Engineered oilseed crop produces high levels of powerful antioxidant

In a major step forward for sustainable pigment production, scientists have successfully engineered the oilseed crop Camelina sativa to produce high levels of astaxanthin – a valuable red antioxidant used to color farmed salmon and shrimp – using plant-derived genes rather than bacterial pathways.

The findings, from a joint US/UK research team of biotechnologists led by Prof. Edgar Cahoon, director of the Center for Plant Science Innovation at the University of Nebraska-Lincoln (UNL), could offer a commercially viable alternative to synthetic astaxanthin, which is currently produced through costly chemical synthesis or from limited natural sources like algae.

Astaxanthin belongs to a group of red pigments known as ketocarotenoids, which are prized not only for their coloring properties but also for their exceptional antioxidant capacity. These pigments don't occur naturally in most crops, but by borrowing genes from the scarlet flax flower (Adonis aestivalis), researchers introduced a new ketocarotenoid biosynthesis pathway into Camelina seeds.

Unlike earlier efforts that used bacterial genes, this plant-derived pathway proved more efficient and cleaner. It converted nearly all the precursor ?-carotene into ketocarotenoids, with astaxanthin making up over a third of the total—reaching around 47 micrograms per gram of seed.

Image source: Roger Culos, Wikimedia Commons, CC BY-SA 4.0.