The marine organism is being tested in myriad ways to provide an agricultural alternative that benefits the environment, our health, and removes pollution from waterways.
On a summer’s morning in 2019, in the small New South Wales farming community of Bolong, on the Shoalhaven River, Dr Pia Winberg walked into the processing plant from which she was building her budding seaweed business.
Winberg had overnight left a tank of liquid to filter. It contained an extract of a native species of Aussie seaweed — with the sci-fi-esque name of “Species 84.”
She was emptying a vat of the concentrated gel, with her hair tied back, a cap on, and eye protection in place just like any other day at the plant. It’s there her memory stops.
The next thing Winberg remembers is crouching down on the floor with her long brown hair stuck fast somewhere above her.
“All I felt was a frustration,” Winberg says. “A bit like when your hairbrush is tangled, you don’t know whether to turn it left or right to untangle. Then I just sort of sighed and looked down at my hands and thought, ‘why are they red?’”
In fact, in a freak accident that would prove a practical need for her own budding research on the healing properties of algal gels, Winberg had been scalped.
She doesn’t remember the rest of the day’s events, but witnesses say she pulled her own scalp from the machine, walked to the facility’s small office, and calmly asked the people inside to call for an ambulance.
“Then they followed me down the hall and I went and sat in my office chair with my scalp in hand,” she says.
It’s a gruesome story, but Winberg is disarmingly upbeat about it.
“It was just a very freaky accident,” she says. “But it gave me insight into what surgeons face, because, as an academic, you sit there looking at the theory of ‘this molecule does what with this’, but what does the clinician actually face?”
These considerations were important for Winberg, because the gel that she had been extracting was, ironically, undergoing early-stage testing as a balm for healing wounds and burns, part of the ever-expanding pharmacopoeia of seaweed-based health products she was developing under her brand, PhycoHealth.
The extract came from a unique species of Australian green seaweed she had discovered herself, and which she was now growing in vast pools of water that were being fed with the excess nutrients embedded in the run-off from a wheat refinery – including phosphates, nitrogen, and carbon.
Winberg’s unusual algal journey began several decades earlier, while she was researching for her masters in marine systems ecology. Back then, she was in Sri Lanka, investigating the negative impacts of tiger-prawn farming.
“They were just spewing out the wastewater into the local coastal environment,” she says.
Organic waste streams, produced by industries ranging from fish farms to grain refineries, have a deeply underestimated impact on the planet. Though the nutrients contained within are harmless in the right quantities, an overload of any single nutrient can upset the delicate balance of an aquatic ecosystem, in a process known as “eutrophication.”
“As an academic, you sit there looking at the theory of ‘this molecule does what with this’, but what does the clinician actually face?”Dr Pia Winberg
“The nutrients cause excessive growth of microscopic algae in the water,” explains Professor Martina Doblin, a marine scientist who heads up the Productive Coasts program at the University of Technology Sydney.
“This leads to two things: first, large fluctuations in dissolved oxygen in the water – typically very low oxygen at night when the algae respire – which can cause fish kills.
“Secondly, the algae in the water reduces the light that penetrates to deeper depths, which can limit the growth of benthic plants [plants attached to the sea or river floor].”
The negative impacts of algal blooms don’t end there. Once the offending algae die and sink to the bottom, they create thick mats of dead organic matter on the seafloor which rot, using up oxygen and creating hostile, hypoxic zones.
The death of one such massive algal bloom was found to be behind the catastrophic mass fish kills that occurred along a 40-kilometre stretch of the Darling River in 2019, in that case because low water levels diminished water quality, allowing microscopic algae to thrive.
“There’s now a belt around the world of global anoxic dead zones,” says Winberg. “They’re all outside cities, and they impact fisheries, health, food.”
Eutrophication from agriculture is estimated to cost Australia more than $200 million every year, and algal blooms in freshwaters alone cost between $180 and $240 million a year. Some parts of Australia are particularly susceptible, like the sandy soils of southwestern Australia, which struggle to capture and retain nutrients that flow through them.
Within this mess, though, Winberg sees potential.
“These nitrogen loads are also so wasteful, because these are nutrients that can be recycled to offset the negative fossil fuel impacts of fertilisers,” she says. “So, the coastal zones and all of our waste streams globally are such an underestimated impact, but also an underestimated resource opportunity, for both energy and food. Waste is the key to that circular economy.”
For several decades, Winberg applied academia to the problem, developing models for fish farms with seaweed – a natural nutrient filter – built into the system.
“But I realised after a while, as an academic, that people don’t pay to clean up,” she says. The solution, she reasoned, was to start a food business using seaweed, fed with nutrients from wastewater, as its base.
Seaweed: a health and beauty wunderkind?
Seaweed has been touted as a health-food wunderkind, often promoted with overzealous claims based on limited evidence. But Winberg says some of these health claims are based in fact, and she’s doing the hard yards to prove it.
Moving back from Sri Lanka, Winberg settled on the New South Wales South Coast, and saw the fundamental disconnect between marine conservation and local industries like fishing and grain refining.
“There should be a food production system from the marine environment in the middle that serves both environmental management and circular economies, as well as livelihoods.”Dr Pia Winberg
“There should be a food production system from the marine environment in the middle that serves both environmental management and circular economies, as well as livelihoods.”
Now, her seaweed is grown in vast tanks fed by wastewater from Australia’s largest wheat refinery Manildra, in Bomaderry, New South Wales.
The seaweed she grows is turned into supplements as well as combined into various food products, like pasta and muesli.
“Seaweed is the king of fibre, because unlike plants it’s got very diverse types of fibre,” she says, “without all of the cellulose and lignins and resistant fibres that you get in land plants, because they have to resist gravity.”
The average Australian consumes about twenty grams of fibre per day, and the minimum recommended is 35 grams. Winberg thinks seaweed could bridge the gap in low-fibre Aussie diets, as well as battling health issues like high cholesterol and inflammation.
Winberg and colleagues have run a set of early stage clinical studies with a supplement containing gel extracted from Species 84, the results of which are published in the Journal of Marine Drugs.
The study found that the polysaccharide they’ve named xylorhamnoglucuronan, a key component of the gel, reduced inflammatory markers and cholesterol in 64 participants when consumed daily as a supplement.
Seaweed is also rich in other minerals and trace elements which people often find themselves deficient in, including B12, iron and iodine.
There’s room for caution, though: speaking with Time Magazine, Nancy Oliveira, a senior nutritionist at Brigham and Women’s Faulkner Hospital in Massachusetts, cautioned that excess seaweed consumption can pose several risks to health.
Excess iodine, for example, can cause problems for people with thyroid disorders, while vitamin K, which seaweed is high in, can interact poorly with blood thinners, and potassium, in high amounts, can be dangerous for people with heart and kidney conditions.
A 2017 review of the potential for a local seaweed industry in Australia found a lack of best practice standards for nutrition and quality assurance were the biggest single barrier to growth of the sector, though Australia does monitor imported seaweeds for levels of arsenic and iodine.
Winberg and colleagues had also been looking into the gel’s potential as a topical treatment for wound healing, long before her own accident facilitated a need for it. Alginate gels, usually extracted from brown kelp, have long been known to speed wound healing, keeping tissue moist and soothing pain. Winberg reasoned that a similar benefit might come from her seaweed gel.
Working with Professor Gordon Wallace, Director of Intelligent Polymer Research at the University of Wollongong, Winberg discovered that the gel extracted from Species 84 had deeply unusual properties.
“We found that the design of our seaweed gel was distinct from brown and red seaweeds,” she says. “Instead of being close to other seaweeds, it was closer to the connective tissue in mammals.
“So, when we printed bio-inks with skin cells in the lab, we saw that the skin cells were patching to it, and started to lay down guide strings of elastin and collagen.”
During the weeks and months of her recovery, over a gruelling series of reconstructive surgeries that stretched the remaining skin on her scalp , Winberg applied her seaweed extract, which she’d already made into a moisturiser.
She suspects the speed of her recovery and minimal scarring is in part down to regular use of the gel, though her hair hasn’t fully grown back. Nowadays, she dons glamorous handkerchiefs over her hair.
Though her faith in the gel’s wound healing properties is at this stage based mainly on her own personal experience, promising initial studies suggest the extract can help wounds heal properly – but Winberg says more research needs to be done.
“We want to know, how does that work? Where does the scar formation stop and how might we prevent scar formation?
“That’s the mission we’re on now. We’re not putting that on people today, but hopefully it won’t take too long with the projects we’re underway with.”
Is seaweed the key to a circular economy?
For Winberg, the health benefits of seaweed are exciting, but they’re merely a conduit for her real passions: marine conservation and sustainability.
Agricultural run-off is one of the biggest problems facing marine environments around Australia, as fertilisers, which are also resource intensive to make, seep into local rivers and eventually the ocean.
Agriculture also contributes to around 13% of Australia’s carbon footprint, uses up about 60% of the water available for human use, and occupies vast swathes of land – some of which, if managed well, could be used to capture and sequester carbon.
“We are producing a food that doesn’t use freshwater, and we’re offsetting the need to make fertiliser for that food because we’re capturing nutrients.”Dr Pia Winberg
At the same time, agriculture is a necessary component of Australia’s economy and food security. But Winberg believes that by building a thriving seaweed sector, replacing in part broad acre farming, Australia could grow some of its food in a less resource intensive way that produces minimal waste and cleans up wastewater from other industries.
“We are producing a food that doesn’t use freshwater, and we’re offsetting the need to make fertiliser for that food because we’re capturing nutrients,” she says.
“If you replaced 10% of the wheat industry, that’s a million hectares of land,” she says. “And that’s huge in terms of the amount of fossil fuels, fertiliser and water and everything else that goes into it.
“Our seaweed grows fifty times faster in a given area than you could grow a land crop. So, if we have a one hectare farm, which is what we’re trying to build as we speak, we can produce 100 tonnes of dried seaweed with no roots, shoots or waste products.
“That’s 100 tonnes of a food product, whereas if you were looking at a traditional crop on land, you’d be between two to five tonnes of feed in a hectare. So, it’s saving land use, water use, and coastal pollution.”
Amalyah Hart has a BA (Hons) in Archaeology and Anthropology from the University of Oxford and an MA in Journalism from the University of Melbourne.