Scientists find a way to grow plants in complete darkness using ‘artificial photosynthesis’ 

If humanity ever makes the interplanetary jump from Earth to Mars, the ability to grow plants on the red planet will be vital.

Matt Damon found a way in the 2015 blockbuster hit The Martian and managed to survive on potatoes throughout the fictional storyline.

Now that vision may be getting closer to reality after scientists developed a new method of growing crops in complete darkness using artificial photosynthesis.

Researchers from the University of California, Riverside and University of Delaware used a two-step chemical electrolysis system to convert carbon dioxide, electricity and water into acetate – a form of the main ingredient of vinegar.

Food-producing organisms then consumed acetate to grow in the dark, they said.

The progress could help lead to new ways to grow food on Earth, and possibly Mars.

“Imagine if giant ships grow tomato plants in the dark and on Mars – how much easier would that be for future Martians?” said Martha Orozco-Cárdenas, the director of the UC Riverside Plant Transformation Research Center.

Study co-author Feng Jiao, of the University of Delaware, added, “If we remove the need for sunlight, we can grow multiple layers of crops at once, similar to the way mushrooms are grown, and sort of like a food factory.”

Unlike the soil on Earth, Martian regolith, as it is known, is much harder on crops, as it does not contain a significant amount of organic matter.

Mars also gets much less sunlight than Earth, so scientists need to find new techniques to improve its growth rate if food production on the Red Planet is to flourish.

It took millions of years of evolution for photosynthesis to develop in plants as a way to convert water, carbon dioxide and the energy of sunlight into plant biomass and food for humans to eat.

But the experts said this natural process isn’t particularly efficient, because only about 1 percent of the energy in sunlight gets to the plant.

The electrolyzer developed by UD efficiently converted 57 percent of the carbon molecules in carbon dioxide to acetate using a copper catalyst, creating a highly concentrated acetate stream that could be used as a plant food.

Researchers studied nine crops (lettuce, rice, cowpea, green pea, canola, tomato, pepper, tobacco and Arabidopsis, a member of the mustard family that includes cabbage and radish) and found that the plants were able to absorb carbon from the outside. . provided acetate via major metabolic pathways.

They also found that using solar panels to generate electricity to drive the chemical reaction could increase the conversion efficiency of sunlight into food and make it up to 18 times more efficient for some food products.

“We were able to grow algae completely in the dark,” said Sean Overa, a fourth-year doctoral student in chemistry at UD and co-first author of the paper.

Meanwhile, of all food crops, lettuce showed the best absorption of the acetate.

The researchers also studied where the acetate ended up in the plant.

The results showed that all plants tested were able to absorb acetate and were reasonably willing to digest and use the carbon molecules.

In some plants, the acetate was found in the plant’s amino acids, while in others it was found in sugars that the plant used as energy for growth.

“It showed us that there are digestive tracts that can be unlocked in many plant species, eventually allowing them to grow entirely on acetate,” Overa said.

“With our approach, we sought to find a new way to produce food that could break the boundaries normally imposed by biological photosynthesis,” said the study’s corresponding author, Robert Jinkerson of UC Riverside.

“Using a state-of-the-art two-step tandem CO2 electrolysis setup developed in our lab, we were able to achieve high selectivity to acetate that is not accessible through conventional CO2 electrolysis routes,” adds Jiao.

Elizabeth Hann, co-lead author of the study, said the technology was “a more efficient method of converting solar energy into food, compared to food production that relies on biological photosynthesis.”

The researchers said it also enabled a “reimagining of how food can be produced in controlled environments.”

‘Using artificial photosynthesis approaches to produce food could be a paradigm shift for how we feed people. By increasing the efficiency of food production, less land is needed, which reduces the impact of agriculture on the environment,” says Dr. Jinkerson.

“And for farming in non-traditional environments, such as space, the increased energy efficiency could help feed more crew members with less input,” he added.

The new research is published in the journal Nature Food†