Vitamin B12 – also known as cobalamin – is an essential dietary component for humans, however people who follow a vegetarian or vegan diet are prone to B12 deficiency since plants neither make nor require the nutrient.
Since the best sources of vitamin B12 are from animal products – including eggs, milk, cheese, milk products, meat, fish, shellfish and poultry – experts note that the only reliable vegan sources of B12 come from fortified foods and dietary supplements.
But now researchers in the UK have demonstrated a way to enhance the levels of vitamin B12 in certain plants by modifying the way they are fed.
Led by Professor Martin Warren at the University of Kent, the team worked with teachers and students at a local school to investigate the detection and measurement of B12 in garden cress.
The school kids grew garden cress containing increasing concentrations of vitamin B12. After seven days growth, the leaves from the seedlings were removed, washed and analysed.
According to Warren and colleagues, the seedlings were found to absorb cobalamin from the growth medium and to store it in their leaves.
Fluorescent cress
To confirm these initial findings, the team then produced a type of vitamin B12 that emits fluorescent light when activated by a laser.
The fluorescent B12 was fed to the plants, where it was found to accumulate within a specialised part of the leaf cell called a vacuole – providing definitive evidence that certain plants can absorb and transport cobalamin.
Furthermore, the amount of B12 absorbed by the garden cress was dependent on the amount present in the growth medium, the authors said.
Warren and his team noted that vitamin B12 is unique among the vitamins because it is made only by certain bacteria, and therefore has to undergo a journey to make its way into more complex multi-cellular organisms.
By following this journey and the vitamins uptake into garden cress the team hope they can begin to understand why some people are also more prone to B12-deficiency.
Global implications?
The finding that vitamin B12 can be taken in and stored by certain plants is an important finding with global implications, say the team.
Indeed, Warren and his team say the discovery “may be important as a way to address the global challenge of providing a nutrient-complete vegetarian diet, a valuable development as the world becomes increasingly meat-free due to population expansion.”
They noted that vitamin B12-enriched plants could help overcome dietary limitations in countries such as India, which have a high proportion of vegetarians and high rates of deficiency.
Source: Cell Chemical Biology
Published online ahead of print, doi: 10.1016/j.chembiol.2018.04.012
“Construction of Fluorescent Analogs to Follow the Uptake and Distribution of Cobalamin (Vitamin B12) in Bacteria, Worms, and Plants”
Authors: Andrew D. Lawrence, et al