binding to human saliva samples which contain HBGAs,” Dr Hansman said.

“Fucoidan, from brown seaweed, showed the strongest and most consistent blocking activity against two major norovirus strains, GII.4 and GII.17.”

The fucoidan likely bound to the HBGA binding pocket to form a physical shield making it harder for the virus to attach.

Co-senior author Associate Professor Thomas Haselhorst said fucoidan had a history of dietary use and had demonstrated good tolerability in human studies, with fucoidan used in premium dietary supplements.

“Our study highlights that fucoidan could be a promising, natural treatment for preventing norovirus infection,” he said.

Research is now focused on validating how fucoidan could be formulated to maximise its protective effect in the gastrointestinal tract.

Norovirus is highly contagious and a leading cause of gastroenteritis which is a disease of the stomach and intestines.

Symptoms can include nausea, vomiting, watery diarrhea, fever, stomach pains, headache, and muscle aches.

The paper ‘Harnessing marine sulphated polysaccharides to inhibit norovirus: from seaweed to solution’ has been published in Microbiology Spectrum.