Washington: Researchers have claimed that exposing leafy vegetables grown during spaceflight to a few bright pulses of light daily could increase the amount of eye-protecting nutrients produced by the plants.
One of the concerns for astronauts during future extended spaceflights will be the onslaught of eye-damaging radiation they`ll be exposed to. But astronauts should be able to mitigate radiation-induced harm to their eyes by eating plants that contain carotenoids, especially zeaxanthin, which is known to promote eye health.
Zeaxanthin could be ingested as a supplement, but there is evidence that human bodies are better at absorbing carotenoids from whole foods, such as green leafy vegetables.
Plants produce zeaxanthin when their leaves are absorbing more sunlight than they can use, which tends to happen when the plants are stressed. For example, a lack of water might limit the plant`s ability to use all the sunlight it`s getting for photosynthesis. To keep the excess sunlight from damaging the plant`s biochemical pathways, it produces zeaxanthin, a compound that helps safely remove excess light.
Zeaxanthin, which the human body cannot produce on its own, plays a similar protective role in our eyes.
The CU-Boulder research team-which also included undergraduate researcher Elizabeth Lombardi, postdoctoral researcher Christopher Cohu and ecology and evolutionary biology Professor William Adams used the model plant species Arabidopsis, the team demonstrated that a few pulses of bright light on a daily basis spurred the plants to begin making zeaxanthin in preparation for an expected excess of sunlight.
The pulses were short enough that they didn`t interfere with the otherwise optimal growing conditions, but long enough to cause accumulation of zeaxanthin.
The study has been published in the journal Acta Astronautica.
