Vitamin B12 is an essential nutrient for brain health, nerve function and red blood cell production. But unlike many other vitamins, it is not naturally produced by plants.
That has long created a challenge for people who follow vegetarian or vegan diets, who typically rely on supplements or fortified foods to meet their daily B12 needs.
Now researchers in the United Kingdom say they may have found a new way to add the vitamin directly to plant foods.
In a study published in Communications Biology, scientists from the John Innes Centre and partner institutions report that they successfully grew pea shoots containing the recommended daily amount of vitamin B12 using indoor farming technology.
The research team used an aeroponic system, a method of indoor agriculture in which plant roots are suspended in air and sprayed with a nutrient-rich mist. In this case, the nutrient solution contained cyanocobalamin, a common and bioavailable form of vitamin B12.
During the eight-day growing period, the pea shoots absorbed the vitamin through their roots and transported it into their leaves.
Laboratory analysis showed that a 15-gram serving of the fortified pea shoots contained more than the recommended daily allowance of vitamin B12.
“Pea shoots are literal sponges for B12, while vertical farms provide a controllable environment in which we can tailor its uptake by the plants,” said Dr. Bethany Eldridge, the study’s first author.
Because plants do not naturally synthesize vitamin B12, people typically obtain it from animal-based foods such as meat, fish, eggs and dairy. The vitamin is produced by bacteria and eventually enters the food chain through animal products.
Low intake of B12 can lead to symptoms including anemia, nerve damage, fatigue and cognitive problems. While deficiency is often associated with vegan diets, researchers note that inadequate B12 intake also occurs among older adults and people with certain digestive conditions.
To determine whether the vitamin in the pea shoots could potentially be absorbed by the body, the researchers conducted simulated digestion experiments. The tests suggested that the B12 present in the plants would likely remain available for absorption during digestion.
“The solution came not through engineering the plant but by simply exploiting the ability of the plant to take up B12 when applied,” said Dr. Jonathan Clarke, head of business development at the John Innes Centre.
The team also found that the vitamin content remained stable during cold storage, suggesting the fortified greens could maintain their nutritional value through normal distribution and retail conditions.
Researchers say the approach could potentially be used with other fast-growing salad crops grown in indoor farms or controlled agricultural environments.
Vitamin B12 deficiency remains relatively common worldwide. While supplements and fortified foods already provide effective sources of the vitamin, the researchers say incorporating B12 into fresh produce could provide another option for people seeking plant-based foods that help meet their nutrient needs.
More research will be needed to confirm how well the vitamin from fortified crops is absorbed in humans and whether the technique can be scaled for commercial food production.
Still, the findings highlight how advances in controlled agriculture may expand the ways nutrients are delivered through everyday foods.
The research was supported through grants from the Biotechnology and Biological Sciences Research Council and involved collaborations between academic researchers and indoor farming technology partners.