Australia
August 7, 2007
Grains research is exploring the
use of various biotechnological innovations to provide cereals,
pastas and breads that have added nutritional benefits.
Under a tripartite research project involving the
Grains Research and Development
Corporation (GRDC), Australian scientists are working with
both genetically modified (GM) and conventional wheat varieties
tailored to provide specific health advantages.
The research into consumer-targeted ‘healthier’ wheats is a move
away from purely agronomic applications for GM technology, such
as herbicide resistance, and is being undertaken through a joint
venture between the CSIRO, the
French farmer-owned company
Limagrain Céréales
Ingrédients and the GRDC.
The research could lead to wheat varieties that have a high
amylose content, a trait that is expected to deliver health
benefits to consumers and economic gains to growers. The first
commercial wheat varieties expressing this trait are expected
within five to six years.
Amylose is a type of starch that is more resistant to digestion
than others, meaning it releases sugars more slowly. Research
suggests that high amylose levels can improve bowel health,
reduce colorectal cancer risk and improve blood glucose control,
which is vital to managing type II diabetes and may help lower
the risk of obesity.
The High Amylose Wheat (HAW) joint venture* will build on core
technology developed by CSIRO Plant Industry and Biogemma
(Limagrain’s biotech subsidiary), which has produced an
experimental wheat variety with an amylose content of 70 per
cent.
Using CSIRO-developed RNAi gene-silencing techniques,
researchers have substantially altered starch composition,
increasing wheat’s amylose content.
Dr Matthew Morell, Advanced Genetics theme leader at the Food
Futures Flagship, says the technology has proved exceptionally
useful in defining the genetic changes required to generate HAW.
“The current team’s task is to breed the wheat using
conventional methods,” he says. “By using molecular-marker
technology we are now able to identify the genetic diversity
necessary to conventionally breed HAWs.”
While the team could proceed more quickly with a GM variety if
regulatory conditions changed, it is also looking into the
non-GM route, which Dr Morell says will take longer because of
the breeding complexities involved.
GRDC chairman Terry Enright says new value-added varieties, such
as HAWs, will provide the Australian grains industry with the
opportunity to market differentiated, high-value niche grains.
“There is a clear opportunity for the industry to provide
higher-margin specialised grain products that will enable us to
expand our markets,” he says.
Mr Enright says food processors may also benefit, with the use
of HAW varieties potentially eliminating the need to add extra
fibre to boost products’ nutritional properties.
The Food Futures director, CSIRO’s Dr Bruce Lee, says
incorporating new HAW varieties as wholegrains into breads,
cereals and other foods could increase the intake of resistant
starch to combat diet-related, non-infectious diseases such as
colorectal cancer.
“This disease represents one of the most serious health problems
in the developed world, causing premature death and disability,
and posing a serious economic and social burden,” he says. “High
levels of resistant starch give grain the potential to help
tackle this problem.”
So far, animal trials have shown that HAW produced by GM
technology improves important measures of bowel health. The next
step is a progression to large-animal trials and then controlled
trials in humans.
Plant agronomy is also being tested in field trials that have
taken place under Office of Gene Technology Regulator (OGTR)
conditions at CSIRO’s trial site in Canberra, and also in the
US. The trials were conducted to ensure the harvested wheat
retained its high amylose content.
In related studies, researchers are assessing how the wheat
performs when processed into different types of cereal-based
consumer foods.
This is an abridged version of an article that appears in
FutureCrop, published by the GRDC to inform debate surrounding
the use of biotechnology to deliver higher value crops.
FutureCrop can be downloaded from the GRDC website at
http://www.grdc.com.au/director/events/grdcpublications
Other news
from CSIRO,
from Limagrain
* Related release:
International joint
venture research project produces experimental wheat variety
with 70 per cent amylose content |
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