The team from the University of Queensland are working with two industry partners – Qponics and Nutrition Care – and have received financial backing from the government. The two-year €1.42m (A$2.1m) research project officially starts in early October, but the team has made headway on cultivation and extraction methods.
Oil with 40% EPA
Speaking to NutraIngredients, lead scientist Dr Peer Schenk said the team had successfully cultivated a native microalgae high in omega-3 on the university’s one-hectare research farm in Queensland.
“We tried breeding but that was unsuccessful and we tried mutation and that was also unsuccessful. Basically, what we’ve done is looked at what is out there in nature, and the next part is metabolic engineering.”
He said the team had used external stimuli to induce production of lipids in Nannochloropsis sp. as well as trigger higher levels of EPA (eicosapentaenoic acid). Starving the algae of nutrients triggered lipid production, he explained, and short exposure to UV-light increased EPA levels.
“We’ve developed algae strains that are very high in omega-3: 40% of the oil is EPA, which is similar to fish oils, well, it’s actually higher than fish oils… This 40% EPA level is similar to triple concentrated fish oil.”
The high EPA level in Nannochloropsis sp. has previously been documented by Australian researchers from James Cook University. In their research, last year, microalgae species were compared and Nannochloropsis sp., came out well and showed commercial potential as a nutrient.
Dr Schenk wants to optimise its solvent-free extraction method to achieve a more financially viable product.
“The normal method is to use hexane as a solvent, but we are looking at a previous extraction before that – a bit like cold extraction in olive oils.” Using water to break up the cells and then filter out the oil, he said the team could achieve extraction at an earlier stage.
“But we’re still optimising this; it’s not perfect yet,” he added. “We have to see how scalable our process is, because it’s all based on cost.”
Market promise on a large scale
Dr Schenk said algae-derived omega-3 oils were gaining prominence as concerns mounted about fishery sustainability and animal-based diets.
“If you grow algae on land, you can provide a vegetarian product and something that is sustainably sourced – it can be produced almost in any quantity because we can do it on land; we don’t have to deplete our fish stocks.”
Certain Asian markets offered potential for different reasons.
“India has a high population of vegetarians, so it would be an attractive product to them, and China are already very health conscious and know algae is a product they like. So, having an algae-derived omega-3 would go quite well in that market.”
Dr Schenk said the project sought to reduce waste to zero. “The idea is to produce this rich oil from the algae, extract the omega-3 and then use the remaining biomass for other purposes.”
The biomass after extraction is extremely high in protein – which could be interesting in food and feed – but also rich in a number of carotenoids to potentially extract; one being lutein. The added benefit from a cost standpoint, he said, was that the biomass could also replace the need for fertilisers.
“Nutrient recycling is a new concept we are looking at. We’re extracting the oil and after that we’re putting the biomass into an anaerobic digester – a closed container that produces biogas – and we then burn it or can use it for electricity. But then the added benefit is that the nutrients get freed up from the remaining biomass and this liquor is high in nutrients and can be used to grow more algae,” he explained.
“In a way, we’re closing the loop; we’re closing the cycle of the nutrients.”
He said the team, so far, had succeeded in recycling 70% of the algae’s nutrients but would aim to achieve 100% in the next two years.
“So far, we haven’t really analysed it a lot but we’ve demonstrated it on a midscale. But, we’re not happy yet with the 70% - we’d like to go higher and this needs to be done under the project.”