Canola researchers in omega-3 breakthrough

New canola varieties being developed in Australia look capable of producing the highly coveted, high-value long-chain omega-3 oil

Key points

  • Australian growers to be the first to benefit from research into the terrestrial production of long-chain omega-3 oils
  • The research is a collaboration between the GRDC, CSIRO and Nuseed
  • Field trials of the new canola lines are due to begin this year

Australia has taken the lead in the development of new GM canola lines that produce long-chain (LC) omega-3 oils.

These are the oils in increasing demand for their human health properties and as a feed additive in the world’s rapidly growing fish-farming industries.

The Australian research has effectively succeeded in extending canola’s existing short form of omega-3 (alpha-linolenic acid, or ALA) into the LC varieties – eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) – that are normally sourced, via fish, from marine plants.

It is a significant scientific development that has the potential to shift the sourcing of these important omega-3 health oils from marine plants to a terrestrial crop. This is expected to ease the heavy worldwide pressure on fish stocks.

“These glasshouse trials are now ready to move to field trials, to test the technology under field conditions, and begin the process of selecting the best combination of agronomic performance and DHA oil levels.”

– Dr Surinder Singh 
Photo of man inspecting canola

Dr Surinder Singh from CSIRO Plant Industry with GM canola being used in omega-3 experiments.

PHOTO: Brad Collis

The research has been a collaboration between the GRDC, CSIRO and Nuseed. At CSIRO, the project is being led by Dr Surinder Singh and coordinated by Dr James Petrie.

Dr Petrie credits a large part of the team’s world-leading position to a CSIRO research ethos that has been very end-point focused. This encouraged an acceleration of the development phase by using a method that allows many gene combinations (for oil production) to be tested more efficiently.

“We have been able to determine much more rapidly than our competitors how to put together all the genes we need into a single combination,” Dr Petrie says.

Dr Singh says that in glasshouse trials over three seasons – a comparatively short timeframe – the germplasm developed at CSIRO achieved levels of DHA in the canola oil comparable to levels found in bulk fish oil.

“These glasshouse trials are now ready to move to field trials, to test the technology under field conditions, and begin the process of selecting the best combination of agronomic performance and DHA oil levels,” Dr Singh says.

Nuseed will manage the field trials and subsequent commercialisation, and if the project is successful will bring LC omega-3 canola varieties to market.

Photo of Dr Malcolm Devine

Dr Malcolm Devine, from Nuseed.

Dr Malcolm Devine at Nuseed says the project’s ultimate goal is to make Australia the first and foremost global supplier of DHA-containing canola oil, therefore creating valuable new markets for Australian growers.

“Post-farmgate, we intend the grain to be processed into oil in Australia, targeting a number of potential markets. These could include dietary supplements, pharmaceuticals and DHA-rich aquafeed markets,” Dr Devine says.

However, as successful as the research has been to this point, he says commercialisation is still several years away: “We have seen some very interesting and positive results so far, and taking the material into the field is the next step.”

The field trials have been approved by the Office of the Gene Technology Regulator. The trials will allow the canola to be evaluated for agronomic performance, LC omega-3 content and genetic stability under field conditions – all important factors in achieving commercialisation.

While being aware that GM food crops can be controversial with the public, the project partners all say that few feasible alternative supply options exist for this particular nutrient and there is a compelling need for a sustainable source given EPA and DHA’s health benefits.

Unlike previously released GM canola varieties, the DHA trait is an example of an ‘output trait’, meaning it is designed to provide benefits to consumers. This differs to existing ‘input traits’ that provide agronomic benefit to growers.

While uptake of input traits – primarily herbicide and pest resistance – has become commonplace, GM output traits globally are still finding their way through the R&D pipeline.

Photo of Dr James Petrie

Dr James Petrie in a glasshouse with flowering canola

“I think the sustainability and environmental credentials of the crop are significant factors supporting the use of GM technology in this particular application,” Dr Petrie says.

“When you do the calculations, if you can achieve 12 per cent levels of DHA in the canola oil, then one hectare of this crop can meet the same production levels produced by 10,000 ocean fish. And we couldn’t have achieved this using conventional plant breeding methods.”

Dr Ron Osmond, the GRDC’s manager for commercial technology delivery, says the GM canola system is already well established in Australia. “It has worked quite well so far. So the same principles around high-quality stewardship and identity preservation would be expected for the DHA-producing canola when it is commercialised.”

Overall, Dr Osmond and Dr Devine say that the potential for commercialisation is strong and the science developed by CSIRO is robust and thorough.

“Technically and scientifically it has been a world-class achievement,” Dr Osmond says. “I think it’s a great example of public sector and private sector working together towards a new technology with a profitable outcome for Australian growers.”

Overview of omega-3 oils

Polyunsaturated omega-3 family

Unlike saturated fatty acids that are metabolised by humans to provide energy, heat and calories, the polyunsaturated omega-3 family is essential for important biological functions.

They are especially vital for the brain, sense organs (such as the retina), adrenal glands and testes, where they are used to construct membranes, create electrical potentials and move electrical currents.

They can also be converted into hormone-like substances such as prostaglandins that regulate cellular activities on a moment-to-moment basis. For instance, some prostaglandins keep blood platelets from sticking together and thereby help prevent heart attacks and strokes caused by blood clots in our arteries.

Important omega-3 oils include:

  • alpha-linolenic acid (ALA) – found in land plants, including flax, hemp seed, canola, soybeans, walnuts and dark-green leaves;
  • stearidonic acid (SDA) – found in blackcurrant seeds and uncommercialised wild seeds; and
  • eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) – made by marine algae but accumulate in marine food chains. Farmed fish such as salmon, trout and mackerel are excellent sources of long-chain omega-3. Among land animals, sources are the brain, eyeballs, adrenal glands and testes.

Some differences between terrestrial and marine omega-3 oil

The terrestrial short-chain alpha-linolenic acid (ALA) is typically sourced in the diet from oils and seeds from plants such as canola, soybeans, flaxseed and walnuts.
If sufficient quantities of ALA are not eaten then a ‘deficiency syndrome’ can arise. Common symptoms include eczema-like skin eruptions, loss of hair, liver and kidney degeneration, behavioural disturbances and susceptibility to infection.

Healthy humans can also convert ALA to longer-chain forms of omega-3, including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), but the conversion rate is extremely low. Less than five per cent of ALA gets converted to EPA, and less than 0.5 per cent to DHA.

The long-chain (LC) varieties of omega-3 oils are important for human health, with well-documented health benefits in addition to those derived from other omega-3 oils. There is strong evidence that EPA and DHA can help lower risk factors for heart disease such as blood pressure and blood levels of triglycerides. They play a role in brain function (performance and memory) and there is some evidence they can help with conditions such as depression. Research shows they reduce inflammation and may help lower risk of chronic diseases including arthritis.

For most people, LC omega-3 oils are obtained almost exclusively from either fish in the diet, fish oil capsules or through foods fortified with LC omega-3.

More information:

Dr Ron Osmond,
0400 002 640,

ron.osmond@grdc.com.au

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