University of Edinburgh scientists have developed an eco-friendly way of boosting the production and heat stability of a natural blue coloring.
Led by principal investigator, Dr Alistair McCormick, the scientists have discovered that a close relative of the blue-green algae Spirulina can be engineered to produce a heat-stable form of the lucrative blue pigment at low temperatures, thus enabling the industry to scale up its production.
Phycocyanin, a blue coloring extract of spirulina, is in high demand as an alternative to artificial colorants. It happens to be the preferred source for natural blue in a rapidly growing market for natural food and drink colorants due to its anti-oxidant and anti-aging properties.
But phycocyanin’s use is limited because it is unstable at the higher processing temperatures common across many industries.
To tackle this problem, the Edinburgh team engineered the blue-green algae Synechocystis, a relative of Spirulina, to produce a more heat stable form of the blue pigment.
They achieved this by switching Synechocystis’s genetic instructions for making phycocyanin with that from another blue-green algae, Thermosynechococcus elongatus, that thrives at high temperatures.
These blue-green algae, known as thermophiles, are found in hot springs and produce a heat stable form of the pigment.
Thermophiles are however difficult and more energetically expensive to cultivate than Spirulina.
To get the best out of both, the scientists have combined Synechocystis’s ability to produce high yields of phycocyanin at lower temperatures with its thermophile cousin’s ability to make a heat-tolerant form of the pigment.
The result: Eco-friendly production of phycocyanin, allowing industry to produce higher yields of this heat-stable version of phycocyanin with lower energy costs.
What’s more, the new process drastically reduces CO2 emissions by an estimated 791 metric tonnes which is the equivalent of the annual output of 171 petrol-fueled cars.
McCormick’s team is currently working with Allgo Biosciences, a recently formed company of long-standing industry partner Tantillus Synergy Limited, to further this new technology.
Image and content: University of Edinburgh